| The ecological environment is the basic conditions for human survival and development. It is basic principle for our country’s modernization to achieve sustainable development. With the rapid economic growth, the pace of development of China’s highway construction and transportation accelerated, in promoting the improvement of human society, meanwhile, will inevitably lead to many ecological problems. Due to constraints of the majority of projects by road line selection and construction costs and other issues, ignored the huge threat of highway ecosystem, which caused cumulative change to the landscape pattern, vegetation productivity, water environment, habit quality, along with landscape ecological quality. Therefore, a comprehensive and systematic analysis of the road to the ecological environment influence, as far as possible to prevent and reduce its negative influence, is an urgent task for the construction of ecological civilization in the transportation industry. In this paper, using GIS technology, based on the analysis of related research at home and abroad, analyzed the ecological effects of road construction on the surrounding landscape, and provide a scientific basis for regional environmental protection and management. The main work of this paper is as follows:1) This thesis takes the 2010 forest resources inventory vector data of Jiangle County as source data, using ArcGIS and Fragstats software, dividing Forest landscape types from land type and tree species composition, Selection of landscape patch type indexes, shape index and heterogeneity index, quantitative analysis of fractal characteristics of Jiangle County, forest landscape pattern and landscape structure with fractal theory. The results show that the average area, the percentage of landscape, the largest patch index, the edge density and aggregation index were respectively 551.776 hm2,81.458%,39.980%,33.770 m/hm2,99.993, larger than other forest landscape types, illustration the dominance forest, the natural connectivity and higher rates on the contribution of the whole landscape; coniferous forest landscape percentage, number of patches, landscape shape index, edge length, patch density and edge density is respectively 26.853%,2180,87.324,8461840 m,0.969,37.627 m/hm2, explanation the higher of proportion of the total area, landscape fragmentation degree and the complex degree of the landscape space structure; The percentage of timber forest landscape, the largest patch index, the edge length, edge density and perimeter area fractal dimension is respectively 58.202%,15.268%,9436965 m, 41.963 m/hm2,1.253, showing the high of advantage degree of timber forest and the low stability; The average patch area of natural forest, the percentage of landscape, the largest patch with high index as 85.679 hm2,53.452%,15.745, Less plaque density, The landscape connectivity of natural forest, the dominant position of the large plaque was higher and the degree of fragmentation was lower.2) This paper aims to reveal the effects of topographical factors on forest landscape pattern in the upstream district of Minjiang River. Taking Jiangle county as research area, quantitative analysis was carried out for forest landscape pattern changes under different topographical factors, such as landform, slope and aspect. The results show that low mountain and steep slope was distributed widely in the study area, accounting for 49.81% and 62.34% of the woodland, respectively. The values of landscape indices, such as class area, landscape shape index and Shannon’s diversity index firstly increased and then decreased with the increasing of the altitudes and the slopes. But largest patch index and connectivity index decreased with the increasing of the altitudes and the slopes firstly, then increased. In terms of different categories of forest landscapes, the coniferous forest was mainly distributed in the low mountain, steep slope and half-sunny slope, while the bamboo pure forest concentrated in the middle mountain area with high altitude, the forest landscape pattern varied with different terrain factors, with the slope being among the most impacted terrain factor followed by physiognomy and aspect.3) The paper is based on forest resource inventory vector and the vector of traffic map of 2010 Jiangle County as the basic data, according to species composition of forest landscape classification, selection the same length of the highway, county and township roads, landscape element information of areas within 100 m,100-200 m,200-500 m,500-1000 m and 1000-2000 m distance from different classes of roads was obtained respectively using method of buffer analysis by ArcGIS. Thus, gradient changes of landscape patterns were analyzed and compared among different buffers of roads, with landscape metrics calculated by Fragstats program. The results showed that provincial road had the largest influence on the non-forest land, while county and village road had the largest influence on the coniferous plantation forest. With higher connectivity in landscape, the fragmentation degree in provincial road sides was lower than that in county and village road sides. Moreover, the values of landscape indices, such as patch type, total edge and evenness increased with the increase of road buffer distance, while the opposite for the trend of landscape fragmentation and agglomeration. Landscape structure tended to be more affected in area less than 500m distance from road and county and village road side. Differentiates of landscape structure among different grades of roads mainly existed within 200 m of the road buffer zone.4) Finally, the paper discusses the different grade of Road influence domain forest landscape ecological effects with the topography, slope and slope to the three topographic factor changes the rules. Selected for the same length of highway county road, township road three different grades of road, according to the tree species composition, the landscape elements were divided into 1000 m types, the degree of landscape fragmentation, the slope and the slope downward landscape, quantitative description of the impact of terrain factors and road construction on the landscape. Results show that the road on both sides of the terrain factors influence the highest landscape types is the coniferous pure forest, followed by economic forest. Terrain is the biggest influence on landscape pattern factor is slope, followed by topography, and the influence of the slope to the smaller. Township Road influence on landscape pattern is the most serious, followed by Provincial Road, then county. |
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