THE Study Of Variation About River Environment And Temporal-Spatial Distribution Of The Ancient Cities In Zhejiang Province:A Case Study From Ming Dynasty,Qing Dynasty To The Republic Of China

Water is the key,even the soul,of the development about cities,where the water changes will determine the development of the cities.Even more,with the coastal water environment variation,it also affects the spatial and temporal distribution of cities.This paper explores the relationship between variation of water environment,including water system variation and estuarine seawall expansion,and cities' temporal-spatial distribution in ancient Zhejiang province in Ming Dynasty,Qing Dynasty to the Republic of China,which is analyzed by looking up literatures and researching field,and using Arc GIS10.2 software to vectorize history maps;In-order to study the dependence of river in difference periods at different scales,including 1 000 m,2 000 m,3 000m,and 4 000 m buffers.At the end of the paper,this paper analyzes the expansion of cities with developing of land and building seawalls at river estuary using overlay analysis by GIS.The result shows that:1.River formations divided the spatial patterns of the cities in the ancient different periods.Specially,cities in Qiantang River Basin were much more and more mature than others;Variation of rivers,lakes and waterways would determine cities' fate,which might change cities spatial patterns more or less;Density of cities in different historical periods were different with time going.But in spatial,the coastal basins were more higher.2.In the Yongjiang Basin,Feiyun River Basin,Aojiang Basin,the dependence of cities on the water system increased from Ming Dynasty to 1947,while the Tiaoxi Basin decreased.However,Jiaojiang Basin and Qiantang River Basin were relatively stable,but the dependence in the single flow to sea basin and the inter-provincial basin was non-dependent.3.The spatial distributions of majority cities in Canal Basin and Aojiang Basin concentrate in the range of 2 000 m,and the majority cities in Qiantang River Basin,Oujiang Basin,Tiaoxi Basin and Feiyun River Basin were located in the range of 3 000 m,what's more,Qiantang River Basin,Oujiang Basin's cities concentrated in 1 000 m-2 000 m,and cities in Oujiang Basin concentrated in 1 000 m-3 000 m.While cities in the single flow to sea basin,which located in the coastal area along the coastline 2 000 m,and the inter-provincial basin were far away from the river.4.From Ming and Qing Dynasties to the Republic of China,comparing the North and the South in Zhejiang province,the expansion of the river estuary plains in the northern was more intense,especially in the south bank of the Qiantang River,which played an important foundation for the northward movement of the towns in the Ningshao plain,The expansion in the Oujiang estuary plain was also evident,which was very vital on the expansion of cities and rural settlements.