Study on the goal of ecological rehabilitation and related management technology in Suzhou Creek YIN Haowen, LI Kang, CHEN Xiaoqian Bioassay and safety.

Study on the goal of ecological rehabilitation and related management technology

in Suzhou Creek

YIN Haowen, LI Kang, CHEN Xiaoqian

Bioassay and safety assessment laboratorySAPM

2010/04

环境与职业医学国际研讨会 ·2010· 都江堰

Set up a clear and operable management goal system for ecological rehabilitation, include short-time, medium-term and long term goal, in Suzhou Creek. All of these work is based on the research which was carried on between 1960’s and 2008

The object of the project

Confirm with spatial background in eco-rehabilitation Data collection (in situ test) The character identification with spatial data sets

Confirm with temporal background in eco-rehabilitation Analysis of historic data (from 1960’s) The verification of historic dada (in situ test) Finding out the key population concerned ecological

rehabilitation at background lever

Research program

The stages of ecological rehabilitation in the creek Ecological characters in different stage How to assess these characters?

Rehabilitation goal and partitional principles Fish community and it’s quantitative study Microbe population indicator The standardization with working method for

monitoring and assessing

Research program

The partitional system with ecological rehabilitation in Suzhou Creek

excellent —— Comparable to the best situations without human disturbance; all regional expected species for habitat and stream size, including the most intolerant forms, are present with a full of array of age(size) classes; balanced trophic structure. Class 1

good ——The values of the biological quality elements for the surface water body type show low levels of distortion resulting from human activity, but deviate only slightly from those normally associated with the surface water body type under undisturbed conditions. Class 2

fair ——The values of the biological quality elements for the surface water body type deviate moderately from those normally associated with the surface water body type under undisturbed conditions. The values show moderate signs of distortion resulting from human activity and are significantly more disturbed than under conditions of good status. Class 3

Partitional system -- ceocolog part 1

poor —— Waters showing evidence of major alterations to the values of the biological quality elements for the surface water body type and in which the relevant biological communities deviate substantially from those normally associated with the surface water body type under undisturbed conditions, shall be classified as poor. Class 4

bad —— Waters showing evidence of severe alterations to the values of the biological quality elements for the surface water body type and in which large portions of the relevant biological communities normally associated with the surface water body type under undisturbed conditions are absent, shall be classified as bad. Class 5

Partitional system -- ceocolog part 2

integrity

structure and function

self-purification

The general principals in assessing the course of ecological rehabilitation in Suzhou Creek

composition of living things microbe self-purification Hydromorphological elements Physical and chemical index pollutant

scoring each parameter and use the worst rating method to assess the ecological situation of water body.

Parameters of assessment

scientificity— combining real eco-condition of the creek with current evaluation method in EU and USA to set up eco-rehabilitation assessment system of Suzhou Creek

operability— current local technology lever should support such a advanced system

openness— this eco-rehabilitation assessment system is an opening profile, the parameter and new technology will be added as the situation of eco-rehabilitation of creek is developing

What kind of criteria used in constructing of eco-assessment system?

hydrophyte benthic invertebrates fish — integrity

Why should we choose fish?1. fish is on the top of food chain of creek ecosystem

2. It’s change is influenced by habitate, including physical,chemical and biological condition

3. Compared with other methods, fish taxology relatively suitable (local ability)

4. A highlight of public concern

Composition of aquatic living things

Fecal bacteria eco-type of bacteria bacteria toxicity

the fingerprint of microbe community

microbe

the lag phase the ability of inherent biodegradation of creek

water

（ following referred to as “self-purification” ）

Self-purification

Fish — number of species is low and the trophic structure is not integrity seriously

Microbe — heavy Fecal pollution and moderate eutrophication

self-purification — this kind of ability is decrease in recent years

less submerged plant, less invertebrates species and no macrophyta

partitional class is 4 (poor)

