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The farming-pastoral region of North China is a region that has suffered from serious desertification, and the multiple transitional characteristics in this region make it very difficult to link the progress of desertification to the driving forces behind it. This paper mainly focuses on the dynamics of desertification over the past 10 years and their relationship to climate change and human activity. According to the MODIS images in 2000 and 2010, the farming-pastoral region had experienced significant desertification dynamics over the past 10 years. The area of regions that had undergone desertification reversion and expansion were 186,240 km 2 and 199,525 km 2 respectively, and the spatial distribution of these regions showed great heterogeneity. The relationship between desertification dynamics and their driving forces was investigated by comparing the change in the NPP that was induced by climate change and human activity for each pixel that experienced desertification reversion and expansion. From 2000 to 2010, the coupling of climate change and human activity was the dominant factor behind desertification reversion. However, the human activity was the dominant factor that controlled the desertification expansion process between 2000 and 2010. The driving processes of desertification also had considerable spatial heterogeneity, and the dominant factors behind desertification reversion and expansion in each sub-region were not completely the same. So, the scale effect must be considered when explaining the results from similar studies. [ABSTRACT FROM AUTHOR]

Abstract: Water discharge and sediment load have changed continuously during the last half century in the Yellow River basin, China. In the present paper, data from 7 river gauging stations and 175 meteorological stations are analyzed in order to estimate quantitatively the contributions of human activities and climate change to hydrological response. Coefficients of water discharge (C w ) and sediment load (C s ) are calculated for the baseline period of 1950s–1960s according to the correlations between the respective hydrological series and regional precipitation. Consequently, the natural water discharge and natural sediment load time series are reconstructed from 1960s–2008. Inter-annual impacts are then separated from the impacts of human activities and climate change on the hydrological response of different regions of the Yellow River basin. It is found that human activities have the greatest influence on changes to the hydrological series of water discharge and sediment load, no matter whether the effect is negative or positive. Moreover, the impact of human activities is considerably greater on water discharge than sediment load. During 1970–2008, climate change and human activities respectively contribute 17% and 83% to the reduction in water discharge, and 14% and 86% to the reduction in sediment yield in the Upper reaches of Yellow River basin; The corresponding relative contributions in the Middle reaches are 71% and 29% to reductions in water discharge, and 48% and 52% to reductions in sediment load. Moreover, it is observed that the impacts of human activities on the whole basin are enhanced with time. In the 2000s, the impact of human activities exceeds that of climate change in the 2000s, with human activities directly responsible for 55% and 54% of the reductions in water discharge and sediment load in the whole basin. [Copyright &y& Elsevier]