温度和土壤类型对氮素矿化的影响

采用短期(15 d)室内好气培养方法,研究我因东部三类主要旱地土壤(黑土、潮土和红壤)有机氮矿化对温度(15～30°C)的响应及其影响因素.结果表明,土壤累积净矿化氮量的顺序为黑土>潮土>红壤,其中高有机质土壤大于低有机质土壤.黑土累积净矿化氮量随温度升高而增加,但潮土和红壤在25℃以上表现出持平和下降趋势.土壤矿质氮...

Effects of temperature and soil type on nitrogen mineralization

Variation between soils in the response to temperature of nitrogen (N) mineralization was investigated in laboratory incubations. Three types of soils with different soil organic matter contents including black soil (Phaeozem), chao soil (Cambisol) and red soil (Acrisol) were sampled from farmlands of different regional climates of east China. The soils were incubated at 15, 20, 25 and 30oC and constant moisture conditions and the accumulation of soil extractable NO3-N and NH4-N was followed for 15 days. First-order rate equation was fitted to data to estimate net mineralization rate constants (k0) and the size of the mineralizable part of native soil N (N0). The accumulated N mineralization increased by the sequence of Red soilBlack soil>Chao soil for 15–20oC and a sequence of Black soil> Red soil>Chao soil for 20–30oC. Soil net N mineralization was significantly affected by soil organic matter and total N, and rate constant (k0) by soil C/N ratio.