The world's deciduous forests encompass a variety of landforms.
Deciduous forests are those dominated by trees that lose their foliage for part of the year, whether in response to hard winters or dry seasons. Evergreen trees may indeed be a component of such ecosystems, but are usually scattered or limited in distribution. The deciduous forest may be thought as both a biome -- one of the world's major vegetation communities -- and, more broadly, as an ecological landscape in association with the landforms that underlie it.
Topographic Context
Exceedingly rich deciduous forests blanket lower and middle elevations of the southern Appalachians.
In both the temperate and subtropical zones of the world, numerous kinds of large-scale landforms support deciduous forests. In eastern North America, for example, deciduous forests blanket plains, hills and mountains alike. The Appalachian mountains support extensive examples; those of the Southern Appalachians, such as in the Great Smoky Mountains of Tennessee and North Carolina, are among the richest temperate woodlands in the world. At the highest elevations of the Appalachians, roughly over 5,000 feet along much of the range, the deciduous forest grades into conifer communities that have much in common with the taiga, or boreal forest, of northern North America. Associations of Indian-laurel, sal, jambul and other species help comprise the moist deciduous forests that blanket the foothills of the Eastern Ghats mountains and Satpura range in northeastern India, roamed by tigers, wolves, gaur and other large mammals that have become exceedingly rare in much of the country.
Swamps
Bald-cypresses are deciduous conifers that define many bottomland swamps of the South.
Large bottomland swamps are common landforms in the forests of eastern and southern North America, forming their own unique deciduous ecosystems in poorly-drained areas, notably the floodplains of big rivers. Rivers create floodplains through regular overtopping of their banks, depositing rich sediments in the low valley shouldering their usual channels. Some of the trees in bottomland swamps, such as water tupelo, sweetgum and the deciduous conifer called bald-cypress, may grow to immense proportions.
Glacial Landforms
The Great Lakes occupy glacially-scoured basins.
During the last Ice Age, continental glaciers generated at high latitudes extended southward across the Northern Hemisphere. In North America, large swaths of the northern portions of the eastern deciduous forest experienced glaciation, including much of the Central Lowlands and a portion of the Appalachian plateaus. Broad-leaved woods of oak, maple, basswood and beech in southern Wisconsin, for example, drape subdued glacial hills and ridges called drumlins, kames, moraines and eskers. The Great Lakes along the U.S.-Canada border, partly in the deciduous-forest realm, occupy ancient drainage basins greatly enlarged by glaciation.
Small-Scale Landforms
On a micro-scale, a great diversity of landforms exist within a deciduous-forest biome. The decomposition of felled trees creates a suite of landscape features, like tip-up mounds. These are low humps marking the position of a decayed uprooted trunk and rootstock, often bordering a hollow in which the living tree stood. Another glacially-derived landform on a smaller-scale than moraines or lakes is the glacial erratic: a huge, isolate boulder transported far from its point of origin by the moving ice body. Such striking rock masses loom from groundcover carpets in the woods, testament to the immense power and influence of the continental glaciers.
Tags: deciduous forests, North America, bottomland swamps, deciduous forest, continental glaciers, deciduous forests blanket
