我国喀斯特断陷盆地石漠化区植物群落构建机制研究

Plant Community Establishment Mechanism in Rocky Desertification Area of Karst Fault Basin in China

喀斯特断陷盆地是我国石漠化综合治理8大喀斯特类型中治理成效最低、治理难度最大的区域,面临石漠化严重、干旱频发、植被恢复难等突出问题。文中针对水分是影响喀斯特断陷盆地石漠化治理与植被恢复成效最关键的限制因素,综合分析了国内外水分梯度差异与植物群落构建机制研究动态与发展趋势;提出利用日趋成熟的水分脆弱性评价方法,通过建立基于耦合暴露度、敏感性及适应性的水资源脆弱性评价指标体系,以满足遥感影像分辨率和植物群落调查样地大小的评价单元进行水分脆弱性评估;在建立物种库-功能性状-生境特征数据库的基础上,提出基于功能性状差异进行喀斯特断陷盆地植物群落机制构建的研究方案。提出的研究方案有望解决喀斯特断陷盆地石漠化区水分梯度特征与分布格局、自然植物群落组配规律及其生境特征、水分梯度与生境要素对植物群落特征及功能性状组成的影响规律等关键科学问题,可为不同脆弱生态区植被恢复群落构建机制研究提供重要参考和借鉴。

The karst fault basin is the region where the rocky desertification control are challenged by the lowest effect and the greatest difficulty among the 8 karst types in China, and it faces serious problems including severe rocky desertification, frequent drought and difficult vegetation restoration. The paper comprehensively analyzes the research trends of water gradient differences and plant community establishment mechanisms at home and abroad in view of the fact that water is the most critical limiting factor affecting the rock desertification control and vegetation restoration effectiveness in the karst fault basin. The water vulnerability is evaluated using an increasingly mature water method of vulnerability assessment, with which a water vulnerability evaluation index system is established based on coupled exposure, sensitivity and adaptability, and the evaluation is made in the units which meet the resolution ratio of remote sensing image and the size of plant community investigation sampling plots. On the basis of a database of species bank-functional trait-habitat feature, a research scheme about establishing plant community mechanisms in karst fault basin is creatively proposed based on functional trait differences. The research scheme is expected to solve the key scientific issues including characteristics and distribution pattern of water gradient in rocky desertification area of karst fault basin, natural plant community assemblages and habitat characteristics and effects of water gradient and habitat elements on plant community characteristics and functional trait composition, which can also provide important references for the study of the mechanism of vegetation restoration communities establishment in different fragile ecological regions.