Evaluation results of Suzhou creek in 2008

Short-term — total number of fish will be increased and the invertivore increase in the proportion of individual ； fecal bacteria reach the recreational water standard class C which is suggested by WHO； have a stable value on self-purification。

Medium-term — more fish species occurrence in the creek and set up a Reasonable trophic structure in community. Intolerant fish species occurrence; fecal bacteria reach the recreational water standard class B which is suggested by WHO, the assessment result of fecal pollution reach medium lever; ability of self-purification increas.

long-term — the habitate of intolerant fish species will be set up and fish community constituted by various age population; fecal bacteria reach the recreational water standard class A which is suggested by WHO, the assessment result of fecal pollution reach good lever； less heterotrophic bacteria and self-purification ability will be moderate.

The goal of eco-rehabilitation in Suzhou Creek

Parameters assessment in eco-rehabilitation of

Suzhou Creek

fish communities survey

Fish composition and classing Excellent——comparable to pristine conditions,

exceptional assemblage of species， balanced trophic structure.

Good——decreased species richness, intolerant species in particular.

Fair——fair intolerant and sensitive species absent; skewed trophic structure,increasing frequency of omnivores and tolerant species.

Poor——top carnivores and many expected species absent or rare; omnivores and tolerant species dominant.

Very poor——few species and individuals present; tolerant species and exotics dominant; diseased fish frequent.

Assessment method

Speciese compositiom, Dominant species analysis.

Biodiversity. Composition of fish communities and it’s

integrity assess.

IBI — index of biotic integrity

Data collection

historical data

the data of 1960’s-1980’s are from Shanghai Museum (whole creek)； B. C. Zhou, 2001(whole creek)；X.H. Chen, 2006(two section)

historical data are very valuables and import, we get the baseline of fish communities from these data set.

Data validation in situ (sampling of whole creek in Oct.2008)

Sampling map

SS1： BH； SS2： HD； SS3： HC； SS4：北 BXJ； SS5：WNL； SS6： ZJL

Distribution of biomass

Community character of each section

BH — get the maximum value in biomass and number of individuals, these species should be consided as native species.

BXJ — this is a intersection (suzhou creek and Mudu creek), so have more species but less individuals compared with upstream. The habitate is not suitable to crap, catfish and bream, because of no aquatic weed.

WNL — less species with fish and the lowest biomass in whole creek. There are mosquito fish, Loach and Hemiculter bleekeri in this section

ZJL — most of species in here are not native except mosquito fish, loach and snakehead. Those are typical tolerant fish species and other species, such as crucian carp, bighead, are from Huangpu River.

Population distribution of fish assemblage(order)

5 orders, 7 families and total of 19 speciesCypriniformes (14) Siluriformes (2) Cyprinodontiformes (1)Mugilliformes (1) Perciformes (1)

Species distribution in the creek

Some of species are occurenced in the whole creek, such as crucian carp, Pseudobrama simony, Pseudorasbora parva and Hemiculter leucisculus.

Carp, bream and Culter dabryi, as large species, are living in the upstream(rural area)

mosquito fish, loach and Hemiculter bleekeri, as small specie, are occurrence in the downstream(urban area)

feeding habits

The structure of food chian is very simple and vulnerable. Primary and secondary consumer are main component, and few of the species preyed on fish and shrimp

In primary consumer, most of them eat algae and debris, few of herbivore.

The feeding structure is more simple in downstream, most of species are zooplankivores and detritivores (larva of insect).

Hemiculter leucisculus

This is a dominant species in the creek. It occurrence at BXJ and upstream.

Pseudobrama simony

It is also a dominant species, but occurence in the whole creek. It is omnivorous, pelagics, pollution-tolerant and native.

Vulnerable structure of Pseudobrama simony population

• There are a clear increase with specise at BXJ in 2008, such as carp and bream.

• only 9 individuals of Pseudobrama simony were captured in 2001 and all of them are living in the upper course (over HC), but in 2008, it is occurenced in the whole creek. It is dominant species

The spatial change of fish assemblage

The total catch of upper cause in 2008 is much lower than those in 2001.

