Study On Soil Erosion Characteristics Of Different Land Use Types During Spring Thawing Period

In northeastern China,repeated freezing and thawing and snowmelt/rainfall runoff during the thaw period in spring have destroyed the stability of the soil and caused serious soil erosion.The forms of land use will vary for different types of land use.Therefore,different types of land during the thaw period in spring are developed.The use of type soil erosion characteristics studies will help prevent soil freeze-thaw erosion and establish reasonable soil and water conservation measures.This paper selects the Quanhe small watershed and Jixing small watershed in the hilly area of Changbai Mountain in the northeastern black soil area as the research object.Based on the analysis of the land use pattern of the small watershed,typical types of land are selected to investigate soil and soil properties during the thawing period and the thawing period is analyzed.The main influencing factors of soil erosion,and the use of stepwise regression analysis to establish a prediction model of soil erosion and erosion factors in the thawing period,the main results obtained are as follows:(1)The types of land use in small watersheds are dominated by cultivated land and woodland.They have the following features in elevation,slope,and slope spatial pattern.The elevations are mainly distributed in the range less than 500m,and the forest lands in Jixing small watershed are mainly distributed in 500m.In the range of~800m,the cultivated land is mainly distributed within a slope of less than 15°,and the garden,woodland,and grassland are mainly distributed in a range of 8°to 25°.The slope direction is mainly distributed in semi-sunny slopes and semi-shady slopes.The analysis of the landscape index pattern found that the cultivated land and woodland showed more complex shapes,the forest land had the greatest dominance,the diversification and equalization development of the two small watersheds was poor,and the control of a few major landscape types was relatively high.(2)Among different types of land use,the temperature during the thawing season is the highest and the temperature difference is the largest,followed by grassland.The forestland has the lowest temperature and relatively small temperature difference,while the air humidity is the largest in the forest,and the temperature and humidity of the forest land and grassland are significantly different from the cultivated land.Both woodland and grassland have thick litter layers,and there are extremely significant differences between them and cultivated land.In terms of soil properties,the soil moisture content in the thawing period was highest,followed by grassland,and the soil moisture content was the lowest,while the soil temperature was the largest in cultivated land,followed by grassland,with the smallest forest land,and the soil reflected radiation was consistent with the soil temperature law.The cultivated land>grassland>In the woodland,the shearing force of the soil is woodland>grassland>cultivated land,and the woodland and grassland above-mentioned indicators are significantly different from the cultivated land.Observing the state of soil erosion during thawing,it was found that the soil erosion occurred mainly in arable land during the thawing season in spring,but little soil erosion occurred in the thawing period of woodland and grassland.(3)Investigating the arable soil erosion in thawing period,it was found that the soil erosion at different slopes was down slope>slope>slope,and the amount of soil erosion increased with the increase of local slope,and the amount of soil erosion at different slopes was south The slope is the largest and the north slope is the smallest.Different soil slopes and different local slopes showed significant differences in soil erosion,but there were significant differences between different slopes.(4)The grey correlation analysis shows that the degree of grey correlation between slope and soil erosion is the largest,the grey correlation degree of soil moisture ranks second,and the grey correlation degree of soil shear ranks third,while soil temperature and soil reflectance radiation The degree of grey correlation is small and has little effect on soil erosion.The correlation analysis further showed that the slope,soil moisture content and soil erosion were highly significantly positively correlated.The correlation coefficients were0.847 and 0.747,respectively.The soil shearing force was significantly negatively correlated with the amount of soil erosion,and the correlation coefficient was-0.7.Both soil and soil reflectance showed a significant positive correlation with soil erosion,but the correlation was small.Through stepwise regression analysis,a prediction equation for soil erosion amount based on slope,soil water content,and soil shearing force during thaw is established(V=-16.388+1.959S+2.038?-101.903?R~2=0.903).