宋代长江沿线的水系变迁:基于主要河道与湖泊的考察

Changes of the River System along the Yangtze River in Song Dynasty:Researches on Major Watercourses and Lakes

在自然环境和人文社会因素综合作用下,宋代长江沿线的水系发生变迁。长江沿线的水系变迁着重反映在河道与湖泊两方面。在河道层面,主要表现在川江、荆江、城陵矶-湖口、湖口-扬州、扬子江等主干段线河床、岸线、河面、水量的变化上,其中以城陵矶至扬州波动最为明显,岸线频动,矶头较多,且出现了一些新的沙洲。在湖泊层面,则集中体现在太湖、鄱阳湖、洞庭湖等重要湖泊水体深度、湖面广度的改变上,太湖水网不畅面积渐趋缩小,鄱阳湖基本上奠定了今天的形态,洞庭湖不断向西拓展且持续沉降为历史时期水体最深的阶段。如是,运用环境史学的相关研究方法考察宋代长江沿线主要河道与湖泊的发展状貌,不仅可以了解当时长江沿线水环境的发展状况,还有助于为该地区的经济开发与水环境保护提供宝贵的历史经验。

In Song Dynasty,the water system along the Yangtze River changed under the influence of natural environment and human and social factors.The changes mostly happened in watercourses and lakes.Changes of watercourses were mainly reflected in the changes of the riverbeds,shorelines,water surface and water volume along the major rivers,and the most obvious changes happened between Chenglingji and Yangzhou,where the shorelines changed frequently,and there emerged more rocky outcrops and new sandbars.Changes in lakes were mainly reflected in the changes of the depth and breadth of water of major lakes like Taihu Lake,Poyang Lake and Dongting Lake.Taihu Lake gradually shrank due to blocked water networks.Poyang Lake basically came to be what it is today.Dongting Lake kept expanding westward and sinking into its deepest point in history.Therefore,the study of the evolution of major rivers and lakes along the Yangtze River in Song Dynasty with research approaches relevant to environmental history can not only reveals changes of the river system at that time,but also provides useful experience for the development of Yangtze River Economic Circle and water protection in China.