Geomorphological regionalization (geomor-region) and geomorphological type (geomor-type) classification are two core components in the geomorphologic research. Although remarkable achievements have been made in the study of geomor-region, many deficiencies still exist, such as the inconsistency of landform indicators, the small quantity of division orders, disparities of geomorphological characteristics, differences of mapping results, and the small scale of zoning maps. Requirements for improved national geomor-regions are therefore needed for the purpose of an enhanced national geo-information system. Based on theories of geomor-region in China including plate tectonics, crustal features, endogenic and exogenic forced geomorphological features, and regional differentiations of geomor-type, a three-order (major-region, sub-region, and small-region) research program on China's geomor-regions is proposed on the basis of previous 2013 geomor-region system. The major contents of the new geomor-region scheme are: (1) principles of the national multi-order geomor-regions; (2) hierarchical indicator systems of geomor-regions including characteristics of the terrain ladder under the control of tectonic setting, combinations of regional macro-form types, combinations of endogenic and exogenic forces and basic types of morphology, combinations of regional morphological types, and combinations of regional micro-morphological types; (3) naming rules and coding methods of geomor-regions; and (4) precise positioning techniques and methods of multi-order geomor-region divisions based on multi-source data. Using the new geomor-region theory and division methodology, the partition of national three-order geomor-regions of China was successfully constructed. The geomor-region system divided China into six first-order major-regions, 36 second-order sub-regions, and 136 third-order small-regions. In addition, a database and management information system of the national geomor-regions were established. This research has an important guiding significance for promoting the development of China's regional geomorphology and for practical applications based on geomor-regions.

Research on habitat quality change is of great significance for regional ecological security. Analysis of spatiotemporal change of habitat quality based on different geomorphic types can restore the background of ecological environment in historical periods and provide scientific support for revealing the evolution law of regional ecological environment quality and ecological restoration. This study aimed to identify the change in habitat quality under different geomorphic types from 1995 to 2018. Based on DEM data, geomorphic types of different scales were divided. The InVEST habitat quality model was used to analyze the spatiotemporal change in habitat quality in individual land use types in the Altay region. The spatiotemporal changes and main influencing factors of habitat quality under the background of different geomorphic types were explored. Remote sensing data was used to analyze the land use/cover changes. Sixteen threat sources, their maximum distance of impact, mode of decay, and sensitivity to threats were also estimated for each land use type. The results showed that habitat quality decreased significantly in 2015, which was related to the rapid expansion of cultivated and construction land as threat sources, as well as the decrease of forestland and grassland as sensitive factors. However, habitat quality improved significantly in 2018, because of the implementation of ecological restoration policy in 2015. Affected by elevation and topographic relief, the geomorphic type with the best habitat quality index was the large undulating middle mountain (0.927) and the worst was the medium altitude platform (0.351). Woodland contributed the most to habitat quality in large undulating middle mountain (35.07), and bare rock gravel land contributed the most to medium altitude platform (127.68). Habitat quality of different geomorphic types showed obvious spatial aggregation, and from high altitude to low altitude showed a banded ladder-like distribution. Changes in habitat quality during the past three decades suggested that the conservation and restoration strategies applied in regional ecosystem were effective. On the basis of the analysis results, four types of zoning management schemes were divided, and the ecological management and conservation measures were put forward. Therefore, this study can help decision makers, especially regarding the lack of data on biodiversity.