农业小流域粮食产量稳定与水环境质量提高途径研究

实地调研了我国典型黑土区农业小流域粮食产量与施肥量的空间异质性,通过建立产量施肥量模型对施肥量进行空间上的优化调整,并选用SWAT(Soil and Water Assessment Tool)水文水环境模型进行流域水环境模拟.结果表明,施肥量在流域尺度上存在空间调整的可能和需要.在小流域粮食产量稳定目标下,通过施肥空间优化调整可减少小流域总施氮量的1.88%,同时SWAT模型模拟结果显示,施肥空间优化调整可降低NH 4+-N、NO 3--N营养盐输出分别为9.7%及5.6%.

Yield Stability Cooperated with Harmonious Water Environment Quality of Small Agricultural Watershed

This paper investigated the spatial variability of the correlations between grain yields and fertilization quantity within the selected agricultural watershed, in the typical black soil region, and then optimized the fertilization quantity at different landscape farmlands within the watershed based on the regression equations. Study simulated the surface runoff water quality before and after fertilization spatial adjustment with the achieved parameters by Soil and Water Assessment Tool (SWAT) model. The results showed that watershed scale fertilization adjustment is possible and necessary according to the spatial heterogeneity about fertilization and grain yields. Based on grain yield stability, spatial adjustment of fertilization reduced the whole watershed total N fertilization quantity by 1.88%, and the total non-point nutrients load reduction of NH4+ -N and NO3- -N was 9.7%, 5.6%, respectively.