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Rangelands are grasslands, shrublands, woodlands, wetlands, and deserts that are grazed by domestic livestock or wild animals. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include forests lacking grazable understory vegetation, barren desert, farmland, or land covered by solid rock, concrete and/or glaciers. Rangelands are distinguished from pasture lands because they grow primarily native vegetation, rather than plants established by humans. Rangelands are also managed principally with practices such as managed livestock grazing and prescribed fire rather than more intensive agricultural practices of seeding, irrigation, and the use of fertilizers. Grazing is an important use of rangelands but the term "rangeland" is not synonymous with "grazinglands". Livestock grazing can be used to manage rangelands by harvesting forage to produce livestock, changing plant composition or reducing fuel loads. Fire is also an important regulator of range vegetation, whether set by humans or resulting from lightning. Fires tend to reduce the abundance of woody plants and promote herbaceous plants including grasses, forbs, and grass-like plants. The suppression or reduction of periodic wildfires from desert shrublands, savannas, or woodlands frequently invites the dominance of trees and shrubs to the near exclusion of grasses and forbs. ==Types of rangeland== The United States Environmental Protection Agency defines rangeland as "lands on which the native vegetation (climax or natural potential plant community) is predominantly grasses, grass-like plants, forbs, or shrubs suitable for grazing or browsing use."〔(【引用サイトリンク】url=http://www.epa.gov/agriculture/anprgidx.html )〕 The EPA classifies natural grassland and savannas as rangeland, and in some cases includes wetlands, deserts, tundra, and "certain forb and shrub communities."〔 The primary difference between rangeland and pasture is management; rangelands tend to have natural vegetation along with a few introduced plant species, but all managed by grazing, while pastures have forage that is adapted for livestock and managed, by seeding, mowing, fertilization and irrigation.〔 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「rangeland」の詳細全文を読む スポンサード リンク
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