Constraints of seed bank species composition and water depth for restoring vegetation in the Florida Everglades, USA
Constraints of seed bank species composition and water depth for restoring vegetation in the Florida Everglades, USA
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DOI：
10.1046/j.1526-100x.2002.10115.x
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发表时间：
2002-03-01
影响因子：
3.2
通讯作者：
Garrett, PB
中科院分区：
文献类型：
--
作者：
Smith, SM;McCormick, PV;Garrett, PB
罗滕贝格野生动物管理区(RWMA)是美国佛罗里达州北部的大沼泽湿地，将进行水文恢复，以弥补人为缩短的水文周期。为了预测植被对即将到来的水文变化的响应，观察了1998年3月和9月三种不同水分状况下居民种子库的植物群落发展情况。湿润土壤的盖度、物种密度、苗木总密度以及兼性、兼性旱地和旱地指示种的百分比显著高于饱和土壤。淹水抑制了除香蒲以外的所有物种的萌发，香蒲在两种测定中都是从饱和土壤中出现的数量最多的物种。千金莲在饱和和潮湿条件下都有丰富的生长。化验季节影响物种密度和群落。在3月份的试验中，饱和土壤中兼性湿地物种的百分比增加了，但在9月份没有增加。相比之下，只有在9月份的化验中，专性水生植物的百分比在饱和条件下才更高。总的来说，化验群落与北部大沼泽地目前未受干扰的或历史悠久的湿地中的植被几乎没有相似之处。因此，RWMA种子库对恢复社区的发展几乎没有贡献。此外，复水可能会鼓励不受欢迎的水生植物的传播，如多明山水生植物。这项研究支持这样一种观点，即水文恢复必须伴随着一定程度的主动植被管理，不能被动地达到参考条件。
The Rotenberger Wildlife Management Area (RWMA) is a northern Everglades marsh, in Florida, U.S.A., that will undergo hydrologic restoration to remedy an artificially shortened hydroperiod. In an effort to predict vegetation responses to the impending changes in hydrology, plant community development from the resident seed bank was observed in response to three different moisture regimes in March and September 1998. Percent cover, species densities, total seedling densities, and percentages of facultative, facultative-upland, and upland indicator species were significantly higher in moist than in saturated soils. Flooding inhibited the germination of all species except Typha domingensis (cattail), which emerged in the highest numbers from saturated soils in both assays. Lythrum alatum (purple loosestrife) was abundant in both saturated and moist conditions. The season of assay affected species densities and the communities. Percent facultative-wetland species increased in saturated soils in the March assay but not in September. In contrast, percent obligate hydrophytes were higher in saturated conditions only in the September assay. In general the assay communities bore little resemblance to vegetation in currently undisturbed or historic wetlands of the northern Everglades. Consequently the RWMA seed bank will contribute little to the development of a restored community. Moreover, rehydration may encourage the spread of undesirable hydrophytes such as T. domingensis. This study supports the contention that hydrologic restoration must be accompanied by some level of active vegetation management and that the reference condition cannot be attained passively.