陕北农牧交错带50年来土地沙漠化的自然和人为成因定量分析  

Quantitative analysis of natural and anthropogenic effect on sandy desertification in the agro-pastoral transitional zone of northern Shaanxi Province in the near fifty years

作　　者：齐雁冰[1] 常庆瑞[1] 刘梦云[1] 刘京[1] 陈涛[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《中国水土保持科学》2011年第5期104-109,共6页Science of Soil and Water Conservation

基　　金：教育部博士点基金"陕北能源化工基地高污染风险区土壤地球化学垒研究"(20090204120036);国家自然科学基金"黄土高原植被恢复对有机碳影响机理及其碳储量估算研究"(30872073)

摘　　要：荒漠化的发生发展受自然及人为因素的共同作用,为了对自然及人为因素的贡献进行定量化分析,以陕北农牧交错带为研究对象,选择该区1949—2000年7个自然和人为因子,运用主成分分析方法,对土地荒漠化过程中的自然与人为要素作用强度进行量化分析。结果表明:1)陕北农牧交错带自1949年以来气候呈现暖干、冷湿交替过程,而未来气候将逐渐趋于暖干,但平均风速则呈现逐渐降低的趋势;人口和牲畜数量及工业总产值持续增长,人均耕地面积则持续下降,这些对荒漠化防治均是不利因素。2)在陕北农牧交错带荒漠化的发展过程中,自然因素的贡献率为13.06%,人为因素与自然因素综合作用的贡献率为73.51%。3)尽管自然及人为因素50年来的变化促进了荒漠化的发生发展,但自20世纪50年代开始的"三北防护林建设"和"退耕还林(草)工程"对阻止荒漠化的发展起到了关键作用。Desertification is a complicated process affecting by variety of natural conditions and human activities.In order to analyze the function of natural and human activity in desertification process,the agro-pastoral transitional zone of northern Shaanxi Province was selected as a case study area.By employing principal component analysis method,the seven factors during 1949 to 2000 were chosen,including temperature,precipitation,wind speed,population quantity,livestock quantity,cultivated land area and industrial gross output,to analyze the intensity of nature and human activity factors quantificationally.The results showed that： 1） Predictions call for the climate to become increasingly warmer and drier over the next several decades.The average wind speed decreased during the period.The population,livestock populations and gross industrial output increased significantly from 1949 to 2000,but the per capita cultivated land decreased significantly in the same period;2） In the desertification process,nature factors contributed to 13.6%,and human activity combining with nature factors contributed to 75.31% in the agro-pastoral transitional zone of northern Shaanxi Province;3） Fortunately,local officials have recognized the negative effects of desertification and paid more attention to controlling desertification.Planting shrubs to improve vegetation coverage is the main approach used for desertification control.Two projections have been applied to the agro-pastoral region of northern Shaanxi Province to control desertification： the ＂Three North Shelterbelt Program＂ and the ＂Grain-for-Green Project＂.

关 键 词：沙漠化 自然因素 人为因素 定量分析 陕北农牧交错带 

分 类 号：S181[农业科学—农业基础科学]