Effect of nitrogen and phosphorus addition on leaf nutrient concentrations and nutrient resorption efficiency of two dominant alpine grass species  

作　　者：LIU Yalan LI Lei LI Xiangyi YUE Zewei LIU Bo 

机构地区：[1]State Key Laboratory of Desert and Oasis Ecology,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China [2]Cele National Station of Observation and Research for Desert Grassland Ecosystems,Cele 848300,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Shandong Provincial Key Laboratory of Soil Conservation and Environmental Protection,College of Resources and Environment,Linyi University,Linyi 276000,China

出　　处：《Journal of Arid Land》2021年第10期1041-1053,共13页干旱区科学（英文版）

基　　金：This research was supported by the National Natural Science Foundation of China(41807335);the Shandong Provincial Natural Science Foundation,China(ZR2020MC040);the National Key Technology Research and Development Program of China(2019YFC0507602-2);the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020434);the National Postdoctoral Program for Innovative Talents(BX201700279).

摘　　要：Nitrogen(N)and phosphorus(P)are two essential nutrients that determine plant growth and many nutrient cycling processes.Increasing N and P deposition is an important driver of ecosystem changes.However,in contrast to numerous studies about the impacts of nutrient addition on forests and temperate grasslands,how plant foliar stoichiometry and nutrient resorption respond to N and P addition in alpine grasslands is poorly understood.Therefore,we conducted an N and P addition experiment(involving control,N addition,P addition,and N+P addition)in an alpine grassland on Kunlun Mountains(Xinjiang Uygur Autonomous Region,China)in 2016 and 2017 to investigate the changes in leaf nutrient concentrations(i.e.,leaf N,Leaf P,and leaf N:P ratio)and nutrient resorption efficiency of Seriphidium rhodanthum and Stipa capillata,which are dominant species in this grassland.Results showed that N addition has significant effects on soil inorganic N(NO_(3)^(-)-N and NH_(4)^(+)-N)and leaf N of both species in the study periods.Compared with green leaves,leaf nutrient concentrations and nutrient resorption efficiency in senesced leaves of S.rhodanthum was more sensitive to N addition,whereas N addition influenced leaf N and leaf N:P ratio in green and senesced leaves of S.capillata.N addition did not influence N resorption efficiency of the two species.P addition and N+P addition significantly improved leaf P and had a negative effect on P resorption efficiency of the two species in the study period.These influences on plants can be explained by increasing P availability.The present results illustrated that the two species are more sensitive to P addition than N addition,which implies that P is the major limiting factor in the studied alpine grassland ecosystem.In addition,an interactive effect of N+P addition was only discernable with respect to soil availability,but did not affect plants.Therefore,exploring how nutrient characteristics and resorption response to N and P addition in the alpine grassland is important to understand nutri

关 键 词：leaf nutrient concentration nutrient resorption efficiency leaf N:P ratio N addition P addition Seriphidium rhodanthum Stipa capillata 

分 类 号：S812[农业科学—草业科学]