Analysis On Landscape Change And Soil & Water Conservation Of Harbin City

Harbin is located in the center of southern Heilongjiang Province, on the east of Songnen Plain. Covering 53,000 square kilometers, Harbin has jurisdiction over eight districts and ten counties. Urban areas of Harbin and Shuangcheng are flat, low-lying while eastern parts are mountainous, with Xiaoxing'anling in the north. Songhua River flowing through its central part and low mountains being scattered around, rivers and vast plains mainly cover the area. The city is one of the most severe soil erosion areas in Heilongjiang Province, which covers 2.2 million square kilometers, accounting for 16.3%of the province's soil erosion area and 41.2% of the total land area.Structure, function and process are the core of landscape ecology. The interaction of landscape patterns and ecological processes is the focus of landscape ecology. With population growth and socio-economic development, landscape structure and function have also taken a corresponding change, though, the shape, area,volume and space combination of landscape patches are closely related with species distribution, soil erosion and other ecological processes,So by studying the use of landscape pattern will help not only in prodding the relationship between the landscape pattern and nature, ecology and social economic activity but in the rational use of land resources and soil erosion control.The research,based on TM remote sensing image data, coupled with applications of GIS software Arc view and landscape pattern analysis software Fragstatsv3.3 of Oregon State University,will analyze the characteristics of Harbin landscape spatial pattern of land use in the patch and landscape level, the research unit under the jurisdiction of the range, from the aspect of patch area, patch number, patch density, edge density, landscape fractal dimension, combination index, Shannon diversity index and evenness index, etc. And based on landscape analysis, we selected two small watersheds in different areas fewer than two directions in ecological restoration of soil and water conservation for contrast and the results are as follows.1) The main part of the area under study is arable land, which is always maintained at 60% or more, and shows a trend of outward expansion, characteristic of agro-ecosystems, other landscapes following by are unused land, grassland, forest land, construction land and waters. As arable land, grassland and water area increased, woodland, construction land and unused land decreased. Particularly woodland and unused land (mainly swamp) land transferring to cultivated land are the most prominent. In composition of landscape types of land use, plain dry land occupy absolute position, the higher proportion of cultivated area and connectivity determine its status as the landscape matrix, illustrating that agriculture remaining play an important role in economic development. 2) The patch density analysis shows that a large number of rural settlements are scattered, highly fragmented, widely distributed in landscape, and affects a variety of other creatures' survival in landscape. Edge density, fractal dimension and connectivity analysis showed that the patch edge and geometry of cultivated land is relatively complex, with high combined degree; while forest patch edges and geometric shapes is simple, with higher combination and better connectivity.3) In study area, fragmentation index of grassland, water, and construction land decreased slightly or flat in landscape level, while arable land, forest land and unused land increased, especially farmland index which increased considerably, concentrated reaction the changes of cultivated area and pattern significantly affected the various land use landscape in the entire basin, farmland has closer relationship with other types of land use and landscape, while reflecting strong influence of of human activities on landscapes stability and sustainable development.4) Water, marsh area is reduced seriously, so as the hard-used land as the development and application of new technologies, and land-use converges to landscape elements of plain paddy field.5) In the study area, while the number of patches, degree of landscape division, separation, SPLIT index and other index increasing, the mean patch size MPS, distributed and parallel index IJI, the effective grain size and Shannon diversity index MESH SHDI, Simpson's diversity index SIEI and polymerization degree AI will decrease, indicating that the actual changes in the landscape, the changing trends play a negative domain to ecosystem functions throughout the region. Rapid increase in farmland landscape has an important role in the landscape pattern diversification; pattern changes of the basin had a negative impact on regional ecological environment and society.6) Interference of natural geographical and human activities resulted in land landscape patterns of small watershed. Adjusting the small watershed landscape pattern and improving the diversity of landscape, creating a multi-level structure in the space can take full advantage of the heterogeneity of environmental resources, and form new ecosystem structure, can enhance the ecological system stability.7) Taking different ecological restoration, two small watershed ecosystems stabilized and landscape pattern changed. The aim of ecological restoration and soil and water conservation can't be reached just taking the measures of fencing and closing hillsides to facilitate afforestation. Ecological restoration is a slow process; it can not bring better ecological benefit and economic benefit in a short time. However, we can take measures of artifical to accelerate ecological restoration and soil and water conservation.8) After the implementation of ecological restoration, there is no obvious advantage type of landscape, and patch types are more evenly distributed across the landscape, watershed eco-tone features of the landscape are more obvious, and eco-system is more stable.9) Compared to key soil erosion control with all anthropogenic interference ecological restoration, the soil erosion area, through policy and strengthened management, supplemented by artificial promotion of measures eliminated unreasonable disturbance, promoted the inherent regenerative capacity of nature to maximum, protected and improved the structure, landscapes and features of damaged ecosystems, thus establishing and maintaining an ecological system compatible with natural conditions, and coordination of economic and social sustainable development, which is relatively stable and healthily developed.10) Harbin soil and water conservation in future development pattern should implement conservation priority strategy,comprehensive control strategy and science and technology support strategy on the base of constructing completely scientific soil erosion prevention and control system. And pay more attention on project implementation development; adhere to the water system division project; combine soil and water loss control and ecological restoration with key harness in sloping farmland ensure food safety. And protect water and soil resources and ecological environment according to law.