温带典型草地土壤净氮矿化作用研究

应用树脂芯方法,研究了内蒙古锡林河流域不同降水强度3种草地类型土壤净氮矿化作用.结果表明,7～10月份,羊草草原的平均净氮矿化率为0.333 kg·(hm²·d)^-1,贝加尔针茅草原为0.316 kg·(hm²·d)^-1,克氏针茅草原为0.211 kg·(hm²·d)^-1;在相同的培养周期内,分阶段培养和连续培养对土壤的净氮矿化量和净氮矿化速率有显著影响;降雨是影响该区域氮素矿化的主要因素之一,3种草地类型土壤水分变化量与土壤净氮矿化速率呈正相关关系,相关系数分别为0.80、0.61、0.56.

Soil Net Nitrogen Mineralization in the Typical Temperate Grassland

Soil net nitrogen mineralization rate of three types temperate grassland in Inner Mongolia, China was studied using the resin-core technique. The major results include: the net nitrogen mineralization rate of the Stipa baicalensis meadow grassland, the Aneulolepidum Chinense grassland and the Stipa krylovii grassland were 0.333 kg·(hm²·d)^-1, 0.316 kg·(hm²·d)^-1 and 0.211 kg·(hm²·d)^-1 respectively during the field incubation period of July to October,2005; Soil net nitrogen mineralization accumulation and rates was remarkably different between phase incubation and continuous incubation during the same field incubation period; Rainfall was one of the main factors affecting nitrogen mineralization. The net nitrogen mineralization rate was correlated with the change of soil moisture in all of the measured sites, the correlation coefficient was 0.80, 0.61 and 0.56.