Abstract:

Based on survey data of Yarlung Zangbo Grand Canyon National Nature Reserve,seven evaluation indices,including diversity,rareness,representativeness,naturalness,spatial natural suitable areas,vulnerability,and human impact,were chosen as the 1st level indices. Some indices of the 1st level were comprised of the 2nd level and the 3rd level indices. With those indices, a model of hierarchy structure of the ecological evaluation was established. A value of each index and its weight were determined by analytical hierarchy process(AHP) method from four respects of ecological function,including conservation of diversity,improvement of landscape ecological states,value of education and scientific research,value of ecotourism. The result of evaluation showed that the conditionality of the conservation of diversity was strongest, the improvement of landscape ecological states took second place, and the value of ecotourism was weakest. As for the contribution of indices level to object level, diversity provided the greatest contribution, followed by rareness, naturalness and representativeness, and then human threat, while the contribution of fragility was weakest. The composite evaluation index(CEI)was figured out as 0.945 1, suggesting that the ecological quality of the Yarlung Zangbo Grand Canyon National Nature Reserve would be very good,and the conservation value would be extremely high.

Key words: analytical hierarchy process, ecological evaluation, nature reserve, Yarlung Zangbo Grand Canyon