Response of Nitrogen Leaching to Nitrogen Deposition in Disturbed and Mature Forests of Southern China  

作　　者：FANG Yun-Ting M. YOH MO Jiang-Ming P. GUNDERSEN ZHOU Guo-Yi 

机构地区：[1]Dinghushan Forest Ecosystem Research Station, South China Botanical Garden, the Chinese Academy of Sciences, Zhaoqing, Guangdong 520670 （China） [2]Tokyo University of Agriculture and Technology, Tokyo 183-8509 （Japan） [3]Forest ＆ Landscape Denmark, Faculty of Life Sciences, University of Copenhagen, Hoersholm Kongevej 112970 （Denmark）

出　　处：《Pedosphere》2009年第1期111-120,共10页土壤圈（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.30670392);the Knowledge InnovationProgram of the Chinese Academy of Sciences (Nos.KZCX2-YW-432-2 and KSCX2-SW-133).

摘　　要：Current nitrogen (N) leaching losses and their responses to monthly N additions were investigated under a disturbed pine (Pinus massoniana) forest and a mature monsoon broadleaf forest in southern China. N leaching losses from both disturbed and mature forests were quite high (14.6 and 29.2 kg N ha-1 year-1, respectively), accounting for 57% and 80% of their corresponding atmospheric N inputs. N leaching losses were substantially increased following the first 1.5 years of N applications in both forests. The average increases induced by the addition of 50 and 100 kg N ha-1 year-1 were 36.5 and 24.9 kg N ha-1 year-1, respectively, in the mature forest, accounting for 73.0% and 24.9% of the annual amount of N added, and 14.2 and 16.8 kg N ha-1 year-1 in the disturbed forest, accounting for 28.4% and 16.8% of the added N. Great N leaching and a fast N leaching response to N additions in the mature forest might result from long-term N accumulation and high ambient N deposition load (greater than 30 kg N ha-1 year-1 over the past 15 years), whereas in the disturbed forest, it might result from the human disturbance and high ambient N deposition load. These results suggest that both disturbed and mature forests in the study region may be sensitive to increasing N deposition.Current nitrogen （N） leaching losses and their responses to monthly N additions were investigated under a disturbed pine （Pinus massoniana） forest and a mature monsoon broadleaf forest in southern China. N leaching losses from both disturbed and mature forests were quite high （14.6 and 29.2 kg N ha^-1 year^-1, respectively）, accounting for 57% and 80% of their corresponding atmospheric N inputs. N leaching losses were substantially increased following the first 1.5 years of N applications in both forests. The average increases induced by the addition of 50 and 100 kg N ha^-1 year^-1 were 36.5 and 24.9 kg N ha^-1 year^-1, respectively, in the mature forest, accounting for 73.0% and 24.9% of the annual amount of N added, and 14.2 and 16.8 kg N ha^-1 year^-1 in the disturbed forest, accounting for 28.4% and 16.8% of the added N. Great N leaching and a fast N leaching response to N additions in the mature forest might result from long-term N accumulation and high ambient N deposition load （greater than 30 kg N ha^-1 year^-1 over the past 15 years）, whereas in the disturbed forest, it might result from the human disturbance and high ambient N deposition load. These results suggest that both disturbed and mature forests in the study region may be sensitive to increasing N deposition.

关 键 词：atmospheric N deposition N addition N leaching loss N saturation subtropical forests 

分 类 号：S15[农业科学—土壤学]