水淹时长与底质交互作用对鄱阳湖湿地植被格局形成的影响

The pattern formation of wetland vegetation distribution is restricted by wetland environmental conditions. It is very important that reveal the response mechanism of vegetation pattern to environmental change for wetland ecosystem protection and management. Many scholars have pay their attention to the influence of hydrological situation changes on the vegetation in Poyang Lake in recent years. However it can’t fully explain the complexity and variability of wetland vegetation distribution. The applicant have noticed that the change of substrate may be the important impact factor of the wetland vegetation differentiation under the same waterlogging condition. The project takes the wetland vegetation in different sediments of Poyang Lake as the research object. The heterogeneity of vegetation distribution under different sediments and the interaction between waterlogging duration and substrate on plant growth are studied by the methods of field investigation, control experiment, quantitative ecological analysis and so on. The purpose is to clarify the key impact factors in the pattern formation of wetland vegetation distribution in Poyang Lake, to reveal the dynamic changes and the internal mechanisms of “vegetation-substrate-hydrology”. Finally it can provide theoretical reference and countermeasure basis for the protection, management and sustainable development of Poyang Lake wetland.

湿地植被分布格局的形成受到湿地环境条件的制约，揭示植被格局对环境变化的响应机制对湿地生态系统保护与管理十分重要。水文情势对鄱阳湖湿地植被的影响近年来受到众多学者的关注，但仍无法全面解释其湿地植被分布的复杂性与多变性，申请人注意到底质变化可能是相同水淹条件下湿地植被分异的重要影响因子。本项目以鄱阳湖不同沉积相湿地植被为研究对象，采取野外调查和控制实验相结合的方法，运用数量生态分析等多种分析手段，重点研究不同湖泊沉积下植被分布的异质性规律；水淹时长和底质对植物生长的交互作用，以期阐明影响鄱阳湖湿地植被分布格局形成的关键因子，揭示鄱阳湖“植被-底质-水文”的动态变化特征和内在机制，为鄱阳湖湿地保护、管理及可持续利用提供理论参考和对策依据。

湿地植被分布格局的形成受到湿地环境条件的制约，研究表明水文情势对鄱阳湖湿地植被具有重要的影响，但仍无法全面解释湿地植被分布的复杂性与多变性。我们先前的研究表明，底质变化可能是相同水淹条件下湿地植被分异的重要影响因子。本项目以鄱阳湖不同土壤沉积类型优势湿地植物为研究对象，采取野外调查和控制实验相结合的方法，探讨了水淹时长和底质对植物生长的交互作用机制。我们的研究结果表明，鄱阳湖湿地植物群落分布与多样性受到表层土壤颗粒组成、水淹时长、高程等环境因子的共同影响，且在不同土壤沉积类型间，湿地植物群落分布呈现一定的规律性，群落多样性也存在一定的变化梯度；水淹时长与底质对湿地植物的生长具有显著的交互作用，底质质地差异能够影响湿地植物水淹下功能性状的响应规律，底质质地对湿地植物生物量积累的影响性质会随着水淹时长的变化而改变，水淹时长与底质交互作用对湿地植物生物量的积累具有显著的正面效应。研究结果有利于打开湿地植被分布与环境因子关系研究的新视角和湿地管理规划的新思路。