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Pisha sandstone is a special kind of soft rock in the semiarid region along the up and middle reaches of Yellow River and Loess Plateau and is severely eroded by wind, rainfall and gravity force. Pisha sandstone region is called “the most severe water loss and soil erosion in the world” and referred to as the “Earth Cancer” by local residents and experts both at home and abroad. The plan for the control of Pisha sandstone started in the 1950s. Since then a series of projects have been implemented, both engineering and vegetation measures have been developed and widely used to protect Pisha sandstone from erosion. Since seabuckthorn was introduced as a viable approach for soil erosion protection and its implementation resulted in a breakthrough to control Loess Plateau, it was considered as an important and efficient measure. Then the seabuckthorn flexible dam was proposed for coarse sediment retention and fine sediment deposition. And then a new comprehensive control model using consolidation materials combined with vegetation was proposed and promising results were achieved both in laboratory and field demonstrations. In the future, the complex erosion mechanism and ecological carrying capacity should be studied further and more efficient and practical comprehensive measures shall be developed. Moreover, monitoring systems shall be used to predict and detect the changes in the Pisha sandstone slope and structure.

Improved understanding of the effect of shrub cover on soil erosion process will provide valuable information for soil and water conservation programs. Laboratory rainfall simulations were conducted to determine the effects of shrubs on runoff and soil erosion and to ascertain the relationship between the rate of soil loss and the runoff hydrodynamic characteristics. In these simulations a 20° slope was subjected to rainfall intensities of 45, 87, and 127 mm/h. The average runoff rates ranged from 0.51 to 1.26 mm/min for bare soil plots and 0.15 to 0.96 mm/min for shrub plots. Average soil loss rates varied from 44.19 to 114.61 g/(min·m2) for bare soil plots and from 5.61 to 84.58 g/(min·m2) for shrub plots. There was a positive correlation between runoff and soil loss for the bare soil plots, and soil loss increased with increased runoff for shrub plots only when rainfall intensity is 127 mm/h. Runoff and soil erosion processes were strongly influenced by soil surface conditions because of the formation of erosion pits and rills. The unit stream power was the optimal hydrodynamic parameter to characterize the soil erosion mechanisms. The soil loss rate increased linearly with the unit stream power on both shrub and bare soil plots. Critical unit stream power values were 0.004 m/s for bare soil plots and 0.017 m/s for shrub plots.

The Yellow River basin is well known for its high sediment yield. However, this sediment yield has clearly decreased since the 1980s, especially after the year 2000. The annual average sediment yield was 1.2 billion tons before 2000, but has significantly decreased to 0.3 billion tons over the last 10 years. Changes in discharge and sediment yield for the Yellow River have attracted the attention of both the Central Government and local communities. This study aimed to identify the individual contributions of changes in precipitation and human activities (e.g. water conservancy projects, terracing, silt dams, socio-economic and needs, and soil and water conservation measures) to the decrease in discharge and sediment yield of the Yellow River. The study used both improved the hydrological method and the soil and water conservation method. The study focused on discharge analysis for the upper reaches and the investigation of sediments for the middle reaches of the river. The results showed that discharge and sediment yield have both presented significant decreasing trends over the past 50 years. Precipitation showed an insignificant decreasing trend over the same period. The annual average discharge decreased by 5.68 billion m3above Lanzhou reach of the Yellow River from 2000 to 2012; human activities (e.g. socio-economic water use) contributed 43.4% of the total reduction, whereas natural factors (e.g. evaporation from lakes, wetlands and reservoirs) accounted for 56.6%. The decrease in annual discharge and sediment yield of the section between Hekouzhen station and Tongguan station were 12.4 billion m3and 1.24 billion tons, respectively. Human activities contributed 76.5% and 72.2% of the total reduction in discharge and sediment yield, respectively, and were therefore the dominant factors in the changes in discharge and sediment yield of the Yellow River.

The soil covered Pisha stone area is the core source area of the coarse sediment in the Yellow River, it has become the focal point of the ecological control of the Yellow River Basin. It has important value to study the spatial distribution about geomorphologyl-vegetation- water Erosion coupling in the soil covered Pisha stone area. Some valuable research results have been obtained by using high-definition remote sensing aerial photographs and unmanned aerial vehicle high precision data interpretation, Especially the image resolution obtained by unmanned remote sensing to obtain the spatial structure features of small watershed topographic features or vegetation structure characteristics. Use remote sensing to study the spatial distribution characteristics of soil erosion in the Pisha stone area slope and the regular response with time change on the geomorphic spatial structure of the slope is very important, the negative response relation between the spatial structure of the vegetation community and the energy dissipation impedance erosion need be study. It will be an urgent scientific problem to promote the research progress of soil erosion in pisha stone area, which will directly affect the theoretical foundation of the comprehensive treatment model of soil erosion in Pisha stone area.