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

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Presentation on theme: "Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves Chapter 6."— Presentation transcript:

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

2 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

3 Forests, woodlands = 33% land area
FAO 1999, WRI GLOBE Forests, woodlands = 33% land area Ice, rock, desert etc. = 32% Range, Pastures = 23% ~ 66% area in RESOURCE EXTRACTION Ag = 10% Built land = 2%

4 World Forests

5 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.

6 World Wood Consumption, 1994 (% of total)
Fuelwood Fiber Non-fiber roundwood Asia 93 1 6 Africa 81 13 South Am 50 31 19 former USSR 44 17 39 N/Cen Am 21 37 41 Europe 15 33 52 Oceania 7 14 79 TOTAL 56 18 25

7 Forest Products

8 DEFORESTATION: Charcoal production – Northern Brazil

9 Himalayas - India Collecting leaves for fodder Harvesting resin

10 India Himalayas – cutting trees for fire wood

11 About 25% of the world’s forests are managed for wood production.
Monoculture forestry - single species Ideal: scientific planning for sustainable harvests

12 Tropical Forest Issues
Estimated rate of tropical forest losses

13 DEFORESTATION: Valued timber species - Indonesia

14 Malaysia, palm oil

15 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)

16 World Forests 70-80% of original ~ 30% of original

17 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.

18 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.

19 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.

20 Tropical Forest Losses

21 Slash and burn

22 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.

23 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 ?

24 Temperate Forest Issues
Logging of old-growth Endangered species vs. jobs Northern spotted owl Salmon Natural resource extractive economies – rural environments

25 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.

26 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.

27 Harvest Methods Strip Cutting - Harvesting all trees in a narrow corridor. Selective Cutting - A small percentage of mature trees are taken in year rotation. Can retain many characteristics of mature, old-growth forests.

28 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.

29 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 ?

30 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 - ‘Adaptative Management’ (trying new science, etc)

31 Pasture and Open range occupy about 25% of the world’s land surface.
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?


33 Rangelands Number of threatened plant species - U.S. (1990)

34 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.

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.

36 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.

37 Bear snack?

38 Ecosystems not bounded by political considerations

39 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.

40 Fragmentation Good for some species but bad for others

41 Corridors to join existing protected areas

42 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.

43 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.

44 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.

45 WILDERNESS AREAS 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.

46 WILDLIFE REFUGES President Teddy Roosevelt established 51 national wildlife refuges. Now 511 refuges encompassing 40 million ha representing every major biome in NA.

47 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

48 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

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