Forests and Range lands

 

Land Use Distribution of World:

  • 32% Forest and woodlands- mostly in the US, Russia and S. America
  • 26% Range and pasture
  • 11% Cropland
  • 33% Other

Forests

Old Growth Forests- remnants of ancient forest contain much of the world's biodiversity and endangered species! Less than 10% virgin forest remains in US.

Characteristics include: Mixture of young and old trees. Multilayered canopy and little forest floor growth.

Spotted Owls vs. Lumberjacks. Environmentalists sued U.S. Forest Service over plans to cut all of remaining old growth forest in Oregan and Washington State. Spotted Owls are an endanged species. Result: Victory for the _______!!!!

Tropical Forests- (Rainforests/Jungles) are critically threatened. Less than 10% Earth. Located in S. America, Central Africa and SE _______. Jungles contain 2/3 of all plants and ____ of all animal life. There need to be laws preventing deforestation in developing countries.

Benefits: Forests regulate local and global climate (fights global __________!!), controls water runoff and soil _________, cleans water, provides shelter and food and purifies the air. Helps recharge aquifers and increases local rainfall. Great carbon sink. Provides wood, paper pulp. Plus they are pretty to look at!

Deforestation: _______ of the world original forests have been distroyed. :(

Forest Products:

  • Timber- 1/2 used for lumber: plywood, particleboard, paper, veneer and 1/2 for ______
    • 80% consumption by developed countries
  • Heating and Cooking- 1/3 world population depends on wood for this

 

Forest "Mis-management":

More forests is being cut down than replanted. 25% of forests are managed for wood.

Monoculture forestry -Tree plantations of single species are the most profitable but the most __________ to the health of the forest. Pests and disease abound. Most countries harvest more than they replant. :( Trees are often not native.

Logging old-growth forest

Harmful timber harvest methods

  • Clear cutting is when every tree in a given area is ______ regardless of size. Top soil erosion is intense especially on hills. Landslides more common. The concentration of nitrates in the runoff increases. Water temperature and flooding in streams increase.
  • Strip cutting entails harvesting all trees in a ________ corridor.
  • Even-age management- all trees removed at once

U.S. Forest Service is all about providing cheap timber not protecting nature!!! National Forests are holding area for trees for future ___________.

 

Sustainable Land Use Strategies

Better methods of timber harvesting

  • Uneven age management- trees removed in stages
  • Seed tree cutting- small seed producing trees are left standing
  • Swidden Agriculture- (Slash and Burn) An ecologically sound way of farming in the jungle. One hectare (2.5 acres) are felled and burned. Ash provides food for rich array of crops- mixed perennial polyculture. Abandoned in 2 years. Highly __________ and sustainable.
  • Selective cutting is when only a small percentage of the mature tress are taken in each 10- or 20- year rotation.
  • Increasingly, non-timber forest products are seen as an alternative to timber production. ex. nuts, berries, thatch

Debt-for-Nature Swap- banks and govenments forgive loan pay back by 3rd world countries in turn for jungle ____________!!! Yay!

Fire Management:

  • A normal part of healthy forest- most federal land fires are allowed to burn.
  • Fire suppression has eliminated small fires- causing ______ fires. Crown fires are such high temperatures that trees burn from treetop to treetop. The only way to stop them is prescribed burning which thins out the forest underbrush (surface fires) or prevention which is not a long term solution.
  • Salvage cutting- removal of ________ trees supresses disease and fire timber.

Sustainable Forestry: In both temperate and tropical regions, certification programs set by FSC- Forest Stewardship Council are being developed to identify __________ produced wood products. Cooperatives, second or third generation forests and recycled paper products.

 

Rangelands

Pasture (generally enclosed domestic meadows or managed grasslands) and open range (unfenced, natural prairie and open woodlands) occupy about 27% of the world's land surface. Losing grasslands faster than forests.

Overgrazing: About _________ of the world's range is severely degraded by overgrazing, making this the largest cause of soil degradation. When plant roots die, the soil quality plummets and erosion is rampant.

The process of denuding and degrading a once-fertile land initiates a desert-producing cycle that feeds on itself and is called ________________. Animals eat all the plant life, rain washes away soil, springs and wells dry up, vegetation is removed for firewood and the soil erosion spreads.

Rangeland (MIS)Management:

Federal Rangelands

  • Managed by Bureau of Land Management (BLM not BLT) and U.S. Forest Service: controversial methods. Subsidized grazing permits bad!
  • Overgrazing big issue.

Solutions

  • _________ number of animals grazing (below carrying capacity)!!
  • Rotational grazing: confining animals to a small area for a short time (often only for a day or two) before _________ them to a new location; stimulates the effects of wild herds. This allows the animals to trample and fertilize the ground without damaging it.
  • Mixed species herd: all vegetation used equally- no overgrazing of ______ type
  • Other rangeland management techniques include letting land rest so vegetation can rebuild or fertilizing, water and seeding the grazing area.
  • Prescribed burning kills invasive species or otherwise suppressing invasive species growth.

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