• • •
Durham E-Theses
Some aspects of zinc accumulation in submerged
photosynthetic plants in a high zinc-level stream
Critchley, Richard W.
How to cite:
Critchley, Richard W. (1978) Some aspects of zinc accumulation in submerged photosynthetic plants in a
high zinc-level stream, Durham theses, Durham University. Available at Durham E-Theses Online:http://etheses.dur.ac.uk/9182/
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2
SOME ASPECTS OF ZINC ACCU>1ULATI0N IN SUBIfl-JBGED
PHOTOSYNrHETIC PLftNTS IN A HIGH ZINC-LEVEL STREAM
by
RICHARD W. CRITCHLEY B.Sc (DUWJLM)
M.Sc. Dissertation University of Durham September 1978
The copyright of this thesis rests with the author.
No quotation from it should be published without
his prior written cxinsent and information derived
from it should be acknowledged.
( i )
LIST OF CONTENTS
Acknowledgements
L i s t of Tables
L i s t of Figures and i l l u s t r a t i o n s
Abstract
CHAPTER 1 Introduction 1.1 General comments 1.2 The element zinc 1.3 Zinc and water
1.3*1 Factors af f e c t i n g the s o l u b i l i t y of zinc i n water
1.3.2 Water flow 1.4 Zinc i n Plant Material
1.4.1 The role of zinc i n plant metabolism 1.4.2 Zinc accumulation i n aquatic plants 1.4.3 Submerged plants as monitors of zinc
1.5 Tolerance to heavy metals 1.6 Species d i v e r s i t y i n high zinc-level streams 1.7 Background to area of study 1.8 Aims of the present study
PAGE
( i i i )
( i v )
• (v)
( v i i )
1 2 3 4
8 9
11 12 13 14 17
CHAPTER 2 Ifet e r i a l s and Methods 2.1
2.2
2.3 2.4 2.5
Water analysis 18 2.1.1 Collection and storage of water 18 2.1.2 Environmental parameters 19 2.1.3 Cation analysis 20 2.1.4 Anion analysis 20 Plant analysis 21 2.2.1 Collection and Storage of plant samples 21 2.2.2 Digestion and analyses of plant material 23 Choice of sit e s and sampling programme 24 F l o r i s t i c surrey 25 Transplant experiment 25 2.5.1 Marking and transplanting of Scapania undulata 25 2.5.2 Estimation of chlorophyll a 25
( i i ) PAGE
CHAPTER 3 Results
3.1
3 .2
3 .3
3 . ^
3 .5
3 .6
3 .7
Water' analysis 2-7 3 . 1 . 1 Heavy metal cations 27
3 .1 .2 Levels of major cations 27
3 .1 .3 The relationship between ' t o t a l ' and 'nuclepore' 29
samples 3 . 1 . ^ Anion analysis 29
Water Flow 31
Environmental parameters 31
Plant analysis 32
3 . 4 . 1 Concentration of zinc i n species sampled 32
3 . 4 . 2 Relationship between species and sites 35
F l o r i s t i c survey 37
Transplant experiment 38
Correlation analysis 35
CHAPTER k Discussion
4 .1 Water chemistry ^2 4 . 1 . 1 Sources of heavy metals i n Rookhope Burn ^2
4 . 1 . 2 The role of major cations and the speciation ^ of heavy metal cations
4 . 1 . 3 The role of anions i n zinc accumulation 45
4 . 1 . 4 The role of organic complexes 45
4 . 1 . 5 pH and temperature effects 45
4 . 1 . 6 Levels of flow i n the stream 45
4 .2 Plant material... 47
4 .3 Relationship to other studies 48
4 . 4 Plants as monitors of zinc i n natural waters
References
Summary 51 58
Appendices A - D 59
( i i i )
-ACKNOWLEDGEMENTS
I wish to thank my supervisor, Dr. B.A. Whitton for his help and advice throughout the course of t h i s dissertation, N
Thanks also go to Mr. W. Simon and Mr. T. Brett for invaluable assistance with technical aspects of the study.
Acknowledgements also to Mr. P. Entwistle of Swiss Aluminium Mining (UK) f o r helpful discussion and to Mr. J.M. Storey of Northumbrian Water Authority f o r discharge figures i n Rookhope Burn.
Special thanks to Mrs. Marjorie Macdonald fo r typing t h i s manuscript and to my wife and family for patience and understanding throughout.
The study was completed while on study leave from Newcastle-upon-Tyne Polytechnic for whose support I am most grateful.
\
( i v )
LIST OF TABLES FOLLOWING • PAGE
TABLE 1.1 Enrichment r a t i o s from three studies i n the ) Northern Pennine o r e f i e l d . )
TABLE 1.2 Previous reports of alga l and bryophyte species occurring ) i n streams carrying high levels of heavy metals.
TABLE 2 .1 L i s t of sampling s i t e s i n Rookhope Burn catchment. ) 1
TABLE 2 .2 L i s t of transplant s i t e s i n upper Rookhope valley )
TABLE 3 .1 Mean levels of Zn, Pb and Cd i n water at collection s i t e s i n Rookhope Burn catchment
TABLE 3 .2 Mean levels of Zn, Pb and Cd i n 'nuclepore' water samples and water flow on six sampling dates i n Rookhope Burn catchment.
TABLE 3 .3 Mean levels of Ca, Mg and Fe i n water at collection s i t e s i n Rookhope Burn catchment.
TABLE 3 .4 Mean levels of Ca, Mg and Fe i n 'nuclepore' water samples on s i x sampling dates i n Rookhope Burn catchment.
TABLE 3 .5 Meain levels of Fe i n ' t o t a l ' and 'nuclepore' water samples at c o l l e c t i o n s i t e s .
TABLE 3 .6 Mean levels of anions i n water at col l e c t i o n sites i n Rookhope Burn catchment.
TABLE 3 .7 Mean levels of anions i n Rookhope Burn catchment.
TABLE 3 .8 Mean pH, temperature, t o t a l a l k a l i n i t y , e l e c t r i c a l conductivity and o p t i c a l density of water at sampling s i t e s i n Rookhope Burn catchment.
TABLE 3.9> Levels of Zn i n water and plant material and accumulation i - V r a t i o s f o r species sampled.
TABLE 3.10 Result of f l o r i s t i c survey of submerged plants i n the study area, including a u t h o r i t i e s .
TABLE 3 .11 Growth of marked shoots of Scapania undulata at transplant s i t e s .
TABLE 3 .12 Chlorophyll a/pheophytin a r a t i o i n marked shoots of Scapania undulata
TABLE 3,13 Levels of Zn i n Scapania undulata and i n 'nuclepore' water samples at transplant s i t e s
TABLE 3»14 Mean levels of chemical and physical variables i n water during the sampling programme.
TABLE 3.15 Correlation matrix f o r mean levels of chemical and physical variables i n water.
TABLE 4.1 Levels of Zn i n plants and water reported i n studies i n the mineralised area of Weardale.
11
24
27
28
30
32
37
38
39
49
(v)
FIGURE 1.1
FIGURE 1.2
FIGURE 1.3
FIGURE 1.4
FIGURE 1.5
FIGURE 1.6
FIGURE 2.1
FIGURE 2.2
FIGURE 2.3
FIGURE 2.4
FIGURE 3.1
FIGURE 3.2
FIGURE 3.3
FIGURE 3.4
FIGURE 3.5
FIGURE 3.6
LIST OF FIGUR];]S AND ILLUSTRATIONS
Ifep showing the d i s t r i b u t i o n of zinc i n sediments collected from streams i n Northern England during 1969.
Regional geology of north-eastern England. )
Sketch map of the River Wear Basin showing the ) geological structure. )
Sketch map of Rookhope Burn showing sites of ) mining a c t i v i t y and sampling sites of present study. )
) Sketch map showing the d i s t r i b u t i o n of minerals i n ) the Northern Pennine Orefield. (a) Photograph of upper Rookhope showing t a i l i n g s
heaps.
(b) Photograph of upper Rookhope showing Grove Rake mine.
(a) Photograph of South Grain at s i t e one.
(b) Photograph of upper Rookhope Burn looking downstream towards s i t e two,
(a) Photograph of Rookhope Burn looking downstream from feite three
(b) Photograph of Rookhope Burn looking upstream from s i t e four.
Photograph of Rookhope Burn looking downstream from s i t e fxye.
Photograph showing Scapania transplant.
Variation i n mean levels of Zn, Pb and Cd i n 'nuclepore' water samples at sampling s i t e s .
Variation i n mean levels of Zn, Pb and Cd i n 'nuclepore' water samples over sampling programme.
Variation i n mean levels of Ca, Mg and Fe i n water at sampling s i t e s .
Variation i n mean levels of Ca, Mjg and Fe i n water over sampling programme. )
) Variation i n mean levels of Fe i n ' t o t a l ' and 'nuclepore' ) water samples. Variation i n levels of anions i n water at sampling s i t e s .
FOLLOWING PAGE
14
15
16
24
25
27
28
30
( v i ^
FIGURE 3.7
FIGURE 3.8
FIGURE 3.9
FIGURE 3.10
FIGURE 3.11
FIGURE 3.12
FIGURE 3.13
Variation i n mean levels of anions i n water over sampling programme.
) Variation of Zn i n water, water flow and discharge j over sampling programme.
Variation i n pH, t o t a l a l k a l i n i t y and e l e c t r i c a l \ conductivity at sampling s i t e s . \
) Variation i n op t i c a l density at sampling s i t e s , j
Scatter diagram to show relationship between zinc content of plant material and •nuclepore' l e v e l of zinc f o r species sampled.
Scatter diagram to show relationship between zinc content of plant material and 'nuclepore' l e v e l of zinc f o r sites sampled.
Scatter diagram to show relationship between enrichment r a t i o s and 'nuclepore' levels of zinc for species sampled.
30
31
35
36
( v i i ) ABSTRACT
During the course of the present study data was collected i n r e l a t i o n to the accumulation of zinc i n submerged plant species i n an upland stream flowing through a mineralised area.
The zinc contents of seven submerged species of algae and bryophytes were determined and related to the chemistry of the water from which they were collected. Accumulation i s approximately l i n e a r f o r a number of species within defined environmental l i m i t s of zinc.
Evidence from transplant experiments does not support the view that tolerant strains of Scapania undulata (L.) Dum. e x i s t .
The use of plants as r e l i a b l e monitors of elevated levels of zinc i n natural waters and the inter-relationship of environmental parameters are discussed. The p o s s i b i l i t y of using transplant techniques to monitor zinc levels i s further discussed.
CHAPai^J.
DCTRODUCTION
1.1.1 General Comments
I n recent years great concern has been shown over the effects of p o l l u t i o n i n the sense of the introduction of harmful materials into the environment as a result of man's a c t i v i t i e s . Disasters such as that which occurred at Minamata from 1953 - 6 l when organic-mercury was released i n to the aquatic environment are well documented ^^'^1^®-'' • '' , Less dramatic examples however can be
Irukayama 1961)
found i n any heavily i n d u s t r i a l i s e d society such as B r i t a i n and
as the l e v e l of operations increases, so does the problem posed
by elimination of the waste materials of those a c t i v i t i e s . The
natural cycles operating w i t h i n the environment are no longer able
to cope with the rate of discharge.
Heavy metals, defined as those with a density greater than f i v e
(Passow et a l . l 9 6 l ) , such as zinc, lead and cadmium are used
extensively i n i n d u s t r i a l processes. Galvanising, electroplating,
the electronics industry, paper processing and psiint manufacturing
industries are a l l producers of heavy metal wastes and a l l have an
increasing importance i n the economy of i n d u s t r i a l nations.
I n s i t e s of natural occurrence of heavy metal ores, where lodes are
exposed to weathering actions, high metal levels w i l l be produced,
but mining a c t i v i t i e s may magnify the levels to problem proportions.
I n B r i t a i n , one such area i s the Northern Pennine Orefield which,
at the end of the nineteenth and beginning of the twentieth centuries
was extensively mined f o r lead. Although lead mining i s no longer
carried out, the legacy of s p o i l heaps, with t h e i r persistent heavy
metal levels (Jones 1958), and the reworking of both s p o i l heaps
- 2 -
and closed mines i s a present feature of the area. Today's
mining a c t i v i t i e s are for the extraction of fluorspar, a non-
metallic mineral extensively used i n the steel and plastics
industries.
There are a number of extensive studies on the effect of mine (1940n
workings, notably by Carpenter (1924) and Jones j^^Q^ •> both
working on the River Ystwyth i n mid-Wales. More recent work
has been concerned with the use of aquatic plants ajs indicators
of raised levels of heavy metals i n water. (The work of Goodman
and Roberts (1971) and L i t t l e and Martin (1974) i n devising a
system for monitoring levels of Zn, Pb and Cd i n a i r encourages
the search for suitable aquatic species). Whitehead and Brooks I
(1969) have advocated the use of aquatic bryophytes as indicators
of uranium mineralisation and Lloyd (1977) has investigated the
accumulation of zinc i n a number of plant species growing i n waters
with raised levels of heavy metals. However the number of studies
i s l i m i t e d , and i t i s the aim of t h i s project to measure some of
the physical, chemical and bi o l o g i c a l parameters r e l a t i n g to the
uptake of a heavy metal, zinc, by submerged aquatic plant species
growing i n an area of past and present mining a c t i v i t y . 1.2 The Element Zinc
Zinc, as i t s ore, and i t s oxide, cadmia was used by the Romans,
being smelted, together with copper ores and calamine to produce
brass, but i t does not seem to have been recognised as a separate
metal u n t i l 17OO, by Ktinkel (Sherwood-Taylor 1954). I t occurs n
nature as two major ores, zinc blende or sphalerite, ZnS and
calamine or zinc csirbonate, Zn CO , from which i t i s smelted before
- 3 -
p u r i f i c a t i o n by e l e c t r o l y s i s .
1 . 3 Zinc and Water
Before entering i n to a relationship with water and being
released into the environment, ores of heavy metals must be
oxidised to form soluble compounds. Under natural conditions
t h i s exposure to oxidising conditions occurs when geological
phenomena cause the emergence of ores to the atmosphere. Ifen's
influence can accelerate the process by means of drainage from
mines and the formation of s p o i l heaps. Sulphide i s the
commonest form of heavy metals and oxidation would be expected
to produce sulphate ion, SO,2- , . . . ... , ,
4 , and also intermediate products
of free S and SO , but these occur rarely i n oxidised zones
(Krauskopf 1967). Conversion occurs to insoluble compounds which
are stable under surface conditions - oxides, carbonates, sulphates
or s i l i c a t e s - which are carried down to unoxidised regions of the
ore deposit and precipitated by reaction with sulphide minerals.
Any soluble products formed w i l l be removed completely i n run o f f .
The importance of water i n the oxidation process i s not completely
understood. Krauskopf (I967) suggests i t s role as that of providing
carbonic acid to dissolve out sulphide to form ions and allow
quicker reaction with oxygen, while Sato (196O) proposes the
oxidation of water to hydrogen peroxide, ^2^ which then oxidises
the sulphide. An overall equation f o r the oxidation of zinc
sulphide might be: ZnS + 20^ + 2HCO2 ZnCO^ + H CO + SO ^"
but i t i s more r e a l i s t i c to imagine the oxidation as a- number of
small steps each taking place i n s l i g h t l y different.chemical
environments and the actual pathway d i f f e r i n g with l o c a l conditions.
. k -
This oxidation of sulphide leads to the formation of acid
solutions, either by hydrolysis of the metal ion or by
p r e c i p i t a t i o n of the insoluble hydroxide, the degree of a c i d i t y
varying with the proportion of d i f f e r e n t metal ions present i n
the ore bed. Where a large proportion of iron ore i n the form
of sulphide i s present, f e r r i c oxide i s formed which i s very
insoluble:
4 FeS^ + I5O2 + SH^O. ^Fe^O^ + 8S0^^" + i6h"^
Mean levels of zinc i n surface waters may be rather meaningless
because of the v a r i a b i l i t y i n l o c a l conditions and also the extent
of man's influence, but Wedepohl (1972)suggests a figure of
10 Jig 1 Zn. Abdullah and Royle (1972) f i n d an average le v e l of
zinc i n streams unaffected by ore deposits of 11 jig 1 . Reported
levels of Zn i n natural waters however are d i f f i c u l t to evaluate
since the method of water c o l l e c t i o n , p a r t i c u l a r l y i n e a r l i e r work,
i s often not specified nor whether i t represents the toteil water
sample or one which has been f i l t e r e d to remove suspended materials.
I n h i s large scale survey i n I969 of the elemental content of
stream sediments over the U.K. Thornton (1974) finds very high
levels of Zn, ,^800000 p.p.m, i n areas of past and present mining
a c t i v i t y (Fig l . l ) , while i n an analysis of fluorspar mine
waste i n Weardale a l e v e l of 20 36O^g g Zn i s found by Cooke
et a l . ( l 9 7 6 ) .
1 . 3 . 1 , Factors a f f e c t i n g the s o l u b i l i t y of Zinc i n Water
i . £H
Streams with low pH values ( < 3 ) i generally
associated with coal mining a c t i v i t y , are associated
with high levels of heavy metals (Hargreaves et a l .
1 9 7 5 ) . This can be related to the p r e c i p i t a t i o n of
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F i g . 1.1 Map sho\idng the d i s b r i b u t i o n oT zi.ic i n sedimotihs c o l l e c t e d from streamr; i n Northern England durinc 19^9
(after Thornton 1974)
- 5 -
insoluble hydroxides i n simplified systems under conditions f a l l i n g below pH7 (Bachmann I 9 6 I ) .
Zn "" + H^Q^ ZnOH"" + H"" Z n (OH)^ 4^+ H""
Jurniak and Inouye (I962) demonstrated the
s o l u b i l i t y of zinc i n d i s t i l l e d water i n a ZnCl^ -
NaOH system and show that as the pH rises above 6.8
s i g n i f i c a n t decreases i n the l e v e l of dissolved Zn
occur. Grime and Hodgson (I969) report that many
minerals become soluble as pH f a l l s and as they then
become more available f o r uptake, become toxic. As
pH f c i l l s below pH 4.5 i n s o i l s aluminium t o x i c i t y
i s induced i n Rumex acetosa and Holcus leinatus
resulting i n a catastrophic decline i n t h e i r % occurrence.
I n stream conditions the simple model of Jurniak and
Inouye w i l l be complicated by competition reactions
occurring between Zn and other cations and t h i s
phenomenon i s used i n the p r e c i p i t a t i o n of heavy
metals i n settlement ponds (P. Entwistle pers. coram,)
(1.7)
i i . Complexing of Zn
The production of the hydroxide complex of zinc i s
also complicated by the presence of other anions
I n sea water Zirino and Yamamoto (1972) show that at
pH 8.1 i t i s of greater importance than others, but as
pH i s lowered to pH 7.0 i t s importance decreases, with
an increase i n Chloride (ZnO!* and ZnCl2°), carbonate
(Zn C0^°) and sulphate (ZnSO| °) complexes. Hem
(1972) i n reviewing various data on the s o l u b i l i t y of
zinc i n various inorganic aquegus environments
indicates a minimum value f o r zinc concentration at
- 6 -
pH 9.5, while remaining i n solution as the dominant species (Zn^^) up to pH values a l i t t l e over 7.0.
