生态学报2024，Vol.44Issue(5)：2069-2080,12.DOI:10.20103/j.stxb.202304170785
黄土丘陵区氮磷添加对草地群落优势种养分利用特征的影响
Effects of nitrogen and phosphorus addition on nutrient use characteristics of grassland community dominant species in loess hilly-gully region
摘要
Abstract
In order to elucidate the effects of nitrogen(N)and phosphorus(P)addition on nutrient utilization characteristics of grassland dominant species and explore the changes mechanism of grassland community structure and species diversity in loess hilly-gully region,five typical dominant species of common grassland communities including Bothriochloa ischaemum,Stipa bungeana,Lespedeza davurica,Artemisia sacrorum,and Artemisia scoparia,were selected as research objects.A split-plot N and P addition experiment was conducted,with N addition as the main-plot and P addition as the subplot[main-plot:0(N0),25(N25),50(N50),and 100(N100)kg N hm-2 a-1;subplot:0(P0),20(P20),40(P40),and 80(P80)kg P2O5 hm-2 a-1].The leaf N and P ratio,N use efficiency,P use efficiency,N reabsorption efficiency,P reabsorption efficiency,relative biomass and their relations of the five dominant species were investigated.Results showed that the reabsorption efficiency of N and P was positively correlated,and their response to N and P addition amount was coupled in each dominant species.Under different N and P additions,L.davurica had the highest leaf N and P ratio,but possessed the lowest N reabsorption efficiency and P reabsorption efficiency.Under different N and P additions,B.ischaemum and S.bungeana had higher N reabsorption efficiency,P reabsorption efficiency,N use efficiency and P use efficiency than other species.Under P addition alone and combined with N25,the relative biomass of each dominant species was positively correlated with leaf N and P ratio and P use efficiency,while negatively correlated with N use efficiency,N reabsorption efficiency and P reabsorption efficiency.The relative biomass of each dominant species showed positive relationships with N reabsorption efficiency,P reabsorption efficiency,N use efficiency and P use efficiency,while showed negative relationships with N and P ratio under N addition alone or N50 and N100 combined with P addition treatments.Under unfertilized condition,B.ischaemum and S.bungeana had the highest relative biomass.Under low N and high P conditions,L.davurica had the highest relative biomass,while A.sacrorum and A.scoparia had the highest relative biomass under high N and high P conditions.Different dominant species showed different physioecological processes in responses to N and/or P addition,which determined their dominance in the grassland community,and this is the key mechanism for the change of grassland community structure and species diversity after N and P addition.关键词
氮磷添加/草地群落/养分重吸收效率/群落结构Key words
nitrogen and phosphorus addition/grassland community/nutrient resorption efficiency/community structure引用本文复制引用
牟英坤,陈志飞,周俊杰,赖帅彬,靳媛,王绍妍,徐炳成..黄土丘陵区氮磷添加对草地群落优势种养分利用特征的影响[J].生态学报,2024,44(5):2069-2080,12.基金项目
国家自然科学基金青年项目(42207531) （42207531）
国家"十三五"重点研发计划项目(2016YFC0501703) （2016YFC0501703）
