循环型农业清洁流域建设——以柘皋河流域为例

为在流域尺度下构建全面系统的面源污染防控体系,以安徽省巢湖流域内一个典型的农业流域柘皋河流域作为案例,调查该流域种植制度、养殖模式、农村生活等数据,分析其面源污染特征,基于水环境容量计算柘皋河流域种植源氮磷减排潜力,在借鉴生态清洁小流域建设思路的基础上,提出循环型农业清洁流域建设,并从环境效益和技术应用两方面构建评价体...

Construction of circular agricultural clean watershed: A case study of Zhegaohe watershed

Aiming at establishing a system highlighting prevention and control measures on reducing NPS pollution at watershed scale, a typical agricultural watershed in Chaohu region, Zhegaohe watershed, was chosen as study object. Detailed survey was conducted to investigate the farming system, breeding mode and rural living. By learning from the thought of eco-clean small watershed construction, the definition and evaluation goals of circular agricultural clean watershed were put forward. Comprehensive assessment system of circular agricultural clean watershed was constructed. A primary evaluation on the implementation of pollution reduction measures was conducted. The results showed that: The annual N and P discharge load in the watershed were 1 923 and 128 t, respectively. Based on the water environmental capacity, the discharge load reduction percentages of NPS pollutants were calculated. It was found that 37% for nitrogen and there was abundant water environment capacity for phosphorus. Through implementing clean combined-technologies, the N and P discharge load reduction amount were calculated, which can achieve the corresponding reduction goals for Zhegaohe watershed. Based on the implementation effects, a preliminary assessment was conducted and the results showed that the sum of 7 weighted indicators was 0. 684 indicating that the management performance was disappointed to some extent and thus the effects of combined-technologies was correspondingly limited. Finally, policy suggestions, e. g. marketing mechanism, strengthening farmland infrastructure construction, optimization of spatial distribution pattern for planting and breeding industries and increasing policy support were put forward to achieve higher clean technology efficiency and improve the watershed environmental management drasticly.