温州湾湿地互花米草地下芽功能性状及其影响因素

Underground Bud Functional Traits and their Influencing Factors of Spartina alterniflora in Wenzhou Bay Wetland

地下芽是外来入侵植物互花米草种群扩散的基础,研究其功能性状及其与环境的关系可为掌握互花米草入侵机制提供理论依据。本研究以3处温州湾滨海湿地互花米草为研究对象,开展其地下芽功能性状和环境调控研究。结果表明:1)地下芽形态性状及生物量均表现为乐清湾>鳌江口>瓯江口,且根茎芽密度、芽长度与直径比在不同地区间存在显著差异(P>0.05)。2)乐清湾与鳌江口湿地地下芽全氮含量及氮磷比较高且两地差异不显著,而瓯江口湿地则显著低于其它两地(P<0.05)。3)土壤含水率是互花米草地下芽形态性状及生物量(解释度为17.8%)、化学计量(解释度为27.4%)的主控因子。维护和控制湿地水环境是沿海地区大范围防治互花米草扩散的有效途径。

Underground bud of invasive plant Spartina alterniflora is the basis for its population expansion,functional traits of the species and their relationship with the environment provide a theoretical basis for understanding the invasion mechanism of the species.The functional traits of underground bud and regulation of environment of S.alterniflora were studied at three coastal wetlands in Wenzhou Bay.The results showed that:1)The morphological traits and biomass of underground buds followed the order of Yueqing Bay>Aojiang Estuary>Oujiang Estuary,and there were significant differences in rhizome bud density,bud length and diameter ratio among different regions(P>0.05).2)There was no significant difference in total nitrogen content and nitrogen-phosphorus ratio of underground bud between Yueqing Bay and Aojiang Estuary,significantly higher than those in Oujiang Estuary(P<0.05).3)Soil moisture was the main factor controlling morphological traits and biomass(Contribution rate 17.8%)and stoichiometry(Contribution rate 27.4%)of S.alterniflora.Maintaining and controlling the wetland water environment is an effective way to prevent the large scale invasion of S.alterniflora in coastal areas.