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机构地区:[1]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]西北农林科技大学林学院,陕西杨凌712100
出 处:《干旱地区农业研究》2015年第3期217-223,237,共8页Agricultural Research in the Arid Areas
基 金:中国科学院科技服务网络计划(STS)项目(KFJ-EW-STS005);中国科学院科技基础性工作专项(2014FZ10100)
摘 要:为了明确西北地区耕地生产力及其动态演变过程,掌握该区在全国粮食生产中的整体水平,利用1982—2012年西北地区耕地生产力数据,结合GIS分析描述了该区近30年耕地生产力和耕地压力指数动态演变过程,及该区在全国粮食生产中的整体水平,结果表明:近30年来,西北地区耕地生产力呈现出小范围波动、连续上涨的发展趋势,从1982年的2078.28kg.hm-2上升至2012年的5643.75 kg.hm-2,翻了近3番,但其年均增长率不稳定,年际间变化幅度相对较大,在1996年到达历史最高水平23%;西北地区耕地生产力在全国的比重明显上升(由1982年的0.455上升到2012年的0.749),但又始终低于全国平均水平(耕地粮食生产力指数始终小于1),随着时间的推移,该区粮食生产中心主要向粮食生产能力较高的新疆和陕西地区集中;西北地区耕地压力指数在阶段性波动变化中呈现出略微减小趋势,耕地压力有所缓解,但其缓解幅度并不大,耕地压力级别始终处在Ⅱ级预警值(0.91~1.10)范围内。In order to evaluate the dynamic evolution of cultivated land productivity in Northwest China and assess the overall level of grain production in the country ,productivity data in cultivated land of Northwest China during 1982—2012 were analyzed using GIS software .The results showed that cultivated land productivity in northwest area displayed a fluctuating but constantly increasing tendency in a small scale ,resulting a three times increase from 2078 .28 kg·hm-2 in 1982 to 5643 .75 kg·hm-2 in 2012 .However ,the average annual growth rate was not stable and the inter-annual varia-tion remained large ,reaching a historically high value of 23% in 1996 .The cultivated land capacity in northwest area became increased significantly (from 0 .455in 1982 to 0 .749 in 2012) ,which ,however ,had always been lower than the national average level (relative index of cultivated land productivity was always less than 1 ) .With time going ,grain pro-duction centers in the area moved mainly to Xinjiang and Shaanxi that have higher grain production capacity .The pres-sure index of cultivated land in northwest region showed periodical fluctuations with a slightly decreasing trend ,relieving cultivated land pressure to a mild level .The pressure level of cultivated land had always been at warning level II in a cer-tain range (0 .91~1 .10 ) .
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