【摘要】 通过分析百年尺度上中国西北降水空间分布规律和沙漠界线、农牧交错带界线的演变规律,认为:①干旱、半干旱是西北地区的主要气候特征;②生态系统非常敏感和脆弱;③在维持温饱和经济利益驱动下建立的农、牧业产业结构,是造成西北环境恶化的最主要的原因。更多还原

【Abstract】 By analyzing the change laws of the spatial-temporal distribution of precipitation,the desert borderlines and the ecotone between agriculture and pasture,it is suggested that the arid and semi-arid is the main climatic characteristic in northwest China.The ecosystem is very sensitive and weak.The structure of agriculture and pasture established aiming at keeping the people having adequate food and clothing and driven by economic interests is the main cause of worsening ecosystem and environment.更多还原