Lou, Yan , Wang, Jingpu , Chai, Yizhen , Tian, Lihui , Zou, Xueyong
2026-07-01 JOURNAL OF ARID ENVIRONMENTS 2026 236(卷), null(期), (null页)
Aerodynamic roughness (z0) reflects the extent to which surface roughness elements reduce wind erosivity, and accurate monitoring of z0 is crucial for soil wind erosion models. Spring is a period of high soil wind erosion risk in arid and semi-arid steppes in China. However, current z0 estimation models are mostly based on surface roughness features in summer and cannot represent actual spring surface conditions. Using four machine learning methods: eXtreme Gradient Boosting (XGBoost), K-Nearest Neighbors (KNN), Random Forest (RF), and Partial Least Squares Regression (PLSR), we evaluated the accuracy of z0 estimation models constructed based on photosynthetic vegetation (PV) and non-photosynthetic vegetation (NPV) parameters in spring (April-May). The NPV-based z0 model outperformed the PV-based z0 model, with the XGBoost_NPV-based z0 achieving the highest accuracy (R2 = 0.790, RMSECV = 0.113, rRMSECV = 0.452). From 2010 to 2022, daily spring z0 of Xilingol Steppe exhibited a decreasing trend, with a multi-year average of 0.38 cm. Spatially, z0 increased from southwest to northeast, and its stability ranked from high to low as: desert steppe, meadow steppe, typical steppe, and sandy steppe. These findings demonstrate the applicability of NPV parameters for estimating spring z0 and support long-term, large-scale monitoring of soil wind erosion.