Effect of air pollution on biodiversity of coastal lichens

Extended EssayResearch Question: What effect has the development of Castle Peak Power

Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ?

Subject: BiologyCandidate Name: Anahita Sharma

Number: 003258-138

Exam Session: May 2012Word Count: 3950

Abstract

This essay examines the impact of the 1981 commissioning of the coastal Castle Peak Power Station on a 1980 established zone of normal lichen growth. The research question is ‘What effect has the development of Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? Site A is a rocky outcrop 200 metres downwind, whereas Site B is 1.6 kilometres upwind, from the power station; Site A is therefore significantly more exposed to by-products produced as a result of the station’s activities. Any impact on coastal lichen growth produced by the station would be suggested by differences between these sites, thirty years later.

Lichens readily absorb pollutants that may damage the algae-fungi symbiosis. The investigation was approached with three indicators of health within the lichen community: population size, type of lichen, and biodiversity. The lichen was classified in the field, the population size determined by percentage covers over randomly selected quadrats, and the biodiversity a combination of the former dependent variables. The scope was limited to coastal species found on granitic rock within the supra-littoral zone (approximately 3.68 m above chart datum) between two independent sites under similar abiotic conditions. Representative results could be achieved by selecting more sites under uniform conditions. The research was also limited by a dearth of historical data with which to compare.

The results supported the hypothesis: there was a greater Simpson’s biodiversity level (4.48 compared to 3.45) and overall percentage cover of species at Site B. At site B, four out of six species common to both sites were found to be more frequently found and at a significantly (at a minimum confidence limit of 95%) higher percentage cover than at Site A. This baseline study indeed prompts further investigation.

Word Count: 299

ii

Contents 1. Introduction• ! 1.1 Hypotheses and Justification................................................................ p. 1• 1.2 Lichen Biology..................................................................................... p. 3• ! 1.3 Coastal Ecology and Site Significance................................................. p. 5

2. Methodology • ! 2.1 Apparatus................................................................................................ p. 8• ! 2.2 Methodology........................................................................................... p. 9• 2.3 Spatial Site Observations........................................................................ p. 10• 2.4 Abiotic Factors........................................................................................ p. 11 3. Treatment• ! 3.1 Presence................................................................................................. p. 12• 3.2 Transformation...................................................................................... p. 12• 3.3 Statistical Significance: Independent samples t-test.............................. p. 14• 3.4 Biodiversity............................................................................................ p. 16• 3.5 Data Presentation................................................................................... p. 17

4. Discussion• 4.1 Conclusion.............................................................................................. p. 18• 4.2 Evaluation and further areas of study..................................................... p. 19

5. Works Cited................................................................................ p. 21

A. Appendix• A1: Raw data........................................................................................................................... p. 22• A2: Photographs of sites.......................................................................................................... p. 25• A3: Quadrat size determination data........................................................................................ p. 26• A4: Lichen species found......................................................................................................... p. 27

iii

Introduction

Research Question: What effect has the development of Castle Peak Power Station had on the percentage cover and

biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ?

1.1 Hypotheses and Justification

Whilst making field observations, I considered whether the environmental impact of Hong Kong’s

largest coal-fired power stations (Castle Peak 1981) and its adjacent industrial establishments could be

biologically assessed.

Because the Castle Peak establishments are directly situated on the coast, coastal

lichens growing in the supra-littoral zone of the rocky shore were used as

‘bioindicators’. Lichens growing on substrate further inland would not have been

representative of the effect of Castle Peak.

Lichens are free and simple mechanisms for assessing the air pollution levels of a

potentially large source. I was interested and passionated about this subject because

air pollution is a relevant, daily point of conflict in Hong Kong. The CLP group

which partly owns the power stations, lists (gaseous) waste by-products of coal as

an energy source (fig. 1.1.1), many of which are known to affect lichens. In

addition, there have been few studies on lichens in Hong Kong; this investigation

builds upon S.L. Thrower’s work in 1979, when Hong Kong was mapped using

indicator lichen genera in terms of pollution zones.

fig. 1.1.1 waste by-products of coal energy source (source: CLP Group)

Lichens have been successfully used in other studies, for example, the works Hawksworth & Rose,

to assess air pollution and other factors. Fig 1.1.2 shows a covariation between lichen biodiversity and lung

cancer mortality. There is a strong case between air pollution and (human or ecological) health, because our

noses are not equipped to filter particles less than 10 micrometers (e.g. non-particulate gases including SO2

which causes both lung irritation in humans and chlorophyll damage in the photosynthetic component of

lichens).

fig. 1.1.2 ! map showing relationship

between lichen biodiversity and health:

lung cancer mortality

(higher the diversity value, lower the

mortality rate) (Purvis 101)

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? 1 Introduction

1Anahita Sharma 003258-138

‘Bioindication’ is the use of an organism to obtain information on the quality of its environment (Purvis

76). Coastal lichens are good bioindicators because of their perennial, cumulative exposure to a moist

environment. Their metabolic rate increases under hydrated conditions, and the aqueous solubility of many

pollutants in means that these lichens can become ‘sinks’ for pollutants (e.g. SO2) even when metabolically

inactive (Nash 299). In addition, “where pollution levels are increasing lichen response is usually rapid, but

when these arez ameliorating... a time-lag does indeed occur.” (Hawksworth and Hill 135). As lichens solely

rely on atmospheric intake, growth is slow, and this means that if retrofitting to reduce emissions was

successful in 2005, the effect of the potentially higher air quality may not be entirely reflected through

present data collection. To rectify this, an idea is gleaned between comparisons of two sites.

From ‘Quantitative Approaches to Air Quality Studies’ (Will-Wolf 109), “species presence and cover

are the most important measures for lichen community data”.

My study followed: “Plan to collect samples both where air pollution is or is expected to be present and

where it is absent but all else is the same... If no historical records are available for the area being studied,

comparisons must be made with nearby comparable areas that are either presumed or known to be free

of air pollution”. The nature of this investigation means that some - fair - assumptions are made; this is

indeed a limitation of bioindication.

This baseline study examines differences between lichen coverage and biodiversity over the scope of

two sites. I hypothesize that species that would have survived would have disappeared from the substrate in

Site A. Site A is a displacement of 0.2 km from the stations, whereas Site B is 1.6 km away. (for Site and

Castle Peak photographs, refer to A1 (Appendix).

The uniformity of the substrate and abiotic conditions justified the choice of the rocky shore sites, which

primarily different in their situation with respects to the power stations.

This formed the hypotheses (height justified in 1.3):H1 (Alternative Hypothesis): Site A has a lower lichen percentage cover at 3.68 ± 0.01 m above chart

datum and/or a lower biodiversity value than Site B.

H0 (Null Hypothesis): There is no significant difference in lichen percentage covers and/or biodiversity of

lichen between the rocky shore sites at 3.68 ± 0.01 m above chart datum.

This study records the percentage cover of all species found, because different species have different

pollution sensitivities. Sensitivity is influenced by ‘tolerance’ or ‘avoidance’. An example of ‘avoidance’ is

‘limited wettability’, which means the lichen decreases its porosity (Hawksworth and Hill 131).

