environmental conservation: forests, grasslands, parks, and nature preserves chapter 6

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Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

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Page 1: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Environmental Conservation: Forests,Grasslands, Parks, and Nature Preserves

Chapter 6

Page 2: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Outline:

• Tropical Forests• Temperate Forests

Harvest Methods and Fire Management• Rangelands

Overgrazing and Land Degradation• Parks and Nature Preserves

History - Problems - Size and Design• Wilderness Areas• Wildlife Refuges

Page 3: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Forests, woodlands = 33% land area

Ice, rock, desert etc. = 32%

Range, Pastures = 23%

Ag = 10%

Built land = 2%

FAO 1999,WRI 1998-1999 GLOBE

~ 66% area in RESOURCE EXTRACTION

Page 4: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

World Forests

Page 5: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

WORLD FORESTS

• Scenic, cultural, and historic value.• Provide valuable materials.

Wood, paper-pulp.• Forests play vital ecological roles:

Regulating climate, controlling water runoff, providing food and shelter for wildlife, and purifying air.

Page 6: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

World Wood Consumption, 1994 (% of total)

Fuelwood Fiber Non-fiber roundwood

Asia 93 1 6Africa 81 6 13South Am 50 31 19former USSR 44 17 39N/Cen Am 21 37 41Europe 15 33 52Oceania 7 14 79TOTAL 56 18 25

Page 7: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Forest Products

Page 8: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

DEFORESTATION: Charcoal production – Northern Brazil

Page 9: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Harvesting resinCollecting leaves for fodder

Himalayas - India

Page 10: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

India Himalayas – cutting trees for fire wood

Page 11: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

• About 25% of the world’s forests are managed for wood production.

• Monoculture forestry - single species• Ideal: scientific planning for sustainable

harvests

Page 12: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Estimated rate of tropical forest losses

Tropical Forest Issues

Page 13: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

DEFORESTATION: Valued timber species - Indonesia

Page 14: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Malaysia, palm oil

Page 15: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

SUSTAINABILITY

“ability to meet the needs of the present without compromising the ability of future generations to meet their own needs”(World Commission on Environment and Development, 1987)

Page 16: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

World Forests

70-80% of original

~ 30% of original

Page 17: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Forest Management• Approximately 25% of world’s forests are

actively managed for wood production. Sustainable harvest is key to regeneration.

- Many reforestation projects involve Monoculture Forestry.

Rapid growth and easier harvest. Disrupts ecological processes.

Page 18: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Tropical Forests

• Although they occupy less than 10% of earth’s land surface, tropical rainforests are thought to contain: More than two-thirds of all higher plant

biomass. At least one-half of all plant, animal, and

microbial species in the world.

Page 19: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Causes of Deforestation

• Thin, nutrient-poor tropical soils are usually worn out after a few years of cropping. Shifting cultivation often blamed for forest

destruction.- Can be sustainable where population

densities are low and individual plots are allowed to regenerate between cultivation periods.

Page 20: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Tropical Forest Losses

Page 21: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Slash and burn

Page 22: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Debt-for-Nature Swaps

• Banks, governments, and lending institutions hold nearly $1 trillion in loans to developing countries. Conservation organizations buy debt

obligations on the secondary market at a discount, and then offer to cancel the debt if the debtor country will agree to protect or restore an area of biological importance.

Page 23: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Temperate Forests

• Northern countries have a long history of liquidating forest resources. For many years, “multiple use” was the

official policy of the U.S. Forest Service.- Simultaneous uses.

Incompatibility ?

Page 24: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Temperate Forest Issues

• Logging of old-growth

• Endangered species vs. jobs

• Northern spotted owl

• Salmon• Natural resource

extractive economies – rural environments

Page 25: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Old-Growth Forests

• Today, less than 10% of the old-growth forest in the United States remains intact. ??? 80% of what is left is scheduled to be cut

down in the near future (in text) ??? NO!!!• Environmentalists sued U.S. Forest Service over

logging rates in WA and OR in 1989. Protection of

northern spotted owls.

Timber industry claimed 40,000 jobs would be lost.

Page 26: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Harvest Methods

• Clear-Cutting - Every tree in a given area is cut regardless of size. Fast and efficient, but wastes small trees,

increases erosion, and eliminates wildlife habitat.

• Shelterwood - Remove mature trees in series of cuts.

Page 27: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Harvest Methods

• Strip Cutting - Harvesting all trees in a narrow corridor.

