基于多源遥感数据的生态系统保育土壤价值评估——以河北省北部四地市为例

The Evaluation of the Ecological Service of Soil Conservation Based on Multisource Remote Sensing Data:A Case Study of Four Areas in Northern Hebei

为了给合理地利用土地资源和科学地进行环境保护提供依据,利用多源遥感影像数据,结合气象数据、土壤属性数据与DEM,对河北北部地区生态系统的土壤保持量进行了评估,并参考《森林生态系统服务功能评估规范》,对生态系统保护土壤肥力的价值与固土价值进行了评估。结果表明,研究区2008年度生态系统的土壤保持总量达到7.55亿t,对应的价值量为1.08×104亿元。林地、灌丛及草地生态系统分别为平均土壤保持量与保持价值最大的3种生态系统类型,它们在区域土壤保持中起着重要的作用。从空间分布来看,研究区的中部山区,植被覆盖良好,土壤保持量及保持价值较高,而东西部平原及坝上地区,地势平坦,植被覆盖稍差,土壤保持量及保持价值均较低。中部山区虽然植被覆盖良好,但由于地势起伏大,容易发生水土侵蚀,因此加强中部山区自然植被的保护和建设,是减缓区域水土流失,提高生态系统保育土壤服务价值的关键。

Based on multi -source remote sensing data, rainfall data, DEM and soil property data obtained in northern Hebei, the authors used Universal Soil Loss Equation （USLE） to make a quantitative analysis of soil conservation capacities with the support Of GIS technique. Then the soil conservation capacities were converted into capital stocks by making reference to the Specifications for Assessment of Forest Ecosystem Services in China, which was stipulated on May 1, 2008. Two kinds of ecosystem service values were considered, i. e. , the value of preserved nutrient and the value of fixed soil. The results reveal that the total soil conservation capacity of northern Hebei was 7.55 ×10^8 t in 2008, and the corresponding value of this ecosystem service was 1.08 ×10^12 Yuan. The soil conservation capacities and soil conservation values of woodland, scrnbland and grassland are the largest three among the seven kinds of ecosystem values, so these three ecosystems play key roles in conserving soil in northern Hebei. The spatial distribution characteristics of soil conservation values of northern Hebei show that the average value of central mountain areas is higher than the average value of western plateau and eastern plain, because dense vegetation prevents soil from erosion in mountain areas and soil erosion intensity is slight due to flat terrain in the western and eastern parts. For solving the problem of soil erosion in northern Hebei, natural vegetation should be protected, especially in central mountain areas.