Lost specise Cyprinidae: gobioninae 鮈亚科 acheilognathinae 鳑鲏亚科 These species were catched little in 2001 (not above

5 individuals)

The temporal change of fish assemblage

IBI

Excellent 53--55Good43--47Fair35--39Poor23--29Very poor11--17

Metric Scoring

criteria5 3 1

Species richnessand composition Total number of fish species >16 8--16 <8

Number of benthic species >5 3--5 <3Number of water column species >11 5--11 <5Number of intolerant species >3 2--3 <2% of individuals as tolerant species <5 5--20 >20

Trophic composition% of individuals as omnivores <20 20--45 >45% of individuals as native insectivores >45 20--45 <20% of individuals as native carnivores >5 1--5 <1

Fish abundanceand condition CPUE >47 16--31 <16

% of individuals as exotics 0 0--1 >1% of individuals with disease, tumors, fin damage and other anomalies

0 0--1 >1

Integrity class of Suzhou creek

Sites SS1 SS2 SS3 SS4 SS5 SS6Total number of fish species 1 3 1 3 1 3Number of benthic species 1 1 1 3 1 1Number of water column species 3 3 3 3 1 3Number of intolerant species 1 1 1 1 1 1% of individuals as tolerant species 1 3 1 1 1 1

% of individuals as omnivores 1 1 1 1 5 5% of individuals as native insectivores 1 1 1 1 1 1

% of individuals as native carnivores3 5 3 5 1 3

CPUE 5 1 1 1 3 3% of individuals as exotics 5 5 5 1 1 1

% of individuals with disease, tumors, fin damage and other anomalies

5 1 5 5 5 1

IBI Score 27 25 23 25 21 23Integrity class poor poor poor poor poor poor

Short-term — species increase, especially pollution-tolerant and sensitive species. the invertivore increase in the proportion of individual.

Medium-term — more fish species occurrence in the creek. The sensetive species occurrence and set up a Reasonable trophic structure in community (Omnivorous and pollution-tolerant species decrease). Prey species occurrence.

long-term — fish population constituted by various age individuals.

Rehabilitation of fish assemblage

The native fish species is from Tai river basin. Most of them are small size and suitable to habitate which is low flow and plentiful weed.

The concrete bank are builted both of side in the creek and flow rush the bank with tide. No any fish “shelter” in most of river reach.

The fish got in ZJL are all under concrete column of abandoned pier. mosquito fish often hide in the recess of bank in which the flow is slow.

This is the one of reason for Pseudobrama simony to be a Dominant in Suzhou Creek.

The fish community is influenced by river bank seriously

BH， there are few fish in new landscape

HD， Terrestrial vegetation zones couldn’t reach water body

The fish community is influenced by river bank Seriously

WNL, concrete river bank and flow with waves rapidly. Fish couldn’t stay here

ZJL, The fish got in ZJL are all under concrete column of abandoned pier.

The fish community is influenced by river bank Seriously

BH, shallows and weeds; quantity of fish.

The fish community is influenced by river bank Seriously

Fish community is useful tool to indicator the course of eco-rehabilitation. It is effective to assess different stage of rehabilitation by IBI in Suzhou Creek.

The planning and action of periodical ecological monitoring must be organized by authorities. Monitoring method should be standard and keeping data available.

Based on periodical monitoring, some ecological intervention can be conducted in a timely manner to keeping the right direction of eco-rehabilitation at Suzhou Creek.

Summary

The status of micro-organismsin the eco-rehabitation of Suzhou Creek

Indicator 1 - fecal bacteria For the class 2 contact, the demand of environmental protection

and landscape, water quality limited to fecal coliform as 1000cfu/ml, enterococci as 1000cfu/100ml

Based on WHO microbiological safety evaluation, the upper reaches of the Suzhou Creek is belong to class C (5-10% risk of acute gastroenteritis ,1.9-3.9% acute febrile respiratory disease), downstream is class D (10% of the gastroenteritis risk, 3.9% acute febrile respiratory disease).

