应用生态学报2017，Vol.28Issue(3)：730-738,9.DOI:10.13287/j.1001-9332.201703.036
亚热带不同林分土壤矿质氮库及氮矿化速率的季节动态
Seasonal dynamics of soil mineral nitrogen pools and nitrogen mineralization rate in different forests in subtropical China
摘要
Abstract
We conducted an in situ incubation experiment to determine soil mineral N (NH4+-N and NO3--N) concentrations and soil net N mineralization rates (net ammonification rate and net nitrification rate) using close-top PVC tubes in three adjacent forests (natural forest,Castanopsis kawakamii and Cunninghamia lanceolata plantation) from September 2014 to August 2015 in subtropical China,investigating the effects of forest type and season on soil inorganic N concentrations and soil net N mineralization rates.Results showed that soil NO3--N was the dominant form in mineral N pool in all three forests,and the proportion of NO3--N to soil inorganic N content ranged from 55.1％ to 87.5％ and from 56.1％ to 79.1％ in natural forest and Cunninghamia lanceolata plantation,respectively.The effects of forest types on soil mineral N pool were only significant on soil NO3--N,and the concentration of NO3--N in Castanopsis kawakamii was significantly lower than in the other two forests.The NO3--N and mineral N pool varied seasonally in all forests,and were higher in dormant season (October to February) than in growing season (March to September).Soil nitrification rate was very low in the whole year in all three forests and soil net ammonification was the major process of soil net mineralization.Tree species significantly affected soil net ammonification rate,and the value under Chinese fir was significantly lower than the other two forests.The seasonal patterns of the soil net ammonification rate were not similar in all the three forests,but with the lowest value occurring in November and February in the following year.Analysis using variance of repeated measures indicated that soil mineral N concentrations and soil N mineralization rates were significantly affected by forest type and season,and correlation analysis showed that soil mineral N and soil N mineralization rate were significantly affected by water moisture and temperature,and the effects of litter on soil N mineralization rate were mainly through quality control,rather than the quantity control.关键词
森林类型/杉木/土壤有效氮/土壤氮转化速率/凋落物Key words
forest type/Chinese fir/soil available N/soil nitrogen transformation rate/litterfall引用本文复制引用
肖好燕,刘宝,余再鹏,万晓华,桑昌鹏,周富伟,黄志群..亚热带不同林分土壤矿质氮库及氮矿化速率的季节动态[J].应用生态学报,2017,28(3):730-738,9.基金项目
本文由国家自然科学基金项目(41371269)和国家重点基础研究发展计划项目(2014CB954003)资助 This work was supported by the National Natural Science Foundation of China (41371269) and the National Key Basic Research and Development Plan (2014CB954003). （41371269）
