集合种群竞争机制在庐山森林演替模拟中的应用

Application of meta-population competition mechanism in forest succession simulation of Mount Lushan

通过对森林植被群落的动态模拟,可以揭示森林植被的恢复过程和演替规律。本文将动物集合种群竞争模型引入森林演替模拟中,以庐山为研究区域选取10个优势乔木种进行了森林演替模拟。在MATLAB中分别对当前生境条件、生境破坏条件和生境恢复条件进行模拟,结合庐山森林演替动态曲线和各优势种对外界条件响应规律,总结了对不同物种续存的保护机制。结果表明:(1)庐山森林种群整体向常绿阔叶林方向演替,混生林中阔叶树占优势;(2)森林群落中的优势物种可分为3个等级:第一等级优势种对恶劣生态环境适应性强,但在生态环境得到保护时容易被低优势度物种侵占,应防止人工引进的外来物种对原有优势种造成过度侵占;第二等级优势种对生境变化敏感,生境严重破坏会造成这类物种灭绝,生境恢复能使之续存;第三等级优势种在生境恢复条件下也难以续存,应采取人工育林等措施进行保护。

Forest succession simulation can reveal the restoration process and succession patterns of forest vegetation. Vegetation succession simulation in natural reserve is an important theoretical basis for forest conservation. The result of traditional simulation is usually a time-series data,which is simulated under current ecological environment,hard for validation,and not adequate for the guidance of forest conservation. Therefore,an essential part of simulation is to know how human activities affect forest succession by considering ecological conditions as model variables,and applying the simulation model under different ecological conditions. This study introduced the meta-population theory into the forest succession simulation by taking Mount Lushan as a case study,and selected 10 dominant species for the simulation. MATLAB was used to simulate different conditions,i.e. current habitats,habitat destruction,and habitat restoration. Combining the area ratio curve of forest succession dynamics and the responses of 10 species to different conditions,this paper summarized the protection measures for different species. The results indicated that the overall succession for all forest populations trended towards evergreen broad-leaved forest,and broad-leaved trees were dominant in mixed forests. The dominant species in forest community could be divided into three levels：（ 1） The first-level species have strong adaptability to harsh ecological environment,but they are easy to be replaced by species with low dominance when habitats keep stable,and we should prevent artificial introduction of exotic species from excessively occupying the habitats of original dominant species;（ 2） The second-level species are sensitive to habitat change,and serious habitat damage will cause their extinction. However,they can survive under habitat restoration;（ 3） The third-level species have difficulty to survive even under habitat restoration,and artificial cultivation measures should be taken to protect these species.