The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we co...The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we conducted field simulated wind erosion experiments combined with laboratory analysis to investigate wind erosion of soils in trampled rangeland, non-tilled cropland and tilled cropland in Yanchi County, China. The results showed that compared with rangeland, the cropland had a higher soil water holding capacity and lower soil bulk density. The wind erosion rate of trampled rangeland was much higher than those of non-tilled cropland and tilled cropland. For cropland, the wind erosion rate of the soil after tilling was surprisingly less than that of the soil before tilling. With increasing of wind speed, the volume mean diameter of the eroded sediment collected by the trough in the wind tunnel generally increased while the clay and silt content decreased for all soils. The temporal variation in wind erosion of the trampled rangeland indicated that particle entrainment and dust emission decreased exponentially with erosion time through the successive wind erosion events due to the exhaustion of erodible particles.展开更多
In the present study,indoor experiments were carried out to investigate the effects of rainfall on subsequent wind erosion processes on the simulated Gobi surface,with soils and gravels collected from the Alax Gobi in...In the present study,indoor experiments were carried out to investigate the effects of rainfall on subsequent wind erosion processes on the simulated Gobi surface,with soils and gravels collected from the Alax Gobi in northwestern China.The results showed that the wind erosion rate(WR)ranged from 0.4 to 1931.2 g m^((-2)min^((-1)and that the sediment transportation rate(STR)ranged from 0.00 to 51.47 g m^((-2)s^((-1)under different gravel coverage conditions(0%,20%,40%and 60%)when the wind velocity changed from 6 m s^((-1)to 18 m s^((-1).Both WR and STR increased with increasing wind velocity as a power function and decreased with increasing gravel coverage.The rainfall event had significant inhibitory effects on WR and STR,and the complex effects of soil crust formation and the changing soil surface roughness(SSR)by rainfall event played significant roles in reducing these rates during subsequent wind erosion.In this study,a valuable exploration of the effects of rainfall events on subsequent wind erosion processes in the Gobi area was conducted.The findings are of great significance for a better understanding and effective prediction of dust emissions in this region.展开更多
基金supported by the National Natural Science Foundation of China (41401310, 41661003)the Science-Technology Research Project of Ningxia Environmental Protection Department
文摘The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we conducted field simulated wind erosion experiments combined with laboratory analysis to investigate wind erosion of soils in trampled rangeland, non-tilled cropland and tilled cropland in Yanchi County, China. The results showed that compared with rangeland, the cropland had a higher soil water holding capacity and lower soil bulk density. The wind erosion rate of trampled rangeland was much higher than those of non-tilled cropland and tilled cropland. For cropland, the wind erosion rate of the soil after tilling was surprisingly less than that of the soil before tilling. With increasing of wind speed, the volume mean diameter of the eroded sediment collected by the trough in the wind tunnel generally increased while the clay and silt content decreased for all soils. The temporal variation in wind erosion of the trampled rangeland indicated that particle entrainment and dust emission decreased exponentially with erosion time through the successive wind erosion events due to the exhaustion of erodible particles.
基金supported by The National Natural Science Foundation of China (Grant No. 40861013)Natural Science Foundation of Inner Mongolia (Grant No. 200508010708)
基金National Natural Science Foundation of China,No.41930640,No.41977069。
文摘In the present study,indoor experiments were carried out to investigate the effects of rainfall on subsequent wind erosion processes on the simulated Gobi surface,with soils and gravels collected from the Alax Gobi in northwestern China.The results showed that the wind erosion rate(WR)ranged from 0.4 to 1931.2 g m^((-2)min^((-1)and that the sediment transportation rate(STR)ranged from 0.00 to 51.47 g m^((-2)s^((-1)under different gravel coverage conditions(0%,20%,40%and 60%)when the wind velocity changed from 6 m s^((-1)to 18 m s^((-1).Both WR and STR increased with increasing wind velocity as a power function and decreased with increasing gravel coverage.The rainfall event had significant inhibitory effects on WR and STR,and the complex effects of soil crust formation and the changing soil surface roughness(SSR)by rainfall event played significant roles in reducing these rates during subsequent wind erosion.In this study,a valuable exploration of the effects of rainfall events on subsequent wind erosion processes in the Gobi area was conducted.The findings are of great significance for a better understanding and effective prediction of dust emissions in this region.