Within lichens, a greater biodiversity suggests ecological health in that several species are able to

compete in the environment. Biodiversity is calculated by combining both the percentage cover and number

of species (species richness). A low biodiversity suggests a dominance of a few, possibly pollution-tolerant

species. The type of lichen (Section 1.2) is very significant, because, in general, “the more the lichen sticks

out from its substrate, the purer the air” (Thrower 5, 1979).



! Variables

fig 1.1.5: table showing variables used to test hypothesis

Dependent The location: rocky shore sites determined by the distance and predominant wind direction from Castle Peak “a” Power Station.Site A: 0.2 km downwind, Site B: 1.6 km upwind ± 0.05 km

The location: rocky shore sites determined by the distance and predominant wind direction from Castle Peak “a” Power Station.Site A: 0.2 km downwind, Site B: 1.6 km upwind ± 0.05 km

Controlled variables Independent Species and percentage cover per quadrat (± standard deviation of species over 60 quadrats)

Controlled variables

Fixed Abiotic conditions such as rock type, shore height, aspect: however, biological variation is appreciated and monitored.

Uncontrolled variables An uncontrolled variable that may have a significant effect on the dependent variable is marine pollution - as lichens are also sensitive to marine effluents - which may affect Site B differently from Site A. This is, if not controlled, monitored.

An uncontrolled variable that may have a significant effect on the dependent variable is marine pollution - as lichens are also sensitive to marine effluents - which may affect Site B differently from Site A. This is, if not controlled, monitored.

1.2 Lichen Biology

A lichen is “an association of a fungus and a photosynthetic symbiont resulting in a stable thallus

(body)” (Hawksworth and Hill 2). The algal complex is the photobiont (autotrophic/photosynthetic partner).

The mycobiont (fungi) has hyphae (cellular threads) adheres to hard, desiccated substrata, protecting the

photobiont against exposure and water loss and liberalizing minerals through the biochemical weathering of

substrate. This is mutualistic: for the mycobiont, lichenization is a form of heterotrophic nutrition; the

photobiont’s access to light increases (Nash 3).

Colonies organise themselves in degrees of increasing complexity: crustose, squamulose (scaly),

foliose (leafy) and fructicose (bushy). An accepted rule of thumb is the more complex the structure, the

greater its sensitivity to atmospheric pollutants. This reinforces the significance of not only the number,

but the type of lichen found at each site i.e. a large number of fructicose or foliose lichens would signify

good air quality.

fig 1.2.1 cross-section of lichen (Thrower 1979)

Crustose lichens (fig 1.1.1) are thin, granular, smooth or powdery crusts.



Algal cells caught in fungal weft (mycelium).

Lower fungal cortex (coat)

fig 1.2.2 diagram of foliose structure (Dobson 26)

Squamulose or foliose lichens (fig 1.2.2) constitute flat ‘lobes’ or layers of tissue. Rhizines, “root-like

threads” (Thrower 1988), anchor the thallus.

fig 1.2.3 cross-section of fructicose lichen (Dobson 26)

Fructicose lichens are thread-like, stalk-like or bushy, with a central cylinder of hyphae (fig 1.2.3).

As lichens contain no vascular system, they have “developed efficient mechanisms for taking up water

and nutrients from atmospheric sources” (Nash 299). Because they lack a cuticle or stomata, aerosols are

absorbed over the thallus and there is little control over gas exchange. Once absorbed, the substance is

metabolised or bioaccumulated - this characteristic is normally advantageous on barren surfaces but in the

presence of polluted air, has become a threat to lichens (Thrower 4, 1988). They cannot regenerate existing

parts. Because lichens are poikilohydric - their “water status varies passively with surrounding

environmental conditions” (Nash 5) - their biomass directly varies with mean annual precipitations.

Recurring dehydration concentrates solutions to toxic levels which diffuse down to the photobiont layer in

the medulla, potentially rupturing the delicate symbiotic balance.

These substances irreversibly damage lichen metabolism via the photobiont as shown through

fumigation studies: “changes in respiration rates, increases in potassium efflux... chlorophyll

degradation” (Fields 175). They may inhibit photosynthetic fixation and the development of fruiting bodies

or spores for germination. The photobiont diverts energy to repair itself; the mycobiont which relies on it as a

source of nutrition is affected. Coastal lichens are additionally susceptible to marine oils, emulsifiers and

detergents.



1.3 Coastal Ecology and Site Significance

Coastal lichens are least affected by Hong Kong’s development and hill-fires and can effectively represent air

quality levels. This study focuses on lichens colonizing granitic outcrops or boulders in Lung Kwu Tan,

where I noticed there was a power station in close proximity to the shore.

fig 1.3.1! subdivisions of rocky shore profile

Rocky shores experience a steep environmental gradient (fig 1.3.1). Species that can “withstand extended

periods out of water” (Williams 2003) are distributed up shore in the splash or supra-littoral zone (Williams

2003). This presents advantages such as decreased interspecific competition and wave action.

After site visits it was notable that the lichens occur in a band higher up shore (approximately 3.00-4.00 m),

whereas the more frequently submerged parts of the shore were covered by cyanobacterial mats and

(seasonal) encrusting or erect algal species. Two fructicose species, Roccella sinensis and Ramalina litoralis,

occur almost exclusively in this habitat (Thrower 1988).

Lung Kwu Tan (Tuen Mun, Hong Kong)

A report by S.L. Thrower on the results of the ‘Clean Air and Lichens’ Project in 1979 that assessed lichen

growth in terms of pollution zones indicates that Lung Kwu Tan fell into a zone of ‘Normal Growth’ for

foliose and fructicose species. Such a categorization suggested a maximum of 50 micrograms per m3 of SO2

concentration; the upper annual average limit for the station is now 80 micrograms per m3 (Castle Peak



Supra-littorallichens

Power Station EPD Air Pollution Assessment). However, mean levels as low as 30 micrograms per m3 have

affected lichen species in the field (Hawksworth & Hill 131).

This baseline study explores whether the commission of the coal-fired Castle Peak Power stations - the

largest in Hong Kong at a gross capacity of 4108 MW (CLP) - and adjacent industrial activities in 1982 - had

any effect on lichen growth after Thrower’s report, by examining the difference in percentage cover and

biodiversity of two shores that are impacted very differently by such a development, but are otherwise

similar in terms of aspect, shore exposure, substrate and

other biotic and abiotic conditions.

fig.1.3.3! map from

‘Report on Clean Air and

Lichens

Fig 1.3.3 marks Thrower’s pollution zones in Hong

Kong in 1979; lichen deserts were associated with the

presence of power stations, industrial areas, or

desalting plants. As lichens grow at an average of

between 0.1 and 1 cm in radius annually (Jennings

132), prolonged exposure to high degrees of both

terrestrial and marine pollution would certainly affect the biodiversity of lichens on the shore, rate of new

growth, and their thallus size (the latter two affecting percentage cover).

fig 1.3.4 map of Sites

GPS Coordinates

Site A: N 22.378791 E 113.917893

Site B: N 22.391284 E 113.918024

The prevailing southern wind direction

indicates that effluents produced by

Castle Peak Power Station will not

directly affect Site B upwind, whereas

they will affect Site A, downwind.

