Ecological Study of Vegetation Dynamics under Human Activity in the Eastern North American Cultural Region for Comparison with Japan

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Data collection involved sampling of the vegetation as many sites as possible across the region from Florida in the U. S. A. to Quebec in Canada and from the Atlantic Ocean inland to the Appalachian Mountains, a distance of about 3000km. From 1988 to 1990, natural and substitute vegetation were investigated by the method of Braun-Blanquet releves. These include salt-marsh vegetation in coastal Georgia, mangrove vegetation in Florida Peninsula, evergreen broad-leaved forests of Quercus virginiana on dry to mesic sites and Persea palustris Magnolia virginiana forests on wet sites and, decituous forests such as deciduous Quercus forests, Fagus grandifolia forest, Liriodendron forest, Carya forest on the lower mountain and alluvial area. On the higher mountains, subalpine conifer (Abies) forest, Betula forest, some shrub communities (such like Rhododendron comm. etc.) were surveyed. In the northernmost part of the east coast of the U. S. A. to Canada, peat bog vegetation was collected. Especially in this region, cer saccharum forest was surveyed. Some substitute vegetation was also sampled, including Palmetto Pinus forest, mantle communities with vines, trampled communities with Plantago etc. Total sampling plots were about 1500.There are no virgin forests in Eastern North America, since the U. S. A. does not have any tradition of shrine or temple forests comparable to Japan. Most flat areas are developed and changed to residences, cultivated fields, pastures, secondary forests, such as Pinus forests in the southeastern and coastal U. S. A., and Liquidamber forest. Pinus forests are spread more than before because of lightning and/or burning by human impact. No natural vegetation remain in the mountain and hill area, however, it is admired that the large trees of natural forest are remained and/or planted surroundings of residences, public buildings and/or in parks.