Phosphorus limitation on photosynthesis of two dominant understory species in a lowland tropical forest

作     者：Feifei Zhu Xiankai Lu Jiangming Mo 

作者机构：Key Laboratory of Vegetation Restoration and Management of Degraded EcosystemsSouth China Botanical GardenChinese Academy of SciencesXingke RoadTianheGuangzhou 510650China Graduate University of the Chinese Academy of SciencesYuquan RoadShijingshanBeijing 100049China 

出 版 物：《Journal of Plant Ecology》 (植物生态学报（英文版）)

年 卷 期：2014年第7卷第6期

页      面：526-534页

核心收录：

学科分类：090101[农学-作物栽培学与耕作学] 09[农学] 0901[农学-作物学] 

基　　金：National Natural Science Foundation of China(41273143) National Key Basic Research 973 Program(2010CB833502) Knowledge Innovation Program of the Chinese Academy of Sciences(KSCX2-EW-J-28) 

主　　题：N saturation P limitation photosynthesis lowland tropical forests southern China 

摘      要：Aims Elevated nitrogen(N)deposition in tropical regions may accelerate ecosystem phosphorus(P)***,it is not explicitly addressed that how changes in soil N and P availability affect foliar nutrients and photosynthesis of plants in tropical *** this study,we examined the effects of N and P additions on foliar nutrients and net photosynthesis of two dominant understory species,Randia can-thioides(***)and Cryptocarya concinna(***)in an N-saturated old-growth tropical forest(400-year-old)in south-ern *** A full factorial NP addition experiment(2×2)was established in 2007 and continued through August *** treatments,including control,N addition(150 kg N ha^(−1) year^(−1)),P addi-tion(150 kg P ha^(−1) year^(−1))and NP addition(150 kg N ha^(−1) year^(−1) plus 150 kg P ha^(−1) year^(−1))were set up in this *** traits maximum photosynthetic CO_(2) assimilation(Amax),stomatal conductance(gs),leaf transpiration(E),light satu-rating point,concentrations of chlorophyll a/b and foliar nutri-ents(N and P)of the two species were measured with standard *** Findings Three years of N addition had no significant effects on any measured photosynthetic parameter of either ***,N addition significantly elevated foliar N and P concentrations of one species(***),resulting in lower photosynthetic nitrogen use effi-ciency(PNUE).N treatments decreased foliar P concentration of the other(***),resulting in increased photosynthetic phos-phorus use efficiency,which was potentially related to N-induced P *** contrast,positive effects of P treatments on gs of ***-thioides,Amax and chlorophyll a+b of *** were observed.P treatments also elevated foliar P and PNUE of both species,imply-ing P induced more efficient use of *** results suggested a more important role of P than N on influencing photosynthetic traits of these two understory *** of P shorta