芦苇和互花米草功能性状对长江口盐沼湿地碳交换通量的影响OA

Coastal wetlands,recognized as vital blue carbon ecosystems,exhibit carbon sequestration functions that are strongly associated with plant functional traits.This study investigated the regulatory mechanisms of functional traits on carbon sequestration in the Yangtze River Estuary using two dominant salt marsh species:Phragmites australis and Spartina alternifllora.We quantified key functional traits,including morphological traits,photosynthetic parameters,and chlorophyll concentration,while simultaneously measuring ecosystem carbon fluxes(CO2 and CH4 emissions).Results demonstrate significant interspecific differences in functional traits:S.alternifllora exhibited superior leaf area index(LAI),chlorophyll concentration,photosynthetic efficiency,and CO2 assimilation capacity compared with P.australis.The photosynthetic capacity of P.australis was predominantly regulated by LAI,whereas that of S.alterniflora was mainly regulated by chlorophyll concentration.The CO2 fluxes showed a strong positive correlation with leaf traits and photosynthetic parameters.In contrast,CH4 emissions showed no association with leaf traits;however,they were influenced by morphological traits,such as aboveground biomass,plant height and plant density.These findings highlight that plant functional traits differentially mediate carbon sequestration pathways and greenhouse gas dynamics in coastal wetlands,providing critical insights for vegetation-based blue carbon management strategies.