THE TEMPORAL AND SPATIAL DISTRIBUTION OF SETTLEMENT SITES AND THE INFLUENCE OF ENVIRONMENTAL CHANGES SINCE THE NEOLITHIC TO CHUNQIU PERIODS IN CENTRAL AND SOUTHERN HEBEI PROVINCE
There is a close relationship between the history of human culture development and the characteristics of natural environment and its evolution. The study on the change of the distribution characteristics of the settlement sites in different regions will be helpful to deepen the understanding and cognition of the human-environment relationship. In this paper, the central and southern Hebei Province was selected as the study area, which is one of the original areas of Chinese millet agriculture,and an important area of ancient Chinese culture and ancient civilization. Hebei Plain and the Taihang Mountains are two most important geomorphic units in the study area. In this paper, we first establish a database of 1023 settlement sites from Neolithic to Chunqiu periods of which 202 settlement sites belong to the Neolithic settlement sites, 535 settlement sites belong to Xia-Shang period settlement sites, and 286 settlement sites belong to XiZhou-Chunqiu period. Based on the method of GIS spatial analysis, the site domain,altitude,density and accumulation characteristics of the settlement were systematically analyzed,and the temporal and spatial distribution characteristics of the settlement sites in the study area are revealed. The results show that: (1) From Neolithic to Xia-Shang Period,the settlement sites numbers,the domain area and average densities of the settlement sites increase rapidly; and then decrease rapidly in the Xizhou-Chunqiu period, whereas the ratio of the continually-stacked settlement sites amounted to the highest in the Xizhou-Chunqiu period. (2) In the south of the study area,most settlement sites (more than 46%) were located in the piedmont hilly basin (100~500m) of the Taihang Mountain from Neolithic to Xia-Shang period, but the low altitude alluvial plain (less than 50m) become the major area accounted to 48% of the total at least in the Xizhou-Chunqiu period, that is in response to the climate change from warm and humid to cold and dry since Holocene Megathermal. But in the northern of the study area, it is mainly influenced by geomorphic features and distribution range of ancient Baiyangdian from the Neolithic to the Chunqiu period. The settlement sites were always mainly distributed in the Low alluvial plain where the altitude is less than 50m. (3) From Neolithic to Xia-Shang period, the climate is warm and humid, and the distribution center of settlement sites is located in the south of the study area, with the center appeared in Wu'an Basin in Handan (84~103/10000km~2) settlement site densities in the Neolithic, and then slightly northward moved about 50km to the south of Xingtai and the northern part of Handan (171 ~ 220/10000km~2) in the Xia-Shang period. Further more, cold and dry climate made it difficult for people's survival and development in the original area during the Xizhou-Chunqiu. Shang people began to migrate southward to search more suitable farming land in the south of the study area, and some nomadic people also began to move to the south and integrated with the farming nationality in the northern of the study area,adding to the establishment of the Yan state,which made the distribution center of settlement sites in the Xizhou-Chunqiu period move to the middle and lower reaches of the Juma River Basin (< 50m a. s. l.) located in the north of the study area with settlement site densities about 99~121/10000km~2. (4) From Neolithic to Chunqiu periods, most settlement sites appeared in the western part of the study area, along the foothills of Taihang Mountain, and very few settlement sites appeared in the south-eastern plain area due to the influence on the downstream diversion of ancient lakes and river diversion, flood and other factors.