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The Klamath Mountains ecoregion of Oregon and California lies inland of the Coast Range ecoregion, extending from the Umpqua Valley in the north to the Sacramento Valley in the south. It encompasses the highly dissected ridges, foothills, and valleys of the Klamath and Siskiyou Mountains. It corresponds to the Level III ecoregion designated by the United States Environmental Protection Agency (EPA) and to the Klamath-Siskiyou forests ecoregion designated by the World Wide Fund for Nature. The ecoregion was unglaciated during the Pleistocene epoch, when it served as a refuge for northern plant species. Its mix of granitic, sedimentary, metamorphic, and extrusive rocks contrasts with the predominantly volcanic rocks of the Cascades ecoregion to the northeast. The mild, subhumid climate of the region is characterized by a lengthy summer drought. It supports a mosaic of both northern Californian and Pacific Northwestern conifers and hardwoods. The Klamath Mountains ecoregion is a vast, well-protected region that is sparsely populated. While the Klamath Mountains do not have the charismatic megafauna that make other National Parks or vast wilderness areas attractive to visitation, the plant diversity offers an enjoyable hiking experience. ==Ecology== The ecoregion harbors rich biodiversity, with several distinct plant communities, including temperate rain forests, moist inland forests, oak forests and savannas, high elevation forests, and alpine grasslands. Thirty conifer species inhabit the region, including seven endemic species, making the region one of the richest coniferous forest regions of the world in species diversity. The region also has several edaphic plant communities, adapted to specific soil types, notably serpentine outcrops. Conifer species include Coast Douglas-fir ''(Pseudotsuga menziesii'' subsp. ''menziesii)'', Lawson's Cypress (also known as Port Orford Cedar, ''Chamaecyparis lawsoniana''), Ponderosa Pine ''(Pinus ponderosa)'', Sugar Pine ''(Pinus lambertiana)'', Mountain Hemlock ''(Tsuga mertensiana)'', White Fir ''(Abies concolor'' subsp. ''lowiana)'', Red Fir ''(A. magnifica'' subsp. ''shastensis)'', Weeping Spruce ''(Picea breweriana)'', Coast Redwood ''(Sequoia sempervirens)'', and Pacific Yew ''(Taxus brevifolia)''. These forests mark the northern extent of the range for California Buckeye. 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「Klamath Mountains (ecoregion)」の詳細全文を読む スポンサード リンク
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