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作 者:杜建丽[1] 林振山[1] 张真真[1] 刘会玉[1]
机构地区:[1]南京师范大学地理科学学院,江苏南京210046
出 处:《安徽农业科学》2008年第15期6143-6146,6150,共5页Journal of Anhui Agricultural Sciences
摘 要:用EMD方法首次对河北省的人口净增量与粮食净增量关系进行比较分析。结果表明:河北省人口净增量的波动周期为3.6、9.0和23.0年;粮食净增量的波动周期也为3.6、9.0和23.0年,两者的波动周期完全吻合。将其IMF分量进行对比,发现粮食净增量变化要滞后于人口净增量的变化。这一滞后性应引起注意,要加大科技投入,改变这种粮食产量的提高依赖于劳动力数量的趋势,要着眼于长远,制定符合社会经济发展和粮食安全问题的科学人口政策。The Empirical Mode Decomposition(EMD) method was used for the first time to make a comparative analysis on the correlation between the net increase of grain and that of the population in Hebei province. The result showed that the net increase of population and that of grain revealed the timescale fluctuations of about 3.6 year, 9.0 year and 23.0 year, and the cycles of them match quite well. The authors discovered that the increase of grain happened after the increase of population by making a comparative analysis on their IMFs. The government should paid more attention to this situation, They should adopt some steps, including increasing funds invested in technology, changing the trend that using to increased labor to enhance the grain output, and also setting down reasonable policy which according with the economy and grain safety in a long term.
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