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Land Use Forests and Rangeland
Land Use Forests and Rangeland
16
Environmental Studies
12th Grade
05/02/2006

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Term
Old-growth forest or frontier forests
Definition
These forests cover a large enough area & have been undisturbed by human activities for a long enough time so that trees can live out a natural life cycle & ecological processes can occur in relatively normal fashion. The trees do not have to be thousands of years old.
Term
% of forest & land types
Definition
32% forest & woodlands, 31% other, 26% rangle & pastureland, 11% cropland.
Most forest is closed canopy (tree crowns spread over 20% or more of the ground) = good potential for commercial timber. Open canopy or woodland = tree crowns cover less than 20% of the ground.
Term
% closed canopy by country
Definition
N.America = 26%
Russian Federation = 24%
S. America = 20%
Asia = 13%
Africa = 7%
Europe = 4%
Oceania = 3%
Term
Fuelwood
Definition
Accounts for just over 1/2 of all wood harvested worldwide.
Term
Forest management
Definition
Planning for sustainable harvests.
Term
Monoculture forestry
Definition
Large plantations of single-species, single-use, intensive cropping.
Term
milpa or swidden agriculture
Definition
Farmers (generally indigenous people) clean a new plot of about a hectare (2.5 acres) each year by cutting or girdling the tree. After a few weeks of drying this material is burned to prepare a rich seedbed of ashes. Fast-growing crops are planted immediately. Many different crops are planted (mixed perennial polyculture.) Yeilds are high & after a few years the forest takes over the garden again.
Term
Debt-for-nature swaps
Definition
Conservation organizations buy debt obligations on the secondary market to cancel the debt of poor developing countries if the debtor country will agree to protect or restore an area of biological importance.
Term
Clear cutting
Definition
Every tree in a given area is cut regardless of size.
Pros: Large machines can be used.
Cons: Even imature trees are cut, erosion occurs, elimates habitat.
Term
Strip cutting
Definition
Harvesting all the trees in a narrow corridor. This leaves strips of forest to help preven erosion.
Term
Selective cutting
Definition
Only small % of mature trees are taken in each 10 to 20 year rotation.

Shelterwood harvesting - removes mature trees in a series of 1 or 2 cuts.

Seed tree harvesting - Some mature trees are left to act as seed sources.
Term
Pasture & Open range
Definition
Pasture:Enclosed domestic meadows or managed grasslands.
Open range: Unfenced, natural prairie & open woodlands. (26% of the worlds land surface)
Term
Desertification
Definition
Process of denuding & degrading a once-fertile land & initiates a desert-producing cycle that feeds on itself.
Term
Rotational grazing
Definition
Confines animals to a small area for a short time (often only a day or two) before shifting to a new location. Prevents animals from eating all of the most desirable plants.
Term
Land reform
Definition
Redistribution of landownership to prevent many landless people in poverty.
Term
Indigenous people & lands
Definition
People = 10% of the global population but occupy about 25% of the land. There are about 5000 indigenous cultures.
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