The settlement is a product of the man-land relationship,and the selection of places for building settlements must satisfy the demand of human survival.In the Xinglongwa and Zhaobaogou cultures(a.8000—6000 BP),people made a living mainly by gathering,fishing and hunting,and their settlements were located within the boundary of timberland suitable to those economic activities.Investigation shows that these settlements were largely concentrated on hill-slopes at a height of 400—600 m above sea level,while the mountain summits and river valleys beyond the limits played a part in this respect only during certain periods.Meanwhile,the West Liaohe River valley was one of the birthplaces of civilization.In the Hongshan and Upper Xiajiadian cultures(a.6000—3000 BP),the weather was becoming cold and dry,primitive agriculture increased its proportion in the means of subsistence,and the population grew step by step,all of which caused the distribution of settlements to be expanded from timberland to lower grassland.In the Hongshan culture,farming began to play the leading role,whereas by the Upper Xiajiadian period,it had been supplemented by animal husbandry.Every change in the mode of man’s getting food was embodied in the relationship between the settlement and the environment:Gathering,fishing and hunting were entirely dependent on natural environment;the agriculture’s joining in decreased man’s dependence on the natural world;and the breakthrough in the selection of the environment of settlements by expanding living space from timberland was just a result of promotion by agricultural production.Both the duration of settlement function and the alteration of settlement culture prove that the man-land relationship in the prehistoric West Liaohe River valley was kept in a state of relative balance.Either gathering,fishing and hunting in the Xinglongwa and Zhaobaogou cultures or agricultural production from the Hongshan period did not break through the environmental content of this region.The gathering,fishing a
