Study On The Development Of Gully And Characteristics Of Vegetation In The Black Soil Region Of Northeast China

The black soil area in Northeast China is affected by unreasonable agricultural practices,geological features and climatic conditions.The gully has developed extensively and has become one of the most severe areas of gully erosion in China.As an important measure to control gully ditch erosion,vegetation plays an important role in inhibiting the development of gully and improving the environment inside the gully.However,the general soil parent material in the gully is exposed,the gully slope is steep,and the vegetation growth environment is bad.It is clear that what vegetation can survive under this condition is essential for the ecological management of gully.At present,there is little research on the relationship between the environment of gully and the growth of vegetation in the black soil area of Northeast China.The dominant species of vegetation in the gully is still unclear.The lack of theoretical basis severely restricts the scientific and effective work of vegetation restoration in the gully.In order to clarify the development of the gully in the main growth period of the black soil area and the characteristics of the vegetation in the gully,and to clarify the coupling relationship between the two,the study area selected four typical areas with prominent development characteristics of the gully in the black soil area.Through the observation and analysis of the development rate and development position of the gully in the vegetation growth period,the channel development characteristics of each typical watershed and the species composition of the vegetation within the gully were determined.Through the comparative analysis of the vegetation in the gully ditch of the typical watershed in different locations in the black soil area,the geographical differentiation characteristics of the dominant species in the vegetation community were clarified.The observation of three main soil and water conservation artificial plant measures and natural vegetation growth in the gully found that different soil and water conservation artificial plant measures have significant differences in the restoration of natural vegetation in the gully.Artificially planted poplar and willow have the best effect on natural vegetation restoration in the gully.Adopting various artificial soil and water conservation plant measures can effectively improve the variety and quantity of natural vegetation,improve community diversity,and facilitate the stability of gully.The study on the coupling relationship between “slope direction-main species-vegetation coverage” and “slope-vegetation coverage” in the gully shows that the topographical conditions in the gully are closely related to the growth of vegetation,and the sloping slopes on both sides of the shady and sunny.The vegetation coverage varies greatly,and the vegetation coverage types and thresholds under different slopes are also different.60° is the slope threshold of suitable vegetation growth in the gully in the black soil area of Northeast China.Vegetation growth is occasionally in the range of 60° to 75°,which is the critical slope of vegetation survival in the gully of the four watersheds.The main features and innovations of the thesis are as follows: Based on the definition of the main vegetation types in different gullies in the black soil area,and determining the regional differences of the dominant vegetation species in the gully,the main artificial plant measures are clarified for the natural vegetation in the gully.The relationship of growth determines the extent of the slope of the sloping vegetation that can grow in the gully of the black soil area.In the research method,the method of sample and low-altitude drone aerial photography is used to accurately extract and systematically analyze the vegetation in the gully,to a certain extent,it avoids the one-sidedness of the previous methods of remote sensing to determine the vegetation information on the micro-topography in the gully.The research results provide a new basis for judging the developmental stage of the gully,and lay a good theoretical foundation for the rational selection and layout of the gully vegetation measures in this area.