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Arid and semiarid lowland areas of central Asia are largely dependent on fluvial water originating from the Tian Shan. Mountain glaciers contribute significantly to runoff, particularly in summer. With global warming, the total glacier area in the Kunma Like River catchment declined by 13.2% during 1990–2007. For future water resources, it is essential to quantify the responses of hydrologic processes to both climate change and shrinking glaciers in glacierized catchments, such as the headwaters of the Tarim River. Thus, a degree-day glacier melt algorithm was integrated into the macroscale hydrologic Variable Infiltration Capacity model (VIC). Good results were obtained for monthly runoff simulations in the Kunma Like River catchment, which suggest that the extended VIC has acceptable performance. Because of increased precipitation and air temperature, annual runoff in the catchment has increased by about 4.07 × 108 m3 decade−1 during 1984/85–2006/07. Under the assumption of the same climatic conditions, sensitivity analyses indicated that annual and summer river runoff volumes would decrease by 9.3% and 10.4%, respectively, for reductions in glacier area of 13.2%. The variation coefficient of annual runoff also increased because of shrinking glaciers. Runoff scenarios for warmer future climate and various deglaciation situations suggest that reductions in glacier area by >30% will likely produce less meltwater in summer and river runoff will decline. Consequently, the annual total discharge of the Kunma Like River is projected to decrease by 2.8%–19.4% in the 2050s scenario because of glacier shrinking.

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The severity of soil erosion is considered to vary according to the structure of the bench terrace and the ground cover conditions. Erosion losses were investigated in a field experiment based on 20 m × 5 m erosion plots on a 21 per cent slope in Southern China. Five plots were established for the present study. Rainfall, runoff and sediment yield from plots were recorded for 5 years (2001–2005) and which five different types of terraces on sloping red soil were compared. The results show that the planting of grass on the riser is the most important factor affecting runoff and sediment yield, the next most important factor was the construction of a bund built on the edge of the terrace. Although the terrace bed slope (slope < 5 degrees) does not significantly affect the runoff, it does benefit the soil. A terrace combined with vegetation measures is effective in controlling runoff and soil erosion. Among various terraces, the level terrace (i.e. grass planted on the riser and bunds built on the edge of a bench terrace) is apparently the most beneficial for soil conservation purposes, indicating that this type is an excellent choice for conserving soil and water resources in sloping red soil in Southeastern China. Copyright © 2012 John Wiley & Sons, Ltd.