水位梯度变化对鄱阳湖洲滩湿地生态水文过程的影响机制

The quickly increase and withdraw of water level in Poyang Lake had formed unique characteristics of multiple types of wetland vegetation habitats and ecosystems. In recent years, the lake level abnormal movements lead to the degenerative succession process among wetlands vegetation. Poyang Lake wetlands vegetation have a strong sensitivity to the changes in water level gradient. Water gradient for groundwater level and submerged water level are important environmental gradient in controlling the water transfer process in the beach wetland of Poyang Lake. Based on the clue for water level gradient- water transfer process in the interface - ecological response for plant,this project aims to use a comprehensive method, such as positioning monitoring, control experiments, numerical simulation and isotopic tracer study, to reveal the transmission, interception and transformation process in the groundwater - soil - plant - atmosphere system. The interaction between surface water,soil water and groundwater will be investigated in the beach wetland under the condition of alterlative dry and wet process. The project is also expected to study the response regulation of plant to water level gradient. Furthermore, a coupled eco-hydrology model is wished to be established. The eco-hydrological model is developed to reveal the process of water tranfer process in groundwater - soil - plant - atmosphere system under the alternative wet and dry conditions and quantitative evaluation of environmental effects is conducted based on the different hydrologic process in the Poyang Lake wetland.The study results provide a scientific basis for awareness and understanding of the hydrological mechanism of seasonal wetland in Poyang Lake. It also provided a reference to the theories and methods for eco-hydrology.

鄱阳湖快速的涨退水过程，形成了独特的多类型湿地植被生境与生态系统特征。近年来，湖泊水位的异常变动导致湿地植被出现了退化性的演替过程。鄱阳湖湿地植被对水位梯度的变化具有很强的敏感性。因此，本项目以"水位梯度变化－界面水分过程传输-植被生态特征响应"为研究主线，运用定位监测、控制实验、数值模拟与同位素示踪等多种研究方法与手段，以期能系统揭示水分在地下水-土壤－植被－大气界面中的传输、截留和转化过程，定量辨析干湿交替变化条件下鄱阳湖洲滩湿地地表水、土壤水、地下水的交互作用机制；研究典型洲滩湿地植被对水位梯度变化的响应特征；建立基于过程和机理的洲滩湿地生态水文耦合模型，阐明水位变化对鄱阳湖典型洲滩湿地植被空间格局变化的影响。研究结果可进一步深入理解和认识鄱阳湖湿地生态过程变化中的水文机理，丰富与发展通江湖泊湿地生态水文学的理论与方法，为鄱阳湖的植被恢复与重建提供理论依据和技术支持。

鄱阳湖快速的涨退水过程，形成了独特的多类型湿地植被生境与生态系统特征。近年来，湖泊水位的异常变动导致湿地植被出现了退化性的演替过程。鄱阳湖湿地植被对水位梯度的变化具有很强的敏感性。因此，本项目以“水位梯度变化－界面水分过程传输–植被生态特征响应”为研究主线，运用定位监测、控制实验、数值模拟与同位素示踪等多种研究方法与手段，以期能系统揭示水分在地下水-土壤－植被－大气界面中的传输、截留和转化过程，定量辨析干湿交替变化条件下鄱阳湖洲滩湿地地表水、土壤水、地下水的交互作用机制；研究典型湿地植被对水位梯度变化的响应特征；建立基于过程和机理的洲滩湿地生态水文耦合模型，阐明水位变化对鄱阳湖典型洲滩湿地植被空间格局和演替的影响。研究结果可进一步深入理解和认识鄱阳湖湿地生态过程变化中的水文机理，丰富与发展通江湖泊湿地生态水文学的理论与方法，为鄱阳湖的植被恢复与重建提供理论依据和技术支持。