地域主体功能导向下攀西干热河谷区土壤侵蚀分析及预测OA

[Objective]This study examines soil erosion and its spatiotemporal evolution in the Panxi Dry Valley and simulates future land use under the framework of regional principal functional zoning policies,providing forward-looking theoretical support for the construction of the"Second Granary of Tianfu"and promoting coordinated ecological protection and regional development.[Methods]Using the Panxi Dry Valley as a case study,a coupled MCCA-CSLE-LMDI model was constructed based on land use changes from 2010 to 2023 to predict the land use patterns and soil erosion evolution for 2035 under natural development and policy-oriented scenarios.[Results](1)The results indicated that from 2010 to 2023,forest,cropland and grassland collectively accounted for over 95%of land use,with a predominance of ecological and agricultural functions,while construction land and water bodies continued to expand.(2)Between 2023 and 2035,under the natural development scenario,construction land was projected to increase by 255.04 km² and cropland to decrease by 42.49 km²,whereas under the policy-oriented scenario,construction land expanded by only 80.57 km² and cropland increased by 72.82 km².(3)The overall soil erosion modulus decreased,with the policy-oriented scenario exhibiting a 0.829 t/(hm²·a)lower soil erosion modulus than the natural scenario,an increase of 158.86 km² in micro-erosion areas,and a reduction of 329.89 km² in severely eroded zones.(4)According to the LMDI decomposition,the suppressed areas of the B,E and T factors under the policy-oriented scenario reached 29 343.05,27 342.16 and 29 612.16 km²,respectively,which were significantly better than those under the natural scenario.[Conclusion]In the Panxi Dry Valley,soil erosion under the policy-oriented scenario is predominantly slight with an increasing proportion of affected area,while severe and higher erosion zones are markedly reduced.Compared with the natural development scenario,it more effectively mitigates erosion intensity,indicating that policy regulation plays a vital role in safeguarding farmland security and advancing the construction of the"Second Granary of Tianfu".