洞庭湖的景观动态分析

景观元素分为三种：嵌块体、走廊、本底，在洞庭湖区，湖泊是洞庭湖的本底，洲滩是一种典型的嵌块体，在湖区分布广泛，数量众多，是现在洞庭湖区最为活跃的景观元素之一，研究湖泊的演变规律，洲滩的结构，动态变化，以及洲滩对洞庭湖功能的影响，对洞庭湖的治理有着重要参考价值，整个湖区洲滩面积呈增长趋势，从1961年到1985年面积增长了815km^2，由于人工因素和自然因素的差异，洲滩分布在不同湖区县市，不同时期，不同高程出现了不同规律：洲滩主要分布在岳阳、沅江和汉寿三地，不同类型洲滩的演化动态在不同湖区分布呈现异质性，洲滩（景观结构）的改变导致洞庭湖功能（调蓄功能，生态功能等）的退化，因而沿庭湖洲滩治理刻不容缓，此外，还论述了芦苇，人工林和洲滩演化的相互影响，论证了芦苇是洲滩扩张的一个重要因素，而人工林有利于开发和治理洲滩。

DYNAMICAL ANALYSIS OF LANDSCAPE OF DONGTING LAKE

There are three radical elements of landscape: patch, corridor, background. In Dongting Lake area,the lake is the background, bottomland is a typical patch,and widespread,and huge in number. Buttomland is the most active landscape element in Dongting Lake area. Studying the evolving pattern of Dongting Lake and bottomland structure, dynamics and influence to Dongting Lake's function is very important to harness of Dongting Lake. Because of the change of environment,bottomland in different regions of Dongting Lake,at different period,at different altitude presents diffent distribution patterns.The area of bottomland increase 815 km\+2 from 1961 to 1985.The Botomland disseminates mainly in Yueyang,Yuanjiang,Hanshou county,with obvious heterogeneity in bottomland altitude in different lake regions. The bottomland altitude of West Dongting Lake is the highest,while that of East Dongting Lake the lowest.The change of bottomland area (landscape structure) leads to the degradation of landscape function (store floodwater, ecology function). So we have to consider the importance to control bottomland. Moreover, in this paper, the interactions among reeds, artificial forest, and bottomland revolution are discussed, and that the reed is an important factor of bottomland extension,and artificial forest is available for the exploitation and bottomland control are pointed out.