Soil Net Nitrogen Mineralization in an Aneulolepidium Chinensis Grassland, Inner Mongolia
内蒙古羊草草原土壤净氮矿化研究

Nitrogen mineralization is one of the most important processes in the nitrogen cycling. The soil net nitrogen mineralization in an Aneulolepidium Chinensis grassland was studied using the resin-core technique from July 20 to August 26, 2004. Influences caused by different length of incubation intervals and the experimental disturbance to soil nitrogen transformation processes were also discussed in the paper. The Aneulolepidium Chinensis grassland locates in the Xilin River Basin of Inner Mongolia, China. The results showed that the accumulated amount of net nitrogen mineralization was 4.44 KgN.ha-1 during the study period; average daily rate was 0.12 KgN.ha-1.d-1. The length of incubation intervals brings significant impact on net N mineralization measurement. After 37 day continued incubation, the amount of net nitrogen mineralization was 14.07 KgN.ha-1; the measurement was influenced greatly by the root decomposition. The net N mineraliazation rate correlated with soil moisture (R=0.67, P=0.22). Resin-core incubation technique causes little disturbance to the grassland soil and is a good method to study the net N mineralization of the temperate grassland in field.