Effects of mowing and nitrogen addition on soil respiration in three patches in an oldfield grassland in Inner Mongolia  

作　　者：Yi Han Zhe Zhang Changhui Wang Fenghe Jiang Jianyang Xia 

机构地区：[1]State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,Xiangshan,Beijing 100093,China [2]Graduate University of Chinese Academy of Sciences,Yuquanlu,Beijing 100049,China [3]Grassland Management Station of Duolun County,Duolun 027300,Inner Mongolia,China

出　　处：《Journal of Plant Ecology》2012年第2期219-228,共10页植物生态学报（英文版）

基　　金：National Basic Research Program(2007CB106803);National Natural Science Foundation of China(30925009).

摘　　要：Aims Vegetation type is important in determining variations in soil carbon(C)efflux under grassland managements.This study was conducted to examine the effects of mowing and nitrogen(N)addition on soil respiration and their dependences upon vegetation types in an oldfield grassland of northern China.Methods Soil respiration,temperature,moisture and aboveground net primary productivity(ANPP)and belowground net primary productivity(BNPP)were examined in response to mowing and N addition among the three patches dominated by different species(named as grass,forb and mixed patches,respectively)in the growing seasons(May–October)from 2006 to 2008.Important Findings Across the 3 years,soil respiration in the grass patch was greater than those in the forb and mixed patches,which could have been ascribed to the higher soil moisture(SM)in the grass patch.Mowing had no impact on soil respiration due to unaltered SM and plant growth.Soil respiration was stimulated by 6.53%under N addition,and the enhancement was statistically significant in 2006 but not in 2007 or 2008 because of the limited water availability in the later 2 years.There were no interactive effects between mowing and N addition on soil respiration.Soil respiration showed positive dependence upon SM,ANPP and BNPP across plots.The results suggest that soil water availability and plant growth could be the primary factors in controlling the temporal and spatial variations in soil respiration and its response to different treatments.Our observations indicate that grassland managements(i.e.mowing for hay once a year)may have little influence on soil respiration of the oldfield grassland in northern China.

关 键 词：MOWING nitrogen addition PATCH semiarid grassland soil C flux soil water availability 

分 类 号：S81[农业科学—畜牧学]