Comprehensive Quantitative Evaluation On The Ecological Impact Of The West Of Taijin Expressway On Local Environment

The construction of expressway was developing very fast. On one hand, it increased the pace of economical development, on the other hand, it had some negative effect on the local environment. The environmental impact of expressway evaluation using some ecological methods in the decision-milking phase of expressway design and construction could find the problem in time and take measures immediately which could decrease and avoid the negative impact on region ecological environment. Based on the Press—Status-Response model, this paper took the landscape pattern, ecological footprint and green equivalent ratio into consideration on the evaluation of the region 200 meters away from the mainline road.1. The lose of habitat, corridor effect, fragmentation caused by the expressway can change the landscape pattern. Comparing the index, we find that the number of patch increase from 913 to 1068, the patch density changed from 162.9591 to 190.6247 and the landscape shape index varied from 29.5602 to 28.0201. All the changes illuminated that the express construction caused the region more complex and fragment.2. The construction of expressway meant reduction of biological capacity in terms of the occupy of the fertile land. The ecological deficit increased from 0.2560hm~2/cap to 0.6922hm~2/cap. In another word, 1 km expressway constructions would increase the ecological deficit by 0.0055hm~2/cap. The structure of Ecological Footprint demand was obviously changed after the highway finished according to our analysis result. The main demand from EF was fossil energy land instead of arable land, which was the main reason to increase the ecological deficit.3. The highway project damaged the roadside vegetation seriously. The green equivalent ratio method considered not only the green land area, but also the ecological function of the green land. This index made the calculation results easier to compare in terms of total consideration. The analysis result illuminated that the regionlost 271.278hm in green equivalent. The virescence task could compensate187.882hm2 in green equivalent after the construction, which ranking the rate of 69%in compensation of green land lost.4. In order to get a final result, a fuzzy mathematic way was used to sum different results into one figure. Based on the range of variation, the weight and the standard block was calculated. By multiplying subjection matrix, a assessment matrix and a final score were calculated to measure the result. The final score: was 64.03 in this evaluation which meant that the express way had negative effect in ecological environment but it was under the safe range condition. If the ecologcical construction and recovery of the green land continue, the negative impact can be decreased further.