Intergenerational Behavioral Transmission, Neighborhood Effects, and Farmers’ Farmland Quality Protection Behavior: A Case Study of Fertilizer Application in Gansu, China

Farmers’ decision-making behavior is shaped by familial intergenerational ties and neighborhood relations, yet research often treats them as independent decision-makers, overlooking these critical dynamics. This oversight can undermine the effectiveness of policies on farmland quality. Using micro-survey data from 1045 maize farmers in Gansu Province, China, this study explores farmers’ fertilizer reduction behavior through a theoretical framework that incorporates intergenerational behavioral transmission and neighborhood effects. Economically optimal fertilizer usage was calculated using the Cobb–Douglas production function, with hierarchical regression models and instrumental variable methods employed for analysis. Our findings reveal the following: (1) The Cobb–Douglas production function indicates that 74.1% of farmers apply more fertilizer than the economically optimal amount. (2) Effective intergenerational behavioral transmission and positive neighborhood effects significantly promote farmers’ adoption of reduced fertilizer application practices, with neighborhood effects further enhancing the effects of intergenerational behavioral transmission. (3) Stronger neighborhood effects not only enhance the positive impact of effective intergenerational behavioral transmission but also mitigate the negative impact of ineffective transmission. Additionally, neighborhood effects mediate the relationship between intergenerational behavioral transmission and fertilizer reduction. This study highlights the importance of kinship and neighborhood dynamics in shaping farmers’ fertilizer use and provides insights for designing more effective farmland quality protection policies. By acknowledging these relational factors, governments can better promote sustainable agricultural practices and minimize excessive fertilizer application.