Characteristics Of Wind-sand Movement In Photovoltaic Power Station And Effects Of Vegetation Restoration On Soil

Through field observation and laboratory experiment,this study explored the influence of photovoltaic array on airflow field and sediment transport,as well as the influence of soil particle size characteristics,which laid a theoretical foundation for sand damage prevention and control of photovoltaic power stations in sandy areas,and analyzed the influence of different vegetation restoration measures in photovoltaic array on soil,in order to provide data support for ecological restoration of photovoltaic power stations in desert.It provides ideas for scientific planning of surface sand control technology scheme of photovoltaic power station in sandy area.The main research conclusions are as follows:1.The main winds in the study area of PV power stations were West wind and Northwest wind.The upwind wind speed in the edge area of the PV array decreased first and then increases with the change of height.The wind speed at each observation height in the abdomen of the PV array was lower than that in the upwind edge area.The surface airflow near the ground in the edge area of the PV array and the upwind direction of the abdomen was easy to form a vortex,and the surface roughness was larger than that in the bare sand area.The roughness of the front,behind and under of the panels in the abdomen of the power station was 80.49%,69.23%and 17.17%higher than that of the upwind array edge area.2.The sediment transport flux at different positions of the plate at the edge of the PV power stations was greater than that in the abdomen of the power stations with the increase of wind speed in the height of 0～10 cm.The characteristic value of the wind-sand flow structure between and behind the plate wasλ<1.The characteristic value of the wind-sand flow structure in front of the plate wasλ>1.The wind-sand flow was in an unsaturated state before passing through the plate,and the sediment carrying capacity increased,which was prone to wind erosion.Under different wind speeds,the power function and exponential function could well simulate the variation of sediment transport in the upwind edge area of the PV array with height,and the correlation coefficient was R~2=0.97.The variation of sediment transport with height in the abdominal PV array was best fitted by polynomial function,R~2>0.88.3.The sediments of the PV power stations were mainly fine sand and medium sand.The fine sand accounts for 74.23%～78.46%,and the medium sand accounts for 18.32%～72.63%.The PV power stations showed a trend of soil particle refinement from the outer edge to the abdomen.The variability of fine sand in front,behind,under of the plate in the upwind edge area and abdomen of the power stations was the largest,reaching 37.36%.The skewness of surface soil particles in the PV power stations was negative,and the sediment particles were generally coarse.4.Under the vegetation restoration measures such as Hedysarum scoparium,Artemisia ordosica,Glycyrrhiza uralensis and Leymus chinensis,the soil fine sand content of PV power stations increased by 29.07%,32.16%,21.06%and 25.07%respectively compared with the control.Among them,the fine sand content under the Leymus chinensis measure increased by 314.95%.In different vegetation restoration areas,soil bulk density decreased significantly and water holding capacity increased compared with the control.