古尔班通古特沙漠土壤水分含量与地形-植被因子关系研究OA

Soil moisture forms an essential component in the formation,transformation,and consumption of wa-ter resources.This study investigates soil moisture in fixed,semifixed,and mobile dunes of the Gurbantunggut Desert in Xinjiang,China.The relationship between moisture at different soil depths and topography-vegetation factors was analyzed using partial least squares structural equation model(PLS-SEM),random forest model,and Shapley additive explanations(SHAP)value analysis.The results showed that:(1)Except for soil moisture in the middle layer of semifixed and mobile dunes,the vertical distribution of moisture among dune types varied signifi-cantly.(2)Structual equation model indicated that the topography factor—height difference and vegetation fac-tor—shrub abundance—had the most pronounced impacts on soil moisture in fixed dunes;slope degree and shrub coverage were dominant factors in semifixed dunes,whereas topography and vegetation factors had relatively mi-nor effects in mobile dunes.(3)The interaction among key factors revealed that in fixed dunes,a combination of herb and shrub abundance>300 plants·m-2 and>2 plants·m-2,respectively alleviated water stress;in semifixed dunes,>200 plants·m-2 and>30%,respectively mitigated the adverse impacts of slope degree on soil moisture;in mobile dunes,maintaining herb coverage at>20%and biomass at>10 g·m-2 was necessary to enhance soil mois-ture content.These findings can help formulate refined management strategies for desertification control.