This may not affect lichen growth or biodiversity if levels of of certain pollutants are not beyond a tolerable

limit. ‘Pollution’ encompasses a wide number of variables.

The combustion of fossil fuels results in the additional output of pollutants (fig 1.3.6), ultimately “[racing]

the energy cycles of nature” (fig 1.3.5) (Singer 105).



Lung Kwu Tan :zone of normal growth for fructicose and foliose species in 1979

fig 1.3.5! the energy cycle of a power station

The proximity from the coal-fired power stations is associated

with impact. I hypothesize that this affects lichen abundance and

biodiversity in the supra-littoral zone on rocky shores in Lung

Kwu Tan.

The Power Station Environmental Impact Report rated the

intertidal habit of ‘Low’ ecological importance, of no

conservational interest. Lichens were not featured. The

introduction of low sulfur fuels and retrofits has purportedly

reduced NOx and SO2 emissions by 77% and 44% respectively, but these levels still affect lichen

communities (as aforementioned).

As lichen distribution is not affected on a short-term, daily basis, they can be used to study a long-term

impact. If the CLP initiatives to were effective, the lichen population abundance and diversity on Site B

should not significantly differ from Site A. Either was equally possible.

Word Count: 1580



2! Methodology

2.1 Apparatus

fig 2.1.1 table showing list of equipment neededIf uncertainties are not sourced, they are derived from the greatest unit of precision.

Apparatus/materials Quantity Purpose Uncertainty

Gridded Quadrat (0.5 m by 0.5 m)*

1 To determine the percentage cover of a lichen species within the area of the quadrat.

1 square represents 1% as the square is divided 10 by 10.

Transect line (m) 1 To lay over the representative shore. ± 0.01 m

Magnifying glass 1 Aid lichen identification. -

Lichen books - Aid lichen identification. -

Metre ruler (m) 3 Determine tidal height (from chart datum) with spirit levels and predicted tidal chart.

± 0.001 m

Spirit level 3 To avoid parallax error when measuring height. -

Predicted tide level chart (Hong Kong Observatory)

1 To show tidal height at time of collection and measure specific height

-

GPS-enabled device 1 Site location. Accuracy ± 10 yds

Camera 1 To record appearance of lichen if unidentified. -

Random numbers table 1 To ensure quadrat positions are randomly selected from transect.

-

Ballantine Scale table 1 To ensure sites are of similar wave exposure through this biological (zonation) scale.

-

*QUADRAT SIZE DETERMINATIONA gridded quadrat efficiently enables percentage cover calculation in the field. This size was reinforced by a

quick running means test on percentage cover. From fig 2.1.2, we can see that it is a suitable size as the curve

levels out and a 0.2500 m2 is representative of lichen communities.

fig 2.1.2! determination of quadrat size: graph

For data, refer to A2 (Appendix).

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? 2 Methodology


0

25

50

75

100

0.0025 0.0625 0.2500

Percentage cover (%)

Quadrat Area (m2)

2.2 Methodology

SAMPLINGRandom positions along the transect were selected from a random numbers table. A sample size of sixty

quadrats was representative, as it covered 50% of the zone along the quadrat.

TIDAL HEIGHT DETERMINATIONThe tidal height is determined because, from prior research and site observations, coastal lichens are

distributed over the supra-littoral zone (i.e. at higher shore heights) and are rarely submerged.

fig 2.2.1! diagram showing how tidal height is measured

The spirit levels were

used to put three straight

rulers (fig 2.2.1) to

measure the height

difference from a pre-

determined tide level (fig

2.2.2).

fig 2.2.2! tidal chart (HKO)

ERROR ANALYSIS: The tidal chart

used was a prediction of the tide on the

day, so will have been inaccurate. I do not

think this caused significant error.

SPECIES IDENTIFICATION: To be ecologically sensitive, I visually identified lichens in the field with a

magnifying glass.

ERROR ANALYSIS: This choice to not chemically test lichen may have resulted in misidentification. To

minimize this, I researched the identified species’ habitat.

QUADRAT RULESThe quadrat was pressed against the vertical/horizontal/diagonal rock surface above and below the transect

line, with the bottom-left and top-left corner respectively touching the value on the line.

ERROR ANALYSIS: The substrate may not necessarily be flat where the quadrat is laid, and there may be

parallax error when counting.



fig 2.2.3! sketch of gridded quadrat on lichenous surface

Each square counted as 1% for an individual species. It was possible that

the coverage of species added up to more than 100% when more than one

was present within the same square.

LIMITATION: I rejected the possibility of measuring the thallus size of

each species due to impracticality. The limitation is that it is possible a

large thallus could be more relevant than, say, number of small thalli, and it

may not be fair to collectively consider them under ‘percentage cover’.

ERROR ANALYSIS: The method for percentage cover was not highly precise but provided an accurate

estimate. Sampling sixty quadrats increased the reliability of the data.

METHOD

1. Roughly estimate 3.700 m above chart datum by using the method shown in figures 2.2.1-2.

1. Lay a transect approximately 60.00 metres long.

3. Using the random numbers table, find positions for the 0.5 m by 0.5 m quadrat along the transect. If the

random number does not fall on a position where the quadrat can be laid against a rocky, granite substrate,

then move on to the next random number. If the position yields sampling possibilities on both sides of the

transect line, sample on both sides.

4. Identify any species seen in the quadrat and write it in the ‘Species’ column. Calculate the percentage

cover as shown by the method in fig 2.2.3. Place the quadrat both below and above the transect line.

5. Repeat steps 3-4 with the next position. If new species are identified, add them to the ‘Species’ column

and write in their percentage cover. Species should be subsequently marked as 0% if they are found not to

be present within the quadrat.

6. Repeat this method for 60 quadrats. 50% of the lichen population along the 60.00-metre transect at 3.700

m tidal height will have been sampled, increasing reliability.

2.3 Spatial Site Observations- Site photographs can be found in A2 of the Appendix.

A village lies at the back of the bay whereas directly behind the beach. The

power stations lie to the left of the bay, at an approximately 1.6 kilometre

displacement away from Site B and 0.2 kilometre displacement from Site A. They were seen from both Sites A and B. A white gas, possibly steam, was

seen; at Site A, there was a pungent odour, possibly liquid natural gas.



fig 2.3.1 satellite map

From fig 2.3.2, it is evident that pollutants generated

by the stations affect lichens at Site B to a far lesser

extent when compared to the

lichens at Site A.

From the Environmental

Impact Assessment of the

Emissions Control Project of

Castle Peak Power Station

(2006):

a) Effluents are discharged into coastal waters and the

site receives weekly traffic.

b) Lung Kwu Upper (Site B) is rated as a ‘Fair’ beach

whereas Lung Kwu Lower (Site A) is ‘poor’.

2.4 Abiotic FactorsWhether the rock is a xeric (dry), mesic (moist) or submesic habitat, light intensity, the sheltering of other

rocks and crevices also determine distribution across the tidal height. Whilst it is difficult to isolate Castle

Peak Power Station impact as the sole variable, we can monitor and attempt to control certain variables.

