摘要
为阐明色季拉山山地酸性棕壤土壤氮素含量、无机氮分配特征及对植被类型的响应,以色季拉山海拔3900～4 100 m的区域为研究对象,研究不同植被条件下土壤0～10 cm和10～20 cm层次土壤总氮、无机态氮(铵态氮、硝态氮)含量。结果表明:(1)土壤全氮、硝态氮和铵态氮含量空间变异较大,且均表现为0～10 cm>10～20 cm。在95%置信区间0～10 cm和10～20 cm土层中全氮含量分别为3.14～4.24 g·kg-1和2.03～3.37g·kg-1,硝态氮分别为119.96～169.95 mg·kg-1和85.86～124.69 mg·kg-1,铵态氮分别为404.36～513.26 mg·kg-1和276.32～369.41 mg·kg-1,土壤铵态氮含量显著高于硝态氮。(2)土壤无机氮占总氮的比例较高,0～10 cm和10～20 cm层次上95%置信区间分别为:15.41～20.45%和16.01～23.79%。(3)植被类型对土壤氮素含量和形态影响显著;(4)乔木冷杉对土壤氮的表聚作用较明显,其表层土壤氮素含量显著高于其它植被。研究结果建议,对于色季拉山土壤氮素分布特征研究除海拔梯度和植被类型因素外,还应充分考虑土壤类型对氮素空间异质性的影响。
Soil nitrogen is an important environment and nutrient element, but few studies were focused on the nitrogen spatial variation and responding to different vegetation in Sejila mountain, Tibet. In order to elucidate the variation of mountain acid brown soil nitrogen content and response to vegetation, the soil total nitrogen （TN） and the mineral nitrogen （Nmin） （ included nitrate N （NN） and ammonium nitrogen （AN）） were analyzed at the altitude range of 3 900-4 100 m of Sejila mountain. The results show （1） The spatial variability of soil TN, NN and AN content were obvious, and that in 0-10 cm layer was higher than that in the 10-20 cm layer; （2） A higher value of Nmin/TN, 95% confidence intervals were 15.41-20.45% and 16.01-23.79% respectively of 0-10 cm and 10-20 cm; （3） The vegetation type significantly influenced soil nitrogen content and nitrogen forms; （4） The fir significant increased nitrogen content of the surface soil and was higher than other vegetation. The results suggested that it is should considered that the effects of soil type to nitrogen spatial heterogeneity besides altitudinal gradient and vegetation.
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2013年第10期126-129,140,共5页
Journal of Central South University of Forestry & Technology
基金
国家自然科学基金(41161052)
西藏自治区自然科学基金项目
西藏农牧学院青年科学基金项目
关键词
山地酸性棕壤
色季拉山
西藏
植被
全氮
硝态氮
铵态氮
mountain acid brown soil
Sejila mountain
Tibet
vegetation
total nitrogen
nitrate nitrogen
ammonium nitrogen
