关键词: 坡耕地, 聚落, 空间耦合, 人地协调, 奉节县

Abstract:

Based on the natural background of land bearing capacity difference in the lithology and landform areas, we put forward that in different lithology and landform in the hinterland of the Three Gorges Reservoir Area, because the land bearing capacity is different, then, the interactions, the response and feedback between people and land are different also, further, there is the difference of number and the spatial distribution pattern of settlements from the view of man-land relationship, and showing different process and intensity of ecological degradation, such as soil erosion and so on, so that the diversity and different adaptability of man-land relationship are formed in different lithology and landform areas of Three Gorges Reservoir Area. The coupling relationship between sloping cultivated lands and the settlement is an important factor influencing the suitability of man-land relationship. We took the settlement on behalf of the "people", the sloping cultivated lands and soil erosion on behalf of the "ground" (environment), and chose the 27 towns of Fengjie County located in the center region of the Three Gorges Reservoir Area as the study case, revealed the allocation relationships of between settlements and sloping cultivated lands and the difference of coupled mode between settlements and sloping cultivated lands on different lithology, and made type division of the man-nature of study area applying grid unit analysis technology to divide 1 km x 1 km grid as the research unit. The results showed that: a) The spatial distribution of settlements and sloping cultivated lands presented strong space convergence, the high proportion and the higher patch’s grade of settlements and sloping cultivated lands distribute mainly at the Meixi river valley in the north and the Yangtze river valley in the middle, the low area of them distribute mainly at exposed limestone area of the southern study area. b) Of all the coupling relationship types of sloping cultivated lands and settlements, the type of more sloping cultivated lands distributed mainly at exposed sandstone region and the type of less sloping cultivated lands distributed mainly at exposed limestone region, and the type of which settlements and sloping cultivated lands keep balance present random distribution pattern. c) The reasons of the sloping cultivated lands abound in study area were attributed to the large number of sloping cultivated lands and the difficult to shift from agricultural use. The soil erosion of the coupling type of more sloping cultivated lands is more serious than other coupling type because of the distribution of more sloping cultivated lands. d) The man-land relationship of the 27 towns are divided into four types such as the salient type of contradiction, the less salient type of contradiction, the less assuasive type of contradiction, the assuasive type of contradiction, and the area with less salient region of contradiction between human and land accounted for the largest, therefore, there is facing the dual problems of the cultivated land from grain to green and cultivated land pressure. On the one hand, this research results verify the effectiveness of the theoretical assumptions proposed by this paper and can provides the theory basis for the sloping cultivated lands utilization and the implementation to coordinate man-land relationship in the hinterland of the Three Gorges Reservoir Area, on the other hand, it is also a beneficial attempt and supplement for the study on the regional man-nature relationship.

Key words: sloping cultivated land, settlement, spatial coupling, man-nature harmonization, Fengjie county