中国水土保持生态服务功能价值估算及其空间分布

水土资源是人类赖以生存的重要的物质基础,水土保持作为人类对生态系统干预的有效手段,其生态服务功能价值也受到越来越多的重视。论文选取土壤保持价值和涵养水源价值两项指标,结合遥感数据、气象数据以及地面数据,对原有的基于遥感的水土保持生态服务功能价值估算模型进行改进,以期更好地体现水土保持生态服务功能应有的价值。论文运用改进后的模型估算2001年全国水土保持生态服务功能价值达16 760.55×108元,基本呈自东南向西北递减趋势。

Value Estimation of Conserving Water and Soil of Ecosystem in China

Soil and water resources are important material basis for human life. As an effective means of human intervention, the value of soil and water conservation ecosystem services has been given more and more attention. In this paper, the value of conserving soil and fertilizer and the value of conserving water were selected as the indices of the value of conserving soil and water. Integration of remote sensing data, meteorological data and ground data, the original soil and water conservation service evaluation model is improved. The value of conserving soil includes three types, i.e. conserving soil fertilization, reducing surface soil loss and alleviating sedimentation. As the key point of estimating the value of conserving soil, in this paper, the USLE model was improved to estimate the quantity of soil conservation. The value of conserving water was estimated by the method of shadow engineering through expanse of building reservoir with the same water storage. Utilizing RS and GIS technique, quick estimation can be achieved through IDL programme. There are some uncertainties existing in this estimation. Firstly, the basic data are not completely consistent with the actual land surface. Secondly, some experience models adopted are difficult to reveal the soil erosion physical process.Result shows the value of conserving water and soil of ecosystem in China was 16760.55 billion yuan in 2001, including 9663.50 billion yuan of conserving soil and 7096.55 billion yuan of conserving water. According to spatial distribution, it descended from south to north. According to land cover, evergreen broadleaf trees were the highest of average value, water body less, barren and ice the lowest. According to terrain, with the higher altitude, the value of conserving soil and water showed a downward trend. According to administrative, Guangdong was the highest of average value, Xinjiang the lowest, and provinces in eastern and southern parts of China were higher than others. It is difficult to get the measured data to verify the estimation result and has no comparability to the related research, based on different methods and different indices. In the future research, the verification needs to be strengthened.