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Owing to the influence of global change, land cover and land use have changed significantly over the last decade in the cold and arid regions of China, such as Madoi County which is located in the source area of the Yellow River. In this paper, land-use/cover change and landscape dynamics are investigated using satellite remote sensing (RS) and a geographical information system (GIS). The objectives of this paper are to determine land-use/cover transition rates between different cover types in the Madoi County over 10 years e.g., from 1990 to 2000. Second, the changes of landscape metrics using various indices and models are quantified. The impact factors of LUCC (Land-Use land cover Change) are systematically identified by integrating remote sensing as well as statistical data, including climate, frozen soil, hydrological data and the socio-economic data. Using 30 m×30 m spatial resolution Landsat (Enhanced) Thematic Mapper (TM/ETM+) data in our study area, nine land cover classes can be discriminated. Our results show that Grassland, Marshes and Water Bodies decrease notably, while oppositely, Sands - Gobi and Barren land increase significantly. The number of lakes with an acreage larger than six hectares decreased from 405 in 1990 to 261 in 2000. Numerous small lakes dried out. The area of grassland with a high cover fraction decreased as well, while the surface area of grassland with a medium level of cover fraction increased. The medium cover fraction grassland mainly originates from high cover fraction grassland. The desertification of land is a serious issue. (ii) The inter-transformations between Grasslands, Barren Land, Sands, Gobi, Water Bodies and Marshes are remarkable. The Shannon-Weaver Diversity Index (SWDI), the Evenness Index (EI) and the extent of Landscape Heterogeneity (LH) has improved. Marshes have become more fragmented hence, with less connected patches. (iii) In the recent 30 years, average annual temperature, the power of evaporation and the index of dryness did increase significantly. Moreover, soil moisture content (SMC) decreased and the drought trend accelerated. The degradation of frozen soil has impacted on the decrease of surface water area and induced a drop in groundwater levels. Monitoring LUCC in sensitive regions would not only benefit from a study of vulnerable ecosystems in cold and high altitude regions, but would provide scientifically based decision-making tools for local governments as well. [ABSTRACT FROM AUTHOR]

The ecological and environmental relationship between a natural reserve (NR) and its surrounding area is a ‘hotspot’ in the human–environment relationship. However, the effect of landscape pattern of the surrounding land-use changes on the NR has not been thoroughly explored. How to protect the NR has become an issue of major concern. This research analysed the land-use/land-cover (LULC) change of the NR and its surrounding area using Landsat Thematic Mapper (TM) images and applied theories of landscape ecology to study the effect of the surrounding LULC on the wetland landscape of the NR in Tianjin, China. The results show that (1) the wetland area decreased from 122,461.11 ha in 1988 to 111,753.99 ha in 2008 while the built-up area expanded from 11,983.22 ha in 1988 to 20,197.71 ha in 2008; (2) landscape diversity will increase along with direct LULC in the NR and its surrounding area, where human activities have already diversified the original wetland landscape; and (3) the unitary landscape has been replaced by diverse landscapes and the land type that was once dominant has lost its status. Restoring the watershed wetland is a good method for realising protection of the NR. [ABSTRACT FROM PUBLISHER]