汉水流域核心-边缘结构的演变

流域空间结构研究是空间结构理论研究的深化，是基于具体区域类型的空间结构理论研究的尝试。可以说，流域空间结构的研究开辟了区域空间结构研究新的分支方向，是空间结构理论研究的一次发展和推动。文章以历史为主线，从中心城市的变迁、人口密度和城镇密度的变化来探讨汉水流域核心边缘结构的演变过程：先秦两汉时期，南阳盆地是汉水流域的核心区（南阳是汉水流域的政治经济中心和最大的城市），下游地区为边缘区；到唐宋时期，襄宜平原取而代之（襄樊成为全流域最重要的中心城市）；明代后期，汉口崛起，并很快发展成为包括汉水流域在内的长江中游地区乃至更大范围内的中心城市，因而下游地区理当为流域核心区，这时南阳退为边缘区。同时也指出影响流域结构演变因素主要为自然和技术因素、区位条件、历史背景、生产力的发展和社会的进步等因素。

Evolution of Core-Periphery Structure of Hanshui Valley

Valley spatial structure study is further development of spatial structure theories based on concrete region type.That is,research of valley spatial structure pioneers a new branch of region spatial structure,and promotes its development especially on its theoretical research.Based on the historical data, this paper discusses its evolution process of "core-periphery" structure with changes of population density and urban density as indexes in Hanshui valley: during Donghan dynasty and Xihan dynasty,Nanyang basin is a core region of Hanshui valley(Nanyang is the centre of politics and economics and the largest city among them);during Tangsong dynasties,Xiangyang plain has become a core region in place of Nanyang(Xiangfang become the major core city);during late of Ming dynasty,Hankou become quickly a core city not only in Hanshui valley but in Changjiang middle reaches region or more extensive region.Thus,the lower reaches of Hanshui has become a core region while Nanyang has degenerated a periphery region.And then points out that influential factors of valley structure evolution are natural factor and technological factor,locational condition,history background,development of productivity and progress of society etc.