The effect of elevated phosphate levels i s demon
strated by Jurniak and Inouye (1962) i n t h e i r work
on the s o l u b i l i t y of zinc i n d i s t i l l e d water, where at
high levels a l l zinc i s precipitated as zinc phosphate.
The effect of increasing pH on t h i s reaction i s to
decrease levels of ionic zinc (Zn^^) and phosphate.
I n upland streams where man's a c t i v i t i e s are minimal,
low levels of phosphate would be expected, but where
for instance a sewage treatment plant was operating
then phosphate enrichment might be expected to have
an effect on zinc s o l u b i l i t y . Rana and Kumar (1974)
also propose the formation of complexes between
phosphate and zinc ions at c e l l membranes rendering
the zinc less mobile.
i i i . Organic Complexes
Stumm and Morgan (1970) f i n d that many heavy metals
are found i n stream and lake waters at much higher
concentratione.ths.t can be explained by t h e i r
theoretical s o l u b i l i t i i ^ s and propose a cl a s s i f i c a t i o n
of metal ions and complexes i n natural waters. I n
addition to free ions they separate p a r t i c l e s on t h e i r
size i n to inorganic complexes (<" lOimi) chelates
and colloids (10 - lOOnm) and large colloids and
precipitates ( >100nm). A number of substances have
been proposed as ligands i n forming complexes with
- 7 -
cations and increasing t h e i r s o l u b i l i s a t i o n . Perhac (1974) notes that flowing waters can carry large amounts of heavy metals i n c o l l o i d a l form. Many of these colloid; are associated with organic acids produced by decaying plant material (humic and f u l v i c acids) forming complexes (Shapiro 1964). The upper reaches of upland streams, draining o f f blanket peat can be expected to contain high levels of humic compounds and t h i s author has observed brown organic material i n the upland reaches of the River Wear system and they have also been observed by Say (1977) i n the River South Tyne catchment.
The metal complexing capacity of the humic acids of s o i l
i s noted by Randhawa and Broadbent (I965) to be pH
dependent. The t o t a l zinc forming complexes with humic
acids increases with r i s e i n pH up to 8,5, but declines
again at high values. Schnitzer (l97l) shows that zinc
can be mobilised by f u l v i c acids at pH levels at which
i t would normally be insoluble,
i v . Total A l k a l i n i t y
Ernst,Allen and Mancy (1975)Produce s o l u b i l i t y curves
f o r zinc at d i f f e r e n t levels of a l k a l i n i t y and show the
lowest s o l u b i l i t y with the highest a l k a l i n i t y , but
further show the overriding effect of pH, with rapid
losses of Zn occurring at a l l a l k a l i n i t i e s when pH rises
above pH 7.5. Say (1977) finds a marked reduction i n
the t o x i c i t y of zinc to laboratory population of . the
alga Hormidium r i v n l a r e i n the presence of both Ca and Mg
and observes large numbers of 'particles' deposited i n
the mucilage attached to Hormidium rivu l a r e at pH values
- 8 -
7 and 8, making the tentative suggestion that they
could be l o c a l i s e d deposits of precipitated Zn (OH)^.
10-2- Water Flow
Levels of soluble metals i n natural vraters are believed to
be higher during low flows (Jones 1 9 ^ , 19^8) when
dilut i o n by uncontaminated run off i s l e a s t . Low flows
occur t y p i c a l l y during summer months. I n contrast, the
suggestion has been made that metals weathered to soluble for:
may be flushed out of old mine workings and t a i l i n g s by
r a i n f a l l i n g a f t e r warm dry s p e l l s (Carpenter 1925). In
a programme of sanipling and analysis from the River Ystwyth
i n mid-Wales, Grimshaw et al.(1976) show both seasonal
and short-term v a r i a t i o n s . High concentrations of zinc are
observed both at times of low flow and during the i n i t i a l
phases of storm run off, and they point to summer
convection storms i n mining areas as being of part i c u l a r
importance to r i v e r biota. I n re l a t i o n to seasonal variatioj
they find a much greater range i n bulk metal supply than i n
concentrations. Clearly duration of contact with sources
of Zn, whether of an intermittent or continuous nature w i l l
a f f e c t accumulation i n the biota.
1.^ Zinc i n Plant Jfaterial
l . ' f . l The role of Zinc i n plant metabolism
The growth promoting effect of zinc on the mould
Aspergillus niger was reported i n I869 by Kaulin and
demonstrated on maize by Ifeze i n 191^1 but i t s essential
plant nutrient effect was not generally accepted u n t i l the
1930's (Price 1970). Since then i t s e s s e n t i a l i t y i n small
- 9 -amounts has been shown i n Rhizopus nigricajis (Waksmain and Foster 1938), f l a g e l l a t e s (Ondratscheck 13kl), Chlorella pyrenoidosa (Myers 19^1) and r a t s (Todd et al.l93if). Higher plants require of the order of 1 ji mole zinc g dry weight (Price 1970). Price and Quigley (1966) working on cultures of Euglena show a l i n e a r relationship between growth rate
' and i n t e r n a l zinc concentrations. Synthesis of s p e c i f i c c e l l constituents may require more zinc than normal growth and zinc i s reported as a constituent of cytochrome c i n Pstilago sphaerogena (Brown et al.1966) and for s p e c i f i c enzyme production i n Escherichia c o l i (Torriani et al.quoted by P r i c e I966). Price(1970) reports; that the a b i l i t y of plants to remove zinc i s retained down to l e s s than 10 nM but i t appears that once assimilated i n to a t i s s u e , i t i s v i r t u a l l y immobile (Millikan ajid Hanger I965).
1.4.2 Zinc accumulation i n aquatic plants
Accumulation i s the process whereby a plant can take up ions
against a gradient so that the internal concentration i s
greater than that i n the external environment. Two
approaches have been adopted by workers to the process of
accumulation of heavymetals. The f i r s t attempts to r e l a t e
elemental composition of plant material to that of the
aquatic environment, while the second investigates the
physiological mechanism of elemental uj^baike, frequently
employing radio-nuclides as l a b e l s . One example of t h i s
second approach i s the study by Pickering and Puia (1969) on the uptake of ^^Zn i n Fontinalis antipyretica which
shows three phases. The f i r s t i s rapid and i s ejcplained
as processes of ion-exchange and adsorption i n the
free-space of the c e l l u l a r membrane; the second l a s t s some
- 10 -
90 minutes and i s uptake through the outer layer of the protoplast, which acts as a diffusion barrier; the f i n a l phase, which can be inhibited by metabolic factors, i s
I one of active accumulation i n the c e l l vacyde. McLean and Jones (1973)» i n a study of Scapania undulata find two uptake mechanisms, an active system at "zinc l e v e l s of Or-10 mg 1 Zn and a passive system at l e v e l s of 10-2^ mg 1 Zn. They propose a s e r i e s of s i t e s , possibly within the c e l l w all, for active uptake, which when saturated at higher l e v e l s of Zn allow the metal to swamp the c e l l .
I n the t e r r e s t i a l moss, Rhytidiadelphus squarrosus Gullvag
et a l . ( l 9 7 ^ ) show accumulation of lead within the cytoplasm
and nucleus as lead inclusion bodies and Stokes (1973) finds
intranuclear inclusions i n copper tolerant Scenedesmus sp.
when fed on Cu SO .
Bryan (I969) studying uptake of ^^Zn i n Laminaria digitata
finds i t to be a gradual net uptake process with no evidence
that exchange of zinc takes place. Because uptake i s not
regulated, the older part of the lamina contains more zinc
than younger portions. Similarly, Lloyd (1977) finds
increased l e v e l s of zin c , lead and cadmium i n older material
of F o n t i n a l i s antipyretica i n the River Wear system, and
Harding (1978) increasing l e v e l s of zinc i n older sections
of filaments of Lemanea f l u v i a t i l i s from the River Derwent.
The relationship between l e v e l s of metals i n plant material
and that i n t h e i r aquatic environnent gives r i s e to a
quantitative assessment of the accumulation of heavy metals
by aquatic organisms and the term 'enrichment r a t i o ' was
- 11 -
proposed by Brooks and Rumsby (1965) i n their studies
of New Zealand bivalves. Other workers have used similar
terms including concentration factor (Bowen I966) and
enrichment factor (Dietz 1973) hut the term enrichment
r a t i o , as defined below and used by Whitton and Say (1975)
i s used i n t h i s study.
Enrichment r a t i o = Concentration i n the orgstnism (JJ^ g ." dry weight Concentration i n surrounding medium (tng ^~'')
Studies of accumulation of heavy metals i n t e r r e s t i a l
plants are numerous including work by Turner (1969),
Antonovics et al.(197I) on angiosperms, Brown, and Bates
(1972), Ward et al.(l977) on bryophytes. Preston et a l .
(1972), Foster (1976) show accumulation i n marine algae.
Less work i s available on fresh water species. An analysis
of Ih freshwater genera by Boyd and Lawrence (I967)
gives enrichment r a t i o s varying from 3 000 to 12 000 for the
majority of elements and marked enrichment for Zn, Cu,
Fe and Mn. Studies i n the old lead mining area of Durham
by Leeder (1972), Harding (1977) and Lloyd (1977) show a
wide va r i a t i o n for a number of aquatic species. (See
Table l . l ) .
1.4.3 Submerged plants as monitors of zinc
The use of aquatic plants as monitors or indicators of
heavy metals hinges on the s t a b i l i t y of the enrichment
r a t i o s i f the conditions affecting the plant and the water
remain constant. F i e l d studies by Keeney et al.(l976) and
Lloyd (1977) on fresh water algae and bryophytes show con-
siderable enrichment of zinc but there i s l i t t l e com
p a r a b i l i t y between species and t h i s i s probably to be
TABLE 1.1 ENRICm-IENT RATIOS FROM STUDIES IN THE NORTHERN-PENNINE OREFIELD
Leeder (1972)
Lloyd (1977)
AUTHOR SPECIES
Lemanea f l u v i a t i l i s
Hygrohypnum ochraceum
Mmulus guttatus
Mougeotia sp.
Scapania undulata
Hygrohypnum ochraceum
Mimulus guttatus
Harding (I978) Lemanea f l u v i a t i l i s
Scapania undulata
Hygrohypnum ochraceum
ENRICHMENT RATIO
7000 - 92000
15000 - 300000
500 - hooo
1030
1150 - 130000
h^OOO - 120000
11500 - 38500
3000 - .16000
11000 - 37000
5000 - 16000
TABLE 1.2 PREVIOUS REPORTS OF ALGAL AND BRYOPHYTE SPECIES OCCURRING IN STREAMS CARRYING HIGH LEVELS OF HEAVY METALS
AUTHOR
Carpenter (192^)
Reese (1937)
" (19^)
Whitton (1970)
McLean and Jones (1975)
G r i f f i t h s et a l . (1975)
Say (1977)
SPECIES Batrachospermum sp., Lemanea f l u v i a t i l i s
Ulothrix sp., StigeoQ^lojiium tenue, Lemanea f l u v i a t i l i s , Mougeotia sp.,
' Microspora sp.
Scapania undulata
Microspora sp., Stigeoclonium tenue, Spirogyra sp., Ulothrix sp.
Hormidium r i v u l a r e , Scapania undulata, Microspora sp., Ulothrix sp.
Ulothrix sp., Hormidium sp., Mougeotia sp,
Hormidium r i v u l a r e , Mougeotia sp., Scapania undulata, Philonotis fontana, Dicranella v a r i a , Dichodontium pellucidum
- 12-e3q)ected since chemicsil conditions such as pH, species of
metal present are l i k e l y to be very different. In reviewing
accumulation of heavy metals by algae, Lloyd (1977) finds great variation from species to species and even within the
same species of alga Harvey and Patrick (I967) point to surface area r- voliime relationships as being important and
differences i n morphology, growth rate and seasonal
appearance would seem to be si g n i f i c a n t . One advantage i n
the use of algae as monitors i s that they obtain metals
only from the surrounding waters but t h i s i s not so cl e a r l y
the case i n bryophytes with t h e i r rhizoidal attachments
to the substratum. LLoyd finds accumulation i n bryophytes
to higher l e v e l s than any algae or angiosperms and
Erapain (1976) points to the integrating effect of aquatic
bryophytes i n smoothing out fluctuations of concentration
of heavy metals i n the aquatic environment. Many species
of bryophytes however do not remain permanently submerged
p a r t i c u l a r l y through summer droughts and t h i s author has
observed periodic inundations and exposures of a number of
bryophytes during the course of the present study. Con
tamination by s i l t and growth of epiphytic species are two
fiirther problems, affecting both algae and bryophytes,
experienced by t h i s author and by Lloyd' (1977)*
1.5 Tolerance to Heavy Metals
I n a review of heavy metal tolerances i n plants Turner, (1968) reports many species as being tolerant and able to survive
at concentrations of heavy metals which exclude other species.
Thus, studies on lead tolerant Agrostis tenuis (Jowett 1964),
-13 -
and Festuca ovina (Wilkins 1957) and copper tolerant Agrostis tenitis (McNeilly and Bradshaw I968) show the s p e c i f i c i t y of the tolerances and their high h e r i t a b i l i t y Whitton and Say (1975) report Lemanea sp. and possibly Batrachospermum sp. as being highly resistant to both zinc and lead with the green algae Microspora sp. and Ulothrix sp. as being tolerant to copper, zinc and lead. Say (1977)1 i n studying populations of Hormidium sp. growing i n high concentrations of Zn, shows them to be adapted forms and for Hormidium rivulare that t h i s adaptation may be genetically determined. Duncker (1976) i n a transplant and t o x i c i t y t e s t s of populations of the bryophyte Scapania undulata from high and low concentrations- of zigc i n stream water f a i l s to support evidence for resistant s t r a i n s , but her investigation was made d i f f i c u l t by drought affecting a l l f i e l d populations.
Turner (I968) i n reviewing tolerance proposes two possible
mechanisms, one of exclusion from the metabolic system of
heavy metal ions, and one of i s o l a t i o n of the metal within
the c e l l allowing normal processes to continue. He points
to the role played by the c e l l wall i n acting as a heavy
metal accumulator i n plants.
1.6 Species d i v e r s i t y i n high Zinc-level streams
Extreme environments i n the sense of Brock (1969) are
characterised by a low species diversity and Whitton and
Say (1975), i n reviewing the effects of heavy metals on the
f l o r a and fauna of r i v e r s , report the effect of Zn i n reducing
- 14 -the number of 'dominant' species. In a survey of the f l o r a
of high z i n c - l e v e l streams. Say (1977) finds that
filamentous green algae, i n particular Hormidium rivulare
and Mougeotia sp. are the most abundant algae throughout
a range of high zinc values with other algae showing more
r e s t r i c t e d d istributions. Scapania undulata, Philonotis
fontana and Dicranella v a r i a were the bryophytes capable
of growing throughout the range of elevated zinc values.
At highest zinc l e v e l s he finds a l g a l communities dominated
by species including Hormidium, Mougeotia and the bryophytes
Bryum pallens, Pohlia nutans and Dichodontium pellucidum.
I n a botanical survey of Rookhope Burn^Leeder (1972) finds the stream to be f l o r i s t i c a l l y poor with only one
bryophyte, Hygrohyphum ochraceum and one alga, Lemarjea
f l u v i a t i l i s growing i n s u f f i c i e n t quantities for h i s analysis
of heavy metals.
Table 1.2 shows some of the species previously reported
from streams with high Zn-levels.
1.7 Background to area of study
The following discussion of geology and mineralogy of the
study area i s l a r g e l y from Dunham (1945).
The Pennine Ridge from the English Midlands to the Scottish
Borders i s characterised by continuous outcrops of lower
Carboniferous s t r a t a which are extensively mineralised i n
Derbyshire and a group of northern dales (Allendale, Alston
Moor, Jrfeardale and T ^ s d a l e ) . In the northern dales of the
Alston Block ( F i g 1.2) the majority of lead-zinc deposits are
found i n e i t h e r the sandstone shales or limestones of the
Toredale Series underlying the Millstone Grit (Fig. 1.3).
This Northern Pennine Orefield includes the RLver Wear Basin.
Fig..1.2 Regional Geology of North Eastern England
(After Smith, 1923, F i g . 2.1) • '
9 o r o B
Base of Permian
Base of Carboniferous
faior f a u l t s
F i g . 1.3 Section map of the River V/ear Basin showing the geological structure.
Carboniferous LiTuestoae Series
Millstone G r i i
Coal Measures
Magnesian Limestone
Whin Dyke
RHB Rookhope Burn
\
- 15 -The metalliferous sirea of Weardale extends eastwards from the pass of KiUhope for some 3'f km to Harperley embracing i n addition to.the valley of the Wear, side valleys to north and south including Rookhope Valley, the area of the present study. The o r e f i e l d was formerly the most productive area i n England for zinc and lead concentrates and since the end of the nineteenth century i s second only to Derbyshire i n the production of fluorspar. Mineral veins intersect throughout the o r e f i e l d with minerals occurring as bands i n veins running v e r t i c a l l y or thin horizontal sheets or f l a t s ( f i g . I . 5 ) .
The minerals of economic importance formed i n the deposits,
referred to as primary minerals, consist of galena (PbS),
sphalerite (Zn S) and f l u o r i t e (CaF^). Barite (Ba SO^)
and witherite (Ba CO^) formed the basis of a thriving bairytes
industry at one time i n Weardale, but i n Rookhope Valley form,
along with quartz. (SiO^), chalcopyrite (CuFeS^) and c a l c i t e
(CaCO^), the major gangue minerals.
Rookhope Burn a r i s e s as a number of small streams flowing off
the f e l l s to the east of Allenheads Village (grid
reference NY 862^53). I t runs east for some 7 km to Rookhope
Village (grid reference NY 9^^27) and then south for 5 km to
j o i n the River Wear beyond Eastgate (grid reference NY 9535^6)
Lead mining has a long history i n Rookhope Valley dating
back to Norman times, but the large scale development was
begun i n the early eighteenth century by the Beaumont
Company. The Weardale Lead Company took over the mining
a c t i v i t i e s i n I883 and a c t i v e l y produced lead u n t i l 1931* The present mining i n the Valley i s for fluorspar, two
old lead mines having been re-opened. Grove Rake mine
F i g . 1.4 Sketchraap of Rookhope Burn shov/ing s i t e s . of mining a c t i i r i t y and sarapling s i t e s of .present study.
