中国农业大学学报2025，Vol.30Issue(10)：25-37,13.DOI:10.11841/j.issn.1007-4333.2025.10.03
土壤全氮驱动因素分析及模型构建
Soil total nitrogen driving factor analysis and model construction:A case study of the Huangshui River Basin
摘要
Abstract
To better understand the drivers of soil nitrogen,maintain the stability of the ecological system in the Huangshui River Basin,this study based on a set of measured soilTotal Nitrogen(TN)data in the Huangshui River Basin,a hybrid model was developed using the random forest,Pearson correlation analysis,and multi-scale geographically weighted regression methods was adopted to analyze the driving factors of soil TN.The results show that:1)Soil TN exhibited a gradual increase from the southeastern to northwestern regions of the basin.High-value areas were concentrated in the northwestern high-altitude zones,while low-value areas sporadically occurred along the mid-to-lower reaches of the Huangshui River.2)The primary drivers were the annual mean temperature,pH,and distance to urban areas.There were differences in the magnitude and scale of the impact of various factors on soil TN.Feature importance from highest to lowest is:Annual mean temperature(78.5％)＞pH(6.9％)＞distance to urban areas(1.4％).Bandwidth from highest to lowest is:Annual mean temperature(278 km)＞distance to urban areas(85 km)＞pH(48 km).3)The hybrid model,using only three variables,achieved equivalent adjusted R2(0.41)to the original 19-variable model.It also outperformed the original model in terms of stability index AICc and effective degrees.The soil TN in the Huangshui River Basin displayed a belt-shaped spatial distribution pattern.Annual mean temperature,operating at larger spatial scales,was the dominant natural driver,while human activities exerted minor localized effects near urban areas.The hybrid model effectively reduced overfitting and has good applicability in this basin.This study provides a scientific reference for sustainable agriculture and ecological protection in the Huangshui River Basin.关键词
湟水河流域/土壤全氮/驱动因素/混合模型/随机森林/多尺度地理加权回归Key words
Huangshui River Basin/soil total nitrogen/driving factors/hybrid model/random forest/multiscale geographically weighted regression分类
农业科技引用本文复制引用
万成瑞,于茹月,盖建勋,徐圣贤,黄元仿..土壤全氮驱动因素分析及模型构建[J].中国农业大学学报,2025,30(10):25-37,13.基金项目
国家自然科学基金项目(U20A20115) （U20A20115）