Tidal Height: a supra-littoral height of 3.700 m was found appropriate for lichen growth. Deviation from

this height was a half-metre below and above (quadrat method); Chu (1997) showed that in Hong Kong,

lichen cover and diversity increase with tidal height; the zone is characterized by the genera Blastenia,

Caloplaca, Buellia, Parmotrema, Ramalina and Roccella (all of these found in data collection).

Substrate: granite boulders were present in both sites; numerous species of lichens readily grow on this

substrate.

Shore Exposure: Chu showed that exposure influences the height and vertical width of the supralittoral

zone. Similarity was achieved through the use of the Ballantine Scale, which uses zonation patterns.

Aspect: A bearing of NW 340-350°; the direction the shores face is important in terms of wind and sunlight

exposure. Chu (1997) showed the effect of aspect relates to prevailing winds; lichen diversity and cover is

higher on south- or east-facing shores due to a milder climate.

Water Pollution: Oils, emulsifiers and marine effluents may affect coastal lichens. However, marine data

provided by the EPD for factors in the area seems to suggest that there are no significant variations over the

area (NM5 Zone) as per 2009 data which provides values for factors such as dissolved oxygen, suspended

solids, ammonia, nitrogen, phosphates; this makes Site A and B still comparable.

If the Power Station were to release marine pollutants, the would affect downwind Site A over Site B; the

hypothesis is still supported. Water samples were not taken as both sites occupied the same bay, in which

variations would almost certainly be affected by time rather than location; marine data was available.

Word Count: 960Raw, including qualitative, data and lichen species found are in the Appendix (A1 and A4 respectively).



Lung Kwu Tan(it can be seen that the arrows are pointing in a south-westerly direction, at Tuen Mun and Sha Chau, and South East at the Wetland Park)

fig 2.3.2 map with prevailing wind direction

3 TreatmentThe raw data (quantitative and qualitative) are found in Section A1, and the species list in A4 of the Appendix.

3.1 PresenceThis compares what species are present at both Site A and B, leading into the statistical significance test. The percentage of quadrats each species is found in at Site A or B is expressed in brackets, to aid comparison.

Worked example: % of quadrats D. actinostomus is found in at Site A

fig 3.1.1 table showing species present at Site A and B

Species Site A Site B

B. handelii Present (8.3%) Not present (0.0%)

B. cif. subdisciformis Present (50.0%) Present (23.3%)

C. cinnabarina Present (20.0%) Present (58.3%)

D. actinostomus Present (26.7%) Present (83.3%)

D. picta Not present (0.0%) Present (1.7%)

P. incratassum Present (10.0%) Present (53.3%)

P. cocoes Present (8.3%) Present (13.3%)

R. litoralis Present (8.3%) Not present (0.0%)

R. sinensis Present (5.0%) Not present (0.0%)

Verrucaria Present (43.3%) Present (65.0%)

The species present at both sites are in bold.

3.2 TransformationPercentage cover is a nominal variable, because it represents the nominal, dual variable of ‘presence’ and ‘non-presence’ within a quadrat, not a measurement variable, which could, for example, be the thallus diameter. Nominal variables are summarized as proportions or percentages; the latter is the case here. My data, therefore, do not conform to a normal distribution. They must be transformed before the t-test which assumes a normal distribution. I have chosen to use an Arc Sine transformation, which is used with percentage data obtained from a count; percentage data has imposed limits (0 to 100). My data also conform to its conditions: the values lie, heterogeneously, close to both limits. The arcsin transformation compresses data toward a centre.

Formula and Worked example:

! ! ! where x is the percentage cover; if x = 7:

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? 3 Treatment


I will convert this value (in degrees) to radians to compress all the values to one end of the range (0):

fig 3.2.1: Processed data table showing lichen species common to both Site A and B percentage covers transformed to arcsin values (in radians) in all 60 quadrats

Species / Type

Site Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)Percentage cover after arcsin transformation (radians / 2 s.f.)

Diploschistes actinostomus

Crustose

Site A0.41 0.0 0.10 0.0 0.40 0.0 0.0 0.35 0.0 0.0 0.0 0.0 0.0 0.0 0.45 0.0 0.23 0.0 0.0 0.0


Crustose

Site A 0.0 0.40 0.49 0.27 0.20 0.0 0.34 0.0 0.20 0.0 0.0 0.0 0.00.0

0.0 0.0 0.0 0.0 0.0 0.0 0.0Diploschistes actinostomus

Crustose

Site A0.31 0.0 0.0 0.0 0.0 0.0 0.27 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.20 0.0 0.0 0.34 0.0 0.0


Crustose Site B0.0 0.0 0.0 0.20 0.0 0.290.32 0.0 0.340.800.450.50 0.0 0.290.290.44 0.0 0.250.400.17


Crustose Site B 0.94 0.35 0.45 0.610.290.320.49 0.0 0.440.670.340.290.410.350.611.140.340.270.200.20


Crustose Site B0.73 0.62 0.31 0.0 0.410.320.230.710.600.170.140.200.430.510.140.310.41 0.0 0.400.25

Parmotrema incratassum

Foliose

Site A0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0


Foliose

Site A 0.0 0.20 0.0 0.20 0.14 0.0 0.10 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0Parmotrema incratassum

Foliose

Site A0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.32 0.10 0.0 0.0 0.0 0.0 0.0


Foliose Site B0.0 0.14 1.6 0.0 0.0 0.0 0.0 0.230.20 0.0 0.0 0.0 0.0 0.0 0.430.72 0.0 0.350.80 1.1


Foliose Site B 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.560.380.170.170.170.27 0.0 0.0 0.65 1.6


Foliose Site B0.14 0.35 0.31 0.0 0.14 0.0 0.0 0.0 0.0 0.250.320.450.140.490.440.600.730.670.730.66

Verrucaria

Crustose

Site A0.79 0.57 0.49 0.41 1.25 0.0 0.48 0.0 0.0 0.0 0.0 0.17 0.10 0.0 0.0 0.0 0.0 0.0 0.37 0.0

Verrucaria

Crustose

Site A 0.27 0.0 0.0 0.51 0.0 0.0 0.46 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.25 0.0 0.0 0.50Verrucaria

Crustose

Site A0.61 1.6 0.0 0.34 0.46 0.49 0.00.