Active r.lnorsprar mine
Old shafts
Fdne tai.lings
oampling s i t e (1 - 6)
?capania transplaat s i t e (A-C)
/
F i g , 1.5 Sketch map showing the d i s t r i b u t i o n of minerals i n the Northern Pennine Orefield.
(After Dunliam 1943)
NOTE: Mineral Veins oiily included i n central sirea.
5 "»
.1 2
IA
- 16 -
(grid reference NY 8^kkk2 F i g l.^f , 1.6) near the head
of Rookhope Burn, operated by the B r i t i s h Steel Corporation,
and Redburn Mine (grid reference NY 928'+31; f i g l.^f) just
above Eookhope Village, now operated by Swiss Aluminium
Mining (U.K). This l a t t e r corporation also operates a washing
plant i n Rookhope Village which treats ore from the mine and
processes the old lead mine t a i l i n g s from around the smelter.
Associated with t h i s plcint are a number of settlement pools
i n which ore from which fluorspar has been removed i s f i r s t
treated with ferrous sulphate and l a t e r lime to precipitate
heavy metals before the effluent i s discharged i n to Rookhope
Burn (p. Entwistle pers, comm). Farther prospecting by
Swiss Aluminium Mining (U.K) over some 200 sq. miles at
present being carried out may lead to the sinking of new shaft
The e a r l i e r mining a c t i v i t i e s have.left behind large heaps
of waste t a i l i n g s on the banks of Rookhope Burn from
Corbitmere Dam (grid reference NY 877446; F i g . 1.4) down to
the v i l l a g e of Rookhope and drainage channels and
from the mines themselves. Run off from the t a i l i n g s heaps
and mine drainage water contribute to the waters of the
stream.
The only other occupation of any significance i n the valley
i s sheep farming on the upper f e l l s and to improve grazing
land extensive drainage has been ceirried out involving the
cutting of deep channels through the peat to a s s i s t run
off of surface waters.
F i g . 1,6 (a) Upper Rookhope sho\idr45 t a i l i n g s heaps.
(b) Upper Rookhopo showing Grove Ea3xe mine.
- 17 -
1.8 • Aims of the present study
Jones (1938, 1964) , and Jones and Howells ( I 9 6 9 ) , i n work
on the River Ystwyth and Rheidol i n mid- Wales show that
zinc pollution i s a persistent problem whether due to
drainage from old mine workings or work relating to new
prospecting. The catchment area of Rookhope Burn lends
i t s e l f well to a study of accumulation of zinc i n submerged
aquatic species having effects from old mine workings and
present mining a c t i v i t i e s .
,The aims of the present study i n t h i s area are then:
i . to investigate the distribution of submerged algae and
and bryophytes with a view to assessing their usefulness
as monitors of zinc pollution,
i i . To c o l l e c t botanical and hydrogeochemical data on l e v e l s
of zinc i n submerged algae and bryophytes i n a stream
receiving effluent from areas of past and present mining
a c t i v i t y .
i i i . To investigate the effect on growth of transplanting
plant material from regions of low and higher zinc
concentrations with a view to discovering evidence of
ecotypic tolerance within a species.
CHAPTER 2
MATERIALS AND METHODS
2 .1 Water Analysis
2 . 1 . 1 Collection and Storage of Water
A l l containers used for c o l l e c t i o n and transport of water
were soaked i n 10^ hydrochloric acid for at least three hours
and repeatedly washed i n d i s t i l l e d water before use to ensure
freedom from contamination. Water samples were collected
from the main current of the stream, just below the surface,
( i ) Water for cation analysis was allowed to stand for at
l e a s t 10 minutes i n a 21 polythene beaker to allow
large suspended p a r t i c l e s to precipitate. •Total'
samples of about J>0 cnP were transferred to a 70 x 25 nmi
snap-top glass specimen tube. 30 cm^ 'nuclepore' samples
were obtained by f i l t e r i n g water through a Swinnex - 25
f i l t e r f i t t e d with a 25 mm diameter'Nuclepore* poly-
carbonate membrane, pore si z e 0 . 2 ^ . Acid-washed d i s
posable p l a s t i c syringes were used to force water through
the f i l t e r s with 25 cm^ of d i s t i l l e d water and 10 cm^
. of stream water being passed through and discarded
i n i t i a l l y . This s i z e of pore provides a better separation
of suspended materials from dissolved or complexed metals
than f i l t e r s with a larger pore s i z e , say O.k^jm which
may allow passage of some clay-size p a r t i c l e s (Kennedy,
Zellweger and Jones 1974) , Both ' t o t a l ' and 'nuclepore'
samples were a c i d i f i e d by the addition of one drop of
Aristar-grade concentrated n i t r i c acid.
- 19 -
( i i ) Water for anion analysis was f i l t e r e d through an acid-
washed No. 2 'Sinta' glass funnel i n to a 21 polythene
beaker. Three samples of 200 cm^ of f i l t e r e d water were
collected i n r i g i d screw-top polythene bottles. Water for
phosphate analysis wa^ collected i n a bottle impregnated
with iodine to prevent ba c t e r i a l a c t i v i t y prior to
ana l y s i s .
Samples were kept cool i n an ice-box u n t i l return to
the laboratory. Cation samples were stored at and
anion samples deep frozen u n t i l analysis was carried out.
A fliiEiL sample of water was collected i n a polythene
bottle, capped underwater to exclude a i r , and returned
to the laboratory i n the ice-box for immediate
determinations of pH, optical density and e l e c t r i c a l
conductivity (2.1.2, 2.1.5, 2.1.6).
Single samples of water were taken for each analysis since
the c o e f f i c i e n t of variation within s i t e i s well within
acceptable s t a t i s t i c a l l i m i t s (Leeder 1972).
2.1.2 Environmental Parameters
( i ) £H was measured i n the f i e l d using a Pye Unicam 293
portable pH meter and i n the laboratory using am E.I.L . 23A
direct-reading pH meter.
( i i ) Temperature was recorded i n the f i e l d using a standard
laboratory thermometer.
( i i i ) Total a l k a l i n i t y , e3q)ressed as mg 1 CaCO^, was determined
i n the f i e l d using the potentiometric f i l t r a t i o n technique
recommended by the American Public Health Association
(1971).
- 20 -
( i v ) Optical density mes^urements at wavelengths 420 nm,
240 nm and 254 nm of 'nuclepore' f i l t e r e d samples were
measured on a TJvispek spectrophotometer i n 4 cm c e l l s .
(v) -1 E l e c t r i c a l Conductivity was measured i n ^ mho cm on an E.I. L . portable conductivity bridge,Model ^ C - l , MkV.
( v i ) Water flow was estimated at each v i s i t on a f i v e point
sca l e , 1 = low flow 5 = high flow.
2.1.3 Cation Analysis
A l l analysis for Cations was completed on a Perkin-Elmer 403
atomic absorption spectrophotometer. Lead and cadmium were
analysed using the Tm sampling boat procedure (Kahn et al.l968)
to allow low l e v e l s of these elements to be determined. Zinc
and iron were analysed using a standard aspiration technique
and calcium and magnesium were determined by standard aspiration
technique a f t e r addition of standard amounts of lanthanum
chloride (Perkin-Elmer manual 1971)*
2.1.4 Anion Analysis
NH -N, NO -N, N02~' POi^-P were analysed using the methods
described by Stainton et al.(l977), colorimetric determinations
being carried out on a Tlvispek spectrophotometer i n 4 cm c e l l s
at the appropriate wavelength. Calibration was by preparation
of f i v e standards i n the concentration ranges of each anion.
- 21 -
i . NH -N reaction of ammonia with 5-1000 ug l " ' ' 0.01,0.0^,0.10,0.20 6h3 nra phenol and hypochlorite under al k a l i n e conditions to _^ form indophenol blue 0.50jig 1
i i . NO -N reduction by copper-cadmiiim 0.01,0.05,0.10,0.20 couple to n i t r i t e , NO_-N „ „ ^-1 (See below) ^O^/g ±
i i i . NO -N determination by formation 1-500jigl 0.001,0.002,0.OO^f im of pink-azo dye 0.005,0.01 ;zg l " ' ' •
i v . PO^-P reduction by acid-molybdate 5 - 250 _^ 0.01,,0.02,0.05_., 885 nm and ascorbic acid to form 1 0.10,0.20 ug 1 a blue complex
2.2 Plant Analysis
2.2.1 Collection and Storage of Plant Samples
Samples of plants to be analysed were collected i n 50 x 15nim
acid-washed p l a s t i c specimen tubes, four replicates for each
sample from suitable areas within the s i t e .
Scapania undulata grows i n dense tufts attached to rocks by
rhiz o i d s . Healthy 1 cm t i p s of submerged material were
collected, washed i n stream water to remove large sediments
and returned to the laboratory i n an ice-box, where they were
washed i n d i s t i l l e d water. As a general principle washing was
kept to a minimum to prevent excessive leaching out of metals,
although Jupp (unpublished data) finds l i t t l e leaching of
zinc from Scapania iindulata when allowed to stand i n d i s t i l l e d
water for two days - 3.k% a f t e r one day and a further 0.9??
aJter two days.
- 22 -
Hygrohypnum ochraceum grows on rocks at the side of the stream and on exposed rocks i n the main flow. I t s pleurocarpous habit traps much s i l t but 1 cm t i p s collected and washed as for Scapania shoots proved to be free of s i l t .
Dichodontium pellucidum growing on rocks exposed at low and
medium flows only shows healthy growth a f t e r submergence
following heavy r a i n . 1 cm t i p s were collected and washed
as for Scapania.
Batrachospermum sp. grovs submerged i n fast flowing water
attached to sandstone rocks. The attachment organs were
removed completely during laboratory washing and only
healthy growth analysed. I t proved s i l t free and the easiest
species to prepare for digestion.
Lemanea f l u v i a t i l i s specimens were always free of s i l t . 2 cm
t i p s were removed and washed.
Mougeotia sp. and Stigeoclonium tenue filaments r e t a i n
inorganic and organic debris which was removed as far as
possible by dissecting out filaments on an acid-washed
ceramic t i l e using s t a i n l e s s s t e e l instruments.
After washing, sainples were dried i n acid-washed snap-top
specimen tubes at 105°C for 48 hours. The time elapsing before
drying was kept as short as possible, and was never more than
eight hours, to prevent l o s s i n weight due to respiration
(Baker et al.l964). After drying samples were transferred to
a desiccator to cool before weighing to four decimal places.
- 23
2.2.2 Digestion and Analysis of Plant Material
( i ) Digestion was carried out by transferring as much dried
material as possible from each specimen tube to an acid-
washed 100 cm" Kjeldahl f l a s k . 5 cm" of A r i s t a r -
grade concentrated n i t r i c acid was then added to the
specimen tubes to wash out any dry matter adhering to the
sides of the.tube and any c e l l contents released on to
the bottom of the tube, caused by the rupture of c e l l s
during the drying process. In most cases about five
minutes was long enough to loosen any dried plaint
remains and the n i t r i c acid was transferred to the
Kjeldahl f l a s k . Two washings of the tubes with the
minimum of d i s t i l l e d water completed the transfer of
material and the tubes were then dried at 105°C, cooled
i n a desiccator and re-weighed to four decimal places
to determine the dry weight of plant material. Digestion
was c a r r i e d out by boiling for 30 minutes, when the diges"
was transferred to a 25 cm" volumetric flsisk and made up
to volume with d i s t i l l e d water, transferred to acid-
washed siiap-top specimen tubes and stored at 4°C u n t i l
a n a l y s i s . At each session of acid digestion two blanks
of n i t r i c a cid were included.
( i i ) Analysis for zinc was caxried out by atomic absorption
spectrophotometry using an acid r e s i s t a n t nebuliser for
aspiration. A l l samples required further dilution before
accurate determinations could be made.
- 24
2.3 Choice of s i t e s and sampling programme
Table 2.1 i s a l i s t of the s i t e s sampled, numbered 1 - 6 on f i g . 1.4.
The stream and reach numbers refer to the c l a s s i f i c a t i o n system held
i n the Botany Department, Durham University. Each reach number refers
to a s p e c i f i c stretch of the stream being 'that part of the main"
current of a stream t y p i c a l l y with a length of exactly 10m and never
exceeding t h i s length, with approximately the same quantity of vfater
leaving i t as entering i t ' . (Say 1978).
S i t e s were selected on the basis of water samples collected on
reconnaisances early i n Vlay 1978.
S i t e 1 on South Grain, represents an upland area free of any mining
influences. ( F i g . 2.1a).
S i t e 2 i s situated below old mine t a i l i n g s . ( F i g . 2.1b)
S i t e 3 i s below Grove Rake mine and old mine a d i t s . ( F i g . 2.2a)
S i t e 4 below the fluorspar washing plant and settlement pools and
Redburn Mine.(Fig. 2.2b)
S i t e 5 below the sewage treatment plant. (Fig. 2.3)
S i t e 6 above the entry of Rookhope Burn i n to the River Wear.
Two other c r i t e r i a were used i n deciding on s i t e s :
( i ) they should allow sampling of the s i x s i t e s to take place
during a single day
( i i ) they should coincide with, or r e l a t e closely to data pre
viously collected by workers from the Botany Department
Durham University, and available on computer f i l e .
More detailed s i t e descriptions are given i n Appendix A,
Samples of water and plant material were taken on s i x occasions
between Ifeiy and July 1978: l8th >fey, 1st June, 15th June, 27th June,
7th July, 17th July.
oo lA a\ v£) rA o
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SOUTH GRAI' J
Fiff. 2,1 (a) Soutli Grain at s i t e one.
(b) Upper Eookhope Burn looking downstream toi'/ai'ds s i t e two, Groye Rake Mine can be seea i n the distance.
F i g . 2.2 (a) Eookhope Burn looking dovmstream from S i t e three.
(b) Rookhopo Burn looicing ipstrean froa Site four. The fluorspar V/ashiag Plant can be seen i n the backe-round.
F i g . 2 . 3 Rookhope Burn l o o k i n g dovv-nskreani from S i t e '
fo u r . The banks can be seen to be w e l l
covered with v e g e t a t i o n i n t h i s lovier reach.
- 25 -
2,k F l o r i s t i c Survey
During the ccnirse of the sanrpling programme a b r i e f f l o r i s t i c survey-
was c a r r i e d out t o g i v e some idea o f the range o f submerged and emergent
plaint species present i n the stream.
2.5 Transplant Experiment
2.5-1 Marking and t r a n s p l a n t i n g o f Scapania undulata
Three s i t e s . designated A, B and C (Table 2-2) were chosen i n
upper Rookhope where populations of Scapania undulata were
growing i n obviously healthy c o n d i t i o n . Early analyses had
shown these s i t e s t o have marked diff e r e n c e s i n l e v e l s o f Zn
i n p l a n t t i s s u e . At each of the three s i t e s , three rocks were
selected from beneath the sizrface of the stream i n the main
cu r r e n t which had good growths of Scapania attached t o them.
Two shoots on each stone were marked 5 n™ behind the growing
p o i n t by t y i n g l e n g t h s o f r e d thread around the shoot. Bocks
were marked w i t h t h e i r s i t e o f o r i g i n w i t h red p a i n t . One
rock was l e f t a t i t s s i t e of o r i g i n and the other two t r a n s
p o r t e d i n a bucket c o n t a i n i n g stream water t o the other two
s i t e s . Rocks were replaced i n the main current of the stream
v r i t h the Scapania shoots submerged, ( F i g . 2-k). Samples o f
Scapania from each rock were placed i n p r e v i o u s l y l a b e l l e d
p l a s t i c bags and returned t o the l a b o r a t o r y i n an ice-box f o r
a n a l y s i s .
2.5.2 E s t i m a t i o n o f c h l o r o p h y l l a
The method used f o r c h l o r o p h y l l e x t r a c t i o n was t h a t o f
Lorenzen (I967) p r e v i o u s l y employed on Scapania by Duncker
(1976). C h l o r o p h y l l a was e x t r a c t e d i n 93% methanol i n sealed
McCartney b o t t l e s a t 70°C i n a covered water bath f o r 20
minutes. Ten shoots o f Scapania were broken up i n t o small
F i g . 2.Jl- _Scs;pania_ t r a n s p l a n t i n p o s i t i o n i n upper Eooldiope Burn.
(Follov/infj the t a k i n g o.i t h i s photograph the rock was t r a n s f e r r e d to a p o i n t i n the stream w h e r e , i t was f u l l y submerged.
- 26 -
fragments, but not ground and a second e x t r a c t i o n w i t h 95^ methanol proved necessary t o complete the removal of c h l o r o p h y l l . E x t r a c t s were f i l t e r e d through 2h mm Whatman G/FC 9 glass m i c r o f i b r e papers and made up t o 10 cm" . The e x t r a c t s were analysed on a Perkin-Elmer 'f02 scanning spectrophotometer i n cm c e l l s . Absorbance was read between 590 nm and 750 nm at the p o s i t i o n of maximum absorbance CX max 665 nm). Each sample was then a c i d i f i e d w i t h one drop o f IN su l p h u r i c a c i d , shaken f o r ten seconds and the absorbance re-read.
C a l c u l a t i o n was by a p p l i c a t i o n of the equations devised by
Jferker (1972) and the r e s u l t s expressed as the r a t i o
pheophytin a / c h l o r o p h y l l a + pheophytih a.
c
CHAPTER 3 - RESULTS
3.1 Water Analysis
The r e s u l t s of the c a t i o n analyses completed f o r the s i x sample
dates from May t o J u l y are shown i n Appendix B. 'To t a l ' and
'nuclepore' samples are included and a student's ' t ' t e s t c a r r i e d
out f o r each s i t e . Weak s i g n i f i c a n t differences' (p<0,10) are found
f o r zinc a t s i t e s one and fo u r and f o r cadmium at s i t e two. I r o n
shows weakly s i g n i f i c a n t d i f f e r e n c e s (p 0.10) at three s i t e s , t w o ,
f i v e and s i x (see 3.1.3)* I n folioi,idng sections 'miclepore' water
samples are r e f e r r e d t o except where otherwise s t a t e d .
3.1.1 Heavy metal c a t i o n s •
Table 3-1 shows the mean l e v e l s o f zinc, l e a d and cadmium
oc c u r r i n g a t the s i x sampling s i t e s . Means of 'nuclepore'
samples are shown on a l o g a r i t h m i c p l o t ' ( F i g . 3 . I ) where i t
can be seen t h a t zinc increases by two orders of magnitude -1 —1
from s i t e two t o s i t e three (O.O39 mg 1 t o I . 6 7 8 mg 1 ) .
A smaller increase between the same s i t e s i s also observed -1 -1 f o r cadmium (0.0012 mg 1 t o 0.0022 mg 1 ) . The maximum
value f o r l e a d however occurs a t s i t e four (0.093 ng 1 ) •
When means of a l l sample s i t e s a t each c o l l e c t i o n (Table 3»5)
are displayed g r a p h i c a l l y ( F i g . 3.2) concentrations o f zinc
i n the stream can be seen t o be an order of magnitude greater
than l e a d at each c o l l e c t i o n and two orders of magnitude
gr e a t e r than cadmium, w i t h cadmium showing the l e a s t f l u c t u
a t i o n over time.
