中心城市形成前南通市域城镇的形成与时空演变特征

南通地处长江三角洲北隅的沿江沿海交界处,位于我国一级开发轴线"T"型的顶点,与上海隔江相望。南通市域城镇形成和空间结构演变是伴随着陆地的不断长成而自西北向东南推进,城镇数量由无到有,城镇空间结构由简单到复杂,城镇规模由小到大,城镇联系由松散至紧密。历史时期城镇的形成与发展可分为三阶段:城镇空白阶段,城镇形成阶段,中心城市出现阶段等。南通市域城镇的最初形成与煮盐业、水运及海防等因素密切相关,故城镇多沿海岸线呈不规则的弧形分布,沿运河均匀分布。中心城市通州形成后,挣脱了对扬州和泰州的依赖,在行政上与其并列,城镇多沿通州城分布。

THE GROWTH AND TIME SPATIAL EVOLUTIONARY CHARACTERISTICS OF NANTONG URBAN SYSTEM BEFORE THE CENTRAL CITY COMES INTO BEING

Nantong is located in the north corner of the Yangtze River Delta where Yangtze River joins the Yellow Sea, Nantong is at the vertex of the T-shaped first-grade development axis of our country, facing Shanghai, the largest international trade center in China, across the Yangtze River. The evolution of Nantong urban system spatial structure is carrying forward along with the land growth from northwest to southeast, along with the towns' quantity growth from zero to many, along with the urban spatial structure growth from simple to complex, along with the towns' scale growth from small to large and along with urban connection growth from loose to close. Through researching, we draw the following conclusions: firstly, the development of Nantong urban system spatial structure is pushing with the land from northwest to southeast. Haian and Baipu towns are the oldest towns in Nantong areas; Secondly, Formation and development of Nantong city urban is affected by various factors, such as the land size, the change of coastline and bank line, the extension of sea walls and canals, the formation and development of central city and so on, but mans' activities are the most important factors except land size; Thirdly, In different periods, evolution of Nantong city urban spatial structure has different characteristics: in the historical period beginning, the old town spatial structure is simple, loose, small-scale urban; in the historical period evening, town spatial structure started to compact and form Tongzhou city as the center of the urban system; the recent town spatial structure comes dense, and scale vaster, grade clear, cities and towns tie closely.Fourth, Urban distributed in axis along the canal, coastline, sea walls and Yangtze River shoreline, etc. The transportation nodes developed into county town or central city. From the Wudai Shiguo Dynasty Tongzhou city came into being, to the Song Dynasty it became central city in the Nantong areas. Because of Tongzhou city had a good site and sea defense.