|
The flora of Belize is highly diverse by regional standards, given the country's small geographical extent. Situated on the Caribbean coast of northern Central America the flora and vegetation have been intimately intertwined with Belize's history. The nation itself grew out of British timber extraction activities from the 17th century onwards, at first for logwood (''Haematoxylum campechianum'') and later for mahogany (''Swietenia macrophylla''), fondly called "red gold" because of its high cost and was much sought after by European aristocracy. Central America generally is thought to have gained much of it characteristic flora during the "Great American interchange" during which time South American elements migrated north after the geological closure of the isthmus of Panama.〔Gentry, A.H. 1982. Neotropical floristic diversity: phytogeographical connections between Central and South America, Pleistocene climatic fluctuations, or an accident of the Andean orogeny? Annals of the Missouri Botanical Garden, 69, 557-593〕 Few Amazonian elements penetrate as far north as Belize and in species composition the forests of Belize are most similar to the forests of the Peten (Guatemala) and the Yucatán (Mexico).〔Brewer, S. et al. 2003 J. Biogeography 30: 1669- 1688〕 ==Vegetation types== The vegetation of Belize was first systematically surveyed in the 1930s.〔Standley, P.C. and Record, S.J. 1936. The forests and flora of British Honduras. Fieldiana, Bot. 12: 1-432〕 Recent mapping projects have employed the following principal terrestrial and coastal categories of native vegetation:〔(BERDS > Mapping )〕 * lowland broad-leaved forest. This is a diverse forest type in Belize, now greatly reduced in extent by clearance for agricultural land. It includes such tropical tree species as ''Simarouba glauca'', ''Calophyllum brasiliense'', ''Terminalia amazonia'' and ''Pterocarpus officinalis''. * lowland savanna. This is an important vegetation type in northern Belize, in which scattered trees occur in "short grass" (actually mainly sedges). Savanna is maintained as open vegetation by a combination of wet-season flooding, dry-season drought and fire. Typical trees include: ''Acoelorraphe wrightii'', ''Quercus oleoides'' and madre de cacao ''Gliricidia sepium''. * lowland pine forest or pine savanna (open forest mainly composed of ''Pinus caribaea var. hondurensis'' with shrubs such as the rough-leaved "sandpaper tree" (Curatella americana). * submontane pine forest (with ''Pinus ayacahuite'', ''Pinus oocarpa'' and ''Pinus rudis'' together with some broadleaved species) * submontane broadleaved forest. Characteristic vegetation of the Maya Mountain massif above 500m. Typical species include ''Podocarpus guatemalensis'', ''Swietenia macrophylla'', ''Terminalia amazonia'', ''Virola brachycarpa'', and the palm ''Astrocaryum mexicanum''. * mangrove and littoral forest. Ecologically important vegetation type of the coastal cayes. Several species of mangrove are involved including: red mangrove (''Rhizophora mangle''), black mangrove (''Avicennia germinans'') and white mangrove (''Laguncularia racemosa''). In addition the buttonwood (''Conocarpus erectus'') although not a true mangrove is often associated with mangroves in littoral forest. Also see the section on mangroves below. * seagrass beds. Sandy bays often have extensive mats of seagrass. There are several different types in Belize: turtle grass (''Thalassia testudinum'' in the Hydrocharitaceae), manatee seagrass (''Syringodium filiforme'' in the Cymodoceaceae), duckweed seagrasses (''Halodule'' spp in the Cymodoceaceae). * riparian shrubland. This is a mixed vegetation type, of shrubs and small trees with grasses and sedges, found along watercourses. Typical species include ''Schizolobium parahybum'' and ''Ceiba pentandra''. Loss of this habitat was one of the particular environmental concerns of building the Chalillo Dam on the Macal river. 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「Flora of Belize」の詳細全文を読む スポンサード リンク
|