状态: 外来 入侵: 入侵 出现纪录: ???????? 来源: Dray Bennett & Center 2006; Dray et al. 2009 此地点的物种说明: Please visit this chronological interactive distribution map created by The Areawide Management and Evaluation of Melaleuca (TAME) to map the spread of melaleuca in Florida between 1993 and 2005; please see Early Detection and Distribution Mapping System for a current county distribution map (click on "melaleuca"). M. quinquenervia was first imported into Florida around the turn of the century as an ornamental tree and was planted widely in several different locations in Florida. These trees were sought as: (1) a landscape species; (2) a forestry crop that could grow on the edges of the Everglades; and (3) a useful tree for drainage projects and to reduce conditions favorable for disease-carrying insects (Gifford 1935, in Dray Bennett & Center 2006). In southern Florida extensive stands of melaleuca occur along the coasts and inland. The most extensive melaleuca stands are located near the sites of original introduction and in areas that have been severely altered by human activities (Munger 2005; Buckingham 2001). It is estimated that Melaleuca might have invaded as much as 610 000 hectares in southern Florida, especially in seasonally inundated parts of Miami-Dade, Broward and Monroe Counties where sawgrass marsh (dominated by Cladium jamaicense and Muhlenbergia capillaries var. filipes) is the main community type (Bodle et al. 1994, in Fuller 2005. (Note that the total area classified as pure melaleuca in a 1987 survey of south Florida was only 19 000 hectares or 47 000 acres). 此地点的管理信息: Biological control and integrated management programs have resulted in declines of M. quinquenervia in Florida. As a result of the Melaleuca Management Plan (see Integrated Management) almost 40 000 hectares or 100 000 acres of natural area have been cleared of melaleuca (Laroche 1999). Unfortunately, an almost equal expansion of melaleuca on privately held lands has occurred, resulting in no net loss of melaleuca (Laroche 1999). The greatest declines in melaleuca density have occurred in dry rather than seasonally flooded habitats. Please follow this link for more details on the management of melaleuca in Florida. 影响: 威胁濒危物种: South Florida encompasses the only region of the continental United States where temperate, subtropical and tropical floral elements coexist. This unique interface has produced about 65 endemic plant taxa, many of which are threatened due to habitat diminishment (Turner et al. 1998). There are concerns that M. quinquenervia invasions could further reduce populations of such endangered species as the Wood Stork (Mycteria americana) (Bancroft et al. 1992, in Turner et al. 1998) and the Florida Panther (Felis concolor coryi) (Grow 1984, in Turner et al. 1998). 改变林火机制: Massive seed dehiscence and release follows disturbances such as fire events. Once established, melaleuca is likely to attain and retain dominance on sites visited by frequent fire. March to June is typically considered wildfire season in southern Florida (Robbins & Myers 1992, in Munger 2005). 栖地改变: Dense monospecific stands of melaleuca displace vast areas of native plant species (Pratt et al. 2005). 竞争: Melalueca quinquenervia has proven to be a superior competitor to most native vegetation occurring in the organically rich soils of forested and sawgrass dominated wetlands that characterize the Florida Everglades (Pratt et al. 2005). 经济 /民生: Diamond et al. (1991, in Buckingham 2000) prepared a state economic impact statement in support of adding melaleuca to the Florida Prohibited Aquatic Plant List. It was consequently added to the list. 降低本地生物多样性: Melaleuca-dominated landscapes result in drastically reduced biodiversity. Infestations have been found to reduce above- and below-ground biodiversity by as much as 80% (Poraziska et al. 2007). Density declines of melaleuca, due to control techniques, coincided with two to four fold increases in plant species diversity in some areas (Rayamajhi et al. 2008b). Bancroft et al. (1992, in Laroche 1999) claims that the trend of increasing Melaleuca forest, along with formerly rare cattail (Typha dominguensis) populations in the water conservation areas of the Everglades, can be expected to degrade native wood stork (Mycteria americana) habitat. 最后修改 : 11/12/2009 3:08:18 p.m.
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