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机构地区:[1]中国农业科学院,北京100081 [2]中国农业科学院农业环境与可持续发展研究所,北京100081 [3]农业部种植业司,北京100125
出 处:《中国农学通报》2008年第8期504-509,共6页Chinese Agricultural Science Bulletin
摘 要:【研究目的】准确掌握建国以来中国小麦生产的总体变动趋势,为产业结构的继续优化和调整提供参考。【方法】利用计算历年全国小麦种植面积、产量重心的方法和全国28个省(市,自治区)1949—2005年的资料,分析建国以来全国小麦种植重心、总产量重心以及单产重心的移动轨迹、偏移距离等。【结果】总体上,20世纪70年代以前小麦生产重心向北、东方向偏移比较明显,70年代以后逐渐回移并趋于平稳,说明东西部、南北方的差距经历了先加大后缩小的变化过程。通过对比分析发现,小麦单产重心偏移变化比较剧烈,总偏移距离最大,种植面积的总偏移距离最小,总产量重心的总偏移距离介于两者之间。【结论】建国以来小麦生产重心偏移总体上从剧烈走向平稳,南北方种植面积扩张速度基本平衡,西部扩张速度大于东部。[OBJECTIVE] The objective is to support a reference to realize the variation trend and optimize and adjust industry structure.[METHOD]The gravity centre coordinate of wheat plant area and yield every year were calculated by 28 provinces in China.The track and variation distances of wheat production gravity centre were analyzed and contrasted.[RESULTS]The results displayed that the wheat production gravity centre moved to north and east before 1970’s and moved back after that in general.It indicated that the difference between the northern and southern,eastern and western increased firstly and decreased later.The variation of wheat yield per unit gravity centre was very acute,and its excursion distance was the most,while the excursion distance of wheat plant area was the least.[CONCLUSION]The excursion distance of wheat production gravity centre of China became little and little,it indicated that the expending speed of wheat plant area in south and north was in balance,but it was quicker in west than in the east.
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