00.37 0.45 0.49 0.0 0.32 0.14 0.37 0.0 0.35 0.0 0.0 0.0 0.0

Verrucaria

CrustoseSite B

0.0 0.37 0.0 0.0 0.320.59 0.0 0.0 0.0 0.0 0.0 0.44 0.0 0.410.730.520.480.550.460.92

Verrucaria

CrustoseSite B 0.41 0.29 0.25 0.32 0.0 0.0 0.0 0.0 0.0 0.0 0.640.29 1.1 0.27 0.0 0.40 0.0 0.230.350.67

Verrucaria

CrustoseSite B

0.69 0.73 0 0.570.690.270.27 0.0 0.0 0.490.560.580.490.450.650.37 0.0 0.630.660.50

Caloplacacinnabarina

Crustose

Site A0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0


Crustose

Site A 0.65 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0Caloplacacinnabarina

Crustose

Site A0.0 0.0 0.0 0.0 0.0 0.56 0.91 0.65 0.71 0.20 0.27 0.34 0.0 0.51 0.25 0.34 0.20 0.0 0.0 0.0


CrustoseSite B

0.31 0.0 0.10 0.0 0.10 0.0 0.14 0.0 0.380.460.340.550.290.140.17 0.0 0.290.440.450.62


CrustoseSite B 0.0 0.27 0.27 0.250.710.500.460.71 0.0 0.0 0.0 0.320.140.46 0.0 0.0 0.0 0.0 0.270.10


CrustoseSite B

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.10 0.0 0.0 0.0 0.170.200.140.350.29 0.0 0.0 0.310.10

Pyxine cocoes

Foliose

Site A0.0 0.0 0.10 0.0 0.0 0.0 0.25 0.17 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Pyxine cocoes

Foliose

Site A 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.45 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0Pyxine cocoes

Foliose

Site A0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Pyxine cocoes

Foliose Site B0.23 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Pyxine cocoes

Foliose Site B 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.140.340.170.140.820.140.17 0.0 0.0 0.0 0.0

Pyxine cocoes

Foliose Site B0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Buellia cif. subdisciformis

Crustose

Site A0.49 0.69 0.34 0.44 0.32 0.79 0.64 0.25 0.14 0.58 0.31 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0


Crustose

Site A 1.5 0.92 0.66 1.3 1.6 1.4 1.3 0.10 0.61 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0Buellia cif. subdisciformis

Crustose

Site A0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.37 0.69 0.73 0.20 0.20 0.10 0.23 0.20 0.20 0.27 0.0 0.0 0.0


Crustose Site B0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.31 0.0 0.290.31 0.0 0.200.17 0.0


Crustose Site B 0.14 0.89 0.0 0.0 0.100.46 0.0 0.0 0.77 0.0 0.0 0.0 0.0 0.59 0.0 0.0 0.20 0.0 0.0 0.0


Crustose Site B0.0 0.0 0.0 0.80 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.45 0.0



3.3 Statistical significance: Independent Samples t-test

For species that were found in both Site A and B, a Student’s unpaired t-test is carried out to determine

whether the differences between the mean percentage cover of each population are statistically significant.

This test calculates a critical value (t) that is then compared to a ‘critical value’. If t is below the critical

value, there is no significant difference and the null hypothesis is supported. A t-test was used instead of the

Mann Whitney U test (which may also have been used) in the view that it is more rigorous.

The formula for the t-value is:

This test can only be carried out to compare a species that is present in both Site A and B.

Worked example: D. actinostomus at both Site A and B

1) Calculate the mean percentage cover of the species for each site.

The formula for the mean is:

Where is the mean, is the sum of the percentage covers, and the no. of samples (60).

This is the mean percentage cover. This is the value after transformations, but transforming it back it not

necessary. We are interested in only the final t value after inputting the transformed data.



2) Calculate the standard deviation (s) of the percentage cover of the species for each site.

68% of the data falls within ±1 standard deviation of the mean; it represents the spread of the majority of the

data about the mean. The formula is:

The numerator is the sum of the difference of every value from the mean; this is squared to make it positive

and then divided by the (approximate) number of samples to get the average difference from the mean. It is

then square rooted to cancel out the former function.

The standard deviation is relatively large in comparison with the mean; this wide variation in the percentage

cover of a species over a transect is to be expected because of environmental discrepancies within a uniform

environment.

3) Substitute the above calculations into the formula for the t-value.

fig 3.3.1 table showing t-values and means for species at both Site A and B

Species Site A: Mean Site B: Mean t

B. cif. subdisciformis 0.2928 0.0947 3.2

C. cinnabarina 0.0932 0.1817 2.3

D. actinostomus 0.1475 0.2426 7.0

P. incratassum 0.0177 0.2660 5.1

P. cocoes 0.0162 0.0358 1.1

Verrucaria 0.2067 0.3268 2.2

The site with the higher mean is in red, and the lower in blue, for this is relevant. The means presented are

still in their transformed states.



The critical values (at 2 degrees of freedom) are 1.3 at a 90% confidence limit, 1.7 at 95%, 2.0 at 97.5%,

2.4 at 99%, 2.7 at 99.5%, 3.2 at 99.9% (“Upper Critical Values of the Student’s t-distribution”). The

confidence limit is the probability that the result is not due to ‘chance’ because the probability of exceeding

the critical value is low.

Therefore,

The population of B. cif. subdisciformis is greater at Site A than B at a confidence level of about 99.9%.

The population of C. cinnabarina is greater at Site B than A at a confidence level of 97.5-99%.

The population of D. actinostomus is significantly greater at Site B than A at a confidence level of over

99.9%.

The population of P. incratassum is greater at Site B than A at a confidence level of over 99.9%.

The population difference of P. cocoes is not statistically significant.

The population of Verrucaria is greater at Site B than A at a confidence level of 97.5-99%.

3.4 Biodiversity

The Simpson’s Biodiversity Index (D) is not entirely based on species richness - the number of different

organisms present - but also the proportion of each species in the area.

The formula is as follows:

Where N is the gross number of individuals and n the no. individuals within a species.

In order to represent the biodiversity of an entire site, I will add up all the percentage cover values of a

species. 1% represents 1 individual in this sense, in order to help our calculations. The absolute values do not

matter here, only the values of Site A and B in relation to each other.

Worked example:

Site B is shown to have a higher biodiversity value than Site A.



3.5 Data Presentation

fig 3.5.1 bar graph showing average percentage covers of lichen species common to Site A and B

(± standard deviation)

The error bars extended into the negative portion of the y-axis, but since the percentage cover cannot be a

negative value, this has been omitted. They were derived from the standard deviation; this showed how

lichen species greatly varied in their distribution over the transect. The bar chart shows that for five species

out of six, Site B has a greater mean percentage cover.



4 Discussion

H1: Site A has a lower lichen percentage cover at 3.68 ± 0.01 m above chart datum and/or a lower

biodiversity value than Site B.

4.1! Conclusion

As this is firmly a baseline study, I cannot make causative conclusions from the results.

However, the results show value in further investigation. The quantitative data show that four out of

species common to both sides were statistically and significantly found more frequently and at

higher percentage covers at Site B. B. cif. subdisciformis is the exception.

Although Site A had a higher species richness at 9 different species to Site B’s 7 species, Site B

had a higher (Simpson’s) biodiversity value. This is attributed to the difference in percentage

covers: in 5 out of 9 species at Site A, 10.0% or less of the sampled quadrats contained the species.

In terms of form, the only fructicose (bushy) species - R. sinensis and R. litoralis were found at Site

A - but both of these were found in only 8.3% (5 out of 60) and 5.0% (3 out of 60) quadrats

respectively. They were dry and appeared discoloured as specimens, but their structure was

maintained well enough on the rocky substrate to permit identification. Foliose species were found

at both sites, which indicated, at least, a moderate air quality in general over both sites.

