【摘要】 定量区分气候和人类因素在黄土高原西北部植被变化中的贡献率,对该区正在开展的退耕还林(草)工程具有重要指导意义。"回归残差法"是当前该领域使用的主要方法之一,但它有混淆气候变化和人类活动作用的内在风险。本文提出一种旨在克服该缺陷的"去趋势回归残差法",即利用去趋势之后的植被和气候数据建立回归模型,再将原始气候数据代入模型得到模拟植被并进行残差趋势分析。基于SPOT VEGETATION NDVI时间序列的研究结果显示:(1)在气候变化趋势性明显时,"去趋势回归残差法"优于常规方法;(2)近15年黄土高原西北部植被活动整体上呈增强态势,这种增强主要由人类因素所致,贡献率达92%,气候变化的作用较弱,贡献率仅为8%。更多还原

【Abstract】 To quantitatively differentiate the contributions of climate and human being to vegetation variation on the northwest of loess plateau is significant to the ongoing vegetation restoration projects.This paper puts forward a method of "detrended regression residuals method"to eliminate the effect of a common trend.First use the trend-eliminated data of plants and climate to construct regression model and then use the original climate data to simulate the plants and conduct residual analysis.The spot vegetation NDVI based on the experiments of time series shows that,the"detrended regression residuals method"is superior to the conventional methods.The recent 15-year vegetation on the northwestern loess plateau activity has been generally bettering,due to a human contribution rate of 92%and a climate contribution of 8%.Meanwhile,the two effects showed great spatial heterogeneity.更多还原