重庆市土壤保持服务空间分布及影响因素分析

Spatial Distribution and Influencing Factors Analysis of Soil Conservation Services in Chongqing

土壤保持服务能够削弱和改善土壤侵蚀,对其空间分布特征及影响因素进行分析,可提高土壤保持能力,减少区域水土流失。首先,基于修正通用土壤流失方程(revised universal soil loss equation,RUSLE)模型和生态系统服务和交易的综合评估(integrated valuation of ecosystem services and trade-offs,InVEST)模型估算研究区土壤侵蚀量;其次,选用精度更高的土壤侵蚀估算模型评价研究区土壤保持服务;最后,采用多元线性回归、地理探测器等方法探讨影响研究区土壤保持服务空间分布的主要因素。结果表明:RUSLE模型估算结果与研究区实际土壤侵蚀模数差值为201.02 t/(km^(2)·a),精度较低,InVEST模型估算结果与研究区实际土壤侵蚀模数差值为33.11 t/(km^(2)·a),精度较高;研究区土壤保持总量为13.01×10^(8)t,其中土壤保持能力较强的区域在研究区东北以及西南方向,而研究区西部、中部和东南部土壤保持能力较弱;影响土壤保持服务的气候因素主要为降水和气温,影响土壤保持服务的景观指数主要为蔓延度指数、景观分离度、分离度指数和香农均匀度指数。研究结果可为生态系统服务的可持续发展提供科学依据。

Soil conservation services can weaken and improve soil erosion,and by analyzing its spatial distribution characteristics and influencing factors,it can improve soil conservation capacity and reduce regional soil erosion.Firstly,the amount of soil erosion in the study area was estimated based on the reviewed universal soil loss equation(RUSLE)model and the integrated evaluation of ecosystem services and trade offs(INVEST)model.Secondly,a more accurate soil erosion estimation model was used to evaluate soil conservation services in the study area.Finally,the main factors affecting the spatial distribution of soil conservation services in the study area were discussed by means of multiple linear regression and geographical detectors.The results show that the difference between the estimated results of the RUSLE model and the actual soil erosion modulus in the study area is 201.02 t/(km^(2)·a),which is of low precision.The difference between the estimated results of the InVEST model and the actual soil erosion modulus in the study area is 33.11 t/(km^(2)·a),with high precision.The total soil conservation in the study area is 13.01×10^(8)t.The areas with strong soil conservation capacity are in the northeast and southwest of the study area,while the west,middle and southeast of the study area have weak soil conservation capacity.The climatic factors affecting soil conservation services are mainly precipitation and temperature,and the landscape indices affecting soil conservation services are mainly sprawl index,landscape segmentation degree,separation index and Shannon uniformity index.The research results can provide a scientific basis for the sustainable development of ecosystem services.