Research on geomorphological regionalization of China

According to research achievements of Chinese regional geomorphology over nearly 30 years, including landscape classification and landform mapping, this paper systematically discusses the specific steps and methods, principles and the standards for geomorphological regionalization. It is suggested that the basis and standard of geomorphological zoning at all levels not only include the similarities and differences of the combinations of geomorphology type together with the landform genesis, but also its dimension. Based on 1:4000 000 geomorphplogical map of China and the GIS technology, we made an analysis of reasons for the Chinese regional differentiation of the essential geomorphological types and their genesis and divided the whole China into six major geomorphological regions and 38 districts. Region I (eastern hilly plains) is located in the northern part of the low terrain unit of China, in which the largest plain areas of China are distributed. Plains and platforms are dominant and the fluvial accumulation landforms are well developed. This region includes seven districts. Region II (southwestern low-middle mountains) is located in the southern part of the low terrain unit of China, which is dominated by low-elevation hills and low- or middle-relief mountains with only 30% of its area occupied by plain and platforms. Fluvial geomorphologies are typical with a developed karst landform in Southwest China, which can be divided into five districts. Region III (central and northern middle mountains and plateau) is located in the northeastern part of the middle terrain unit of China, characterized by the plateau landform composed of the low- or middle-relief mountains, hills, platforms and plains. Loess landform is well developed. This region includes five districts. Region IV (northwestern middle and high mountains and basins) is located in the northwestern part of the middle terrain unit of China. It is composed of middle to high mountains interposed by flattened basins and is characterized by arid desert geomorphology, where mountains with basins are made up of plains, platforms and hills. This region can be divided into five districts. Region V (southwestern subalpine mountains) is located in the southern part of the middle terrain unit. With a typical karst landform, middle or high mountains with middle or high reliefs are widespread and are scattered by wide valley basins. This region includes five districts. Region VI (Tibetan Plateau) covers the high terrain unit of China. It is composed of plains and high mountains with elevations higher than 4000 m and 3/4 area of the region, and is characterized by glacier and periglacial landforms. This region can be divided into nine districts.