Based on WHO Fecal pollution class, it’s belong to poor and very poor. So the water in Suzhou river can not be contacted with human body.

Now the ongoing recreational activities, such as dragon boat races on Suzhou Creek, is not full-body contact, but still a near water contact, so there is a real risk on gastro-intestinal diseases if someone make such activities in Suzhou Creek.

WHO microbial indicators of recreational water

Table 1 Landscape recreational water quality standards

Classification standard value

A B C

Total coliform，个 /L ≤1000

Fecal coliform，个 /L

≤2000

The People's Republic of China National Standard - Landscape recreational water quality standards Approved by the State Environmental Protection Agency 1991-03-18 implemented by 1992-02-01

Goals Short-term:

Enterococci and other fecal bacteria indicators in line with WHO microbiological quality of class C.

Upstream and downstream of fecal pollution in the same category. Medium-term:

Enterococci and other fecal indicators reach the calss B of fine standards.

Fecal pollution of the river-wide classification to achieve "moderate" level.

Long-term: Enterococci and other fecal indicators reach class A of standards. Fecal pollution of the river-wide achieve "good" level.

Indicator 2 - functional bacterial population

functional bacteria: heterotrophic bacteria, anaerobic bacteria and autotrophic bacteria are the best indicators for environmental changes in Suzhou Creek.

The relationship about heterotrophic bacteria and eutrophication is in the table below:

Now, Suzhou river belong to meso-saprobic water.

水质(water quality)

异养细菌总数（个 /ml ）The total number of heterotrophic bacteria

BOD （ m

g/L ）

强污浊水 (High dirty water) 100， 000以上 100~80

中污浊水 (Middle dirty water) 100， 000~10， 000 80~55

弱污浊水 (Low dirty water) 10， 000~1， 000 55~30

亚清水 (sub-clean water) 1， 000~150 30~10

清水 (clean water) 150以下 10~0

Short-term The total number of heterotrophic bacteria

decreased to between 103~104

Middle-term The total number of heterotrophic bacteria

decreased to between 102~103

Long-term The total number of heterotrophic bacteria

decreased to 150 below

Goals

Bacteria instructions of river pollution classification

Total colifor

m

E.coli

Several current indicator of microbe in water quality assessment

indicator adventage

Enterococcus•human health indicators in Seawater and freshwater. •Remaining longer in the water and sediment.

Fecal coliformTotal coliform

•Latest fecal contamination can be directed•Not suitable for a number of water bodies; growth in soil and water

E. coli Human health indicators in freshwaterBe able to direct the latest fecal contamination.Be used for fecal contamination tracing.Able to quickly detect

E. coli, enterococcus in Suzhou Creek is not only far exceeds the number set by WHO and the USEPA recreational water limits(the minimum required for boating, fishing function), but also not reached the chinese standards.

E.coli and Enterococcus of BXJ following are higher than the upper, Beixinjing is particularly prominent.Monitoring show that there are some uncontrolled pathogenic sources in the creek.

fecal bacteria in the creek

Significance of Functional bacteria for goals of eco-rehabilitation

Heterotrophic bacteria

• Indicate eutrophication

Anaerobic bacteria

• Indicate river pollution

Autotrophic bacteria

• Indicate river self-purification capability

Heterotrophic bacteria

Autotrophic bacteria

Anaerobic bacteria

Functional bacteria - autotrophy, anaerobic, heterotrophic bacteria count

Anaerobic bacteria in BXJ is the highest, heterotrophic bacteria in ZPL(ZJL) is the highest, autotrophic bacteria in HC is the highest.

The nitrogen-containing pollutants in the downstream is very high, and chemical analysis also shows that there are high NH3-N, and NO2-N and low dissolved oxygen in the downstream.

functional bacteria in creek

comparing functional bacterial data in different year:

the highest value got in 1998, declined in 2001 and 2002, and bounced back in 2008.

