Simulation And Analysis Of Soil Erosion On Slope Surface In Loess Hilly And Gully Region

Slope erosion is one of the important ways of soil erosion in Loess hilly and gully region.Simulate soil erosion in the Loess hilly and gully r egion is an important means to reveal the soil erosion law in this area.We got low altitude remote sensing data,and analyzed the characteris tics of the underlying surface of 19 samples as Loess hilly gully region,E arth rock mountain area and Loess tableland area.In order to reveal the e rosion characteristics of Loess hilly and gully region and the non loess hil ly gully area,the soil erosion of the Loess hilly gully region was simulat ed by the distributed water sand linkage model called LCM-MUSLE.The results show that:?1?compared with the Earth rock mountain area and the Loess tablela nd area,the topography of the underlying surface of Loess hilly and gully region is the most complex.It has smaller main ditch coefficient????=0.26?and channel opening degree????=1.56?,and larger channel density????=35.92?and ground split degree????=0.85?.The number of straight furrows is th e largest and the terrain is the most broken.The loess tableland area has a large main channel coefficient????=0.41?and channel opening degree????=2.99?,but the number of the trench density is the least????=33.37?,the terr ain is gentle,and the topographic condition of the underlying surface is th e simplest.The main gully coefficient of the Earth rock mountain area is less than the Loess Plateau area but more than the Loess Hilly and gully area????=0.35?.It has a larger channel density????=45.61?,and the numbe r of the trench is less than the Loess hilly gully region,but more than th e Loess tableland area.The terrain of the underlying surface is complex b etween the Loess hilly gully region and the loess tableland area.?2?The forest and terrace coupling area in Loess Hilly and gully regio n is largest.The proportion of pure forest and grass area shows Earth roc k mountain area?81.07%?>Loess hilly gully region?54.22%?>Loess tableland area?43.24%?,pure terrace area account for Loess tableland area?19.17%?>Loess hilly gully region?11.71%?>Earth rock mountain area?0.65%?,a nd the area of the coupling part of forest grass terrace is presented in Lo ess hilly gully region?21.53%?>Loess tableland area?6.03%?>Earth rock mountain area?0.2%?The proportion of other parts is Loess tableland area?31.56%?>Loess hilly gully region?18.13%?>the Earth rock mountain area?12.55%?.?3?Under the same rainfall condition,the runoff modulus and sediment yield modulus of Loess hilly gully region are located between the Earth rock mountain area and the Loess tableland area.The runoff modulus sho ws the characteristics of Earth rock mountain area(0.27m³·km^-2h^-1)>Loess hilly gully region(0.15m³·km^-2h^-1)>Loess tableland area(0.04m³·km^-2h^-1).The sediment yield modulus shows Earth rock mountain area(0.10t·km^-2h^-1)>Loess hilly gully region(0.05t·km^-2h^-1)>Loess tableland area(0.01t·km^-2h^-1).?4?in the terrain factors affecting runoff and soil erosion in Loess hil ly gully region,channel density and main gully coefficient have great influ ence.In the Loess Hilly and gully region,the positive correlation between te rrain factors and runoff modulus is?R²=0.83?>slope?R²=0.03?,and the negati ve correlation in turn shows the main trench coefficient?R²=0.78?>channel opening degree?R²=0.72?.The positive correlation between topographic fac tors and soil erosion modulus showed a sequence of channel density?R²=0.83?>gradient?R²=0.03?,and the negative correlation in turn showed the m ain ditch coefficient?R²=0.46?>channel opening degree?R²=0.25?.?5?Terraced area has great influence on land use factors affecting runo ff and soil erosion in Loess hilly gully region.Soil erosion modulus of 14 plots in Loess hilly gully region showed a significant negative correlatio n with the area of pure terraced fields?R²=0.30?.This indicates that terra ced fields have a significant mitigating effect on soil erosion in Loess hill y gully region.With the increase of vegetation coverage,runoff modulus decreased?R²=0.12?and soil erosion modulus decreased?R²=0.2?.The effe ct of terraced field on abortion and sediment is stronger than that of vege tation.?6?The results of soil erosion simulation with low altitude remote sens ing data were compared with the results of soil erosion simulation with lo w resolution remote sensing data.The effect of vegetation on soil erosion was reduced,and the effect of human activity on soil erosion was impro ved.Through the study,we can reveal the characteristics and influencing f actors of soil erosion on the slope in the Loess hilly gully region,which can provide a theoretical reference for the regulation of water and sedimen t in the Yellow River.