基于农业生态地带模型的中国粮食产能动态评估

Dynamic Assessment of the Grain Productivity in China Based on the Enhanced Agricultural Ecological Zoning( AEZ) Model

随着人口增加和人们生活水平的不断提高,我国粮食消费需求将继续呈刚性增长,使得粮食品种和区域结构性矛盾加剧,而粮食产能的动态评估能够让我们加深认识我国粮食供需平衡,对制定适宜于我国经济社会发展同时保障粮食安全的粮食可持续发展战略具有重要意义。论文选取农田生产力作为我国粮食产能的指标,通过改进农业生态地带(AEZ)模型,动态嵌入不同县域水平的管理和投入水平的限制性因子,集成县级截面数据估计投入系数权重,并基于此估算了全国2000-2010年间农田生产力水平。研究发现,2000年以来,我国农田生产力虽年际间存在波动,但总体呈现增长的态势,且区域差异性显著。农田生产力水平存在从沿海到内陆、从南向北及从东向西的递减的梯度,而局部地区农田生产力变化明显,表现出明显的东西分异规律,其次是南北分异规律。而对各个地区农田生产力平均值统计发现,东部沿海地区与南部省份的农田生产力要高于内陆省份,西部地区农田生产力普遍低于东部和中部地区。2000、2005、2010年全国分县统计的粮食产量数据与动态估算结果进行精度验证,其相关系数分别达到0.82、0.76和0.89,实际产量为估算结果的69.4%、73.4%、67.2%,较好的反映了我国农田生产力的基本状况。最后,基于我国农田生产力时空变化规律和局部差异性特征,以及我国经济区水平上的中国农田生产力的变化规律,从耕地数量保障、农业管理和投入水平提高以及适宜的农业区划方面,提出适宜于我国自然环境状况和社会经济发展的农田生产力保障策略,对保障我国的农田生产力的稳定增长方面的规划决策与政策制定具有参考价值。

With increasing population and improving living standards,grain consumption demand in China will continue to grow rigidly,consequently intensify the regional structural contradictions of grain supply.Scientifically dynamic assessment for grain productivity would be able to acquire a good understanding of the present situation of China＇ s grain production capacity,which is important to make the strategy suitable for the development of economy development and food security.Aiming at estimating the grain productivity under different local management strategies and input levers,this paper enhanced the core model of AEZ,set up transaction function between potential grain productivity and grain productivity.The result of dynamic assessment of the nationwide grain production during 2000-2010 shows,since 2000,although there exists annual fluctuation of the agricultural land productivity,the national average level of grain production experienced a slight increase,with the obvious regional difference.There is a decreasing gradient of grain productivity from the coastal areas to inland,from south to North and from east to west,with obvious change within regions,represented an east to west territorial differentiation,and then the south to north.In the light of regional agricultural productivity analysis,the grain productivity in the eastern coastal region and the southern provinces are higher than inland provinces,while the west regions is lower than the middle and east regions.Compared with the county lever grain production statistics data in 2000,2005 and 2010,the correlation coefficient is 0.82,0.76 and 0.89,respectively,and the realistic grain production accounts for 69.4％,73.4％ and 67.2％ of the simulated value,which could be a well reflection of the agricultural land productivity.At last,based on the characteristics of the temporal and spatial variation and local differences in China＇ s grain productivity,as well as eight economic zones in China,grain production security strategies,that in terms of agricultural land protection,agricultural management and input lever improvement,as well as suitable agricultural zoning planing,are proposed to maintain the natural environment and regional social and economic development at the same time,which might provide some references for planning and policy-making to ensure a steady growth of grain productivity.