长期地膜覆盖及不同施肥处理对棕壤有机碳和全氮的影响

Effects of Long-term Mulching and Fertilizer Treatments on Organic Carbon and Total Nitrogen in Brown Soil

以长期地膜覆盖及不同施肥处理的棕壤为研究对象,全面地阐述了土壤有机碳和全氮的变化情况。研究结果表明:经过17年的耕作,无论是施有机肥还是有机肥与化肥配施均能显著增加土壤中有机碳的含量。覆膜栽培与裸地栽培比较,覆膜导致土壤有机碳消耗,有机碳含量降低。氮的变化情况:裸地各处理与有机碳的变化相似。氮肥处理(N4)覆膜土壤中全氮的含量比相应的裸地处理高;有机肥处理(M4)和有机肥与氮磷肥高量处理(M4N2P1)中,覆膜全氮的含量比相应的裸地低。无论是覆膜还是裸地,各施肥处理对土壤氮库的贡献大小依次为:有机无机配施>有机肥>单施化肥>对照。

A 17-years＇ follow-up monitoring program was accomplished on the brown earth in Shenyang Agricultural University. It was found that, no matter what kinds of fertilization, organic manure or com- bined application of organic manure and fertilizers both increase the concentration of organic carbon evidently. According to covered and uncovered treatments, the former treatments cause the decreasing of the concentration of organic carbon. The concentrations of total nitrogen in uncovered treatments were similar with organic carbon. The content of total nitrogen in covered treatments are lower than corresponding uncovered treatments, except N4 treatment. Contribution of different treatments to soil nitrogen pool is as follow：Organic manure or combined application of organic manure and fertilizers 〉 organic manure 〉 fertilizer 〉 contrast.