• Selective Cutting - A small percentage of mature trees are taken in 10-20 year rotation. Can retain many characteristics of mature,

old-growth forests.

Page 28: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Loggings and Roads in National Forests

• Increasing number of people in the U.S. are calling for an end to all logging on federal lands. $4 Billion annual harvest vs. estimated

$224 Billion from recreation and ecological function.

• USFS builds roads in order for timber companies to extract trees. Hidden subsidy to timber industry.

Page 29: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Fire Management

• For more than 70 years, firefighting has been a high priority for forest managers. Many plant communities are fire-adapted. Accumulation of woody debris.

• Forest Service says 40% of all federal forest lands are at risk of severe fires. 68,230 fires burned 2.7 million ha in 2002.

- Firefighting costs of $1.6 Billion.• How to undo years of fuel build-up ?

Page 30: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Ecosystem Management

• 1990’s saw USFS shift from timber production to ecosystem management. Attempts to integrate sustainable

ecological, and social goals in a unified, systems approach.

• USFS is also using - ‘AdaptativeManagement’(trying new science, etc)

Page 31: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

RANGELANDS

• Pasture and Open range occupy about 25% of the world’s land surface. More than 3 billion domestic livestock

producing meat and milk.• Attractive and frequently converted to

human-dominated landscapes.

Desertification?

Page 32: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6
Page 33: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Rangelands

Number of threatened plant species - U.S.

(1990)

Page 34: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

New Approaches to Ranching

• Short-Duration Rotational Grazing Forces livestock to graze equally, trample

ground evenly, and fertilize with manure before moving on.

• Game Ranching Many wild species

forage more efficiently, resist harsh climates, and can fend off predators and pests better than domestic livestock.

Page 35: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

PARKS AND NATURE PRESERVES

• Origins and History Historically, sacred groves were set aside

for religious purposes, and grounds preserved for royalty.

- Only in the past 130 years have we begun to preserve wild places for the sake of wildlife and scenic beauty.

Page 36: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Park Problems• Many parks have become islands of nature

surrounded and threatened by destructive land- uses stemming from growing human populations crowding park boundaries.

Park rangers often spend more time on crime prevention and crowd control than natural history.

Mining and oil interests push to operate on private inholdings.

Page 37: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Bear snack?

Page 38: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Ecosystems not bounded by political considerations

Page 39: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Size and Design of Nature Preserves

• Single Large or Several Small (SLOSS) Ideally, a reserve should be large enough

to support viable populations of endangered species, keep ecosystems intact, and isolate critical core areas from external forces.

Page 40: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Good for some species but bad for others

Fragmentation

Page 41: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Corridors to join

existing protected

areas

Page 42: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Marine Preserves

• Shelter marine organisms from destructive harvest methods. Coral reefs among most threatened marine

ecosystems.- 90% face threats from sea temperature

change, destructive fishing methods, coral mining, sediment runoff and other human disturbances.

Page 43: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Conservation and Economic Development

• Tropics are suffering the greatest destruction and species loss in the world. Ecotourism can be more beneficial to

many countries over the long-term than extractive industries – BUT only if done ecologically and not as a money-making show only.

- Wildlife watching and outdoor recreation can be a welcome source of income for underdeveloped countries.

Page 44: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Indigenous Communities and Reserves

• Areas chosen for nature preservation are often traditional lands of indigenous people. 1986 UNESCO initiated its Man and

Biosphere Program (MAB).- Encourages division of protected areas

into zones with different purposes.

Page 45: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

WILDERNESS AREAS

• 1964 - Wilderness Act defined wilderness: “An area of undeveloped land affected

primarily by the forces of nature, where man is a visitor who does not remain…”

Most areas meeting these standards are in the Western US and Alaska.

Page 46: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

WILDLIFE REFUGES

• 1901 - President Teddy Roosevelt established 51 national wildlife refuges. Now 511 refuges encompassing 40 million

ha representing every major biome in NA.

Page 47: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Wildlife Refuges

• Over the years, a number of other uses have been allowed to operate within wildlife refuge boundaries. Oil and Gas Drilling Cattle Grazing Motor-boating, Camping

• Refuges also face threats from external sources - expanding human populations. Water Pollution

Page 48: Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6

Summary:

• Tropical Forests• Temperate Forests

Harvest Methods and Fire Management• Rangelands

Overgrazing and Land Degradation• Parks and Nature Preserves

History - Problems - Size and Design• Wilderness Areas• Wildlife Refuges