, 3»1»2 Levels o f maj^or ca t i o n s
Table 3.3 shows the mean l e v e l s o f calcium, meignesium and i r o n
o c c u r r i n g a t the s i x s i t e s . Means of 'nuclepore' samples are
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F i g . 3 .1 V a r i a t i o n i n mean l e v e l s of Zn, Pb and Cd i n 'nuclepore'
v.'ater samples at sampling s i t e s .
20 , 40 sample interval (days)
F i g . 3 . 2 V a r i a t i o n i n mean l e v e l s , of Zn, Pb and Cd i n 'nuclepore'
water samples over sampling progsarame
1 - 28 -
shown on a l o g a r i t h m i c p l o t ( F i g . 3 . 3 ) . Levels of calcium . 7
Jt^jyy^^^ 'said magnesium show s i m i l a r p r o f i l e s , marked increases occurring ^ between s i t e s one and three. The major sources of these two 1
[ elements are the limestone rocks through which drainage waters
run i n the upper catclunent area. Calcium r i s e s from 5--,2^ "ig 1 ' -1 ' <S mg 1 between s i t e s one and three but then f a l l s to 1 -1
^ mg 1 at s i t e s i x . This d i f f e r e n c e between the two
elements between s i t e s f o u r and s i x may be r e l a t e d t o the
i n f l u e n c e of the washing p l a n t i n re l e a s i n g calcium i n t o the
water ( 1 . ? ; 3 . 1 . 3 ) .
I r o n shows a d i f f e r e n t p r o f i l e w i t h highest l e v e l s a t s i t e =1
one of 1 .32 mg 1 f a l l i n g sharply t o s i t e three t o reach a l e v e l of 0.31 mg 1 , then more slowly t o record a minimum
-1
l e v e l a t s i t e s i x of 0.21 mg 1 . This would suggest highest
l e v e l s of n o n - f i l t r a b l e i r o n o ccurring i n the s l i g h t l y a c i d
waters d r a i n i n g o f f the peat i n the upper reaches of the
catchment. I r o n forms a s i g n i f i c a n t p a r t of the dry matter of
m u l t i c e l l u l a r p l a n t s (100 j i g g dry matter; Stout 1971) and
would be expected t o be released i n greater concentrations
'^j than a t r a c e element such as zinc (Zn^ug g dry matter) by
decaying v e g e t a t i o n .
Means of a l l saniple s i t e s a t each c o l l e c t i o n (Table 3* 5
F i g . 3 . if) again shows the s i m i l a r i t y i n the behaviour of
calcium and magnesium w i t h an increase i n both during the
f i r s t 28 days followed by a f a l l a t fO days and a subsequent
• r i s e i n the f i n a l stages o f the survey. Estimates of water
f l o w ( 3 . 3 , Table 3 . 2 , F i g . 3 . 8 ) i n d i c a t e a f a l l i n discharge
d u r i n g the f i r s t p e r i o d o f the survey and the r e l a t i o n s h i p o f
f l o w t o l e v e l s o f cations i s included i n Chapter kl
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sampling F i g . 3 . 3 V a r i a t i o n i n mean l e v e l s of Ca, Mg and Fe i n water
a t sampling s i t e s .
TABLE J>-h MEAN LEVELS OF Ca, Mg AND Fe IN WATER ON SIX SAMPLING DATES IN ROOKHOPE BURN CATCHMEI J ( m g l " \ NUCLEPORE SAMPLES).
Sample Date Ca Mg Fe
18/V78 21.'fO 3.81 O.^if
1/6/78 30.83 5.73 O.ifO
15/6/78 'f2.28 7.62 O.ifif
27/6/78 25.3^ i f . 80 0.63
7/7/78 28.88 i f . 78 0.58
17/7/78 'f2.28 7A3 O.^if
TABLE 3 -3 MEAN LEVELS OF Fe IN 'TOTAL'AND 'NUCLEPORE' —— • — SAMPLES AT COLLECTION SITES (mg 1 )
Sampling S i t e T o t a l Nuclepore
1 1.68 1.32
2 0.90 0.70
3. 0.59 0.31
if 2.32 0.30
3 0.62 0.29
6 0.39 0.21
o 0
F i g .
' • 20 40 . sample interval (cjays)
V a r i a t i o n i n mean l e v e l s of Ca, I'lg and Fe i n v/afcer
over sampling progratnme.
60
o — — — p 2 3 4
sampling site 6
•Fig. 3.5 V a r i a t i o n i n mean l e v e l s of Fe i n ' t o b a l ' and ' 'nuclfipoce' vjater samples.
- 29 -3.1 .3 The r e l a t i o n s h i p between ' t o t a l ' and 'nuclepore' samples
Although no very s i g n i f i c a n t d i f f e r e n c e s are observed
between ' t o t a l ' and • nuclepore' samples over the period of the
survey ( 3 . I ) c o n s i d e r a t i o n of the mean l e v e l s of i r o n a t the
s i x s i t e s (Table 3*5; F i g . 3*5) shows a d i s t i n c t i o n i n the
l e v e l s o f the element at s i t e f o u r where the ' t o t a l ' sample -1 2
has a mean concentration of 2.52 mg 1 (5 = 22.8) while the -1 2
'nuclepore' sample has a concentration of O.3O mg 1 (.3 = 0 .02) .
Closer examination of i n d i v i d u a l samples (Appendix B) reveals
t h i s t o be l a r g e l y a r e f l e c t i o n o f the samples c o l l e c t e d on
17th J u l y 1978 when ' t o t a l ' zinc a t s i t e four was 12.25 mg l""^ -1
while 'nuclepore' zinc was 0.2^ mg 1 . These samples were
c o l l e c t e d below the washing p l a n t at a time when the settlement
pools were discharging i n t o the stream which became v i s i b l y
laden w i t h c o l l o i d a l and suspended m a t e r i a l . Examination of the
l e v e l s of other cations a t t h i s date and s i t e also reveals
l a r g e d i f f e r e n c e s f o r zinc ( ' t o t a l ' I .38 mg. 1 ; 'nuclepore'
0.22 mg l " ' ' ) , l e a d ( ' t o t a l ' 6 . I 6 mg l " ' ' ; 'nuclepore' 0 . l8'f -1 -1 ~1
mg 1 ) and calcium ( ' t o t a l ' 8 4 . 0 mg 1 ; 'nuclepore' 55*3 mg 1 X
The process of adding f e r r o u s sulphate and lime t o the settlement
pools (1 .7) w i l l c l e a r l y account f o r the elevated l e v e l s o f i r o n
and calci i i m , but since the process i s intended t o p r e c i p i t a t e
heavy metals i t does not account f o r the r a i s e d l e v e l s o f
f i l t r a b l e zinc and le a d . 3 .1 .4 Anion Analysis
Table 3 . 6 , F i g . 3 .6 show the mean l e v e l s of NO -N, NH^-N
and PO -P o c c u r r i n g a t the s i x s i t e s over the sampling p e r i o d .
NH^-N and NO -N can be seen t o be a t s i m i l a r concentrations i n
stream water but w i t h c o n t r a s t i n g l e v e l s at i n d i v i d u a l s i t e s .
- 30 -
NH^-N shows i t s raaxirnura value (0.2'f'f mg 1 ) at s i t e one which i s s u p p lied by drainage waters r i c h i n decomposition products o f peat from the upper catchment. Levels f u r t h e r downstream are lower w i t h a minimum of 0.1'f^ mg 1 occurring at s i t e f o u r .
The p r o f i l e f o r NO -N shows an increase from a minimum value -1 -1
a t s i t e one of O.O98 mg 1 t o 0.17 + mg 1 at s i t e three.
S i t e f o u r i s lower, which can be r e l a t e d t o the lower
p r o d u c t i v i t y above the reach. Sites f i v e and s i x show the -1
highest concentrations w i t h a maximum of 0.331 1 which can
be r e l a t e d t o the presence of the sewage p l a n t above s i t e f i v e
and increased a g r i c u l t u r a l a c t i v i t y i n the.lower reaches. A de c l i n e i n l e v e l s o f PO -P over the f i r s t f o a r s i t e s from a
-1 -1 maximum a t s i t e two of O.17 mg 1 t o O.OO9 mg 1 at s i t e four
i s f o l l o w e d by an increased concentration at s i t e s f i v e and
s i x t o a maximum l e v e l o f O.OI9 mg 1 r e l a t e d t o the e f f e c t s
of the sewage treatment p l a n t .
An observed increajse i n p r o d u c t i v i t y of the stream at s i t e s
f i v e and s i x can be r e l a t e d i n p a r t to the r a i s e d l e v e l s o f
PO^-P and NO -N a t these s i t e s .
Table 3.7j F i g . 3.7 shows mean l e v e l s of anions a t a l l sample
s i t e s a t each c o l l e c t i o n . The p r o f i l e s f o r NO -N and PO -P
are broadly s i m i l a r and can be r e l a t e d t o water f l o w through the
course o f the study (3.3). O v e r a l l l e v e l s of PO -P at each
c o l l e c t i o n are an order o f magnitude lower than NO -N and
but the p r o p o r t i o n a l changes occurring are s i m i l a r , there being
a t h r e e f o l d d i f f e r e n c e between maximum and minimum l e v e l s of
NO -N (0.098 mg l""^ t o 0.331 mg l " ' ' ) , a t w o - f o l d d i f f e r e n c e i n
TABLE 3-6 MEAN LEVELS OF ANIONS IN WATER AT COLLECTION SITES IN - 1 ROOKHOPE BURN CATCHMENT (mg 1 ANION; sem = 1 STANDARD ERROR)
Sampling S i t e NO -N NH -N PO; -P
X sem X sem X sem 1 0.098 0 . 0 2 4 0.244 0.042 0.016 0.003
2 0.135 0.057 0.153 0.016 0.017 0.005
3 0.174 0.037 0.171 0.020 0.015 0.002
4 . 0 . 1 4 1 0.033 0 . 1 4 4 0.012 0.009 0.002
5 0.252 0.033 0.163 0.012 0.017 0.001
6 0.331 0.065 0.150 0.008 0.019 0.003
TABLE 3-7 MEAN LEVELS OF ANIONS IN WATER ON SIX SAMPLING DATES IN ROOKHOPE BURN CATCHMENT (mg 1 ^)
Sample. Date NO -N NH^-N PO -P
18.5.78 0.154 0.161 0.0179
1.6.78 0.106 0 . 112 0.0116
15.6.78 0.150 0.193 0.0160
27.6.78 0.319 0.157 0 . 0214
7.7.78 0.219 0.188 0.0172
17.7.78 . 0.182 0.235 0.0095
TABLE 3-8 . MEAN pH, TEMPERATURE, TOTAL ALKALINITY, ELECTRICAL CONDUCTIVITY AND OPTICAL DENSITY OF WATER AT SAMPLING SITES I N ROOKHOPE BURN CATCHMENT
Sampling S i t e pH
Tempera t u r e ( °C) (mgl
T o t a l A l k a l i n i t y CaCO^) (jL
E l e c t r i c a l C o n d u c t i v i t y mho cm" 10^)
O p t i c a l Density (1cm path)
420nm 254nm 240nm
1 6.9 10.1 7.0 0.7 0.068 0.530 0.564
2 7.2 13.2 37.0 1.6 0 . 024 0.326 0.428
3 7.5 15.3 53.6 3.7 0.011 0.105 0.186
4 8.0 15.1 72.1 3.5 0.008 0.083 0.091
5 7.9 15.5 68.6 3.9 0.006 0.091 0.100
6 8.1 13.8 8 4 . 3 3.8 0.010 0.097 0.103
o
NO -N -3
NH -N
z
c O c
O. 6
o o-6 2 1 3 4 sampling site
5 6
F i g . 3.6 • V a r i a t i o n i n l e v e l s of anions i n water at sampling s i t e s .
o
E
NO - N
PO.-P
o 0--OO 20 . 4 0
sample interval (days)
Fig.. 3.7 V a r i a t i o n i n l e v e l s of anions i n water over saiupliag prograDMo,
60
Q.
n IT QJ
3
sample interval (days) F i g . 3.8 VariabioQ i n Zn i n v/ater, vrater'flow and discharge
over sampling programme.
(discharge
- 31 -
-1 -1 PO^-P (0.009 rag 1 t o 0.019 mg 1 ) and only j u s t l e ss than t w o - f o l d f o r NH^-N (O.l^f^f mg l"'' t o O.Zkh mg l " ' ' ) .
3.2 Water Flow
Estimates of water f l o w f o r the sampling dates are included i n
Table 3»2 and are shown as a histogram i n F i g . 3 « 8 . During the f i r s t
t h r e e c o l l e c t i o n s flows i n the streajn f e l l from a medium-high flow
ih) to a medium low f l o w (2) as a r e s u l t of a continuous dry s p e l l
l a s t i n g beyond 13th J u l y I978 (28 days). At the time of the f o u r t h
sample ihO days) f l o w had r i s e n t o medium-high (k) f o l l o w i n g heavy over
n i g h t r a i n and sample f i v e (5O days) was a high flow (5) follovidng
e i g h t days of prolonged r a i n . I n t e r m i t t e n t r a i n between days ^0 and
60 l e d t o a medium-high f l o w (k) a t the f i n a l sample date (60 days).
The r e l a t i o n s h i p between f l o w and l e v e l s o f cations and anions w i l l be
discussed i n the f i n a l chapter.
Late i n the p r o j e c t discharge l e v e l s from the Northumbrian Water
A u t h o r i t y monitoring s t a t i o n at Eastgate became a v a i l a b l e (Appendix D)
and these are r e f e r r e d t o i n the discussion. Mean l e v e l s of water flow
(m s ) are included on F i g . 3 . 8 .
3 .3 Environmental parame ters
Table 3.8 shows mean values of pH, temperature, t o t a l a l k a l i n i t y ,
e l e c t r i c a l c o n d u c t i v i t y and o p t i c a l d e n s i t y at each s i t e during the
sampling programme. F i g . 3 .9 shows v a r i a t i o n i n mean values of pH,
t o t a l a l k a l i n i t y and e l e c t r i c a l c o n d u c t i v i t y . Both a l k a l i n i t y and
c o n d u c t i v i t y show maximum values downstream i n d i c a t i n g an increase
i n the t o t a l o f d i s s o l v e d substances i n the water as sub s i d i a r y
streams j o i n Eookhope Burn, At the f i r s t s i t e pH i s 6.9 i n d i c a t i n g
the presence o f s l i g h t l y a c i d waters running o f f the peat of the upper
f e l l s , but any pronounced e f f e c t i s probably ameliorated by water
r u n n i n g over limestone rocks ( 3 . 1 . 2 ) .
X I f )
1
2 3 r 6
F i g . 3.9
4 ^ • sampling site
V a r i a t i o n i n pH a l k a l i n i t y and e l e c t r i c a l c o n d u c t i v i t y at sampling s i t e s ^
3" 4 sampling site
F i g . 3.10 V a r i a t i o n i n o p t i c a l density at sampling s i t e s .
- 32 -V a r i a t i o n i n o p t i c a l d ensity ( F i g 3.10) shov/s mciximum l e v e l s i n water running o f f peat i n the uppermost reach on South Grain. The l e v e l . 0,068 f o r a 1 cm path l e n g t h at 420 nm i n d i c a t e s the presence i n the water of humic m a t e r i a l s which i s supported by o p t i c a l d e n s i t i e s of 0.530 and 0.564 at 254 and 240 nm r e s p e c t i v e l y i n d i c a t i n g high l e v e l s of organic m a t e r i a l s g e n e r a l l y . I n lower reaches where i n f l u e n t water flows over l e s s peaty m a t e r i a l l o w e r l e v e l s are observed. Site s i x shows a r i s e which can be r e l a t e d toVthe greater p r o d u c t i v i t y of the stream and surrounding v e g e t a t i o n and consequent increase i n decomposition products a t lower reaches of the stream.
Temperature shows an increase from s i t e s one t o f i v e which i s r e l a t e d
t o both a l t i t u d i n a l e f f e c t s and to the r a t e of flov; i n the stream, i n
the lovrer reaches f l o w being slower and the stream wider al l o w i n g a
greate r heating e f f e c t from s o l a r r a d i a t i o n . The lower temperature
a t s i t e s i x can be r e l a t e d t o the shading by the t r e e s growing on the
banks of the stream i n t h i s reach.
3 .4 P l a n t a n a l y s i s
3.4.1 Concentration of zinc i n species sampled
The r e s u l t s o f the p l a n t analyses are shown f o r the species
sampled i n Tables 3 . 9 j i - v , together w i t h the l e v e l o f zinc i n
water sajnples c o l l e c t e d a t the time. Means are c a l c u l a t e d from
f o u r r e p l i c a t e s except where otherwise noted. Enrichment r a t i o s
are included f o r each sample. Where samples were c o l l e c t e d
from two s i t e s Student's ' t ' t e s t s have been performed on l e v e l s
o f zinc i n p l a n t and i n water and are included i n the t a b l e .
Means + 1 standard e r r o r o f z i n c i n p l a n t s and water are
recorded f o r each s i t e .
TABLE 3-9 ( i ) - (v) LEVELS OF Zn IN 'fflJCLEPOfiK* WATER &^MPLES ( Z n ^ AND PLANT MATERIAL (Zn^) AND ACCJMITLATION RATIOS FOR SPECIES SAMPLED (x = MEAN ± 1 sem)
( i ) Zinc accumulation i n Scapania undulata (1 cm t i p s )
S i t e Stream Number
Reach Number
Stream Name
0219 75
Zn w-1
mg 1 South Grain 0.022
0.020
0.033
0.019
0.039
0.02^
' % -1
69
67
75
3h
71
67
Enrichment Ratio
3136
3350
2272
28if2
1821
2792
0.026 - 0.003 67.17 - 2.9
0012 15 Rookhope Burn
0.0if5
0.028
0.032
0.053
0.062
0.103
369
35^
678
369
233
359
8200
126if3
21188
6962
3758
3 ^ 5
= 0.039 - 0.007 393.67 - 61
0012 30- Rookhope Burn
1.30
2.60
1.28
* 7295 5612
1862
H 1
't» - t e s t . S i t e s 1 arid 2 Zn^ Zn w
t = 5.37 , P< 0.001
t = 1.707 , N.S.
