乌梁素海湖滨湿地不同植物群落生态系统光合/呼吸动态研究

Study on Ecosystem Photosynthesis and Respiration Dynamics of Different Plant Community along the Lakeshore of Ulansuhai Lake

湖滨湿地是湿地生态系统重要的类型之一,其独特的水文条件形成了具有典型成带分布的湿地植物群落,开展不同植物群落间的CO_(2)排放特征研究,对厘清湖滨带植物群落生态系统碳源/汇功能的调控作用具有重要意义。为研究湖泊湖滨湿地生态系统不同植物群落下光合/呼吸动态特征及其影响因素,在乌梁素海湖滨湿地选择4种典型植物群落进行生态系统净CO_(2)交换(Net ecosystem CO_(2)exchange,NEE)、生态系统呼吸(Ecosystem respiration,ER)和生态系统总初级生产力(Gross primary production,GPP)监测。结果表明:在生长季乌梁素海湖滨带不同植物群落间NEE、ER和GPP具有明显的日变化和季节变化特征,且不同植物群落间存在显著差异。淹水植物芦苇和藨草群落光合速率大于非淹水植物碱蓬和白刺群落,且两种淹水植物群落对生态系统CO_(2)汇贡献较高。湖滨带不同植物群落光合/呼吸速率受光照强度和温度影响显著,表明光照和温度调控了湖滨带湿地植物群落光合/呼吸速率。本研究厘清了乌梁素海湖滨湿地不同植物群落下光合/呼吸动态特征及固碳潜力,为退化湖滨湿地的恢复重建提供理论依据。

Lakeshore wetland is one of the important types of wetland ecosystem,and its unique hydrological conditions form the typical wetland plant communities with belt distribution.Carrying out the study of CO2 emission characteristics among different plant communities is of great significance to clarify the regulatory role of plant community ecosystems on carbon source/sink function in the lakeshore wetland.In order to study the dynamic characteristics of ecosystem photosynthesis and respiration of different plant communities along the lakeshore wetland of Ulansuhai Lake and their influencing factors,4 typical plant communities were taken for monitoring the net ecosystem CO2 exchange(NEE),ecosystem respiration(ER)and gross primary production(GPP).The results showed that NEE,ER and GPP have obvious diurnal and seasonal changes and significant differences among different plant communities during the growing season.The photosynthetic rate of submerged plant communities of P.australis and S.triqueter was higher than that of the nonflooded communities of S.glauca and N.roborowskii,and both submerged plant communities significantly contribute to the COz sink of the ecosystem.The photosynthesis and respiration rate of different plant communities were significantly affected by light intensity and temperature,indicating that light and temperature were the dominant factors regulating photosynthesis and respiration of the wetland plant communities in the lakeshore.This study clarified the photosynthetic/respiration dynamic characteristics and carbon sequestration potential of different plant communities along the lakeshore wetland of Ulansuhai Lake,and provided a theoretical basis for the restoration and reconstruction of the degraded lakeshore wetland.