论文部分内容阅读
可溶性有机氮(SON)是土壤氮状况的重要指标,然而,对森林土壤中SON的研究却少见报导。本项研究以具有典型高有机质和高有机氮特征的中国东北温带森林土壤为对象,通过早春冻融季节过后采样,得出土壤有机层水溶性SON含量为156.0–292.6mgkg-1,大致与文献报导的用盐溶液提取的SON量相当;而0–15cm矿质土层中水溶性SON含量为58.6–125.2mgkg-1,高于文献报导值3–10倍。土壤水溶性SON在不同林型和不同立地条件下差异很大。水溶性SON与土壤有机质含量和全氮量呈显著正相关,而与微生物氮量(MBN)呈负相关(未达统计学显著水平)。着重讨论了矿质土层SON含量过高以及SON-MBN负相关现象的成因。表4参33。
Soluble organic nitrogen (SON) is an important indicator of soil nitrogen status. However, the research on SON in forest soils is seldom reported. In this study, soil samples of temperate forests in northeastern China with typical characteristics of high organic matter and organic nitrogen were collected and sampled after the freeze-thaw season in early spring. The results showed that the water-soluble SON content of soil organic layer was 156.0-292.6mgkg-1, Reported that the amount of SON extracted with salt solution was comparable, while the water-soluble SON content in 0-15cm mineralized soil was 58.6-125.2mgkg-1, which was 3-10 times higher than that reported in the literature. Soil water-soluble SON vary widely in different forest types and different site conditions. There was a significant positive correlation between water-soluble SON and soil organic matter and total nitrogen, but negatively correlated with microbial nitrogen (MBN) (less than a statistically significant level). The causes of excessive SON content and negative correlation of SON-MBN in mineralized soil are discussed. Table 4 Reference 33.