Thrower (1979) established indicator genera, which she categorized into Zones 1-6, 1 being most

polluted and 6 least. No lichens found fell into Zone 6. In Site A, a small sample of Ramalina,

which is in Zone 5, was found, but not to a significant extent. Pyxine, a Zone 2 lichen (most tolerant

of SO2) was found in both Sites A and B, but rarely or occasionally respectively. Parmotrema

indicates Zone 5; at Site B, it was in 53.3% of quadrats whilst only 10.0% at Site A; this is a clear

distinction. Dirinaria, a Zone 4 lichen, is not present at Site A and was only found in one quadrat at

Site B. The alga Protococcus which indicates Zone 1 (a lichen desert) was not found. Data were

unavailable for the other lichens. On the whole, the significantly greater population density of

lichens at Site B signifies a potential relationship (although abiotic differences are still a limitation).

Another factor to be considered is the lag time between the point of contact with the pollution and

when this affects the structure of the lichen.Castle Peak Power Station’s environmental performance has improved:

- July, 1993: EPD suspects Castle Peak Power Station is partially to blame for spikes in sulphur dioxide and

nitrogen oxide levels, which are linked to respiratory disease and “reduced lung functions”. (Finlay SCMP)

- January, 1997: In 1996, all conventional burners were fit with low NOx burners to reduce NOx emissions by

50%. (Watkins SCMP)

- November, 1998: Coal imports are reduced. CLP is trying to buy coal with minimum sulphur content.

(Tang SCMP)

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? 4 Discussion


- November, 2003: Greenpeace claims power generation is responsible for 64% of Hong Kong’s CO2

emissions; CLP Power supplies 80% of power. CLP claims that ‘fuel diversification’ has reduced CO2

emissions by 25% and levels of sulphur dioxide and NOx by 80%. (Gentle SCMP)

- March, 2011: Hong Kong is on the path to reaching or surpassing air pollution-cutting targets because of

retrofitting Castle Peak Power Station with emission control devices. (Cheung SCMP)

It is possible, therefore, that lichen growth may have regenerated or improved with performance.

The qualitative data show that many species were found together, perhaps because they coexist within the same niche. They will of course, affect each other’s percentage covers, because

they indirectly compete for the ideal substrate.The qualitative data also showed few observable differences between Site A and B: both

consisted of large, granitic outcrops, the same type of sand, were exposed to the same exposure and seawater, the only difference being their locations at opposite ends of a large bay. Their suitability

for comparison was reinstated during data collection.Looking at Thrower’s results on air and lichens in 1979, Lung Kwu Tan fell under Pollution

zone number 6: Bushy lichens such as Usnea appear, which has an approximate SO2 concentration of < 35 micrograms/m3.

My results for Site A, however, fall under Zone number 4 where the scaly crusts prevail and Zone 5 for Site B where the leafy lichens begin to appear. This suggests that the introduction of a

pollution source had an effect on the type of growth.Ultimately, Site A and B certainly showed significant differences in lichen abundance, which

supported the initial hypothesis and the value of further study to ascertain these differences, for they cannot be isolated to the Power Station (although it presents a strong case). In future, it would

be necessary to quantitative differences between the sites in terms of pollutants rather than base the study on a locational assumption.

4.2! Evaluation and extensionsThere was certainly great variability in the percentage cover of a species over the transect as

indicated by the relatively very high standard deviations around every mean percentage cover. This can only be explained by the changes in abiotic conditions: whilst the supra-littoral lichens share the

same band and generally homogeneous, terrestrial conditions, each species will have its own realized niche within the potentiality of conditions along the transect. The transect was a straight

displacement across the shore and therefore across rocks that were exposed to slightly different conditions: some were closer to shore, some were further away. To improve this, the transect could

be laid across a series of conditions that are perceivably uniform. As the quadrat positioning was



randomized, I wonder if it would be more useful to use a belt transect along which one could

accurately track any variability in conditions.

One factor that was not directly measured was the individual thallus size. Thalli in crutose

lichens up to 25 cm across are approximately 500 years old (Thrower 1997). This was associated

with percentage cover but in many cases smaller thalli over an area generated similar percentages to

larger thalli over the same area. The age of the lichen is also relevant.

However, the results are replicable because of a standardized method. There were a few

systematic issues: the laying of the quadrat against the rock was occasionally on an uneven surface

and the counting was therefore affected by parallax error. At some random numbers, there was no

rock. Part of my method was the condition of there being the substrate before a measurement could

be taken, and although this cannot be truly changed, it introduces a selective bias. When the quadrat

fell upon a rocky surface containing a crevice, any lichens growing within the crevice could not be

counted. The figures may therefore not be an accurate representation of lichen population, though

one could argue that lichens growing within sheltered zones do not reflect the impact of pollution.

One great shortcoming of this study is the fact that sample size only consisted of two sites.

Comparing more than two sites over an even greater range of pollution would be preferable.

Possibilities for future studies could also include the biomonitoring of lichen growth over a larger

period of time: the use of photographic evidence has been shown to yield results. However, in

general, it is difficult to generalise given an inability to truly control living organisms and varying

environmental conditions.

There were also limitations to the sources of information: Thrower’s 1979 report was based

on a survey carried out by groups of high school students, and therefore the data is not necessarily

standardized nor accurate, nor was there specific information on species’ sensitivity. This research

makes presumptions on the relationship between lichens and pollution and relies on much

secondary data that may not definitely hold true in this context, although there is much evidence to

support that it does. The arbitrary scale constructed to categorize lichens into ‘Rare’, ‘Occasional’,

etc. categories introduced a bias. The lack of similar historical data against which I can compare

against is another shortcoming.

In conclusion, however, the hypothesis (H1) was supported by the data yielded by this

method, and there was certainly a significant difference between the communities two sites likely

affected by the industrial site, although it has improved its environmental performance in recent

years.

Word Count: 1345



AcknowledgmentsI would like to give due thanks to my Dad, who drove me out far and spent many long days in the humid and heat of

Hong Kong helping me collect the data. Only he would do that for me. And my supervisor, Mr Ferguson, as well as the librarians Mrs Ow and Ms Wong.

Works Cited"1.3.6.7.2. Upper Critical Values of the Student's-t Distribution." Web. 28 Aug. 2011. <http://itl.nist.gov/div898/handbook/eda/section3/eda3672.htm>.

Bennett, Donald Peter., and David A. Humphries. Introduction to Field Biology. London: Edward Arnold, 1974. Print."Biodiversity Measures Explained." Raytheon Wildlife Habitat Committee - Wildlife Management. Web. 28 Aug. 2011. <http://rewhc.org/biomeasures.shtml>.

Cadogan, Alan, and Gerry Best. Environment & Ecology. Glasgow: Nelson Blackie, 1993. Print.

Chapman, J. L., and Michael J. Reiss. Ecology: Principles and Applications. Cambridge: Cambridge UP, 1992. Print.

"CLP Hong Kong - Castle Peak Power Station." CLP Power Hong Kong - Powering Hong Kong Responsibly. 2010. Web. 24 Aug. 2011. <https://www.clp.com.hk/ouroperations/power/castlepeakpowerstation/Pages/castlepeakpowerstation.aspx>.

Dobson, Frank S. Lichens: an Illustrated Guide to the British and Irish Species. Slough: Richmond, 2005. Print.Ellis, Christopher J. "Scotland's Lichen Diversity." Diss. Royal Botanic Garden Edinburgh, 2006. Web. 24 Aug. 2011. <http://rbg-web2.rbge.org.uk/lichen/scottish%20lichen%20biodiversity/scotland's%20lichens.pdf>.

