Abstract: In this paper, based on classification method and legend layout of published geomorphological maps of the nation at different levels and different scales and the hierarchical classification method for the digital geomorphology of China with a scale of 1:1000000, we proposed a hierarchical land classification system with the indicators in five major categories. The indicators include basic landform form, morphological characteristics of geomorphological types (including morphological assembly, micro-landform morphological entities, slope form characteristics of landform surface), basic genesis and main genetic action ways, materials and lithology, formation age or period of geomorphological types, which all combined are a comprehensive presentation of geomorphological characteristics. These indicators can be divided into three categories and nine levels: landform superclass (sub-superclass), landform class (sub-class) and landform type (sub-type), at the nine levels, such as macro morphology, terrain characteristics, main genetic condition, main genetic action ways, morphological assembly, micro-landform morphological entity, slope characteristics, material and lithology and landform formation age. The geomorphological characteristics can be expressed by means of not only continuous polygons addressing morpho-genetic types, but also discrete points, lines and polygons addressing morpho-structural types. The morpho-genetic and morpho-structural geomorphological types can be exchanged for each other based on mapping scales. Based on geomorphological characteristics, the indicators of former four grades can be mapped for 1: 4000000 geomorphological maps, and former five grades for 1:1000000 geomorphological maps, and former seven grades for 1:500000 geomorphological maps. As to 1:250000 and 1:50000 geomorphological maps, parts of morpho-structural geomorphological types can be converted to morpho-genetic geomorphological types, slope form characteristics, terrain slope position, material and lithology and formation age of micro-landforms can be highlighted in order to realize the expression for detailed geomorphological types. As to China's offshore and adjacent ocean topography and geomorphology, four hierarchical geomorphological types can be classified in terms of spatial position, water dynamic condition (ocean water depth and slope characteristics), and lithosphere types and depth change. Form-genetic types can be expressed by means of the former three classes and form-structural types can be expressed by means of fourth class.

Key words: digital geomorphology, geomorphological map, hierarchical classification system, multi-scale