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机构地区:[1]河南农业大学信息与管理科学学院,河南郑州450002 [2]中国农业大学经济管理学院,北京100083
出 处:《干旱地区农业研究》2012年第4期242-247,共6页Agricultural Research in the Arid Areas
基 金:河南省自然科学基金(2011A790013);2010年度河南省政府决策研究课题(B244)
摘 要:依据河南省粮食单产的数据,把1978—2009年粮食单产的变化划分为4个阶段,系统分析了河南省粮食单产的阶段性、趋势性和稳定性特征。结果表明:粮食单产整体上呈上升趋势,但年际波动较大;增加的年份占绝对优势;离散系数随时间变化在逐渐缩小,且时间间隔长的阶段的离散度要高于时间间隔短的阶段。利用灰色系统理论,对影响河南省粮食单产变化的因素进行了关联分析,结果表明:在1978—2009年整个时期中,与河南省粮食单产的关联程度大小依次是有效灌溉面积、农业机械总动力、化肥施用量、农村用电量。但在不同的阶段,农业生产条件指标对粮食单产有不同的影响程度。Based on the data of grain yield per hectare in Henan Province,the change of grain yield per hectare from 1978—2009 was divided into four stages.The change trend and characteristics of grain yield per hectare was systematically analyzed from 3 viewpoints of period,trend and stability.The result showed that the grain yield per hectare presented a rising trend on the whole and the variance between years was very large,the increasing years were the dominant,discrete coefficient decreased with time,and the long time interval stage's discrete coefficient was greater than the short time interval stage's.The impact factors of grain yield per hectare were analyzed using grey system theory.The results showed that the related degree was in the order of irrigated area,total agricultural machinery power,consumption of chemical fertilizer,electricity consumed in rural areas,which also illustrated the change of agricultural production conditions' effect at different stages.
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