宁夏粮食生产与耕地压力变化的分析与预测

本文基于最小人均耕地面积、耕地压力指数模型和时间序列平滑外推预测的方法对宁夏回族自治区自建国以来50多年进行粮食生产、耕地压力指数作动态变化分析,对未来15年的粮食生产、耕地变化、人口、耕地压力指数预测。结果表明:(1)粮食总产量大幅增加的趋势,1950年宁夏的粮食总产量为33512×104kg,人均占有量为266.05kg,到2004年粮食总产量为290488×104kg,是1950年粮食总产量的8.87倍。(2)耕地压力指数变化大致分为四个阶段。第一阶段,1950-1957年,耕地压力指数迅速减小,从1950年的1.46减少至1957年的1.16。第二阶段,1957-1961年,粮食产量急剧下降,耕地压力指数高达1.61,该区域的粮食处于严重不安全的状态。第三阶段,1962-1984年,耕地压力指数呈下降的趋势,到1984年降至最低点0.9,粮食安全处于富余状态。第四阶段,1984-2004年,处于波动有升的趋势。(3)1950-2004年,人均耕地面积和最小人均耕地面积一直处于减少的趋势,分别从1950年的0.57hm2和0.832hm2降至2004年的0.19hm2和0.22hm2。(4)在未来的15年里,宁夏的耕地压力指数有下降的趋势,人口继续的增加,到2020年可能达7435792人,粮食产量也将会提高,到2020年预计可达426663kg。区域粮食安全隐患较小,但耕地面积减少的趋势很严重,所以对耕地的保护需要进一步的加强。

Analysis and Prediction of Food Production and Cropland Pressure Changes in Ningxia

Based on the minimum cropland per capita,cropland pressure index model and the smooth extrapolation time series forecasting methods,the dynamic changes of food production,cropland pressure index from 1950 to 2004 in Ningxia Hui Autonomous Region were analyzed and predicted for next 15 years.The results showed that:(1) A substantial increase in grain output trends: Grain output was 33512 ×104kg in 1950,266.05 kg percapita;upto 2004 the total grain output was 290488×104kg,which was 8.87 times than in 1950.(2) The change of cropland pressure index roughly divided into four stages.In the first stage,cultivated land pressure index decreased rapidly,from 1.46 in 1950 decreased to 1.16 in 1956;In the second stage,for three years of natural disasters reason,a sharp decline in food production,land pressure index was as high as 1.61,the regional food was insecurity seriously from 1957 to 1961.The index of cropland pressure was downward trend from 1984 to 2004(the minimum to 0.9 in 1984).(3) Arable land area per capita and the smallest were in a declining trend from 1950 to 2004;(4) In the next 15 years,there was a downward trend about pressure index of cropland,the population continued to increase,it might reach to 7435792 in the 2020,grain output would also increase,being expected to reach 426663 kg by 2020.The trend of cropland declining was very serious,so the protection of cropland needed further strengthening.