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At present,academics on the ecological services value research focus on the positive aspects,while the negative service values,such as environment cost,is received little attention.Pond aquaculture performs multiple functions,including aquatic products supply,air quality adjustment as well as culture service and so forth.As a kind of special ecological system,the pond aquaculture also has the environment cost in its production process.A clear cognition of the positive and negative ecological services values in pond aquaculture will be a great significance to avoid the blindness and short-term version in the process of production,keep the development of pond aquaculture sustainable and promote the development of aquaculture in harmony with the environment protection.This paper firstly adopts double-bounded dichotomous contingent valuation method(CVM) and random cluster sampling method to attain the local residents′ willing to accept(WTA),354 questionnaires were sent out and 340 effective questionnaires were returned,the effective response rate was therefore 96.05%.Then the paper adopt Logit and Biprobit regression models of econometrics and STATA10.0 software was utilized for analyzing the environment cost of pond aquaculture in the DianShan Lake,Shanghai.Through these methods adopted,the paper has summarized these results as following: 1) The ecological compensation E(WTA) standard of Shanghai residents for the environment pollution damage is 104.89 RMB Yuan per person in Logit model and 121.89 RMB Yuan per person in Biprobit model;2) In 2010,the total pond aquaculture environment cost is about 19.8226 million Yuan,namely 5105 RMB Yuan · a-1 · hm-2);3) The latest research released that several economic social factors such as the income of the household,education background and age lay a great influences on residents′ willingness to accept the ecological compensation,but these factors will cause no strict trend influences on the residents′ WTA at present.Such as the income of the household,education background of residents affect the E(WTA),which shows a positive effect on the relationship of E(WTA) standard.The 18—45 years old residents pay more attention to the environmental protection.If government takes the ecological compensation policy,they may be the main stakeholders.The paper also mentions the discussions: 1) Because these social economic factors have common influences on the E(WTA) standard of residents,but the size and direction of these influences are not absolute,it needs to do a further study based on the actual situation to establish a stable structure model to determine the size and direction of these influences;2) By the LR and WALD test,the research indicates that the double-bounded dichotomous discrete CVM has a stronger stability than the single-bounded dichotomous discrete CVM,thus the double-bounded dichotomous discrete CVM can become a relatively stable research method for ecological system service value study;3) The environment property right should be the applicable standard to WTA and WTP.Meanwhile,improving the questionnaire design accuracy,adjusting the research course etc can overcome the differences between WTA and WTP effectively;4) Government should make and conduct a make-up policy for ecological compensation according to the real situation in order to achieve the environmental equity and sustainable development.

Studies on food supply values, the basis of eco-service values, and their factors of different pond aquaculture ecosystems are helpful to explain the influences of the inputted factors and their variations among these ecosystems and provide information for stakeholders to adjust their decisions and behaviors to increase their total eco-service values. On the basis of continued records from 2011 to 2012 of 18 ponds of three pond aquaculture ecosystems, namely Litopenaeus vannamei, Macrobrachium nippponensis and carp fresh water pond aquaculture ecosystems in Qingpu, Fengxian, and Jiading, three suburban districts of Shang, this paper analyzed the costs, returns, net food supply values and their regional and temporal fluctuations. The results showed that: (1) the net food supply values of the three ecosystems are 143252.4, 135883.7, and 52623.1Yuan/Ha in 2011 correspondently, with the Litopenaeus vannamei pond aquaculture ecosystem (LVPAE) ranking highest and the carp pond aquaculture ecosystem (CPAE) lowest among them, and the trend was same in 2012, but the values decreased than that of 2011 with the rate of 30.0%( LVPAE), 38.0 %( Macrobrachium nippponensis pond aquaculture ecosystem, MNPAE) and 13.7 %( CPAE). (2)The dominant factors of the net food supply values of these ecosystems are the produce price and variable costs; fry and feed costs are the main variable factors producing the noticeable difference among the ecosystems. (3) The cost-benefit ratio of per unit product of the CPAE, LVPAE and MNPAE changed from 27.5%,91.7%,129.0% in 2011 to 23.0%,73.8% and 63.8% in 2012, with the CPAE ranked lowest among them in both years.(4) For all the three ecosystems, their net food supply values may not always change in same trends with their net eco-service values, if stakeholders want to keep an balance between these two types of values, MNPAE should be encouraged in these districts.