农户生计视角下我国粮食生产重心北移机理与管控途径研究

The gravity of grain production in China has been turning northward recently. As livelihood diversification is growing notable, a thorough study on how China's grain production responses and adapts to living transition thus means great significance to the optimization of food production patterns and the realization of sustainable rural development. Based on the academic viewpoint that macroscopic grain production patterns are the result of microscopic farmers' behavior response to external shocks, this project evaluates the spatial patterns of both rural livelihood diversification and grain production dissimilation, analyzes the internal components, external factors and core indicators of grain production system, calculates the contribution of livelihoods transition to grain production's shifting to northern region, explores the relationship between crops choice, agricultural inputs, and livelihood assets and its geographical backgrounds, analyzes the response mechanism of how the food production gravity turns northward under livelihood transition by scale transformation, and finally finds out the optimization plan of national crops patterns and countermeasure for food production in each areas binding response mechanism, scenario simulation and state assessments. Integrated methods of GIS, sampling survey, and quantitative models are applied. The project not only stresses the regional difference and comprehensive characteristics of grain production, but also pays great attention to the convergence of micro peasant behavior and macro optimization of grain production patterns. Therefore, it helps innovating the theory and methods of grain production patterns of which the existing research focus on macro- regression analysis, deepens understanding the evolution of regional man-land relationship, and provides a scientific base for China's grain production decisions.

我国粮食生产重心近年来持续北移。从农户生计视角分析粮食生产地域分异机制及其管控途径，对于顺应生计转型规律优化粮食生产格局具有重要意义。本项目立足外部冲击经由微观农户行为响应进而决定宏观粮食生产格局这一学术观点，综合应用GIS、典型调查、多学科理论和数学模型，揭示农户生计转型与粮食生产的演替格局，研究粮食生产系统的内在构成要素、外部环境因素与核心表征指标，测算农户生计转型对粮食重心北移的贡献程度，探寻农户作物选择、农业要素投入与农户生计资产及其地理背景的相关关系，经由尺度转换提炼粮食生产重心北移机理，结合情景模拟与状态评估，提出中国粮食生产格局的优化方案与不同类型区粮食生产的管控途径。项目突出粮食生产的综合性和区域差异性，实现微观农户行为决策与宏观粮食生产格局的有机衔接，是对既有研究侧重宏观回归分析的一种发展，可加深对区域人地关系演变过程的理解，为国家粮食生产决策提供科学依据。

我国粮食生产重心持续北移，引发生态环境代价巨大、北方粮食增产潜力有限等方面的担忧。粮食生产格局调整受气候变化、市场波动等宏观因素影响，这些因素最终会落实到农户层面并经由农户适应行为产生影响。从农户生计视角分析粮食生产地域分异机制及其管控途径，对于顺应生计转型规律优化粮食生产格局具有重要意义。本项目综合应用GIS、实地调研和模型方法，从农户生计视角研究了粮食生产格局的变化特征、影响机理与调控途径。主要结果如下：1）分析了农户的粮食经营行为决策机理，指出农户是理性的行为主体，在耕地的多重用途之间进行最优配置，由此影响粮食种植规模与投入强度。2）1990~2016年我国粮食生产重心沿“先西南后东北”的顺序向北偏东方向移动了201 km，人口重心沿“先西南后东北”的顺序向南偏东移动了21km，粮食重心与人口重心的距离扩大了近3倍，加剧“北增南减、北粮南运”的粮食产销格局。3）全国粮食产量呈现波动性增长趋势。省域粮食生产进一步向粮食主产省集中，东北和西部增幅尤为明显。县域Global Moran's I值由1990年的0.6510增加到2015年的0.723，显著高高集聚类型区、显著低低集聚类型区变化较大。4）典型村庄农户从事非农就业的比例趋于上升，非粮化播种比例趋于下降。劳动力投入仍是维持粮食生产的重要因素，大规模非农就业给全国尤其是东中部地区粮食生产带来了不利影响；相比净利润，现金收益更影响农户种粮决策。受资源禀赋、非农就业、种植结构、基础设施等因素影响，各区域粮食生产格局变化机制存在一定差异。农业生产经营制度及其主体变迁对粮食产量和农业全要素生产率均表现出显著的正向影响，且呈现较高的同步性。5）估算了中国种植业产值增长来源，探索了粮食适度经营规模的确定标准，并从资源价格、农业生产结构、科技进步等方面探索了应对措施。课题资助发表论文21篇，其中SCI/SSCI/EI论文4篇。出版著作1部。提交咨询报告2份，其中1份获得省部级领导批示。作为参评依据之一，获评国土资源科学技术奖二等奖1项。