Zn = mean o f h r e p l i c a t e s except * spot samples only. P
( i i ) ZINC ACCUMULATION IN HIGROHYPNUM OCHRACSUM ( l cm TIPS)
S i t e Stream Reach Stream Number Number Name
Zn w
, -1 mg 1
P -1
/ g g
Enrichment Ratio
2 0012 - 15- Rookhope Burn
0.0k3
0.028
3^2
369
7600
12179
0.032 274 8563
0.053 315 5943
0.062 287 4629
0.103 460 4466
X 0.039 - 0.007 341.17 - 27.70
5 0012 - ' t l Rookhope Burn
0,h6
0.26
9912
4584
21548
17631
0.37 6049 16349
0.72 6859 9526
0.52 9310 17904
• 0. 13 6244 14521
X = 0 . 4 6 - 0.063 7159 - 836.57
' t ' - t e s t . S i t e s 2 and 5 Zn t = P
8.1if6; p<0.001
Zn t = w 6.642; p^O .001
( i i i ) ZINC ACCUMULATION IN DICHODONTIUM PELLUCIDUM (1 cm TIPS)
3 0012 - 30 Rookhope Burn
1.37
2.22
24624
9850
17974
4437
^ Zn^ = mean o f 4 r e p l i c a t e s
( i v )
S i t e
ZINC ACCUMULATION IN LEMANEA FLUVIATILIS (2 cm TIPS)
Stream Number
Reach Number
Stream Name
Zn w
'nuc' mg 1 -1
'Zn
/g 1 -1
Enrichment Ratio
0012 - 46 Rookhope Burn
x =
0.191
0.191
0.34
0.34
0.178
1793
2647
2353
1303
2046
0.248 - 0^03^ 2028.4 - 211.14
9387
13859
6921
3832
11494
(v) ZINC ACCUMULATION IN THREE ALGAE (WHOLE SPECIMENS)
Species S i t e stream .Number
Reach Number
Stream Name
Zn 'nuc' mg 1
^Zn •P -1
J i g g
Enrichment ratio
Batrachospernum 2 0012 - 15 Rookhope 0.045 2464 54756 sp. Burn 0.028
0.032
0.053
O.O62
0.103
805
863
460
287
315
28750
26969.,
8679
4629
.3058
X = 0.054f0.011 865.67 - 334.71
Stigeoclonium tenue
4 0012 - 38 Rookhope Burn
0.66 6313 9565
Mougeotia 4 0012 - 38 Rookhope 0.94 1363 1450 sp. Burn 0.51 13689 26841
5 - 41 0.37
0.72
8818
1148
23832
1594
6 - 46 0.191 7832 41005
Zn = iBeah of 4 r e p l i - c a t e s . P
- 33 -
( i ) Scapania undulata
At the two s i t e s where Scapania was growing profusely
s i g n i f i c a n t l y lower mean l e v e l s ( t - 5.37; p< 0.001) of
zinc are found i n p l a n t m a t e r i a l at the s i t e of lower zinc
l e v e l s i n water, even though diff e r e n c e s i n water are not
s i g n i f i c a n t ( t = I .7O7). This i s discussed i n r e l a t i o n t o
the existence of d i f f e r e n t s t r a i n s of the bryophyte i n the
f i n a l chapter (4 .2) .
The spot samples from s i t e three although showing higher
concentrations of zinc i n p l a n t m a t e r i a l (564^g g t o
7295 Jig g dry weight) show lower enrichment r a t i o s than
samples from s i t e two but i t must be remembered t h a t
samples were not r e p l i c a t e d and were subject t o only
p e r i o d i c inundation a t high f l o w s . I t vfas also noticed
t h a t the growth of Scapania from s i t e three was less robust
than a t s i t e s one and two and 1 cm t i p s c e r t a i n l y
i n c l u d e d some dead m a t e r i a l . L i t t l e r e l i a n c e can therefore
be based on these samples.
( i i ) Hygrohypnum ochraceum
Samples of the bryophyte obtained from s i t e s two and
f i v e show a s i g n i f i c a n t d i f f e r e n c e ( t = 8.1.46; p<0.00l)
i n c o n c e ntration o f zinc i n t i s s u e . Levels at s i t e f i v e
are very high having a mean value of 7159.67 + 836.5'^g g
dry weight while a t s i t e two much lower l e v e l s are recorded, - 1
mean zinc concentration being 3 4 1 . 1 7 + 27 .70Jig g dry
weight. When considering enrichment r a t i o s , those a t
s i t e two are seen t o be s i g n i f i c a n t l y lower ( t = 4.185;
P < 0 . 0 1 ) , 7397 + 1331 a t s i t e two compared w i t h 16246 + l 6 4 2
a t s i t e f i v e . However the standard e r r o r o f each i s high
- 34 - • and not too much should be read i n to the difference.
( i i i ) Dichodontium pellucidum
Samples of the bryophyte were obtained from s i t e three on
only two collections when flow was medium-high, plant
material only being f u l l y submerged on one of these _ 1
occasions (5O days) when a concentration of 24264jUg g
dry weight was recorded. On the second occasion (6O days)
the bryophyte was growing as an emergent species and a
much lower l e v e l ( 9 8 5 0 j a g g dry weight) was recorded, even
though the l e v e l of zinc i n water was much higher (2.22 - 1 - 1
mg 1 compared to 1 .37 mg 1 ).
( i v ) Lemanea f l u v i a t i l i s
Samples of the eilga were collected from s i t e s i x on
fi v e occasions. At 14 days the alga was overgrown with
epiphytic species and proved impossible to clean. A
mean concentration of 2 0 2 8 . 4 + 2 1 1 . l 4 j i g g dry weight
was recorded with a range of enrichment ratios from
3832 to 13859 .
(v) Whole specimens of the three algae Batrachospermum sp.,
Stigeoclonium tenue and Mougeotia sp. show a wide range
of concentrations of zinc. Batrachospermum has a - 1
mean l e v e l of 8 6 8 . 6 7 + 3 3 4 . 7 1 J^g g dry weight with a
range of 287 - 2464 jig g dry weight. Such a
v a r i a b i l i t y , with high concentrations of zinc i n plant
t i s s u e ( 2 4 6 4 Jig g dry weigh^at r e l a t i v e l y low l e v e l s of
zinc i n water ( 0 . 0 4 5 mg 1 ) and low concentration of zinc —1 "•
( 3 1 5Jig g dry weight) at high l e v e l s i n water (O.IO3 mg 1 ^
- 35 -
suggests that the use of t h i s species i s somewhat un
re l i a b l e i n r e f l e c t i n g levels i n water which may be
related to the large amounts of mucilage present around
the filaments affecting uptake of ions from the water,
Stigeoclonium tenue was present at only one collection
at s i t e four with a high concentration of 6313 g dry
weight.
Mougeotia sp., l i k e Stigeoclonium, was a transient species
occurring at three s i t e s i n t e r m i t t e n t l y . I t occurred i n
shallows out of the main flow of the stream and was found
to accumulate high concentrations of zinc, ^^hSjig g
dry weight to 13689jig g dry weight.
3.^.2 Relationships between species and sites
Fig. 3.11 i s a scatter diagram of the concentrations of zinc
i n plant tissue and l e v e l of zinc i n water for the species
collected. A roughly l i n e a r relationship i s seen to exist ^ -1 -1
between .the two from 0.02 mg 1 to about O.3 mg 1 of zinc
i n water. The species included i n t h i s range are a l l
permanent submerged members of the stream community,
Scapania undulata, Hygrohypnum ochraceum, Lemanea f l u v i a t i l i s
and Batrachospermum sp. Mougeotia sp. seems to be somewhat
variable. At lower levels (O . I9I - O.51 mg 1 zinc) i t
conforms to the l i n e a r relationship, but at higher levels
(0.72 and 0.9^ mg 1 zinc) lower concentrations i n plant
material are recorded. A sim i l a r s i t u a t i o n exists i n the
specimens of Scapania undulata, Dichodontium pellucidum and
Stigeoclonium tenue sampled at high levels and there i s a
suggestion of a plateau occurring i n the. relationship. This
0-01
Fig. 3.11
0-1 - 1 1 0
log Zn • in water (mg r^)
Scatter diagram to show relationship betv/een zinc content of plant material and 'nuclepore' level of zinc for species sampled.
Key
o •
s
^4EH11;'^ iindjVLata. HygroiiN'pnum oclaraceurn BatracliospermuTn sp.
Lemane_a fl}ivi_a'-.ilis Dichodoatium pellucidum Mougeotia sp. Stincocloniu.m tenue
log Zn in water (nng I"')
Fig. 3 . 1 2 .Scatter diagram to show relationship between zinc content of plant material and 'nuclepore' l e v e l of zinc f o r s i t e s sampled.
Key
o
Site 1
2
3
h
3
6
- 36 -
may be related to uptake mechanisms for cations reaching a
saturation l e v e l i n plant tissue.
When levels of zinc i n plants and water are plotted according
to the sites from which they were collected i n that stream
(Fig. 3«12) a clustering can be seen to exist at sites one,
two, f i v e and s i x at which lower levels of zinc are present
i n water.
At sites with higher levels of zinc (three and four) a greater
v a r i a b i l i t y i s seen to e x i s t .
Fig, 3*13 i s a scatter diagram of the enrichment ratios plotted
against levels of zinc i n water at the collection sites for the
species sampled. I f a l i n e a r relationship exists for uptake
of zinc at di f f e r e n t levels of zinc i n the surrounding medium
then a horizontal trend would be expected. Although v a r i a b i l i t y
can be seen to be great thiis i s i n general true for levels -1
of zinc up to about 0.^ mg 1 zinc i n ivater. At higher
levels a doxmward trend i n the d i s t r i b u t i o n can be observed
indicating that at these elevated levels less zinc i s being
accumulated. . r
J- / * Linear regressions/were calculated for two groups of plant
/ /, 9 species. For all'species sampled the regression equation i s
y = khOO x + 1395, r = + 0.52^. When only Scapania undulata,
Hygrohypnum ochraceum and Lemanea f l u v i a t i l i s are considered,
omitting data f o r transient algae and bryophytes subject to only
periodic inundations the regression equation i s y = I3887 x + 303
T 'r + 0.893. The increased correlation coefficient suggests
that the three species forming permanent submerged populations
w i l l be more r e l i a b l e i n r e f l e c t i n g levels of zinc i n water.
O 0 1 0 1 1 1 0
log Zn in water (mg r'')
Fig. 3 .13- Scatter diac-ram to shov; relationship betv/eon enrichme-rr. r a t i o s and 'nuclepore' level of zinc for siDecies sampled.
Key * _Scapania. undulata o Hygrohypnum ochraceum * Batrac'iospormum sp-+ Lemanea i l u v i a t i l i s
X Dichodentium pellucidum
* StigeocloniuTTi tetiue
- 37 -
^• 5 F l o r i s t i c _s_urvey
Table 3-10 shows the species found growing i n Rookhope Burn and i t s
t r i b u t a r y . South Grain, during,the months of May, June and July 1978.
Not a l l species were growing profusely and so were not available for
heavy metal analysis. There are no species which have not previously
been reported from streams with elevated levels of heavy metals
although Lloyd (1977) reports Fontinalis antipyretica as being absent
from Rookhope Burn. Most plants have a re s t r i c t e d d i s t r i b u t i o n
certainly of areas where they grow profusely.
( i ) Bryophytes
Scapania undulata, although showing the widest d i s t r i b u t i o n
occurring at four of the s i x s i t e s , only grew well i n South Grain
and upper Rookhope Burn. Isolated populations were found at sites
three and four. I n si t e s one and two i t forms dense carpets of
submerged and emergent growth attached to sandstone rocks on the
bed of the stream. Hygrohypnum ochraceum occurs at three si t e s ,
but profusely at only sites two and f i v e , ^fost populations are not
continuously submerged being attached to sandstone boulders i n
mid stream. Dichodontium pellucidum grows as patches attached to
s i l t wedged between rocks. I t i s a small form of the moss,
1 - 1.5 cm t a l l and i s exposed to the a i r for much of i t s l i f e .
I n medium-high f l o w s . i t i s submerged and was only sampled f o r
heavy metals analysis at those times. Hygrohypnum luridum,
Fontinalis antipyretica and Hygroamblystegium f l u v i a t i l e were
observed as isolated populations i n reaches f i v e and s i x .
( i i ) Algae
Lemanea f l u y i a t i l i s grows submerged, attached to limestone blocks
i n s i t e s i x . Growth i s dense with occasional overgrowth of
epiphytic species. Batrachospermum sp. grows well i n s i t e two
TABLE 3.10 RESULTS OF FLORISTIC SURVEY OF SUBMERGED PLANTS IN THE STJDY AREA
BRYOPHYTES ^ ^ 3^^*^lf 5 6
* Scapania undulata (L.) Dum. vK/ \X/ >/ 'J
* Hygrohypnum ochraceum (Turn, ex Wils) Loeske. \/J >Jy/ v/
* luridum (Hedw.) Jenn, J
* Dichodontium pellucidum (Hedw.)Schp. y/
Fontinalis antipyretica Hedw. \/
Hygro_amblystegium f l u v i a t i l e (Hedw.) Loeske. \/ y/
ALGAE
* Eatrachospermam sp.
* Lemanea f l u v i a t i l i s (L.) Ag. vC/
* Stigeoclonium tenue Kutz. vC^
* Mougeotia sp. ^ vC^ \/
Ulothrix sp. y/ v/
Spirogyra sp. v/ \/
Hormidium sp. v/ \/
Microspora sp. \/ y/
* Used i n plant analyses
y// growing profusely
^ present
- 38 -
attached to sandstone rocks and was continuously submerged during the course of the sampling programme. Stigeoclonium tenue and ^fougeotia sp. both show periods of dense growth, Stigeoclonium gx'owing attached to sandstone boulders i n s i t e four at one [ col l e c t i o n and Moug^eotia. growing i n shallows subject to periodic inundations with water from the main current. The remaining algae, TJlothrix sp. ,Spirogyra sp., Hormidium sp. and Microspora sp. grow i n communities dominated bt Mougeotia sp.
3.6 Transplant exp^rirrient 1
( i ) The results of measurement of growth of shoots of Scapania undulata '
are presented i n Table 3-11 as me;ans of the new gro\rth of ten
/ shoots (nra) and percentage increase i n length. A chi-squared
test was carried out = ^O.Oif; p<D.00l) indicating a significant .
\ difference i n the gro\rth of transplanted shoots. Growth i s
greatest (3.90^ nm; 78^) i n control shoots at s i t e C and least i n
shoots transplanted from s i t e B to s i t e A. (I.OO nm; 20^).
Differences i n the other sites were less marked. The amount of
branching occurring during the experiment (* = number of shoots
showing branching) was also greatest i n control s i t e C. No
branching was observed i n any of the shoots originating from Site A.
( i i ) Chlorophyll a/pheophytin a ra t i o s are shown i n Table 3-12 expressed
at pheophytin a/chlorophyll a + pheophytin a. Student's ' t '
l\_ s t a t i s t i c s for pairs of r a t i o s on different dates i s O.O8O (N.S.)
suggesting no difference exists due to the transplant treatment. i
However, i t i s noticeable that shoots from s i t e A generally contain
a greater proportion of chlorophyll a than the shoots from ;
s i t e s B and C and that t h i s difference i s maintained a f t e r trans- j
plantation. Scapania growing i n the uppermost regions i s 1
noticeably more robust and healthy with less sediment attached to i t
TABLE 3 - 1 1 GROWTH OF MARKED SHOO'TS OF SCAPANIA UNDULATA AT TRANSPLANT SITES
RECIPIENT SITE
DONOR. SrTE
A
B
C
MM)
2.60
1.00
2. +0
%
32
20*
f8*
B
MM
2.89
2.13
.2.78
37.8
if2.6*
53.6**
MM
2.92
3.20
3.90
%
58. if
M.O*
78.0***
* = number of shoots showing branching
"X? = ^+0.04; p < 0.001
TABLE 3 - 1 2 CHLOROPHYLL a/PHEOPHYTiN a RATIO IN MARKED SHOOTS OF SCAPANIA UroULATA PPRESSED.AS THE..RATIO PHEOPHYTIN, a/ CHLOROPHYLL a + PHBOPHYTIN a
DONOR SITE B
RECIPIENT SITE A B
19/6/78 0.157 0.192
17/7/78 0.160 0.086
19/6/78 0.073 0.ff27
17/7/78 0.121 0.613
19/6/78 0.590 0.if95
17/7/78 0.525 0.if30
C 0.138
0.l6if
0.678
0.535
0.331
0.327
t = 0.080, NS
/
n
TABLE 3-13 LEVEL OF Zn (^g g"^ DRY WEIGHT) IN SCAPAm UNDULATA AND IN WATER AT TRANSPLANT SITES (mg l"^ 'nuc' sample)
i . SCAPANIA UITOULATA
DONOR SITE B
I I . WATER
RECIPIENT SITES A B C
19/6/73 69.76 73.68 72.9 + 17/7/78 58.if5 198.6 + 125.32
1V6/78 586i27 191.82 519.11 17/7/78 386.6 + 315.16 527.66
19/6/78 639.63 728.35 696.21 17/7/78 '+23.58 698.22 582.77
t = OA3, N.S.
A B C 19/6/78 0.012 0.035 0.03 +
17/7/78 0.02 + 0.039 0.0 +0
- -'9 -
than at the lower s i t e s .
( i i i ) Concentrations of zinc i n plants (ug g dry weight) and le v e l s
i n water (mg 1 ) for cunlruls and transplants are displayed i n
Table 3 - i 3 » Student's ' t ' s t a t i s t i c for concentration of zinc
A i n Scapania shoots shows no si g n i f i c a n t difference (t = 0.^3)
due to the transplant treatment but i n general i t can be noted
that Scapania transplanted from low to higher zinc l e v e l s i n
water show an increase i n zinc concentration (e.g. transplant from
A — i B; 73.68 —^198.6^ Jig g dry weight) and transplants to s i t e s
with lov/er zinc l e v e l s show a decrease i n zinc concentration
(e.g. transplant from B —^A; 586.27 — ^ J>86.6kjig g dry
weight).
The most interesting feature hov/ever i s that despite the fact that
l e v e l s of zinc i n water at a l l three s i t e s d i f f e r very l i t t l e ,
Scapania from s i t e A has consistently lovrer l e v e l s of zinc than
either of the other two s i t e s , even after transplation for 37 da^ys
of the experiment.
3.7 Correlation analysis
An intervariable correlation analysis was completed for the mean l e v e l s
of 16 variables i n water during the sampling programme presented i n
Table 3-1^- While correlation analysis with a small number of samples
( n = 6) i s not s t a t i s t i c a l l y very meaningful i t serves to indicate which
factors may be in t e r r e l a t e d and which opposed. I t does not suggest
caused^elationships and a more elaborate programme of sanipling and
more sophisticated s t a t i s t i c a l analysis such as p r i n c i p l a l component
analyses would be required. The r e s u l t s of the analysis are presented
i n the form of a matrix i n Table 3-15»
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- 40 -Zinc shows a s i g n i f i c a n t positive correlation with cadmium (p-c^O.Ol) but a weak correlation with lead. This w i l l be related-to the sources of these metals i n the catchment (4.1). Although not s t a t i s t i c a l l y s i g n i f i c a n t , quite large negative correlations are found between a l l three heavy metals and A l l measures of optical density, estimating organic material i n the water, and t h i s w i l l be related to chemical
,/ f (speciation of the cations (4.1.4). Negative correlations are seen
befwefen the heavy metals, lead and cadmium, and i r o n which w i l l be
discussed i n r e l a t i o n to the adsorptive effect of hydrated iron oxides.
