Western hardwood gallery forests are found across an extremely large, diverse geographical area that encompasses the Great Plains in the United States and Canada. Remnant forests of this type still exist in the "Prairie Peninsula," which historically projected an eastern finger into Ohio. The forests are restricted to floodplains of major rivers and are in sharp contrast to the surrounding prairie. The name "gallery" forest refers only to forests that form a corridor of trees along river systems in the region. Disturbances associated with flooding, such as water and ice scouring, as well as soil deposition, are required for the establishment of cottonwood and willow stands, pioneer species of this type. Today, the historic hydrology of all Great Plains rivers has drastically changed with the creation of dams and other flood-control measures. The western hardwood gallery forest has changed as well, with composition shifting from shade-intolerant species, such as cottonwood and willow, to shade-tolerant species, such as green ash. Consequently, there is little regeneration of this forest type.

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Note added at 2003-06-28 09:54:06 (GMT)
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savana arbórea aberta com florestas de galeria = open tree savanna/savannah with gallery forests

savana arbórea aberta = open tree savanna / savannah

com florestas de galeria = with gallery forests