填海造地导致海湾生态系统服务损失的能值评估——以套子湾为例

Emergy appraisal on the loss of ecosystem service caused by marine reclamation:a case study in the Taozi Bay

评价填海造陆导致的海湾生态系统服务价值损失成为海洋资源配置和调控沿海经济发展与环境保护的重要手段。运用能值分析方法,结合海湾生态系统特点,针对填海工程造成的供给、调节、文化、支持4类生态系统服务损失构建了能值估算模型,并以烟台套子湾填海工程为例,分析了该湾生态系统服务的损失情况。结果表明,该湾供给服务损失最大,全部生态系统服务年能值损失为3.32×1024sej/a,海域使用年限内(50a)的能值货币价值损失总计2.28×1014元,单位面积的能值货币价值损失1.73×1012元/hm2,远远高于依据现行的生态补偿评估方法计算的结果。该能值模型对生态系统服务损失的评价更为客观合理,适用范围较广,为完善控制填海活动的经济体制建设、促进沿海区域的可持续发展提供依据。

It is an important method to evaluate the loss of marine ecosystem service caused by marine reclamation from the sea, in order to allocate marine resources and regulate development of coastal economy and environmental protection. The traditional method of economic evaluation has some shortcomings, such as partially stressing the loss of economic benefit and ignoring the characteristics of ecosystem service including public goods properties, ineradicable externalities and difficulty of monetization for non-market part. These shortcomings will be modified by the emergy analysis which could illustrate the real wealth of ecosystem service by standardizing and accounting the energy and materials invested directly and indirectly from both natural environment and human society. In the present study, emergy estimating model was developed and based on the structural and functional characteristics of gulf ecosystem to evaluate the loss of ecosystem service caused by marine reclamation, which includes 4 categories of ecosystem function in detail such as Provision （i. e. food production, raw materials）, Regulation （i. e. climate regulation, waste treatment, disturbance regulation ）, Support （i. e. nutrient cycling, biodiversity support） and Culture （i. e. research ＆ education, tourism ＆ recreation）. The marine reclamation in the Taozi Bay, Yantai City, was presented as a case in the paper, which includes the fishing port project of Yantai Development Zone and the first and second phase projects of Dayu Shipyard. Results showed that the total loss of functional service was 3.32x10^24 sej per year, and the loss summarized by emdollar value was 2.28x10^14 yuan during the whole lifetime （50 years） of sea area utilization, and the average loss of emdollar value was 1.73 x 10^12 yuan per hectare. Thefunctional category of provision absolutely dominated the loss due to high intensification and solar transformation of the shellfish culture in original waters, followed by supporting service, regulating service and cultural service. In detail, the direct loss of emdollar value of food production was about 4.56 x 10^12 yuan per year in specific sub-function category, and the loss of biodiversity support and disturbance regulation was about 5.39 x 107 yuan per year and 1.58 x 107 yuan per year, respectively. The estimated emdollar value was significantly higher than the ecological compensation resuhsl. 41 x l07 yuan according to the ＂Construction Projects on the Marine Biological Resources Impact Assessment Technical Regulations＂, which demonstrated that the current ecological compensation method underestimated the total loss of ecosystem service and partially reflected the effect of marine reclamation on gulf ecosystem. It is urgent to improve the evaluation method in order to effectively inhibit the unrestricted reclamation and protect the gulf environment. The successful evaluation in the case using the emergy model demonstrated some advantages. Firstly, it is capable of supporting the cumulative impact assessment at both the temporal and spatial scales. Secondly, it can be used to compare the emdollar value with the current monetary result based on the traditional economic valuation method. Thirdly, it has a wide application to evaluate the ecological cost happened in various sea-related construction projects, such as port, scenic spot, oil platform. Therefore, the compensation for utilization of offshore environmental resource, economic institution-building for reclamation control and sustainable development in coastal regions would be evaluated scientifically. However, the model still need to be improved in some aspects including the reasonable selection and calculation of solar transformation, the evaluation method of cultural service loss, and the dynamic simulation of the service loss before and after reclamation.