Significant negative correlations of i r o n with calcium ( r = - 0.972,
P<0.01) and magnesium ( r - - O.96I, p O.OI). / l/^Vv" A •
Calcium and magnesium show a strong positive correlation with each
other ( r = O.98I, p<0.00l) which can be related to t h e i r co-occurrence
i n limestone rocks(4.1.2) and as would be expected they show positive
correlatioas with pH (Ca, r = 0.943, p 0.01; Mg, r = 0.876, p^O.05)
and t o t a l a l k a l i n i t y (Ca, r = O.965, p 0.001; % , r = 0.904 p<0.05).
I n both cases calcium shows the stronger correlation and appears to be
making the greater contribution being present i n greater concentrations
i n water (Table 3-3, 3-4). Strong negative correlations are seen with
a l l measures of o p t i c a l density which w i l l be related to the formation
of organic complexes. (4.1,4). A strong positive correlation (p<0.00l)
shows with e l e c t r i c a l conductivity indicating the contribution made by
these cations to the t o t a l solute concentration of the water.
Ir o n and NH -N are p o s i t i v e l y correlated (p<t) .05) which i s related to
the common source of these factors. Negative correlations of i r o n with
pH (p<0.05) and t o t a l a l k a l i n i t y (p< 0 . 0 l ) can be related to pre
c i p i t a t i o n effects of increased a l k a l i n i t y and water hardness. (4,1',5).
Strong positive correlations are seen with a l l measures of optical
density (p< 0 . 0 l ) which can be related to the chelating effects of
1
- 4 1 -
humic materials.
POji -P and NO -N show a positive correlation with each other (N.S)
and PO^-P i s negatively correlated with NH -N (N.S).
Strong s i g n i f i c a n t negative correlations are observed between both
pH (p< 0 . 0 3 ) and t o t a l a l k a l i n i t y (p^ 0 . 0 5 ) and a l l measures of
opt i c a l density indicating the acid soft nature of the water draining
off the peat i n the upper catchment.
Positive correlation with both calcium ( p ^ O.O5) and magnesium
(p 0.01) and temperature can probably be related to s o l u b i l i t y effects
but the strong negative correlation with iron (p< 0 . 0 l ) and measures
of opt i c a l density are probably explained by a l t i t u d i n a l effects and
the rate of flow of the streajn along i t s length.
CHAPTER 4
DISCUSSION
The present study i s subject to the d i f f i c u l t i e s of interpretation inherent
i n a l l short-term, l i m i t e d scale sampling programmes but raises some
int e r e s t i n g points regarding uptake of a heavy metal by plant species and
these w i l l be discussed i n r e l a t i o n to the use of plants as monitors of
levels of zinc i n the aquatic environment.
4.1 Water Chemistry
' t . l . l Sources of heavy metals i n Rookhope Burn
- 7 The low background levels of heavy metals recorded at s i t e one
i n the present study are higher than those occurring i n up
land streajns i n non-mining areas i n the United Kingdom which
are i n the range 0.002 to 0.01 mg l"'' (Whitton and Say 1975).
Leeder (1972) quotes levels i n the River Tweed i n a non--1
mineralised region of 0.002 to 0.006 mg 1 i n the months of
A p r i l to June 1976. Ifejor increases i n zinc and cadmium occiir
above s i t e three i n the present study (3.1.1) suggesting that the
run-off from old mine t a i l i n g s i n the upper reaches of Rookhope
Burn are contributing l i t t l e to levels i n water and the
main sources would appear to be the active fluorspar mines
and drainage from the mine a d i t s . Say (1977) quotes figures
from Tailrace l e v e l (NY 917428) of zinc i n water over the year
1972 - 75 varying from 7.6 to 9.0 mg 1 and from data held
on the computer f i l e at the Botany department, Durham
University, a figure of 6.15 mg 1 of zinc i s recorded f o r
Viaduct Hush (NY 925430). Both of these sources are adits
draining old mine workings and must contribute s i g n i f i c a n t l y to
levels i n the main stream even a f t e r d i l u t i o n . The high
- 43 -
c o r r e l a t i o n between ziac and cadmium found i n the present
study ( 3 . 8 ) suggest a s i m i l a r source f o r cadmium, Say (1978)
- 1
r e p o r t i n g a l e v e l of O.OI7 mg 1 from Tailrace Level. This
agrees w i t h the f i n d i n g s of Leeder (1972) who suggests t h a t
the washing p l a n t c o n t r i b u t e s l i t t l e to ra i s e d l e v e l s of zinc i n
Eookhope Burn.
Maximum l e v e l s of lea d are found below s i t e four {J).^.^)•
where the major i n f l u e n c e w i l l be the a c t i v i t i e s a t the
washing p l a n t . The highest l e v e l o f lead recorded in'nuclepore'
water samples i n the stream during the survey was on the f i n a l
sampling date ( 3 . 1 . 3 ) » During t h i s time e f f l u e n t was being
discharged from the settlement pools and c l e a r l y they are the
major c o n t r i b u t o r s t o elevated lead l e v e l s i n the stream.
I n t e r f e r e n c e e f f e c t s between le a d and cadmium are found by
Say (1977) t o increase zinc t o x i c i t y i n species of Hormidium
dur i n g l a b o r a t o r y t o x i c i t y t e s t s and the co-occurrence of these
two elements a t elevated l e v e l s of zinc at s i t e four may w e l l
account f o r the absence of any permanent f l o r a a t t h i s s i t e
( 3 . 6 ) .
Levels o f a l l heavy metals f a l l below s i t e f o u r suggesting l o s s
of metals from water by p r e c i p i t a t i o n , adsorption and d i l u t i o n .
The d i f f e r e n c e s recorded i n l e v e l s of zinc i n ' t o t a l ' and
'nuclepore' samples ( 3 . 1 » 3 ) although not s t a t i s t i c a l l y
s i g n i f i c c i n t w i l l have an e f f e c t on accumulation since soluble t
forms are taken up/to higher l e v e l s / t h a n are c o l l o i d a l or /
p a r t i c u l a t e forms.
- 44 -
k.^.Z The r o l e o f major c a t i q j i s aad the_speciation of heavy me_tiL cations
The high l e v e l s of cations of calcium and magnesium recorded
i n the lower reaches o f Rookhope Burn ( 3 . 1 . 2 ) i n d i c a t e the
hard calcareous and a l k a l i n e nature of the water. The
an t a g o n i s t i c e f f e c t o f calcium on heavy metal cations reported
by Jones (1958) may a f f o r d some p r o t e c t i o n t o p l a n t m a t e r i a l from
the e f f e c t s o f zinc accumulation. Say and Whitton (1977) ind
t h a t increased concentrations of both calcium and magnesium
reduce the t o x i c i t y o f zinc t o l a b o r a t o r y populations of
Hormidium_ sp. and propose a hypothesis of calcium competing w i t h
zinc f o r uptake s i t e s i n the p l a n t .
The r o l e of i r o n i n reducing the pool of heavy metals a v a i l a b l e
t o the p l a n t may be s i g n i f i c a n t . I r o n oxides and hydrous oxides
are i n c r e a s i n g l y p r e c i p i t a t e d i n hard a l k a l i n e waters and at the
pH values observed i n t h i s study the adsorptive p r o p e r t i e s of
metal hydroxide on t o sediments i s high. Furstenau ( l 970)
r e p o r t s maximal adsorption of i r o n species on t o quartz at
pH 2~J>. This increase i n p r e c i p i t a t i o n o f hydrous oxides of
i r o n w i t h t h e i r strong c a t i o n exchange mechanisms (Williams et a l
197'l-) w i l l remove hydrolyzable metal by adsorption. Increase
i n pH w i l l enhance t h i s e f f e c t .
Jenne (1968) proposes t h a t the hydrous oxides of i r o n smd
manganese f u r n i s h the p r i n c i p a l c o n t r o l on the f i x a t i o n o f
zinc i n freshwater sidements. I n the lov;er reaches of the
stream where the e f f l u e n t from the settlement pools exerts i t s
i n f l u e n c e ( 1 . 7 , 3»1«3 ) i then the high l e v e l s of c o l l o i d a l and
p a r t i c u l a t e i r o n present w i l l c e r t a i n l y p l a y a r o l e i n
removing heavy metals from s o l u t i o n .
- 4 5 -
^ .1 .3 The r o l e of anions in_zijic_accunMlation
The low l e v e l s of anions (Table 3-6) are c h a r a c t e r i s t i c of
upland streams. The increase i n NO -N and PO -P below s i t e s
f i v e and s i x are probably r e l a t e d t o the e f f e c t s of the sewage
treatment p l a n t and an open d r a i n at Eastgate together w i t h
r un off from a g r i c u l t u r a l l a n d. The preence of PO -P i s
reported t o reduce the t o x i c i t y o f zinc t o p l a n t s (Say et a l
1977) , but the major e f f e c t of the anions i s l i k e l y t o be one
^ o f reduced p r o d u c t i v i t y of the stream waters.
^ . l . ' f The r o l e o f organic complexes
Amongst soluble species of metals the r o l e of conrplexing and
c h e l a t i n g agents appears important. B o l t e r and Butz (1976)
r e p o r t n a t u r a l organic acids from decaying l e a f l i t t . e r ^ n c r e a s e
the s o l u b i l i t y of heavy metal compounds by an increased com
p l e x f o r m a t i o n i n the presence o f soluble organic a c i d or
f u l v i c a c i d and suggest t h a t i n c r e a s i n g pH increases the
•y f o r m a t i o n of complexes \d.th f u l v i c a c i d . The high l e v e l s of
humic m a t e r i a l s seen i n the upper reaches i n the present study
(Table 3-8) w i l l increase the pool of a v a i l a b l e metals by
forming organic coniplexes. Complexing by humic acids i s r e
p o r t e d t o reach a maximum at pH 8.5 (Randhawa and Broadbent
1965)1 and Bondarenko (1972) r e p o r t s calcium humates as being
most s t a b l e a t n e u t r a l o i j a l k a l i n e pH values. At the pH.values
r e p o r t e d i n the present study humic m a t e r i a l s v / i l l p l a y a r o l e
i n the upper reaches i n s o l u b i l i s i n g z i n c . The r o l e of f u l v i c
a c i ds i s complicated by the r e p o r t by Bondarenko (1972) o f
calcium f u l v a t e s being more s t a b l e or low pH values.
- 46 - •
^ . 1 . 5 pH and temperature e f f e c t s
pH and temperate ;e w i l l have e f f e c t s on the s o l u b i l i t i e s
o f metals, and ph on the adsorptive p r o p e r t i e s of oxides and
hydrous oxides ( 4 . 1 . 2 ) . Increase i n pH and decrease i n
temperature r e s u l t i n reduced s o l u b i l i t i e s of metnls and
increase i n pH i s reported by Bachmann (196I) t o increase
uptake of Zn i n l a b o r a t o r y studies of freshwater algae.
Along the l e n g t h o f the stream increase i n pH i s accompanied
by increase i n temperature, but e f f e c t s such as the increasing
water hardness and t o t a l a l k a l i n i t y are probably moi'e
s i g n i f i c a n t .
4 .1 .6 Levels of flovf i n the stream
Flow c l e a r l y plays a p a r t i n c o n t r o l l i n g l e v e l s of dissolved
substances i n aquatic environments. I n general, l e v e l s of
metals are highest a t lowest f l o w s , agreeing w i t h the f i n d i n g s
o f Grimshaw et a l (1976) . They a t t r i b u t e t h i s inverse
r e l a t i o n s h i p t o a ' d i l ^ i t i o n ' e f f e c t w i t h a negative r e l a t i o n -
shi.p between discharge and concentrations o f zinc. The
r e l a t i o n s h i p i s however confused by ' f l u s h i n g ' , occurring when
storm r un o f f f o l l o w s heavy summer p r e c i p i t a t i o n . During
dry summer months, at elevated temperatures, o x i d a t i o n of
mineral ores can be presumed t o occur r e s u l t i n g i n r a i s e d
concentrations i n sources of heavy metals. The abrupt
le a c h i n g o f these metals a t such times w i l l l ead t o high
metal concentrations i n water r e l a t e d to high discharge.
C l e a r l y the present study goes no way towards p r o v i d i n g
i n f o r m a t i o n on t h i s aspect and a l o n g i t u d i n a l study such as
t h a t by Grimshaw et a l i s r e q u i r e d .
- 47 -
The r e l a t i o n between anions and discharge shows maximum l e v e l s of anions o c c u r r i n g a t maximum flows r e l a t i n g t o the d i f f e r e n t o r i g i n s of these substances.
k.Z Plant J f e t e r i a l
Of the p l a n t species sampled during the present study, three seem
t o present themselves as candidates f o r f u r t h e r consideration f o r use
as monitors of zinc l e v e l s i n water p o l l u t e d by mine drainage.
Scapania undulata, H^i^rohjgnura ochraceum and Lemanea f l u v i a t i l i s show
r e l a t i v e l y s t a b l e enrichment r a t i o s , at l e a s t w i t h i n c e r t a i n
environmental l i m i t s . They a l l occur as permanent members of the sub
merged populations o f the stream, are r e l a t i v e l y robust p l a n t s and do
not present great problems i n p r e p a r a t i o n f o r a n a l y s i s . Both S. undulata
and H. ochraceum have a f a i r l y broad d i s t r i b u t i o n along the stream
and work by Harding ( l 9 7 8)has shorn the p o t e n t i a l of L. f l u v i a t i l i s
f o r t r a n s p l a n t a t i o n t o areas o f elevated zinc l e v e l s i n upland streams
f o r a n a l y s i s o f zinc content a f t e r a s u i t a b l e exposure time. Lemanea
samples w i t h a zinc content o f 213J^S g dry weight were transplanted
t o a p o l l u t e d s i t e where sample^: shov;ed concentrations greater than
lOOOjig g dry weight. Subsequent a n a l y s i s of these transplanted - 1
samples revealed l e v e l s above 1 0 0 0jig g dry weight. Corresponding
decreases were observed i n r e c i p r o c a l t r a n s p l a n t s . Duncker (1976)
demonstrated t h a t t r a n s p l a n t s o f Scapania undulata l e f t i n s i t e s f o r
e i g h t weeks show s i m i l a r increases. The l i m i t e d t r a n s p l a n t a t i o n
experiment c a r r i e d out i n the present study shows a s i m i l a r t r e n d o f
increase a t s i t e s o f higher zinc l e v e l s i n water but perhaps a
longer e q u i l i b r a t i o n time i s needed f o r a more s i g n i f i c a n t r e s u l t .
I n general i t can be s a i d t h a t increased l e v e l s of zinc i n water are
c o r r e l a t e d w i t h increased concentrations i n p l a n t m a t e r i a l although
- 48 -
the v a r i a b i l i t y i s great. S. undulata shows r e l a t i v e l y high conti-nts
o f zinc a t s i t e s w i t h low l e v e l s . o f zinc i n water e.g. s i t e two, - 1 - 1
mean zinc concentration 393.67 Jig g dry weight w i t h 0,039 mg 1 i n - 1
water compared w i t h s i t e one, mean zinc concentration 67.17 Jig g i r y
weight w i t h 0.026 rag 1 i n water. McLean and Jones (1973) i n uptake
st u d i e s of 63 Zn i n Scapania show a general resistance t o heavy metals
and i t i s unfortunate t h a t r e p l i c a t e d samples f o r the brybphyte a t
higher zinc l e v e l s are not a v a i l a b l e from the present study. The
absence of Scapania a t such s i t e s may be r e l a t e d t o the preference of the species f o r s o f t a c i d i c waters. Say (1977) f i n d s Scapania i n waters
- 1
w i t h 10.53 mg 1 Ca Co^ and pH 3.8 - 6.8 growing attached t o a sand
stone or shale s u b s t r a t e . The lower reaches of Eookhope Burn have a pH
range of 7 .9 - 8 . 1 , a t o t a l a l k a l i n i t y o f 68.6 - 84 .3 mg 1 Ca Co^ and
limestone blocks forming the substratum. However a t the c o l l e c t i o n w i t h
the highest z i n c l e v e l ( s i t e t h r e e , 13 th June 1978, Zn = 2.6 mg 1 ) w
the c o n c e n t r a t i o n of zinc i n Scapania (4840 ug g dry weight) i s not
the highest content recorded suggesting some measure of r e g u l a t i o n of
zinc accumulation. This i s supported by the lower enrichment r a t i o s f o r
Scapania a t s i t e three ( 4 4 l - 36 I2 ) compared t o s i t e two (34S5 - 21188).
Although/the t r a n s p l a n t s t u d i e s r e p o r t e d here, nor those o f Duncker / l\
(1976) do not support the view t h a t d i f f e r e n t s t r a i n s of Scapania e x i s t
i t i s worth n o t i n g again t h a t populations of the bryophyte growing i n
water c o n t a i n i n g very s i m i l a r l e v e l s of zinc are markedly d i f f e r e n t i n
zinc c o n c e n t r a t i o n despite the presence at the uppermost s i t e of humic
m a t e r i a l s able t o complex w i t h zinc ions,and lower l e v e l s o f calcium
and magnesium. 4.3 R e l a t i o n s h i p t o other s t u d i e s
A number o f other s t u d i e s of zinc accumulation i n the mineralised area
of Weardale have i n c l u d e d the three species Scapania undulata,
Hygrohypnum ochraceum and Lemanea f l u v i a t i l i s . Results o f analyses o f
- 49 -
zinc i n p l a n t and water are presented i n Table 4-1 from the work of Leeder (1972) , Duncker (1976) , Lloyd (1977) and Harding (1978) . Despite d i f f e r e n c e s i n the methodology of water c o l l e c t i o n , p l a n t sampling and p l a n t d i g e s t i o n procedure discussed below, some general features do emerge.
The anomalous r e s u l t s obtained f o r Scapania undulata from s i t e one on
South Grain are s i m i l a r t o those obtained by other workers on North
Grain s i k e , another t r i b u t a r y o f Rookhope Burn. Concentrations o f zinc
i n p l a n t s are an order of magnitude lower i n these two streams compared
t o concentrations i n Rookhope Burn.
Concentrations of zinc i n Hygrohypnum ochraceum at s i t e s w i t h low
l e v e l s of zinc ( 0 .1 mg 1 ) water reported i n the present study range - 1 - 1
from 274 ug g dry weight t o 369 ug g dry weight. Harding r e p o r t s a concentration o f 334 ug g dry weight i n samples from the River
- 1 Derwent a t a water l e v e l o f 0.021 mg 1 .
