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The environmental effect of degraded ecosystem‘ s vegetation restoration in low subtropical China was studied. Results indicated that the vegetation recovery on degraded lands slgnificantly ameliorates surrounding environment, increases species diversity, improves soil structure, raises soil fertility, enhances productivity, and promotes regional agricultural production and social economic development dramatically. Through the combining engineering and biological measures, the restoration of degraded ecosystem in low subtropical area is possible and economical. The restoration experience in Xiaoliang, Wnhua and other sites are valuable for other degraded subtropical area was introduced. 相似文献
253.
澳门植被恢复过程土坑法的效应机制探讨 总被引:1,自引:0,他引:1
在澳门凼仔岛和路环岛两个离岛的植被成功恢复过程中,土坑法这一技术的应用起到了很好的作用。对土坑法在澳门植被恢复过程中的作用机制及其应用价值进行了初步的研究。对土坑区和无坑区的土壤理化性质测定的结果显示,土坑区土壤容重小于无坑区土壤容重,土坑区土壤含水量、土壤pH、有机质、全N等指标均比无坑区要高;对群落优势种台湾相思(Acacia confusa)生物特征的测量也发现,土坑区的植物生长优于无坑区。这表明土坑区的土壤物理结构和土壤肥力都有所改善,也有助于植被的生长。以上研究结果表明,土坑法是一项行之有效的植被恢复技术,对植被的恢复起到促进作用,可以在澳门进一步的生态恢复中继续应用并加以推广。 相似文献
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用马尔柯夫模型预测马尾松低效林改造恢复过程 总被引:5,自引:0,他引:5
运用马尔柯夫模型对四川盆地马尾松低效林改造恢复过程中林分各层次盖度、多样性指数和灌木层物种组成的变化趋势进行了预测.结果表明:马尔柯夫模型可适用于退化森林生态系统人工恢复重建过程的研究;四川盆地马尾松低效林可以自然恢复,但采用封育补植措施则能加快恢复进程.对马尔柯夫模型及预测结果进行了讨论. 相似文献
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Motivations for the Restoration of Ecosystems 总被引:5,自引:0,他引:5
Abstract: The reasons ecosystems should be restored are numerous, disparate, generally understated, and commonly underappreciated. We offer a typology in which these reasons—or motivations—are ordered among five rationales: technocratic, biotic, heuristic, idealistic, and pragmatic. The technocratic rationale encompasses restoration that is conducted by government agencies or other large organizations to satisfy specific institutional missions and mandates. The biotic rationale for restoration is to recover lost aspects of local biodiversity. The heuristic rationale attempts to elicit or demonstrate ecological principles and biotic expressions. The idealistic rationale consists of personal and cultural expressions of concern or atonement for environmental degradation, reengagement with nature, and/or spiritual fulfillment. The pragmatic rationale seeks to recover or repair ecosystems for their capacity to provide a broad array of natural services and products upon which human economies depend and to counteract extremes in climate caused by ecosystem loss. We propose that technocratic restoration, as currently conceived and practiced, is too narrow in scope and should be broadened to include the pragmatic rationale whose overarching importance is just beginning to be recognized. We suggest that technocratic restoration is too authoritarian, that idealistic restoration is overly restricted by lack of administrative strengths, and that a melding of the two approaches would benefit both. Three recent examples are given of restoration that blends the technocratic, idealistic, and pragmatic rationales and demonstrates the potential for a more unified approach. The biotic and heuristic rationales can be satisfied within the contexts of the other rationales. 相似文献
259.
Evaluating Effects of Habitat Loss and Land-Use Continuity on Ant Species Richness in Seminatural Grassland Remnants 总被引:2,自引:0,他引:2
Abstract: Seminatural grasslands in Europe are susceptible to habitat destruction and fragmentation that result in negative effects on biodiversity because of increased isolation and area effects on extinction rate. However, even small habitat patches of seminatural grasslands might be of value for conservation and restoration of species richness in a landscape with a long history of management, which has been argued to lead to high species richness. We tested whether ant communities have been negatively affected by habitat loss and increased isolation of seminatural grasslands during the twentieth century. We examined species richness and community composition in seminatural grasslands of different size in a mosaic landscape in Central Sweden. Grasslands managed continuously over centuries harbored species-rich and ecologically diverse ant communities. Grassland remnant size had no effect on ant species richness. Small grassland remnants did not harbor a nested subset of the ant species of larger habitats. Community composition of ants was mainly affected by habitat conditions. Our results suggest that the abandonment of traditional land use and the encroachment of trees, rather than the effects of fragmentation, are important for species composition in seminatural grasslands. Our results highlight the importance of considering land-use continuity and dispersal ability of the focal organisms when examining the effects of habitat loss and fragmentation on biodiversity. Landscape history should be considered in conservation programs focusing on effects of land-use change. 相似文献
260.