北方农牧交错带农村居民点分布特征及其对土地利用的影响——以科尔沁左翼中旗为例

选取农牧交错带的典型地区--科尔沁左翼中旗作为研究区,对不同海拔、坡度、坡向等要素上农村居民点的分布特征进行了研究,分析农村居民点对农牧交错带内土地利用格局的影响。结果表明:① 居民点主要分布在海拔200 m以下,坡度小于6°的地区以及阴坡上;② 农村居民点对土地利用格局有着直接影响,居民点密度越高的地区,耕地所占比重越大,草地越少;反之,则草地所占比重越大,耕地越少;③ 在牧业区,距离居民点越远,草地比例越小,耕地比例越大,农业区和农牧区则相反。

Spatial Distribution of Rural Settlements in Farming-pastoral Zone of Northern China and Its Impact on Land Use Pattern:A Case Study of Korqin Left Wing Middle Banner

Settlements are places of habitation, production and the living places for people. This article selected Korqin Left Wing Middle Banner as the study area, which was a typical farming-pastoral ecotone in the northern China. We selected elevation, slope, and aspect as factors that affected the distribution of rural settlements, and these factors were divided into 9, 6 and 8 grades, respectively. We conducted research about the distribution of rural settlements on different elevation, slope, aspect, and analyzed the impacts of rural settlements on land use pattern in ecotone between agriculture and animal husbandry. The results showed that: 1) Rural settlements mainly distributed in the areas that is from 0 m to 200 m above sea level, or where the slope is less than 6°, or shady slope. These are because the higher the altitude, the poorer living conditions are, which make it is difficult to build house and road. Moreover, the elevation also affects the precipitation and temperature that are critical for farming and grazing. Generally speaking, slope is a very impotent factor influencing the distribution of rural settlements. However, due to the study area is flat, we cannot find an obviously change trend of settlements density on different slope gradients. Affected by freeze-thaw action, settlements density on the shady slope is greater than that on the sunny slope. 2) Rural residential has a direct impact on land use pattern, the greater the rural settlement density, the greater proportion of agriculture land and the less proportion of grassland, and vice versa. The total area of cultivated land that located within 2 000 m away from the settlements is 2 701.90 km2, representing 74.4% of the total arable land; the grassland mainly distributed in the areas that farther away more than 1 500 m, The total grassland that within 1 500 m from the settlements only 35.1% of the total grassland, about 1 391.83 km2. In addition, according to the proportion of arable land and grassland within each town, the study area can be divided into agricultural region (cultivated land proportion > 50%), pastoral region (grassland proportion > 50%), agricultural and pastoral region (cultivated land proportion < 50% and grassland proportion < 50%). In agricultural region and pastoral region, the distribution of farmland and grassland around residential areas followed the same pattern: the farther away from the settlements, the less proportion of cultivated land and the higher proportion of the grassland. However, the situation is the opposite in pastoral region: the farther away from the settlements, the higher proportion of cultivated land, and the proportion of grassland away from residential areas within 2.5 km remain unchanged on the whole.