Study On Evolution Of Soil Erosion In Qingdao Based On RS And GIS

Soil erosion has become the global hot topic with the development of social economy. The existence of soil erosion has aggravated the contradictions of population, resource, environment and development, caused plundering type management of the natural resources. Qingdao is in North China, its south, middle and north mountainous area is the relatively serious area of soil erosion. It has very important meanings in controlling soil erosion and constructing eco-environment to carry on soil erosion evolution.Based on the soil erosion and landscape ecology theory, the paper takes combination of quantitative research and qualitative analysis as a method, using remote sensing (RS) and geographic information systems (GIS) technology, gets the soil erosion data through the interpretation of Qingdao city in different times. Then divides soil erosion's type and intensity, masters and monitors different types of soil erosion occurred in quantity and regional spatial distribution of soil erosion characteristics and its evolution. Finally explores the strategies of prevention and control soil erosion to achieve regional sustainable development.The main thesis and conclusion of the study are as follows:(1)The paper appraises the present situation of soil erosion in Qingdao and divides soil erosion's type and intensity, sets up soil erosion database by using modern technological means, such as Remote Sensing and Geographical Information System, etc.(2)The paper using the principle of temporal and spatial variation of soil erosion model for different periods of time in space superimposed layers, cross-classification to study the dynamic changes of various intensities and types of soil erosion in the past 15 years (1990-2005), the area change and the average annual change rate, and compare the change processes of soil erosion in the typical district of Qingdao according to the administrative divisions. Studies have shown that 15 years of soil erosion in Qingdao the overall situation had improved, to reduce soil erosion area of 640.76 km2, an average annual reduction of 42.72km2.The reduction of soil erosion had a process of slow changes after the quick, soil erosion intensity of the conversion between the types tend to weaken, but an average mining erosion rate of change increases significantly should be attention.(3)By drawing support of ArcGIS, the paper extracts stratified soil erosion grid database and gets the maps of spatial pattern of soil erosion intensity changes in distribution. Using the map information theory, the paper reclassifies and integrates the map unit of soil erosion in different times, extracts the information of soil erosion in the conversion between the types, and by constructing the soil erosion index, the paper analyzes changes characteristics of soil erosion spatial pattern in different regions. Through analysis, the distribution of soil erosion is in both increased and decreased, but on the whole, the extent of soil erosion is weaken. The characteristic of concentrated lace into fragmented distribution has showed the comprehensive management of small watershed effect and better ecological recovery capabilities of forest, grassland.(4)The paper gets the spatial distribution of different land use areas'soil erosion index with the method of spatial overlay analysis on dynamic data of land use and soil erosion intensity data. It can be seen that the evolution of soil erosion intensity and changes in land-use types are interrelated. Their changes are not in one direction, but in volatility. Therefore, people should optimize the structure of land use and select a reasonable land use.(5)Starting from the landscape view, using the landscape ecology approach, the paper gives an analysis on the structure changes of soil erosion's landscape from the landscape types, patch characteristics, etc.. The paper selects the landscape diversity index, landscape dominance index, etc. to analyze the evolution characteristics of landscape pattern.The findings indicate that the cities construction and the humanity activity are the main causes of the Qingdao landscape space pattern change.(6) The paper analyzes influencing factors of the changes in soil erosion, predicates its trend according to the way of average growth coefficient, and puts forward several corresponding measures to prevent and cure soil erosion.