At s i t e s w i t h water l e v e l s greater than 0.20 mg 1 p l a n t content - 1 - 1
ranges from 4384 ug g dry weight t o 9912 ug g dry weight i n the
present study. Reports from other workers are i n the range l438 ug g
dry weight t o l6480 ug g dry weight.
The r e s u l t s f o r Lemanea f l u v i a t i l i s from the present study range from - 1 - 1
1308 ug g dry weight t o 2647 ug g dry weight w i t h zinc l e v e l i n - 1
water g r e a t e r than 0 . 1 mg 1 i n a l l samples. Samples from other - 1 - 1
waters a t l e v e l s g r e a t e r than 0 .1 mg 1 range from 721 ug g dry _1
weight t o 2890 ug g dry weight.
Results then are of a s i m i l a r order of magnitude t o other workers but
there i s a great v a r i a b i l i t y from one study t o another making com
p a r a b i l i t y d i f f i c u l t . Enrichment r a t i o s i n Scapania undulata ranging
TABLE i f - 1 LEVELS OF Zn IN PLANTS (Zn g l"^ dry weight) AND WATER (Zn^, mg l" ' ' ) IN STUDIES IN THE MINERALISED ARE'V OF WEARDALE
SPECIES AUTHOR STREAM NAME Zn w
Zn , -1 - 1 Enrichment r a t i o •mg 1 _^g g
Scapania undulata Duncker North Grain 0.031 ; . 129 if 161 Scapania undulata (1976) Sike 0.126 '+52 5587
Lloyd North Grain 0.131 150 11if5 (1977) Sike 0.015 266 17735
Rookhope 0.100 2if50 2if500 Burn 0.030 3890 129667
Harding E.Derwent 0.021 771 3671if (1978) 0.272 2992 11000
Leeder Rookhope . 0.221 5256 23783 ochraceum (1972) Burn 6730 if5l68
0.077 if 109 53363
Lloyd Rookhope 0.030 3600 120000
(1977) Burn 0.100 if530 if5300
0.520 3960 7615
0.330 16^+80 'f9939
0.310 3500 11290
0 . 2 ^ 11790 49125
Harding R. Derwent 0.021 33^ 15905 (1978) 0.272 1if38 5286
Lemanea Leeder Rookhope 0.077 1197 155^5 f l u v i a t i l i s (1972) Burn 0 .1 if9 151^ 10161
Lloyd Rookhope 0.2kO 2890 120if2 (1977) Burn 0.310 1310 if226
Harding R. Derwent 0.021 1671^^ (I978) 0.272 916 3368
0.206 723 3510
( o l d t i s s u e ) (young t i s s u e )
- 50 -
irom 1143 t o 129667 ana m Hygrohypnun: ochraceiim from 4466 t o 120000 make ge n e r a l i s a t i o n s d i f f i c u l t . The major source of difference p a r t i c u l a r l y i n the o l d e r studies i s probably i n the sampling o f . p l a n t m a t e r i a l . I n the present study 1 cm t i p s of the bryophytes and 2 cm t i p s of the alga were removed. Other.- workers have used d i f f e r e n t standards or s p e c i f i e d samples as being of 'healthy growth'. Lloyd (1977) compares zinc concentrations i n O.3 cm sections o f Hygrohypnum ochraceum
and shows in c r e a s i n g concentration passing both from the t i p ( t i p : - 1 - 1
369+9 )ig g dry weight, O .3-I cm: 848+9 )ig g dry weight; 1.5-2.0 cm:
1857+ 78 >ig g"'' dry w e i g h t ) .
Other problems a r i s e from the water sampling technique used. The
f i l t e r e d samples from e a r l y s tudies i s equivalent t o the ' t o t a l ' sample
of the present study ( i . e . f i l t e r e d through a ' s i n t a ' glass f u n n e l ) .
I t has been shown i n the present study t h a t ' t o t a l ' l e v e l s of zinc can
be s i g n i f i c a n t l y higher than 'nuclepore' samples at some c o l l e c t i o n s
( 3 . 1 . 3 ) 3iiid the e f f e c t o f t h i s w i l l be t o reduce enrichment r a t i o s .
A t h i r d source o f d i f f e r e n c e i s i n the d i g e s t i o n procedure used. Leeder
(1972) uses a muffle furnace a t 500°C t o prepare samples, a technique
which i s reported by Zak (1966) t o l e a d t o low values i n the deter
m i n a t i o n o f metals. l i o y d (1977) i n comparing a number of d i g e s t i o n
processes f i n d s lower l e v e l s o f z i n c , l e a d and cadmiiun i n dry ashing
methods when compared t o wet d i g e s t i o n . Any r e d u c t i o n i n the apparent
zinc content of p l a n t m a t e r i a l w i l l again reduce the magnitude of the
enrichment r a t i o .
4 .4 P l a n t s as monitors o f zinc i n n a t u r a l waters
I t seems u n l i k e l y from the r e s u l t s o f the present "study t h a t p l a n t s can
be used t o monitor zinc a t higher l e v e l s i n water since t h i s requires
b o t h s t a b l e enrichment r a t i o s and a low v a r i a b i l i t y which are not
observed i n the species s t u d i e d . Reference t o F i g . 3 .11 and 3.12 shows
- 51 -
a plateau i n accumulation i n those species growing at elevated l e v e l s of z i n c, ^fost hypotheses of uptake discuss binding s i t e s f o r metals ( P i c k e r i n g and Puia 1969, McLean and Jones 1975, Say and Whitton 1977). These must be f i n i t e and, once satu r a t e d , uptake must be i n h i b i t e d . I n a d d i t i o n Dietz (1973) shows many bryophytes adsorbing manganese and i r o n e x t e r n a l l y . This i s a passive process and as such w i l l lead t o erroneous r e s u l t s f o r accumulation since i t i s not uiider the c o n t r o l o f the p l a n t . I f s i m i l a r e x t e r n a l adsorption occurs of zinc then there must be doubts about the use of bryophytes as monitors. The la r g e amount of mucilage secreted by algae such as Batrachospermum sp. may also play a r o l e i n t a k i n g up heavy metals e x t e r n a l l y .
Changes i n l e v e l s of zinc i n water may be r a p i d such as w i l l occur
f o l l o w i n g ' f l u s h i n g ' ( i f . 1.6) and p l a n t species should be able t o
respond t o these sudden increases. They must also be capable o f
i n t e g r a t i n g f l u c t u a t i o n s i n the normal l e v e l s of zinc so as t o r e f l e c t
a general l e v e l o f the metal.
The source of zinc t o a species used f o r monitoring l e v e l s i n water
should be the aquatic phase, of the environment. Rooted angiosperms
such as Mmulus g u t t a t u s reported i n a high , zinclevel.stream (Leeder
1972, Lloyd 1977) can be assumed t o be absorbing at l e a s t i n p a r t from
the substratum. Even the absorptive f u n c t i o n of the r h i z o i d a l system
of bryophytes may r e s u l t i n uptake of the p l a n t s ' metal intake from
sediments.
I f sampling i s t o take place throughout the annual cycle of a stream,
p l a n t s need t o be permanent members of the stream community and occur
i n s u f f i c i e n t abundance t o a l l o w repeated sampling. The t r a n s i e n t algae
observed i n the present study are u n s u i t a b l e f o r monitoring procedures.
S i m i l a r l y emergent species, or those subject t o p e r i o d i c inundations
such as Dichodontium pellucidum are also u n s u i t a b l e .
- 52 -
The sampling procedure i s r e q u i r e d t o be e a s i l y performed by non-
s p e c i a l i s t s , and the three species sampled c o n s i s t e n t l y , Scapania
undulata, Hygrohypnum ochraceum and Lemanea f l u v i a t i l i s , a l l proved
s a t i s f a c t o r y on those grounds.
The technique of t r a n s p l a n t i n g t o areas of raise d z i n c - l e v e l s must be
l i m i t e d by the n a t u r a l d i s t r i b u t i o n of the species and i n t e i ' p r e t a t i o n of
accumulation must be r e l a t e d t o the other p h y s i c a l and chemical para
meters of the stream. More i n f o r m a t i o n i s required i n r e l a t i o n t o the
s p e c i a t i o n o f metals i n n a t u r a l waters and the i n t e r a c t i o n w i t h com-
p l e x i n g and c h e l a t i n g molecules, synergism and antagonism of other
c a t i o n s .
The existence of t o l e r a n t s t r a i n s has been shown i n a number of aquatic
species ( 1 . 5 ) but the work of Duncker (1976) and the present study ( 3 . 6 )
f a i l t o provide evidence t h a t t h i s i s the case i n Scapania undulata.
I f t o l e r a n t s t r a i n s do e x i s t then l a b o r a t o r y studies are required t o
d i s t i n g u i s h them from non-tolerant forms and accumulation studies c a r r i e d
out such as those o f Duncker on Scapania and Harding (1978) on Lemanea
f l u v i a t i l i s .
The l i m i t e d data a v a i l a b l e from the t r a n s p l a n t experiment of the present
study regarding growth suggests t h a t more studies of growth r a t e s f o r
t o l e r a n t and non-tolerant s t r a i n s are required. I t may be t h a t
t o l e r a n c e i s c h a r a c t e r i s e d by a lower r e l a t i v e growth r a t e (Rnjax °^
Grime and Hunt 1975) enabling species t o survive i n conditions of heavy
metal s t r e s s . Comparability o f 1 cm or 2 cm t i p s o f p l a n t m a t e r i a l
r e f e r r e d t o i n 4 .3 may be rendered i n v a l i d by marked d i f f e r e n c e s i n
growth r a t e s of d i f f e r e n t s t r a i n s and f u r t h e r , whether the high contents
o f o l d e r t i s s u e s ( 4 . 3 ) i s a f u n c t i o n of time of exposure t o high zinc
- 53 -
l e v e l s or some f a c t o r such as general metabolic a c t i v i t y which could be r e l a t e d t o the age of the t i s s u e .
From the r e s u l t s of the present study and consideration of the r e s u l t s
^ ^ o f other authors a s t r a t e g y can be envisaged of employing a range of
bryophytes and algae such as Scapania undulata, Hygrohypnum ochraceum
and Lemanea f l u v i a t i l i s as monitors of zinc l e v e l s i n water. Uptake
needs t o be determined i n f i e l d and l a b o r a t o r y conditions using a
standardised methodology of permanent populations and tra n s p l a n t
specimens, and accumulation r a t i o s so determined i n t e r p r e t e d i n r e l a t i o n
t o chemical and p h y s i c a l parameters of the water. At highest l e v e l s
of zinc where a plateau of accumulation occurs i t could be used t o
i n d i c a t e a s a t u r a t i n g l e v e l of the metal i n water.
REFERENCES
Abdullah, M.T. and Royle,L.G. (1972) Heavy metal content of some r i v e r s and lakes i n Wales. Nature, Land. 2 3 « , 329.
American P u b l i c Health Association. (1971) Standard Methods f o r the Exami n a t i o n o f Water and Wastewater ( 13e ) . American Public Health A s s o c i a t i o n I n c, 1970, Broadway, New York, 87'+PP.
Antonovics, J. Bradshaw, A.D. and Turner, R.G. (1971) Heavy Metal Tolerances i n p l a n t s . I n : Craggs, J.B. (ed) pp. 1-^6. Advances i n Ecol. Res.7» 2 5 f p p . g
Bachraann, R.W. (I96I) Zinc i n studies of the freshwater zinc cycle. Proc. Symp. Radio-ecol. Colorado. 1 , ^^5-496.
Baker, D.E., Goseline, G.W., Smith, C.A., Thomas, W.I., Grube, W.E. and Ragland, J.L. .(196'f) • Techniques - f o r r a p i d analyses of corn leaves f o r eleven elements. Agron. J. 56, 133-136.
B o l t e r , E. and Butz, T.R. (1976) Proc. I n t e r n a t i o n a l Heavy Metals Conference I , 1975. Toronto, Canada.
Bondarenko, G.D. (1972) , quoted i n Williams, S.L., Aulenbach, D.B. and Clesceri, N.L. I n : Rubin, A.J. (ed) (197^) Aqueous - Environmental Chemistry of Metals. Ann Arbor Science Publishers I n c . , Michigan, 390pp.
Bowen, H.J.M. (1966) Trace Elements i n Biochemistry. Academic Press, New York, 2if1pp.
Boyd, C.E. and Lawrence, J.M. ( I967) The mineral composition of several freshwater algae. Proc. 2 0 t h . Ann. Conf., S. East Game and Fish Commsrs. 20,413-24
Brock, T.D. (I969) M i c r o b i o l growth under extreme conditions. Symp. Soc. gen. f a c r o b i o l . 19, 15-41-
Brooks, R.R, and Rumsby, M.D. ( I965) The biogeocheraistry of trace element uptake by some New Zealand b i v a l v e s . Limnol. Oceanogr. 10, 521-527-
Brown, D,H,, C a p p e l l i n i , R,A. and P r i c e , C.A. ( I966) Actinomycin D i n h i b i t i o n o f zinc-induced formation of cytochrome c i n Ustilago. Plant Physiol. 41, 1543-1546
Brysm, G.W. (1969) The absorption of zinc and other metals by the brown seaweed Laminaria d i g i t a t a . J. Mar, b i o l . Ass. U.K. 49, 225-243-
Carpenter, K,E. (1924) A study of the forms of r i v e r s p o l l u t e d by lead raining i n the Aberystwyth d i s t r i c t . Ann. Appl. B i o l . 11,1-23.
" (1925) On the b i o l o g i c a l f a c t o r s involved i n the d e s t r u c t i o n o f r i v e r - f i s h e r i e s by p o l l u t i o n due t o lead mining. Ann. Appl. B i o l . . 12, 1-13-
Cooke, J.A., Johnson, M.S., Davison, A.W. and Bradshaw, A.D. (1976) Fluoride i n p l a n t s c o l o n i s i n g f l u o r s p a r mine waste i n the Peak D i s t r i c t and Weardale. Environ. P o l l u t . V\_^ 9-25-
D i e t z , F. (1975) The enrichment r a t i o of heavy metals i n submerged p l a n t s . I n : Jenkins. S.H, (ed.) Advances i n Water P o l l u t i o n Research, 6th I n t . Conf. pp.55-62 Pergamon Press, Oxford, 946 pp.
Duncker, M. (1976) A study of Zinc-Resistance and Accumulation of Zinc i n Scapania undulata (L.) Dura. M,Sc. Ecology D i s s e r t a t i o n , Durham U n i v e r s i t y , 84 pp;
Dunham, K,C, ( I945) Geologv of the Northern Pennine O r e f i e l d . I . Tyne t o Stainmore. Mem. Geol. Surv, H.M.S.O,, Lond., 557pp.
Erapain, A. (1976) Les bryophytes aquatiques u t i l i s e s comme traceurs de l a cont a m i n a t i o n en metaux l o u r d s des eaux douces. Mem. Soc. Roy. Bot. Beig. 7 , 141-156.
Ernst , R., Allen,. H,E. and Mancy, K.H. (1975) C h a r a c t e r i s a t i o n of trace metal species and measurement of trace metal s t a b i l i t y constants by electrochemical techniques. Water Res. 9, 969-979-
Foster, P. (1976) Concentrations and concentration factors of heavy metals i n brown algae. Environ. Pollute 10, 45-53-
- 55 -Fuerstenau, D.W. (1970) quoted i n Leckie, J.O. and James, R.O. I n : Rubin, A.J.
(e d ) . (1974) Aqueous-Environmental Chemistry of Metals. Ann Science Publishers I n c . , Michigan, 390pp.
Goodman, G.T. and Roberts, T.M. (1971) Plants and s o i l s as i n d i c a t o r s of metals i n the a i r . Nature, Lond. 231, 287-292.
G r i f f i t h s , A.J., Hughes, D.E. and Thomas, D. (1975) Some aspects of mi c r o b i a l r e s i s t a n c e t o metal p o l l u t i o n . I n : Jones, M.J. (ed). pp 387-394. Minerals and the Environment. The I n s t i t u t i o n o f Mining and Metallurgy, 803 pp.
Grime, J.P. and Hodgson, J.G. (1969) An i n v e s t i g a t i o n of the ecological s i g n i f i c a n c e of l i m e - c h l o r o s i s by the means of large-scale comparative experiments. I n : Rorison, I.H. pp.67-99. Ecological Aspects of the Mineral N u t r i t i o n o f Plants. Blackwell S c i . Pub. Oxford.
" and Hunt, R. (1975) Relative Growth Rate: i t s range and adaptive s i g n i f i c a n c e i n a l o c a l f l o r a . J. Ecol. 63, 393-422.
Grimshaw, D.L., Lewin, J. and Fuge, R. (1976) ^Seasonal and short-term v a r i a t i o n s i n the concentration and supply of dissolved zinc t o p o l l u t e d a ^ ^ a t i c environments. Environ. P o l l u t . 1 1 , I - 7 . ^
Gullvag, B.M., Skaar, H. and Ophus, E.M."Tl974) An u l t r a s t r u c t u r a l study of lead accumulation w i t h i n leaves of Rhytidiadelphus squarrosus (Hedw.) Warnst. A comparison between experimental and environmental poisoning. J. Br y o l . 8 , 117-122.
Harding, J.P.C. (1978) Studies on Heavy Metal T o x i c i t y and Accumulation, i n the Catchment Area of the Derwent Reservoir. Ph.D. Thesis, Durham U n i v e r s i t y , 4 « 2 p p .
Hargreaves, J.W. LLoyd, E.J.H. and Whitton, B.A. (1975) Chemistry and vegetation o f h i g h l y a c i d i c streams. Freshwat. B i o l . ^ /-i- gc
Harvey, R.S. and P a t r i c k , R. (1967) Concentrations of Cs, Zn and Sr by freshwater algae. Biotech. Bioengng. 9., hh3-^%.
Hem, J,D. (1972) Chemistry and occurrence o f cadmium and zinc i n surface water and ground water. Wat. Resour. Res. 8 , 661-679.
Irukayama, K., Kondo, T., Kai,-F, and F u j i k i , M, (196I ) Studies on the o r i g i n o f the causative agent of Minamata disease. I . Organic mercury compound i n the f i s h and s h e l l f i s h from Minamata Bay. Kumamoto Med. J. 14,157-169.
Jenne, E,A. (1968) I n : Baker, R.A. (ed.) Trace Inorganics i n Water. Amer. Chem. Soc. Adv. i n Chem. Series 73 Washington D.C., 337pp.
Jones, J.R,E. (1940) A study of the z i n c - p o l l u t e d r i v e r Tstwyth i n n o r t h Cardiganshire, Wales. Ann. Appl. B i o l . 27, 367-368.