Environmental Protection Department. "Emissions Control Project at Castle Peak Power Station “B” Units ENVIRONMENTAL IMPACT ASSESSMENT." EPD Environmental Impact Assessment. Government of Hong Kong, 2006. Web. 2 Oct. 2011. <http://www.epd.gov.hk/eia/register/report/eiareport/eia_1232006/HTML/Main/Contents.htm>.

"European Guideline for Mapping Lichen Diversity as an Indicator of Environmental Stress." Web. <www.thebls.org.uk/content/documents/eumap.pdf>.

Fung, Joanna Chu. Ecology of Supralittoral Lichens on Hong Kong Rocky Shores. Hong Kong: Hong Kong UP, 1997. Print.

Hawksworth, D. L., and David J. Hill. "1.2: Definining Lichen, 1.9: Air Pollution." The Lichen-forming Fungi. Glasgow: Blackie, 1984. Print.Hawksworth, D. L., and Francis Rose. Lichens as Pollution Monitors. London: Edward Arnold, 1976. Print.

"Human Energy Production as a Process in the Biosphere by S. Fred Singer." The Biosphere. San Francisco: W. H. Freeman, 1970. Print.

Jennings, Terry J. Collecting from Nature. Exeter: Wheaton, 1971. Print.

Lepp, Heino. "Pollution and Lichens." Australian National Botanic Gardens - Botanical Web Portal. 7 Mar. 2011. Web. 24 Aug. 2011. <http://www.anbg.gov.au/lichen/ecology-polution.html>.

Marine Department. "EPD Marine Report 2009 (English Version)." EPD. The Government of Hong Kong, 2009. Web. 2 Oct. 2011. <http://www.epd.gov.hk/epd/english/environmentinhk/water/marine_quality/files/Marinereport2009Engv1.pdf>.

Nash, Thomas H., and Volkmar Wirth. "Physiological Responses of Lichens to Air Pollution Fumigations (Rebecca F. Fields)." Lichens, Bryophytes, and Air Quality. Berlin: J. Cramer, 1988. Print.Nash, Thomas H. Lichen Biology. Cambridge: Cambridge UP, 1996. Print.

Purvis, William. Lichens. Washington, DC: Smithsonian Institution, 2000. Print.

Sprent, Janet I. The Ecology of the Nitrogen Cycle. Cambridge [Cambridgeshire: Cambridge UP, 1987. 71. Print.

Thrower, S. L. Clean Air and Lichen Project. Hong Kong: Hong Kong UP, 1979. Print.Thrower, S. L. Hong Kong Lichens. Hong Kong: Urban Council, 1988. Print.

Williams, Gray A., and Kevin J. Caley. Rocky Shores. Hong Kong: Department of Ecology & Biodiversity, The University of Hong Kong, 2003. Print.

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ?


http://itl.nist.gov/div898/handbook/eda/section3/eda3672.htm




http://rewhc.org/biomeasures.shtml




https://www.clp.com.hk/ouroperations/power/castlepeakpowerstation/Pages/castlepeakpowerstation.aspx

https://www.clp.com.hk/ouroperations/power/castlepeakpowerstation/Pages/castlepeakpowerstation.aspx

http://rbg-web2.rbge.org.uk/lichen/scottish%20lichen%20biodiversity/scotland's%20lichens.pdf

http://rbg-web2.rbge.org.uk/lichen/scottish%20lichen%20biodiversity/scotland's%20lichens.pdf

http://www.epd.gov.hk/eia/register/report/eiareport/eia_1232006/HTML/Main/Contents.htm




http://www.thebls.org.uk/content/documents/eumap.pdf




http://www.anbg.gov.au/lichen/ecology-polution.html

http://www.anbg.gov.au/lichen/ecology-polution.html

http://www.epd.gov.hk/epd/english/environmentinhk/water/marine_quality/files/Marinereport2009Engv1.pdf

http://www.epd.gov.hk/epd/english/environmentinhk/water/marine_quality/files/Marinereport2009Engv1.pdf

A1 Raw DataFor lichen identification sheet, refer to A4 (Appendix).

3.1 Quantitative Data

fig 3.1.1: Raw data table showing lichen species percentage cover at SITE ASpecies / Type Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Percentage cover (± 1%)Diploschistes actinostomus

Crustose

16 0 1 0 23 0 0 12 0 0 0 0 0 0 19 0 5 0 0 0Diploschistes actinostomus

Crustose0 15 22 7 4 0 11 0 4 0 0 0 0 0 0 0 0 0 0 0


Crustose 9 0 0 0 0 0 7 0 0 0 0 0 0 0 4 0 0 11 0 0Parmotrema incratassum

Foliose

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Parmotrema incratassum

Foliose0 4 0 4 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0


Foliose 0 0 0 0 0 0 0 0 0 0 0 0 0 10 1 0 0 0 0 0Caloplaca

cinnabarinaCrustose

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Caloplaca cinnabarina

Crustose37 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Caloplaca cinnabarina

Crustose 0 0 0 0 0 28 62 37 42 4 7 11 0 24 6 11 4 0 0 0Pyxine cocoes

Foliose0 0 1 0 0 0 6 3 0 0 0 0 0 0 0 0 0 0 0 0Pyxine cocoes

Foliose 0 0 0 0 0 0 0 0 0 19 0 0 0 0 0 0 0 0 0 0Pyxine cocoes

Foliose0 0 0 0 0 0 0 0 0 0 0 0 0 9 0 0 0 0 0 0

VerrucariaCrustose

50 29 22 16 90 0 21 0 0 0 0 3 1 0 0 0 0 0 13 0VerrucariaCrustose 7 0 0 24 0 0 20 0 0 0 0 0 0 0 0 0 6 0 0 23

VerrucariaCrustose

33 100 0 11 20 22 0 13 19 22 0 10 2 13 0 12 0 0 0 0Buellia cif.

subdisciformisCrustose

22 41 11 18 10 50 36 6 2 30 9 0 0 0 0 0 0 0 0 0Buellia cif. subdisciformis

Crustose99 63 38 95 100 98 90 1 33 0 0 0 0 0 0 0 0 0 0 0


Crustose 0 0 0 0 0 0 0 13 41 45 4 4 1 5 4 4 7 0 0 0Blastenia handelii

Crustose0 0 0 0 0 4 3 0 0 0 0 0 0 0 0 0 0 0 0 0Blastenia handelii

Crustose 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Blastenia handelii

Crustose0 0 0 0 0 0 0 2 2 0 0 0 0 0 0 82 0 0 0 0

Roccella sinensisFructicose

0 0 0 0 0 28 3 16 0 0 0 0 0 0 0 0 0 0 0 0Roccella sinensisFructicose 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Roccella sinensisFructicose

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Ramalina litoralis

Fructicose0 0 0 0 0 0 0 0 0 0 0 0 9 8 0 0 0 0 0 0Ramalina litoralis

Fructicose 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Ramalina litoralis

