东洞庭湖洪水前后典型湿地植物化学计量特征动态变化  

The dynamics of C,N,P stoichiometry of dominant wetland plant in the East Dongting Lake before and after flood

作　　者：曾静[1] 侯志勇[1] 李旭[1] 耿明明 谢永宏[1] ZENG Jing;HOU Zhi-yong;LI Xu;GENG Ming-ming;XIE Yong-hong(Dongting Lake Station for Wetland Ecosystem Observation and Research,Key Laboratory for Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China)

机构地区：[1]中国科学院亚热带农业生态研究所、中国科学院亚热带农业生态过程重点实验室、洞庭湖湿地生态系统观测研究站,湖南长沙410125

出　　处：《环境生态学》2024年第2期65-70,共6页Environmental Ecology

基　　金：国家科技基础资源调查专项(2021FY100704,2019FY100602);湖南省-基金委区域创新联合基金重点项目(U21A2009);自然资源要素耦合过程与效应重点实验室开放课题(2022KFKTC015)资助。

摘　　要：洪水对湿地土壤-植被系统养分循环有重要影响。本研究以东洞庭湖湿地典型植物短尖苔草(Carex brevicuspis)和南荻(Triarrhena lutarioriparia)为研究对象,于2018年洪水期前后(5月、10月)测定短尖苔草和南荻生长特征、生态化学计量特征及土壤理化性质,并对化学计量学特征与环境特征的相关性进行了分析。结果表明:南荻植株的生物量和密度洪水前显著高于洪水后,短尖苔草生物量和密度洪水前后都没有显著差异;短尖苔草、南荻叶片有机碳(SOC)洪水后显著高于洪水前;短尖苔草叶片全氮(TN)洪水前显著低于洪水后;南荻叶片TN、全磷(TP)洪水前显著高于洪水后;短尖苔草叶片TP洪水前后没有显著差异。短尖苔草叶片C∶N、C∶P、N∶P洪水前后均无显著差异,南荻叶片C∶N、C∶P洪水前显著低于洪水后,但N∶P洪水前后无显著差异。东洞庭湖短尖苔草、南荻叶片N∶P<14,东洞庭湖短尖苔草、南荻生长更多的受N限制,洪水前后都与土壤N、P含量无显著相关性。本研究结果对阐明洪水对湿地植物化学计量特征的影响有重要意义。Flood plays an important part in soil-plant nutrient cycling in wetland.C,N,P stoichiometry are critical indicators of biogeochemical coupling in ecosystems.To clarify the dynamic characteristics in leaf SOC,TN,TP,the stoichiometric ratio and the driving factors of dominant plant Carex brevicuspis,Triarrhena lutarioriparia in East Dongting Lake wetland and explore the status of the wetland nutrient utiliazation and restrict,we took the dominant plant Carex brevicuspis and Triarrhena lutarioriparia in East Dongting Lake wetland as study objects.This study measured the C,N,P concentrations,density as well as aboveground plant biomass before flood and after flood in 2018.Besides,we analyzed the seasonal dynamics of TC,TN and TP in relation to the biomass of Carex brevicuspis plant and the physical and chemical characteristics of soil.The results indicated that the biomass and density of Triarrhena lutarioriparia in pre-flooding period were significantly higher than that of the post-flooding period,while no significant difference was detected for biomass and density of Carex brevicuspis before and after the flooding period.During post-flooding period,the contents of organic carbon for Carex brevicuspis and the Triarrhena lutarioriparia leaves was significantly higher than that of the pre-flooding period.The TN of Carex brevicuspis in pre-flooding period was significantly lower than that of the post-flooding period,while the contents of TN and TP for Triarrhena lutarioriparia leaves in pre-flooding period were significantly higher than that of the post-flooding period.The content of TP in Carex brevicuspis leaves displayed no difference before and after the flooding period.C∶N,C∶P,and N∶P of Carex brevicuspis leaves showed no significant difference before and after the flooding period,while C∶N and C∶P of Triarrhena lutarioriparia leaves were significantly lower in pre-flooding period than that of the post-flooding period,but the N∶P was not significant different before and after the flooding period.The gr

关 键 词：东洞庭湖 湿地 化学计量学 营养元素限制 

分 类 号：X8[环境科学与工程—环境工程]