不同施肥处理对黑土中各形态氮素含量动态变化的影响

The Effect of Different Fertilization Treatments on Content Change of Different form Nitrogen in Black Soil

以黑土为研究对象,通过盆栽试验系统研究了化肥及其配施玉米秸秆处理土壤不同形态氮素含量的动态变化趋势及其释放特性。结果表明:无机氮肥施入土壤后经过各种转化作用主要以有机氮的形式存在于土壤中,高量氮肥的施用增加了土壤有机氮和微生物体氮的含量,与单施化肥处理相比,化肥配施玉米秸秆处理也增加了土壤中有机氮和微生物体氮的含量。与土壤有机氮含量相比,土壤无机氮含量较低,高量氮肥处理无机氮含量高于低量氮肥处理,与单施化肥相比,化肥配施玉米秸秆降低了土壤无机氮的累积量,说明高量氮肥的施用会增加无机氮肥的残留,而化肥与有机物料配合施用能够促进无机氮肥向土壤有机氮的转化,从而避免无机氮大量积累而造成氮素损失。

A pot experiment with spring wheat and black soil was conducted to study the dynamic changes and release characteristics of different form nitrogen in soil at different fertilization treatments. The results showed that organic nitrogen was the main form at crops growth season after chemical N fertilizer was applied and transformed through different approaches. The application of high N fertilizer increased the amount of soil organic N and microbial biomass nitrogen; compared with single application of chemical fertilizer, combination of chemical fertilizer and maize straw also increased the amount of soil organic N and microbial biomass nitrogen. Compared with the content of soil organic N, the content of soil inorganic N was very low, and the content of soil inorganic N in N2 and N2＋maize straw treatments were higher than those of N 1 and Nl＋maize straw treatments. Compared with single application of chemical fertilizer, combination of chemical fertilizer and maize straw reduced the accumulative amounts of soil inorganic N, indicating that application of high chemical N fertilizer increased its residual in soil inorganic N pool, combination application of chemical fertilizer and organic materials could enhance transformation of inorganic N to soil organic N, consequently avoided N losses due to the abundant accumulation of inorganic N in soil.