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Shrubland, scrubland, scrub or brush is a plant community characterised by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing. Shrubland may be unsuitable for human habitation because of the danger of fire. The term "shrubland" was first coined in 1903.〔Merriam-Webster's Collegiate Dictionary, 11th Edition (2003).〕 Shrubland species generally show a wide range of adaptations to fire, such as heavy seed production, lignotubers, and fire-induced germination. == Botanical structural form == In botany and ecology a shrub is defined as a much-branched woody plant fewer than 8 m high and usually with many stems. Tall shrubs are mostly 2–8 m high; small shrubs 1–2 m high: subshrubs less than 1 m high.〔''Flora of New South Wales'', Vol.4 ed. Gwen J. Harden, Royal Botanic Gardens, Sydney ISBN 0-86840-188-9〕 A descriptive system widely adopted in Australia to describe different types of vegetation is based on structural characteristics based on plant life-form, plus the height and foliage cover of the tallest stratum or dominant species.〔Costermans, L. F. (1993) ''Native trees and shrubs of South-Eastern Australia''. rev. ed. ISBN 0-947116-76-1〕 For shrubs 2–8 m high the following structural forms result: * dense foliage cover (70–100%) — closed-scrub * mid-dense foliage cover (30–70%) — open-scrub * sparse foliage cover (10–30%) — tall shrubland * very sparse foliage cover (<10%) — tall open shrubland For shrubs <2 m high the following structural forms result: * dense foliage cover (70–100%) — closed-heath * mid-dense foliage cover (30–70%) — open-heath * sparse foliage cover (10–30%) — low shrubland * very sparse foliage cover (<10%) — low open shrubland 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「shrubland」の詳細全文を読む スポンサード リンク
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