科尔沁沙地水资源投入对粮食生产的影响定量研究——以奈曼旗为例  

Quantitative Analysis on the Impact of Water Resource on Crop Production in Horqin Sandy Land—A Case Study in Naiman Banner

作　　者：葛小东[1] 胡苏军[1] 叶青[1] 

机构地区：[1]华中农业大学资源与环境学院,武汉430070

出　　处：《自然资源学报》2012年第9期1471-1479,共9页Journal of Natural Resources

基　　金：国家自然科学基金项目(40801235)

摘　　要：借鉴Cobb-Douglas全要素生产函数,以粮食总产量为因变量,以包括年降水量等气候要素、耕地面积等经济要素和化肥施用量等技术要素在内的10项投入为自变量,构建1987年至2008年期间奈曼旗农业生产投入产出模型。结果表明:①影响奈曼旗粮食总产量的关键因素为农业劳动力(t=9.44,P=0.00)、年降水量(t=8.33,P=0.00)和灌溉用水量(t=6.89,P=0.00)。除农业劳动力外,其他两项因子均与水资源有关;年降水量和灌溉用水量的弹性系数均大于1,说明粮食总产量的增长倍数高于水资源投入的增长倍数,水资源的继续投入将导致粮食产出快速增长。②根据模型,农业劳动力、灌溉用水量、年降水量的回归系数分别为5.13、1.55和1.46,显示当地劳动力投入及水资源投入均存在不足,单独增加某个投入要素即会导致粮食产出以更快速度增长;随着奈曼旗农业劳动力不断减少,且年降水量波动性增强且呈下降趋势,粗放式的灌溉明显加强。根据模型,其他投入要素不变、农业劳动力减少1%时,灌溉用水量增加3.31%;其他投入要素不变、年降水量减少1%时,灌溉用水量增加0.94%。③降水的波动会导致粮食单产量的波动,而灌溉用水量在很大程度上影响了粮食单产量水平(R2=0.543);降水量的减少导致农民通过扩大播种面积来获得增产,因此降水量的年际变化和播种面积的年际变化之间呈现明显的反向变动关系。总体来讲,奈曼旗农业生产对灌溉用水的依赖程度不断加大。随着灌溉用水的持续投入,其增产作用将逐渐降低,并且对当地脆弱生态系统带来进一步的压力。A model was built up based on the Cobb-Douglas Function. The impact of three kinds of variables, included climate factors, economic factors and technological factors, on the crop production during the period from 1987 to 2008 was quantitatively analyzed. The results showed that ： 1 ） The labor （ t = 9.44, P = 0.00 ）, the irrigation water （ t = 6.89, P = 0.00） and the precipitation （ t = 8.33, P = 0.00） were the most important factors to the crop production, when be- ing compared to other 7 factors. The irrigation water and the precipitation were related to the water resource, reflecting that water resource accelerated the crop production. 2） Actually, the labor kept declining since 2003, leading to the serious waste of water resource. According to the re- gressed model, the irrigation water increased by 3.31% when the labor declined by 1%. And al- so, the irrigation water increased by 0.94% when the annual precipitation declined by 1%. 3 ） The fluctuation of the annual precipitation affected the yield per unit area greatly. The change of the annual precipitation was negatively related to the change of the area of the arable land, since local residents frequently enlarged their arable land when the weather got drier. The irrigation water also impacted the yield per unit area greatly. In a word, the water resource played much more important role in the crop production, and the water consumption brought heavier bur- den on local ecosystem.

关 键 词：奈曼旗 水资源 生产函数 

分 类 号：F326.11[经济管理—产业经济] F323.213F224