Method for monitoring and assessing the self-purification ability of Suzhou Creek

Microbial self-purification plays an very important role in self-purification of water bodies

Characteristics of microbial self-purification in various stages

Initial stage Persistent stage Final stage

Heterotrophic bacteria amount

Lag phase of degradation

degradation rate

Persistently increased, reaching the maximum value

Continuously shortening, reaching the minimum value

Persistently increased, reaching the maximum value

Begin to decrease

Begin to prolong gradually

Begin to decrease

Persistently decreased, reaching the minimum value

Reaching the maximum value

Persistently decreased, reaching the minimum value

Dissolved oxygen ↓ BOD:COD↓

Dissolved oxygen, BOD:COD return to normal

Water quality gradually improved

The stage

of Suzhou Creek

The main critiria of self-purification in Suzhou Creek is to assess it’s ability about organic pollutants assimilation and degradation at the present stage.

Available parameters

-lag phase of degradation: which indicates the adaptation of microbe community to pollutants

-degradation rate: which indicates the degradation ability of microbe community

standard manometric respirometry method （28-d ）

Sodium acetate

Diethylene glycol

Paraldehyde

The creek water as a sample

Data analysis method First-order kinetics is applied to determine the rate of oxygen

consumption and CO2 formation, the following non-linear fit model is used for biodegradation curves with a flat lag phase

Y： the percent theoretical or chemical oxygen demand, resp. percent CO2 formation（%ThOD、%COD、%ThCO2）t： time（ days）A： the asymptote of curve（%ThOD、%COD、%ThCO2）K： the first-order rate constant（ days-1）C： the lag period（ days）First-order rate constants can be used to calculate the half-life （ t1/2） for the test chemical by the

equation:

kt

2ln2/1

sodium acetate , diethylene glycol and paraldehyde were screened by QSAR and confirmed their biodegradable ability is diminishing one by one.

Three standard reference chemicals , sodium acetate, diethylene glycol and paraldehyde, were screened out to evaluate the microbial self-purification ability of Suzhou Creek

In case there are any changes of microbial degradability in a river reach , related degradation parameters will be changed.

The lag phase of three kinds of chemicals was prolong in 2008 compared with those in 2006, it showed that the microbial adaptation weakend in 2008.

In 2006, half-lives of 3 chemicals were less than 2 days in both the upstream and downstream, while those of diethylene glycol and paraldehyde were prolong in 2008, especially the half-live of paraldehyde in downriver was 2.3 days.

Comparison analysis between 2006 and 2008 show that both of the degradation rate of sodium acetate, diethylene glycol and paraldehyde of upstream and downstream water samples were decreased in 2008, especially for the degradation of paraldehyde was markedly reduced from 77.82% and 88.73% in 2006 to 35.83% and 65.86% in 2008 , respectively.

Above all, the self-purification capacity and microbial adaptation of Suzhou Creek has been comprehensively weakened in 2008.

Summary

The water samples from Suzhou Creek are collected periodically. Self-purification testing, with various reference, are performed according to a standard manometric respirometry test. By compareing the changes of lag phase and biodegradation rate of samples in different times and sites to assess the microbial adaptability and self-purification capacity in different creek segments.

The external input of organic pollutants in 2008 has no obvious changes by evaluated the chemical parameters (COD,BOD ……). Nevertheless, the self-purification capacity of HD (upstream) BXJ, JSL (downstream) decreased sharply.

The self-purification capacity of upstream has declined obviously into an warning level. It shows that microbe community has been destructed by exogenous chemical substances.

The adaptation of downstream water was slightly higher than 2006 to general organic pollutants, but the self-purification capacity for non-degradation organic compound was declined.

Compared with 2006, the self-purification capacity of Suzhou Creek has been comprehensively weakened, it is a signal to warn the ecosystem deterioration.

Thanks for your time!