【作者】 郝云庆；

【导师】 李旭光；

【作者基本信息】 西南师范大学 ， 生态学， 2004， 硕士

【摘要】 巫溪县红池坝地区由于历史上开发强度和生态恢复措施的不同，使当地植被形成了从草本群落→灌木灌丛→林灌过渡带→日本落叶松(Larix daempferi)针叶纯林→华山松(Pinus armandii)针阔叶混交林→天然阔叶落叶林的一系列生态恢复演替阶段。本文采用以“空间代替时间”的方法对各个恢复阶段植被群落的动态特征，包括：物种组成结构、物种多样性、种群生态位、土壤营养元素含量变化的特征进行了研究。同时，在天然阔叶落叶林中选取一个最佳群落作为参照，运用群落高度、显著度、土壤肥力、盖度、组成结构和生物量6个指标为群落特征参数，对各个阶段群落恢复的程度进行了综合的评价。其研究结果如下： 1)物种多样性的变化总体上是随着群落演替的发展而逐步增加的。但当群落发展到成熟的顶级阶段时，多样性会随着一些先锋种的消失而有所下降；另外，林灌交替阶段会因“边缘效应”，物种多样性大幅增加。因此，物种多样性并非是衡量植被生态恢复效果的唯一指标。还应该进一步分析造成多样性高的原因，同时，必须把群落结构的稳定性和生态功能的发挥考虑在内。 2)华中山楂、四川樱桃、川滇海棠、漆树等乡土树种在几乎所有木本群落阶段(针叶纯林除外)都是优势种或共建种。乡土物种在生态恢复过程中更适于当地的生境，其繁殖和传播潜力更强。因此，应当充分发挥本地物种的巨大恢复潜力，尽可能以“乡土树种构建乡土森林”。 3)人工构建的群落(包括草本群落、针叶纯林和针阔混交林)其组成物种生态位配置差，生态位重叠大，造成群落组成结构不稳定。而由本地树种组成的天然林，生态位重叠小，种间关系协调，群落组成结构的稳定性更高。因此，在生态恢复工程的实施中应以本地物种作为培植对象，尽可能考虑以地带性植被作为恢复的最终目标。 4)土壤营养元素含量总体上是随着演替的进程逐渐提高的。但针叶林由于针叶较难分解，土壤综合肥力很低，甚至低于前期阶段;而由阔叶物种(包括灌木群落)组成的群落，土壤肥力普遍较高。因此，应重视通过调整物种组成，增加阔叶树种比例以增强森林的自肥能力。 5)植被恢复的策略是早期阶段以抢占空间、覆盖地面的对策为主，群落盖度恢复很快;中期阶段，林内光照环境改变，物种替代，恢复对策以物种组成成分的调整为主;后期则是生物量积累与组成结构调整并重。可见，恢复过程中盖度、组成成分、显著度总是先于生物量的恢复:而群落功能的恢复速度滞后于其结构的恢复。 6)植被自然恢复过程并非一定要经历每一个典型演替阶段，这要视气候条件、人为干扰强度或植被、土壤退化程度而定。该地植被演替可直接从林灌阶段向着原生阔叶林群落的方向发展。这样可以大大加快生态恢复的进程，提高生态恢复工程的效益。 以上研究旨在探讨该地区生态恢复过程中存在的问题，总结其成功的实践技术与经验，并提出相应的恢复措施，这是对于完善生态恢复理论的应用实践，同时，对于指导巫溪县及邻近地区的退化生态系统恢复与重建工作和水土流失的治理都有着重要的参考价值。更多还原

【Abstract】 Due to different exploitation intensity and ecological restoration measures used in Hongchiba region, Wuxi county, the vegetation have been formed a series of succession stages, i.e. herbaceous stage scrub-shrub stage-shrub-tree stage-pure Larix daempferi conifer forest stage-Pinus armandii needle broad-leaved mixed forest stage-natural deciduous broad-leaved forest. On the basis of substituting space for time, communities dynamic characteristics including composition and structure, species diversity, population niche, soil nutrient content were investigated. In the meanwhile, the best community that was picked out from natural deciduous broad-leaved forest was taken as contrast. And the hight, dominance, soil fertility, coverage, composition and biomass of the community were used as community characteristics parameters to comprehensively evaluate the restored degree of communities at different restoration stages. The results as following:i) Totally, species diversity increased gradually with the development of community succession. When community developed to climax stage, however, the species diversity would decrease attributing to the disappearance of some pioneer species. In addition, species diversity of the shrub-tree ecotone would increase swingingly, due to the "bundary effects". Thus, species diversity could not be regarded as a unique index for measuring the effect of vegetation ecological restoration. Moreover, the reasons resulted in the higher species diversity should be further discussed. Stability of community structures and its ecological function should also be considered simutaneously.ii) Some native spcies, eg. Crateagus wilsonii, Cerasus szechuanica, Malus prati, Toxicodendron verniciflua, are dominants and co-edificators in almost every woody communities. It indicated that the reproduction and spread ability of native species were stronger than those of artificial species. And the native species were more suitable for the native habitats during the process of ecological restoration. Native forest therefore should be built with native species. The powerful restoration potentiality of native species should be utilized more wildly in the process of ecological restoration and rehabilitation.iii) For artificial communities including herbaceous community, pure conifer and needle broad-leaved mixed forest, the poor niche configuration and serious niche overlap of component species made the composition structure of community be in an unstable state. Whereas, for the natural forest consisted of native species, the niche overlap was low and the interspecies relationship was harmonious. The composition structure of community thereby was more stable. Considering the fact, native species should be used as cultivation object and regional vegetation should be served as ultimate object during the process of ecological recovery and rehabilitation.IV) Soil nutrient contents increased with the succession progress generally. But for conifer community, since needle leaves decomposed very slowly, soil nutrient contents were rather low and even lower than those of former stages. On the contrary, natural communities consisted of broad-leaved species, including shrub community, commonly possessed high soil nutrient contents. Therefore, it should be emphasized to enhance the self-fertilization capability of forest by adjusting the species composition and increasing the proportion of native broad-leaved species.V) Occupying space and covering ground should be served as the main strategy in early stage of vegetation restoration, which would enable the community coverage to rehabilitate rapidly. In mid-stage, due to the change of light environment and the species substitution, component adjustment should be chose as the main strategy. In later stage, both biomass accumulation and component adjustment should be conducted as main strategy. It can be found that the restoration of coverage, component and dominance were always prior to that of biomass during the course of restoration. Meanwhile, t更多还原