农户沼肥还田决策行为及其经济效应评价

Farm Household's Decision of Returning Biogas Residues to Farmland and Its Economic Effects

论文基于江苏省淮安市和连云港市沼气池使用户调查数据,运用Probit模型考察农户沼肥还田决策行为的影响因素,构建产出供给方程评价农户沼肥还田决策行为的经济效应。结果表明:沼气池使用天数越多、户主年龄越小、户主是村干部或农民专业合作社成员以及人均承包地越多的农户,越倾向于选择沼肥还田,而家庭总资产较少或较多的农户都不愿意选择沼肥还田。控制其他条件,农户沼肥还田可能性每增加1%,单位面积农地产值提高0.07%(10.81元/hm^2),若研究区域沼气池使用户全部选择沼肥还田,单位面积农地产值将提高356.55元/hm^2,具有一定的经济效应,倾向得分匹配方法(PSM)的稳健性分析进一步证实这一结论。目前中国沼肥还田率总体不高且没有规范的沼肥还田管理项目,进而提出鼓励沼气池使用户充分利用沼气池,提高农户沼肥还田积极性的政策建议。

Based on the survey data collected from 215 households using biogas digester in Huai＇an city and Lianyungang city in Jiangsu Province, this paper firstly analyzed the driving factors affecting farm households＇ decision of returning biogas residues（BGRs） to farmland with the Probit model, and then evaluated the economic effects of returning BGRs to farmland with the output supply function. Results indicated that younger householders, members of the village cadres or farmers＇ professional cooperatives, households with more contracted land per capita and households using biogas digester more frequently are more likely to return BGRs to farmland. While households with more or less fixed assets are reluctant to return BGRs to farmland. Returning BGRs to farmland can indeed increase crop output. Keeping other variables constant, 1% increase of the rate of returning BGRs to farmland may lead to 0.07% increase of crop output（around 10.81 yuan/hm^2）. In the research area, if all households using biogas digester can return BGRs to farmland, crop output will increase 356.55 yuan/hm^2,indicating considerable economic effects. Robustness test by PSM method further confirmed this conclusion. However, the rate of returning BGRs to farmland is quite low in China, and there is no specific management project regarding BGRs. Therefore, the government should encourage households using biogas digester to make full use of their biogas digesters and village cadres or members of farmers＇ professional cooperatives to play the leading role to allow farmers to truly understand the economic effects of returning BGRs to farmland and improve farmers＇ enthusiasm of returning BGRs to farmland.