运用江苏省52个县(市)2004-2006年的相关社会经济数据,从区域层面对测土配方施肥项目实施的环境和经济效果进行实证研究。结合测土配方施肥项目分批次、分年度试点推广的特征,基于DID理论模型有机耦合EKC分解模型、C-D模型和供给反应函数模型,估计实施测土配方施肥项目对单位耕地面积化肥施用量和种植业总产值的影响以及效果的持续性。研究表明:控制其他因素,测土配方施肥项目的实施显著提高了样本县(市)的种植业总产值,而且效果逐年递增,但是其对化肥施用量(施用强度)的削减效果从项目实施第2年才开始显现;EKC假说验证发现,单位耕地面积化肥投入与经济发展存在“倒U型”关系,拐点为人均GDP 16 615元。据此提出了积极推广测土配方施肥技术、实现环境与经济“双赢”的建议。
Based on socio-economic data from 52 counties (cities) in Jiangsu province from 2004 to 2006, this paper empirically assesses the regional environmental and economic effects of formula fertilization by soil testing project applying DID model with the combination of EKC model, C-D model and output-supply model. Due to the gradual and yearly pilot-based promotion of this project, DID model was applied to examine the effects of the implementation of this project on the use of chemical fertilizer per unit farmland and GDP of arable sector as well as the sustainability of these effects. The result shows that by controlling other factors, implementation of the project of formula fertilization by soil testing could significantly increase the GDP of arable sector,and the effect increases year by year. While its reduction effect on the use of chemical fertilizer per unit farmland only appears in the second year after the implementation of this project. Results also show that fertilizer application intensity has an inverted U-shaped relationship with both economic development and a turning point of GDP 16 615 yuan per capita. Consequently, this paper proposes suggestions on how to actively promote formula fertilization by soil testing technology so that environmental and economic win-win development could be achieved