Nitrogen in soils beneath 18 65 year old stands of subtropical evergreen broad-leaved forests in Laoshan Mountains in Eastern China

作     者：GU Feng ZHANG Kai ZHANG Yun-qi WANG Qin XU Xiao-niu 

作者机构：Department of Forest Science Anhui Agricultural University Hefei 230036 China 

出 版 物：《Journal of Forestry Research》 (林业研究（英文版）)

年 卷 期：2011年第22卷第4期

页      面：583-590页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 090301[农学-土壤学] 

基　　金：supported by National Natural Science Foundation of China (NSFC Nos. 30771719 and 30471386) 

主　　题：microbial biomass nitrogen nitrogen availability nitrogenmineralization soil horizon subtropical forest 

摘      要：Monitoring of soil nitrogen （N） cycling is useful to assess soil quality and to gauge the sustainability of management practices. We studied net N mineralization, nitrification, and soil N availability in the 0-10 cm and 11-30 cm soil horizons in east China during 2006-2007 using an in situ incubation method in four subtropical evergreen broad-leaved forest stands aged 18-, 36-, 48-, and 65-years. The properties of surface soil and forest floor varied between stand age classes. C：N ratios of surface soil and forest floor decreased, whereas soil total N and total organic C, available P, and soil microbial biomass N increased with stand age. The mineral N pool was small for the young stand and large for the older stands. NO3^--N was less than 30% in all stands. Net rates of N mineralization and nitrification were higher in old stands than jn younger stands, and higher in the 0-10 cm than in the 11-30 cm horizon. The differences were significant between old and young stands （p 〈 0.031） and between soil horizons （p 〈 0.005）. Relative nitrification was somewhat low in all forest stands and declined with stand age. N trans- formation seemed to be controlled by soil moisture, soil mierobial biomass N, and forest floor C：N ratio. Our results demonstrate that analyses of N cycling can provide insight into the effects of management disturbances on forest ecosystems.