基于InVEST模型的黄河流域土壤侵蚀评估及其时空变化

Soil erosion and its temporal-spatial variation in the Yellow River Basin based on the InVEST model

运用InVEST模型评估黄河流域2000、2005、2010和2018年土壤侵蚀量并分析时空变化特征.结果表明,18 a间,黄河流域土壤侵蚀总量共减少8.4×10^(7)t,土壤侵蚀模数共减少87.42 t/(km^(2)·a),减少约16.69%,流域土壤侵蚀状况趋于改善;侵蚀模数高值区域主要分布在黄河流域上游,低值区域主要分布在黄河流域中、下游区域,侵蚀模数下降区域主要在黄河流域中游地区;全流域土壤侵蚀量最大的地类为草地,土壤侵蚀模数最大的地类为未利用地;坡度为8°~15°和15°~25°的区域以及海拔在1000~1500 m和4000 m以上的区域土壤侵蚀量最大,全流域平均土壤侵蚀模数随坡度的增大而增大,随海拔的上升呈先增加后减少的变化特征.黄河中下游水土流失治理措施取得明显成效,黄河上游土壤侵蚀应引起重视.

The InVEST model was used to evaluate the soil erosion in the Yellow River Basin in 2000,2005,2010 and 2018,and the temporal-spatial variations of soil erosion were analyzed.The results showed that,during the study periods,the total amount of soil erosion in the Yellow River Basin decreased by 8.4×10^(7)t,soil erosion modulus decreased by 87.42 t/(km^(2)·a),and soil erosion status decreased by16.69%,i.e.tending to improve;the areas with a high erosive modulus were mainly distributed in the upper reaches of the Yellow River,areas with low values mainly distributed in the middle and lower reaches,and areas with a decreased erosive modulus mainly located in the middle reaches;the land type with the largest soil erosion in the whole basin was grassland,while that with the largest soil modulus was unused land;the average soil erosion modulus of the whole watershed increased with the increase of slope,and the soil erosion intensity increased first and then decreased with the elevation.The obvious effectiveness had been achieved of the control measures of soil and water loss in the middle and lower reaches of the Yellow River,and attention should be paid to soil erosion in the upper reaches.