" (1958) A f u r t h e r study o f the z i n c - p o l l u t e d r i v e r Ystwyth. J. anim. Ecol . 27, 1-14,
Jones, A.N. and Howells, W,R, (1969) Recovery o f the r i v e r Rheidol, E f f l u e n t and Wat. Treat. J, 9 ,605-610.
Jowett, DI (196^) Population s t u d i e s on l e a d t o l e r a n t A g r o s t i s t e n u i s . E v o l u t i o n 18, 70-80.
J u r n i a k , J.J. and Inouye, T.S, ( I 962 ) Some aspects of zinc and copper phosphate f o r m a t i o n i n aqueous systems. S o i l S c i . Soc, Amer, Proc, 26, 144-147,
Kahn, H.L. Peterson, G.E. and S c h a l l i s , J.E. ( I 9 6 8 ) Atomic absorption microsampling w i t h the 'sampling'boat' ^..technique. Atomic Absorption Newsl e t t e r , 7 , 35-39.
Keeney, W.L,, Breck, W,G., Vanloon, G.W* and Page J,A. (1976) The determination o f t r a c e metals i n Cladophora glomerata: C. glomerata as a p o t e n t i a l b i o l o g i c a l monitor. Water J?es. 10, 98l~98?.
Kennedy, V.C,, Zellweger, W, and Jones, B,F, (1974) F i l t e r pore-size e f f e c t s on the a n a l y s i s o f A l , Fe, Mn and T i i n water. Water Resour. Res. 10 , 785-790.
Krauskopf, K.B. ( I 9 6 7 ) I n t r o d u c t i o n t o Geochemistry. McGraw-Hill, U.S.A., 721pp. Leeder, A.J. (1972) Studies on Lead and Zinc P o l l u t i o n i n an Upland Stream.
M.Sc. Ecology D i s s e r t a t i o n , Durham U n i v e r s i t y ,
- 5 . 6 -L i t t l e , P. and Martin, M.H. (1974) Biological monitoring of heavy metal
pollution. Environ. Pollut. 6, 1-19. Lloyd, E.J.H. (1977) Accumulation of Metals by Aquatic Plants i n the River Wear
System. Ph.D. Thesis, Durham University, 265pp. Lorenzen, C.J. (1967) Determination of Chlorophyll and pheo-pigments spectro-
photometric equations. Limnol.Oceanogr. 12, 543-346. Marker, A.F.H. (1972) The use of acetone and methanol i n the estimation of
chlorophyll a i n the presence of pheophytin. Freshwat. B i o l . 2, 56I-585 McNeilly, T. and Bradshaw, A.D. (1968) Evolution i n copper tolerant Agrostis
tenuis. Evolution 22, I O 8 - I I 8 . McLean, R.D. and Jones, A. 1X975) Studies of tolerance to heavy metals i n the
f l o r a of the r i v e r s Ystwyth and Clarach, Wales. Freshwat. B i o l . , 431-444.
Milikan, C.R. and Hanger, B.C. ( I965) Effgpts of chelation and of various cations on the mobility of foli a r - a p p l i e d -'Zn i n subterranean Clover, Aust. J.Biol, S c i . 18, 955-957.
% e r s , J . (1951) Physiology of the algae. Ann. Rev. Microbiol, , I 57 - I8O. Ondratscheck, K. ( l 9 4 l ) Uber den Mineralsalzbedarf heterotropher I l a g e l l a t e n .
Arch. Mikrobiol. j12, 241-255-Passow, H., Rothstein, A. and Clarkson,, J.W. (1961) The general pharmacology of
heavy metals. Pharmac. Rev. I 3 , 185-224. Perhac, R.M. (1974) Distribution of Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn i n dissolved
and p a r t i c u l a t e s o l i d s from two streams i n Tennessee. J . Hydrobiol. 1^, 177-186.
Perkin-Elmer (1971) Instruction Manual for tfodel 403 Atomic Absorption Spectrophotometer. Perkin-Elmer Corporation, Norwalk, Connecticut.
Pickering, D.C. and Puia, I . L . (I969) Mechanism for the uptake of zinc by Fon t i n a l i s a n t i p y r e t i c a . Physiologia P I . 22, 655-661.
Preston, A., J e f f e r i e s , D.F., Dutton, J.W.R., Harvey, B.R. and Steel, A.K. (1972) B r i t i s h I s l e s coastal waters: The concentrations of selected heavy metals i n sea water, suspended matter and bio l o g i c a l indicators - a p i l o t survey. Environ. P o l l u t . 5, 69-82.
P r i c e , C.A. ( I966) Control of processes s e n s i t i v e to zinc i n plants and microorganisms. I n : Prasad, A.S. (ed.) pp. 1-20, Zinc Metabolism, C.C. Thomas Publisher, Springfield, H I . , 259 pp.
" (1970) ^blecular Approaches to Plant Physiology, McGraw-Hill Book Co., New York, 398pp.
" and Quigley, J.W. (1966) A method for determining quantitative zinc requirements for growth. S o i l S c i . 1 0 1 , 11-16^
Rana, B.C. and Kumar, H.D. (1974) The t o x i c i t y of zinc to Chlorella vulgaris and Plectonema boryanum and i t s protection by phosphate. Phykos 13, 60-6'5: I
Randhawa, N.S. and Broadbent, F.E. (1965) S o i l organic matter-metal complexes: 5 . Reactions of zinc with model compounds and hiimic acid. S o i l S c i . 99, 295-300.
Reese, M.J. (1957) The microflora of the non-calcareous streams. Eheidol and ffelindwr with s p e c i a l reference to pollution from lead mines i n Cardiganshire. J . Eco l . 25, 385-407.
Sato, M. (1960) Oxidation of sulphide ore bodies. I . Geochemical environments i n terms of Eh and pH, Econ. Geol. 55 , 928-961.
Say, P.J. (1977) Microbial Ecology of High Zinc Level' Streams. Ph.D. Tliesis, Durham University, 295pp-
" Diaz, B.M. and Whitton, B.A. (1977) Influence of zinc on l o t i c plants. I . Tolerance of Hormidium species to zinc. Freshwat. B i o l . 7, 557-376.
" and Whitton, B.A. <1977) Influence of zinc on l o t i c plants. I I . Environmental e f f e c t s on t o x i c i t y of zinc to Hormidium r i v u l a r e . Freshwat. B i o l . 7, 377-584. '
Schnitzer, M. (1971) Metal organic matter interactions i n s o i l s and waters. I n : Faust, S.D, and Hunter, J.V- (eaB)o Organic Compounds i n Aquatic Environments, ^fea?cel Dekker Inc,, New Tork,
- 57 -Shapiro, J. (1964) On the measurement o f f e r r o u s i r o n i n n a t u r a l waters.
Limnol, Oceanogr. 11, 293-298, Sherwood-Taylor, P, (1954) Inorganic and T h e o r e t i c a l Chemistry. Heinemann L t d . ,
Lond., 856 pp. Smith, S, (1923) Lead and zinc ores o f Northumberland and Alston Moor, Spec.
•Rep. Mineral Resources 25, Geol. Surv. of Great B r i t a i n . S t a i n t o n , M.P., Capel, M.J. and Armstrong, F.A.J. (1977) The Chemical Analysis
o f Fresh Water ( 2 e ) . F i s h Mar, Serv. Misc. Publ. 25, Freshwater I n s t i t u t e , Winnipeg, Manitoba, l66pp.
Stokes, P.M. (1973) Heavy metal tolerances i n algae i s o l a t e d from contaminated lakes near Sudbury, Ontario. Can. J. Bot. 5 I , 2155
Stout, P.R. (1961) Proc. 9 th . Annual C a l i f o r n i a F e r t i l i s e r Conference. I n : P r i c e , C.A. (197O) pp 2OI-265. Molecular Approaches t o Plant Physiology. McGraw-Hill Book Co., New York, 398 pp.
Stumm, W. and Morgan, J.J, (I97O) Aquatic Chemistry. An i n t r o d u c t i o n emphasizing Chemical E q u i l i b r i a i n Natural Waters: , Wiley-Interscience, New York, 583pp.
Thornton, I . (1974) Applied geochemistry i n r e l a t i o n t o mining and the environment. I n : Jones, M.J, (ed.) pp.87-101. Minerals and the Environment. I n s t i t u t i o n o f Mining and Metallurgy, Lond., 803pp,
Todd, W,R, Elvehjem, C.A. and Hart, E.B. (1934) Zinc i n the n u t r i t i o n of the r a t . Am J. P h y s i o l . IO7, 146-156,
Tucker, A, (1972I The Toxic Metals, Earth I s l a n d L t d , , Lond,, 237pp. Turner, R.G, (1968) Heavy metal tolerance i n p l a n t s . I n : Rorison, I.H, ( e d ) ,
PP 339-410. E c o l o g i c a l Aspects of the Mineral N u t r i t i o n of Plants. Blackw e l l S c i . Pub., Oxford.
Waksman, S.A, and Foster, J.W. ( I 938 ) R e s p i r a t i o n and l a c t i c a c i d production by a fungus o f the genus Rhizopus, J, A g r i c , Res, 57, 873-899.
Wedepohl, K,H, (1972) Environmental i n f l u e n c e s on the chemical composition o f shales and c l a y s , Phys, Chem. Earth 8 , 3O5-333.
Whitehead, N.E, and Brooks, R,R, (I969) Aquatic bryophytes as i n d i c a t o r s o f uranium m i n e r a l i s a t i o n , B r y o l o g i s t 72, 5Q1-507.
Whitton, B,A, (197O) T o x i c i t y o f z i n c , copper and lead t o Chlorophyta from f l o w i n g waters, A r c h i v , M i k r o b i o l , 72, 353-360,
" and Say, P, J, (1975) Heavy metals. I n : Whitton, B,A, (ed,) pp,286-311, River Ecology. B l a c k w e l l S c i , Pub,, Oxford, 725pp.
W i l k i n s , (1957) A technique f o r the measurement of lead tolerance i n p l a n t s . Nature, Lond. I80, 37.
W i l l i a m s , S.L,, Aulenbach, D,B, and C l e s c e r i , N,L. (1974) Sources and d i s t r i b u t i o n o f t r a c e metals i n aquatic environments. I n : Rubin, A.J. (ed.) pp. 77-127, Aqueous-Environmental Chemistry of Metals. Ann Arbor Science Publishers I n c . Michigan, 390pp.
Zak, P. (1966) Determination o f zinc i n b i o l o g i c a l m a t e r i a l s . I n : Prasad, A.S. (ed.) (1966) pp.3-26, Zinc Metabolism, C,C. Thomas Publisher, S p r i n g f i e l d , H I . , 259pp.
Z i r i n o , A. and Yamamoto, S. (1972) A pH-dependent model f o r the chemical s p e c i a t i o n o f copper, z i n c , cadmium and lead i n sea water. Limnol. Oceanogr. 17, 66I-67I.
- 58 -
SUMMARY
( i ) Data has been collected r e l a t i n g to the accumulation of zinc i n seven species of bryophytes and algae growing submerged i n an upland stream flowing through an area of past and present mining a c t i v i t y .
( i i ) Six sampling sites were established i n the catchment of Rookhope Burn, a t r i b u t a r y of the River Wear.
( i i i ) Levels of Zn, Pb, Cd, Ca, Mg, Fe, NO -N, NH -N and PO -P i n water were determined at 10-1'f day intervals over a 60 day sampling programme. The environmental variables of water measured at each s i t e were pH, temperature, t o t a l a l k a l i n i t y , e l e c t r i c a l conductivity and optical density. Water flow wa^ estimated at each colle c t i o n .
( i v ) Growth, chlorophyll a concentration and zinc content of transplanted shoots of Scapania iindulata (L.) Dum. were determined at sites with d i f f e r i n g levels of zinc i n water.
(v) Zinc and cadmium levels i n water show a positive correlation ( r = 0.95^, p<O.Ol)
( v i ) Levels of zinc i n water show a lin e a r relationship with the zinc content of plant tissues up to 0.5 mg 1 zinc i n 'nuclepore' water samples. Above t h i s l e v e l a plateau i s observed.
Enrichment r a t i o s f o r the seven species sampled are determined and f o r the three species Scapania undulata Hygrohypnum ochraceum and Lemanea f l u v i a t i l i s are found to be r e l a t i v e l y stable up to 0.5 mg 1 zinc i n water.
( v i i ) No evidence i s found from the transplant study f o r the existence of d i f f e r e n t strains of Scapania undulata.
( v i i i ) Accumulation i s b r i e f l y discussed i n r e l a t i o n to the levels of cations and anions determined and i n r e l a t i o n to the environmental measures.
- 59 -APPENDIX A
SITE DESCRIPTIONS IN ROOKHOPE BURN CATCHMENT
SITE 1 SOUTH GRAIN
Stream Number::0219 Reach Number: 75
Site Description: 200m above entry of South Foul Sike.
Grid Ref: NY 877'+ 2 Map Ref: 3h°h7 02° 1o'
Width: 0.5 - 1.3m Depth: 0.1 - 0.5m F a l l : 1m .
Substrate: Sandstone rocks and gravel.
Submerged f l o r a : Scapania undulata growing densely on exposed and submerged rocks
Upstream features: Extensive drainage on upper f e l l s .
SITE 2 ROOKHOPE BURN
Stream Number: 0012 Reach Number: 15
Site Description: 300m above Grove Rake mine.
Grid Ref: NY ?>3khh3 Map Ref: 5^°^?' 02°09'
Width: 1 - 2.5in Depth: 0.10 - 0.25m F a l l : 0.5m
Substrate: Sandstone rocks and gravel-
Submerged f l o r a : Scapania undulata growing densely on exposed and submerged rocks i n rapids. Hygrohypnum ochraceum submerged and emergent on sandstone rocks. Batrachospermum sp, continuously submerged, attached to sandstone rocks.
Upstream features: old lead mine t a i l i n g s .
- 60 -
SITE 3 ROOKHOPE BURN
Stream Number: 0012 Reach Number: 30
Site Description: immediately below road bridge
Grid Ref: NY 92kkj>0 Map Ref: ^k^kS' 02°0G'
Substrate: Sandstone rocks, heavy deposits of sediments.
Submerged f l o r a : Very r e s t r i c t e d growth. Small populations of Scapania undulata and Dichodontium pelltiicidum growing as emergent species except at high flows. Growth of Mougeotia sp. i n shallows at low flows.
Upstream features: Adits from old lead mine workings. Grove Rake mine, Redburn mine.
SITE k ROOKHOPE BURN
Stream Number: 0012 Reach Number: 38
Site Description: Below fluorspar washing plant
Grid Ref: NY 9 +1 23 Map Ref: ^k^hs' 02°05'
Width: 3-5m Depth: 0.25 - O. fOm F a l l : 0.25ra
Substrate: Sandstone rocks with heavy precipitates of iron oxides
Submerged f l o r a : Stigesclonium tenue attached to rocks as a transient species. Hygrohypnum ochraceum as stunted growth on exposed rocks only. Mpugeotia sp. i n shallows at lowest flows.
Upstream features: Fluorspar washing plant.
- 61 -
SITE 5 ROOKHOPE BURJj
Stream Number: 0012 Reach Number: 1
Site Description: Above foot bridge
Grid Ref: NY kkk^6 Map Ref: 3^°'^3' 02°6h'
Width: 3-5m Depth: 0.25 - 0.30m F a l l : 0.15m
Substrate: Limestone blocks, sandstone rocks and gravel.
Submerged f l o r a : Hygrohypnum ochraceum submerged and emergent. Small populations of Hygrohypnum luridum,Fontinalis antipyretica and Hygroamblystegium f l u v i a t i l e
Upstream features: Sewage treatment works.
SITE 6 ROOKHOPE BURN
Stream Number: 0012 Reach Number: k6
Site Description: Eastgate, below road bridge
Grid Ref: NY 953386 Map Ref: 3^°hk' 02°0i/
Width: 5-7ni Depth: 0.25 - O.JOm F a l l : 0.15m
Substrate: Limestone blocks and gravel.
Submerged f l o r a : Dominated by Lemanea f l u v i a t i l i s , continuously submerged, attached to limestone blocks. Populations of Hygrohypnum ochraceum as emergent species.
Upstream features: Caravan park, open drain from Eastgate villeige, farmland. Banks of stream extensively covered by trees giving considerable shade.
62
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- 65
B - 2 Results of Student's ' t ' test of pairs of ' t o t a l ' and 'nuclepore' samples (n = 6)
C t ' test for Pb missing; 'nuclepore'sample 27th June 1978, day hO , not available for analysis)
SA1-5PLE 2^ Cd Ca Mg Fe SITE
I f 2.105 1.3^2 0.^90 0.790 1.56'f
P
P
' t ' P
<0.10 NS NS NS NS
' t ' 0.793 2.121 .0.273 0.077 1.881 NS <^,0.10 NS NS <0.10
0.7if5 1.3^2 0,if63 0.503 1.69 NS NS NS NS NS
' t ' 1.933 1'000 0. +95 0.205 1.133
p <0.10 NS NS NS NS.
' t ' 1.323 1.3^2 . 0.186 0.221 2.200 p NS NS NS NS <0 .10
' t ' 1.162. 0.707 0.272 0.118 1.907 p NS NS NS NS <. 0.10
- 66
APPENDIX C I - VI
Levels of aiiions at 6 sampling sites on 6 sample dates (mg 1~ )
i SaiiTg^le_date_]^A/Z8
Site NO -N NH,-N PO,-P 3 ^ 4
1 0.0ff7 0.150 0.027
2 0.180 0.1 ifO 0.005
3 0.09^ 0.150 0.015
• h O.Hif 0.120 0.011
5 0.201 0.lif5 0.018
6 0.288 O.l'fO 0.032
i i Sample date I /6 /78
1 0.066 0.135 0.012
2 0.030 0.090 0.013
3 0.118 0.097 0.019
h 0.114 0.100 O.OOif 5 0.19'f 0.123 0.010
6 0.115 0.120 0.015
i i i Sample date 15/6/78
1 0.053 0.2h3 0.011
2 0.035 0.165 0.022
3 0.138 0.200 0.019
k O.ioS 0.170 0.010
5 0.276 0.195 0.019 6 0.289 0.180 0.016
.- 67 - •
i v Sample date 2?/6/73
Site NO -N NH -N PO -P
1 0.l8if 0.200 0.023
2 0.393 0.135 0.039
3 0.296 0.166 0.019
k 0.286 0.135 0.011
5 0.166 0.l6if 0.018
6 0.587 O.l^tl 0.019
V Sample date 7/7/78
1 0.163 0.337 0.013
2 O.l^fO 0.164 0.016
3 0.277 0.167 0.015
,h 0e155 0.155 0.014
5 0.299 0.155 0.021
6 0.279 0.150 0.019
v i Sample dabe 17/7/73
1 0.072 0.395 0.006
2 0.029 0.225 0.009
3 0.119 0.245 0.006
4 0.066 0.185 0.005
5 0.377 0.190 0.017
6 0.427 0.170 0.016
- 68 -
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