Preliminary Evaluation Of The Priority Of Plant Communities For Conservation In Northwest Yunnan

Biodiversity lossing and ecological degradation is incredibly increasing in China, it is urgent to protect the bioviversity and environment. Because of the limitation of the conservation fund, systematic and scientific methodology for identifying the priority conservation areas or biotypes should be established. Ecosystem and plant community are important habitat for individual species, in order to protect individual species, community and ecosystem should be conserved. Northwest Yunnan is one of biodiversity hotspots in the world. However, the existing protection system is insufficient. It is urgent to identify thepriority plant communities for conservation.In this study, we used Analysis Hierarchical Process (AHP) to establish an assessment indicator system. Based on the data collection, we employed the assessment criteria follow a general ranking assignment methodology for qualitative indicators, and class grouping methodology for quantitative indicators. The weights of all levels and comprehensive weights of each indicator were defined by using expert consultation and hierarchical analysis methods. Then we identified the priority conservation plant communities in Northwest Yunnan by doing integrated evaluation.The main results are listed following:(1) In order to identify the priority of plant community conservation, we established an assessment indicator system, which included13indicators:①Maintain biodiversity:species richness, habitat diversity, No. of rare and endangered plant species, protection level of plant species, rarity of the community type, No. of endemic plant species and endemism of community type;②Ecological service function:water conservation function and soil and water conservation;③Ecological vulnerability:altitude, vertical stratification of community, distance to population centre and distance to road.(2) We employed the assessment criteria for each indicator.(3) The single-factor evaluation of the priority of plant communities indicates that:each vegetation subtypes got a score in indicator level, and been divided into different grades; we got the distribution of different priority of vegetation subtypes for conservation under the influence of single factor.(4) We sequenced the vegetation subtypes and got the distribution of different priority of vegetation subtypes for conservation according to the evaluation result in criterion levels.The evaluation results by using integrated index methodology show that:①Maintain biodiversity:two second grade, five third grade and six fourth grade;②Ecological service function:four first grade, one second grade, three third grade, three fourth grade and two general grade;③Ecological vulnerability:eleven third grade and two fourth grade.The evaluation results using ArcGIS9.3show that, area of each conservation grade:①Maintain biodiversity:second grade4841.28km2, third grade3104.64km2, fourth grade49739.04km2;②Ecological service function:first grade2430.72km2, second grade128.16km2, third grade38907.36km2, fourth grade15360.48km2, general grade858.24km2;③Ecological vulnerability:first grade40.32km2, second grade1848.96km2, third grade24209.28km2, fourth grade31586.40km2.(5) We sequenced the vegetation subtypes and got the distribution of different priority of vegetation subtypes for conservation according to the evaluation result in target levels.Integrated evaluation result of target level:two second grade and eleven third grade; Integrated evaluation result of target level:second grade1216.80km, third grade44543.52km2, fourth grade11924.64km2.