Fructicose0 0 0 0 0 0 2 2 1 0 0 0 0 0 0 0 0 0 0 0

fig 3.1.2: Raw data table showing lichen species percentage cover at SITE BSpecies Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)Percentage cover (±1 %)


Crustose

0 0 0 4 0 8 10 0 11 48 19 23 0 8 8 18 0 6 15 3Diploschistes actinostomus

Crustose65 12 19 33 8 10 22 0 18 39 11 8 16 12 33 83 11 7 4 4


Crustose 45 34 9 0 16 10 5 42 32 3 2 4 17 24 2 9 16 0 15 6Parmotrema incratassum

Foliose

0 2 100 0 0 0 0 5 4 0 0 0 0 0 17 43 0 12 52 75Parmotrema incratassum

Foliose0 0 0 0 0 0 0 0 0 0 28 14 3 3 3 7 0 0 37 100


Foliose 2 12 9 0 2 0 0 0 0 6 10 19 2 22 18 32 44 39 44 38Caloplaca

cinnabarinaCrustose

9 0 1 0 1 0 2 0 14 20 11 27 8 2 3 0 8 18 19 34Caloplaca cinnabarina

Crustose0 7 7 6 42 23 20 42 0 0 0 10 2 20 0 0 0 0 7 1

Caloplaca cinnabarina

Crustose 0 0 0 0 0 0 0 1 0 0 0 3 4 2 12 8 0 0 9 1Pyxine cocoes

Foliose5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Pyxine cocoes

Foliose 0 0 0 0 0 0 0 0 0 2 11 3 2 53 2 3 0 0 0 0Pyxine cocoes

Foliose0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

VerrucariaCrustose

0 13 0 0 10 31 0 0 0 0 0 18 0 16 44 25 21 27 20 63VerrucariaCrustose 16 8 6 10 0 0 0 0 0 0 36 8 78 7 0 15 0 5 12 39

VerrucariaCrustose

41 44 0 29 41 7 7 0 0 22 28 30 22 19 37 13 0 35 38 23Buellia cif.

subdisciformisCrustose

0 0 0 0 0 0 0 0 0 0 0 0 9 0 8 9 0 4 3 0Buellia cif. subdisciformis

Crustose2 60 0 0 1 20 0 0 49 0 0 0 0 31 0 0 4 0 0 0


Crustose 0 0 0 51 0 0 0 0 0 0 0 0 0 0 0 0 0 0 19 0Dirinaria picta

Squalumose0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0Dirinaria picta

Squalumose 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0Dirinaria picta

Squalumose0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

What effect has the development Castle Peak Power Station had on the percentage cover and biodiversity of coastal lichens in Lung Kwu Tan, Hong Kong ? A Appendix


3.2 Qualitative Data

fig 3.2.1! Table showing qualitative data for Site A

GPS Coordinates N 22.37891 E 113.917893

General aspect of shore NW 350°

Changes over transect At one particular height, deep crevices and shaded areas as well as exposed and sunny areas are covered.

Observed water traffic of time Occasional boats, freighters

Water appearance Grey-green colour

Ballantine scale rating 5 - Fairly shelteredVery little wave action, appears to be directed away from sea, island across breaks fetch

Geographical features Trees are densely growing directly behind Site.Nearest beach is of white-yellow sand, but sand colour turns black and soft at Site A (like at Site B)Trees are behind the rocks.No wind was felt at the time - seemed very sheltered as bay curves in and protects side.

Urban features The Power Station is very close to the Site, which must be accessed through a road leading to the station.A lot of fisherman’s debris and litter lies by the water’s edge and within the rocks.

Substrate features Very large, granite coastal boulders

Other Fructicose lichens are dry / discoloured although still identifiableLichens tend to grow with each other in specific niches, as is the case at Site B.



fig 3.2.2! Table showing qualitative data for Site B

GPS Coordinates N 22.391284 E 113.918024

General aspect of shore NW 340°

Changes over transect Deep crevices are seen; often rock occurs on both sides of transect. Sometimes a lot of sea snails seen on rock / crabs and other motile organisms; sometimes rock is entirely bare.

Observed water traffic of time Small, mainland freighters

Water appearance Grey-green

Ballantine scale rating 5 - Fairly shelteredWeak swash; island across breaks fetch

Geographical features Sand is black and very soft

Urban features About 300 m away from a restaurant, and a basketball court, and 600 m away from residencies. 1600 m away from power station. A dolphin lookout is on the hillside behind the coastal cliff, but is not linked to site in any apparent way.There is much litter (broken bottles, plastics) dumped behind the rocks.

Substrate features Large, granite coastal boulders of same texture and appearance in Site A

Other Lichens tend to grow with each other in specific niches, as is the case at Site A.



Appendix

A2. Photographs of Sites

Site A ! ! ! ! ! ! ! View of power station! ! ! ! ! ! ! from Site A

Site B

Power stations and adjacent facilities (EPD Report)

Type to enter text



A3. Data Recorded for Quadrat Size Determination (using Gridded Quadrat)1 square in 0.5 m by 0.5 m grid = 0.052 = 0.0025 m2 % cover = 0.25(no. of squares) / Area

Area No. of squares containing lichen Percentage cover (%) (2 s.f.)0.0025 1 100

0.0100 3 75

0.0225 4 44

0.0400 7 44

0.0625 11 44

0.0900 15 42

0.1225 21 43

0.1600 30 47

0.2025 39 48

0.25 46 46



A4. Lichen Species found (Thrower 1988)

Blastenia handelii: (left) crustose; whitish-grey irregular patches 4 cm across; thin black margin (hypothallus).

Buellia cif. subdisciformis: (right) crustose; irregular but smooth grey patches 5 cm across with

black hypothallus; dark-grey spots seen in areoles (round, ‘cracked’ divisions) of thallus.

Caloplaca cinnabarina: (below) crustose; a deep orange makes this easily identified; clear areoles; mainly small samples found (2-4 cm across).

Diploschistes actinostomus: crustose; clear, grey colour spreading to large sizes over rock (10 cm+ across); areoles; asocarps are visible as round black spots sunk into the thallus.

Dirinaria picta: squalumose (scaly); pale grey-green circular

patches with raised bumps; resistant to moderate levels of pollution.

Parmotrema incratassum: (right) foliose (leafy); spreads out in circular green-grey ‘lobes’; distinguishable; approximately 30 cm; central part dead and recolonised by young thalli.

Pyxine cocoes: foliose; pale green-grey thallus; overlapping lobes; known to be pollution resistant; confusable with D. picta.

Ramalina litoralis: fructicose (bushy); yellowish-grey, dry samples found; tangled tufts; easily identifiable as one of two coastal, fructicose species.

Roccella sinensis: fructicose; tufted with grey branches to make it easily identifiable.

R. litoralis and R. sinensis are unique to the coastal habitat.

Verrucaria: crustose; black, ‘tar’ lichen; appears to be dark green when dry; common where periodically under water but found at Site A and B in the splash zone; found as circular spots that merge.

All of the above species are generally found on coastal rock. Most were in proximity to each other and on land-facing rock; certain species were more frequently in shaded or sheltered areas whereas others were more light-demanding.



Effect of air pollution on biodiversity of coastal lichens

Science