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An invasive species is a plant, fungus, or animal species that is not native to a specific location (an introduced species), and which has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health.〔("Definition of terms" ), Non-native Species Secretariat, accessed August 31, 2014.〕 One study pointed out widely divergent perceptions of the criteria for invasive species among researchers (p. 135) and concerns with the subjectivity of the term "invasive" (p. 136).〔 Some of the alternate usages of the term are below: *The term as most often used applies to introduced species (also called "non-indigenous" or "non-native") that adversely affect the habitats and bioregions they invade economically, environmentally, or ecologically. Such invasive species may be either plants or animals and may disrupt by dominating a region, wilderness areas, particular habitats, or wildland-urban interface land from loss of natural controls (such as predators or herbivores). This includes non-native labeled as exotic pest plants and invasive exotics growing in native plant communities.〔Exotic Pest Plant Council. '(Exotic Pest Plants of Greatest Ecological Concern in California )' accessed 4/10/2010.〕 It has been used in this sense by government organizations〔(September 21, 2006). (National Invasive Species Information Center - What is an Invasive Species? ). ''United States Department of Agriculture: National Agriculture Library''. Retrieved on September 1, 2007.〕 as well as conservation groups such as the International Union for Conservation of Nature (IUCN) and the California Native Plant Society.〔 The European Union defines "Invasive Alien Species" as those that are, firstly, outside their natural distribution area, and secondly, threaten biological diversity.〔(【引用サイトリンク】title=Communication From The Commission To The Council, The European Parliament, The European Economic And Social Committee And The Committee Of The Regions Towards An EU Strategy On InvasFpollive Species )〕 It is also used by land managers, botanists, researchers, horticulturalists, conservationists, and the public for noxious weeds.〔(Exotic Pest Plant Council ). p. 1. accessed 4/10/2010.〕 The kudzu vine (''Pueraria lobata''), Andean Pampas grass (''Cortaderia jubata''), and yellow starthistle (''Centaurea solstitialis'') are examples. *An alternate usage broadens the term to include indigenous or "native" species along with ''non-native'' species, that have colonized natural areas (p. 136).〔 Deer are an example, considered to be overpopulating their native zones and adjacent suburban gardens, by some in the Northeastern and Pacific Coast regions of the United States. *Sometimes the term is used to describe a non-native or introduced species that has become widespread (p. 136).〔 However, not every introduced species has adverse effects on the environment. A nonadverse example is the common goldfish (''Carassius auratus''), which is found throughout the United States, but rarely achieves high densities (p. 136).〔 ==Causes== Scientists include species- and ecosystem factors among the mechanisms that when combined, establish invasiveness in a newly introduced species. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「invasive species」の詳細全文を読む スポンサード リンク
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