比较收益、财政支农对耕地“非粮化”的影响——基于动态空间杜宾模型和门槛效应模型

在种粮经济收益和粮食战略功能矛盾冲突下，分析种粮比较收益和财政支农对耕地“非粮化”的影响，对提出“非粮化”治理策略、稳定国内粮食供给安全具有重要意义。本文基于2009—2021年全国面板数据，运用动态空间杜宾模型和面板门槛回归模型进行分析，发现：1)2009—2021年我国耕地“非粮化”具有明显的空间分异特征，呈现“高-高、低-低”聚集区两极分布；2)种粮比较收益能够抑制耕地“非粮化”，且具有空间溢出效应；3)财政支农对耕地“非粮化”的抑制作用具有双重门槛特征，呈现“先增加后减少”的趋势。对此，建议建立产销区省际横向利益补偿机制，在“生产端”保障种粮主体利益；结合区域种粮比较收益，合理调整农业种植结构；完善财政支农资金监管制度，促进种粮利益补偿机制建设。

The impacts of the comparative returns and the financial support to agriculture on the “non-grain” of farmland: based on the dynamic spatial Durbin model and the threshold effect model

Under the conflict between economic returns from grain cultivation and strategic grain functions, it is essential to analyze the impacts of the comparative returns from grain cultivation and the financial support to agriculture on the “non-grain” of farmland in order to put forward strategies for the management of “non-grain” and stabilize the security of domestic grain supply. Based on the national panel data from 2009 to 2021, this paper adopts the dynamic spatial Durbin model and the panel threshold regression model to analyze the situation. Results show that: 1) from 2009 to 2021, China’s “non-grain” farmland has prominent spatial differentiation characteristics, showing a “high-high, low-low” aggregation area bipolar distribution; 2) the comparative income from grain cultivation can inhibit “non-grain” farmland , and has a spatial spillover effect; 3) the inhibition of financial support for agriculture on the “non-grain” farmland has a double threshold characteristics, showing a trend of “first increase and then decrease”. Therefore, to promote the construction of compensation mechanism for the interests of grain, this paper recommends to establish an inter-provincial horizontal interest compensation mechanism in the production and marketing areas, to protect the interests of the main body of grain in the “production end”; to integrate the regional grain comparative income and the reasonable adjustment of the agricultural planting structure; and to improve the supervision system of financial support for agriculture.