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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]

Climate and land-use changes could strongly affect wind erosion and in turn cause a series of environmental problems. Thus, the objective of this study was to assess potential wind erosion rate (PWER) response to climate and land-use changes in the watershed of the Ningxia-Inner Mongolia Reach of the Yellow River (NIMRYR), China. The watershed of NIMRYR suffers from serious wind erosion hazards, and over recent decades, wind erosion intensity and distribution has changed, following climate and land-use changes. To understand these processes in the NIMRYR watershed, the Integrated Wind Erosion Modelling System (IWEMS) and the Revised Wind Erosion Equation (RWEQ) were used to calculate the PWER under different climate conditions and land-use scenarios, and to assess the influences of climate and land-use changes on the PWER. The results show the PWER in the whole watershed had a significant declining trend from 1986 to 2013. The results of the relationship among PWER, climate change, and land-use changes showed that climate change was the dominant control on the PWER change in this watershed. Compared to the period 1986-1995, the average PWER decreased 23.32% and 64.98% as a result of climate change in the periods 1996-2005 and 2006-2013, respectively. In contrast with climate change, the effects of land-use changes on the average PWER were much lower, and represented a change in PWER of less than 3.3% across the whole watershed. The study method we used could provide some valuable reference for wind erosion modelling, and the research results should help climate and land-use researchers to develop strategies to reduce wind erosion. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Fenhe River is the second largest tributary of the Yellow River in China. Climatic variation and human activities have impacted the runoff significantly in the Fenhe River in recent decades. In this study, the runoff trend from 1957 to 2010 was analyzed and the impacts of climatic variation and human activities on runoff were attributed by the climate elasticity method and hydrological modeling method. The observed annual runoff decreased significantly ( P < 0.05) during the past 54 years in the Fenhe River basin. A change point was identified around the year 1979 for the annual runoff series by the Mann-Kendall test. The observed average annual runoff in the Period II (from 1980 to 2010) decreased by 24.94 mm compared with the Period I (from 1957 to 1979). The attribution results show that the average annual amount of water diversion from the river in the Period II increased significantly by 7.88 mm compared with the Period I, accounting for 31.6 % of the total decrease in the observed annual runoff. In addition, other human activities such as land use and cover change led to the decrease in annual runoff by 6.31 mm from the climate elasticity method and 6.92 mm from the hydrological modeling method, which accounting for 23.8 and 27.7 % of the total decrease in the observed annual runoff, respectively. Therefore, human activities together were responsible for 55.4 % of the total observed runoff reduction estimated by the climate elasticity method and for 59.3 % estimated by the hydrological modeling method. Climatic variation such as changes in precipitation and evapotranspiration led to the decrease in runoff by 10.14 and 10.75 mm from the two methods, accounting for 40.7 and 44.6 % of the total observed runoff reduction. Therefore, human activities were the main driving factor for the runoff decrease in the Fenhe River basin. [ABSTRACT FROM AUTHOR]

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