The Evolution Features Of Valley System In Pingshuo Mining Area And Its Surrounding For 30 Years

The basic geomorphologic types as valley landforms are widely distributed on the Loess Plateau,soil erosion can cause a vicious spiral,also has ecological function,analysis of ravine landform characteristics and influence around mining area is of great significance to increase scientific landform reshaping,ecological restoration.In this paper,and the surrounding valley system in Pingshuo mining area as the research object,form,features extraction of valley lines,analysis of slope and channel changes around the valley in the erosion interaction analysis on spatial temporal evolution of the surrounding valley system in Pingshuo mining area.The main conclusions are as follows:(1)Quantifying the morphological features of gullies.Select the line height,slope gully morphological characteristics index,analysis of the changes of morphological characteristics of the gully region found that less than 5km Valley changes frequently,gully length and number increased overall.In the study area,the height difference of the valley line belongs to the 0-100 m range,and the length and the number of the negative elevation difference valley line increase.The average slope of valley line decreased,gully gully head at high slope,soil erosion quantity.The width to depth ratio of gullies increases with the accumulation of development time,and the valleys are mainly composed of gullies,gullies and depressions.(2)Statistics the slope characteristics of the dumping area,the opencast mine area,the well mining area,the industrial site and the original landform.The gully topography in natural condition is dominated by micro steep terrain with 5 degrees-10 degrees.The slope of open-pit mining area,well mining area,industrial site and dumping site mainly concentrates between 0 degrees-10 degrees,and the steep topography increases continuously.The slope of side slope and inner dumping soil slope of mine work slope is more than 15 degrees,and the slope of outer dumping soil slope is between 20 and-35 degrees.Batch discharge method in shaping the dump toless than 10 degrees,the micro flat and steep terrain,the industrial field in low-lying areas,located in the valley line.(3)The temporal and spatial variation of gully geomorphology after mining disturbance is analyzed.The area of river valley system factors from 1986 to 2013 in and around the area is the main impact of the open pit and dump pit,gully extension,channel for dump and shorten the.The valley line shows the characteristics of single line,abnormal direction and single line intersection,and the parallel valley line appears at the mine platform.(4)The composition,characteristics and ecological effects of gully system are defined.Pingshuo mining area and its surrounding area of gully system consists of the rill,ephemeral gully,gulch and clough.Rill,ephemeral gully and gully have many many adverse effects like great soil erosion.In the gulch and clough formation,habitat tend to complicated diversification,gulch clough have the ecological effects of biodiversity.