Conservation: Forests, Grasslands and Nature Preserves
Objectives
Summarize some forest types and the products we derive from them
Report on how and why tropical forests are being disrupted
Understand the major issues concerning forests in developed countries
Outline
Outline extent, location and state of grazing lands around the world
Describe how overgrazing causes desertification
Understand the origins and current problems of protected areas in the United States and elsewhere in the world
World forests
Forests play vital ecological roles
–Regulating climate, controlling water runoff, providing food and shelter for wildlife, and purifying air
Provide valuable materials
–Wood, paper-pulp
Scenic, cultural, and historic value
What is a forest?
A forest is an area where trees cover 10 percent or more of the land
Includes open woodlands, thorn shrub, savannas, and closed-canopy forests
How much forest is there ?
One-third of original forests and woodlands have been converted to other uses
Currently, forests and woodlands cover 29% of earth’s land surface
Old-growth Forests
Have been undisturbed by human activities so that trees can live out a natural life cycle
Lots of concern over protection of these forests
Only one-quarter of forests still retain old-growth characteristics
–Russia, Canada, Brazil, Indonesia and Papua New Guinea have three-quarters of world’s old-growth forests
Forest products
Wood plays a part in more activities of the modern economy than any other commodity
Industrial timber and unprocessed logs account for a little less than half of worldwide wood consumption
Developed countries produce less than half of all industrial wood, but account for about 80% of consumption
Forest products
At least one-third of world’s population depend on firewood or charcoal as their principle source of heating and cooking fuel
Fuelwood accounts for over half of all wood harvested worldwide
–About 1.5 billion people have less than they need
Open fires
Open fires deliver only one tenth of available heat to cooking surfaces
Simple technology can be four times as efficient and reduce air pollution
Forest management
Approximately 25% of world’s forests are actively managed for wood production
–Sustainable harvest is key to regeneration
Most countries replant far fewer trees than were harvested
Many reforestation projects involve monoculture forestry
–Disrupts ecological processes
–Encourages pest and disease infestations
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
Diminishing forests
Tropical forests are shrinking rapidly
–Estimated 0.8% of remaining forest is cleared annually – 1 acre is cleared every second around the clock
Congo and Amazon river basins have highest rate of deforestation in the world
Milpa or swidden agriculture
Can be ecologically sound and sustainable if performed carefully and in moderation
Slash and Burn
–Hectare plot cleared, dried, and burned
Ashes used to prepare seedbed
–Fast-growing crops planted to control erosion, shade crops, and anchor soil
Cropped intensively for 1-2 years, and then rested 10-15 years
–Mixed perennial polyculture technique mimics diversity of jungle itself
–Rotations are getting shorter and shorter
Logging and land invasions
Other major source of forest destruction is logging and subsequent human colonization
–Bulldozed roads make it possible for large numbers of immigrants to move into the forest in search of farmland
–Forest clearing leads to river degradation through increased silt and sediment flow
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
Temperate forests
Northern countries have a long history of liquidating forest resources
–Siberia contains one-fourth of the world’s timber reserves
Four-million ha felled annually
In the U.S. and Canada, two main timber management issues are:
–Cutting old-growth forest remnants
–Timber harvest methods
Ancient forests of the Pacific Northwest
Redwoods can reach 3-4 m in diameter, 90 m in height and 1,000 years in age
Temperate rainforests are second only to tropical rainforests in terrestrial biodiversity
Accumulate more biomass in standing vegetation per unit area than any other ecosystem on earth
Less than 10% of virgin temperate rainforest remain (80% scheduled to be cut in the near future)
Spotted owl controversy
Forest products industry employs about 150,000 people in the Pacific NW, and adds nearly $7 billion annually to the economy
–1989 environmentalists sued USFS over plans to clear-cut remaining old-growth forests, arguing spotted owls were endangered and must be protected
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
Early-successional species flourish
Harvest methods
Selective cutting - A small percentage of mature trees are taken in 10-20 year rotation
–Can retain many characteristics of mature, old-growth forests
One year later…
U.S. forest management
USFS has historically regarded its primary job as providing a steady supply of logs to the nation’s timber industry
–Often, timber prices have not been enough to repay management costs
Hidden subsidy to timber industry
–USFS builds roads in order for timber companies to extract trees
National Forest
Harvesting of trees adds $4 billion to the U.S. economy each year
Recreation, fish and wildlife, clean water and other ecological services add $224 billion per year
Roadless areas a current controversy
–Bush administration overturned Clinton’s “Roadless Rule” and ordered resource managers to expedite logging, mining and motorized recreation
Fire management
For more than 70 years, firefighting has been a high priority for forest managers
Forest fires
2002 was one of the biggest fire years on record, with nearly 2.8 million ha of forests and grasslands burned
Fire management
Recent studies show fire plays an important role in many forested ecosystems
–Eliminating fire has allowed shrubs and small trees to fill some forest floors, crowding out grasses and forbs
As woody debris accumulates, chances of a major fire increase
–Often, attempts to stop fires cause more ecological damage than the actual fires
Fire management
After a fire, many industry advocates encourage salvage logging
–Removal of dead or dying trees from forests damaged by fire or disease
In 1995, Congress passed a budget bill containing a rider allowing salvage logging to bypass ordinary environmental reviews or logging limits
Recently the Forest Service proposed a massive new program of forest thinning and salvage logging
Sustainable forestry and non-timber forest products
In both temperate and tropical regions, many certification programs are being developed to identify sustainably produced wood products
–Forest Stewardship Council
Increasingly, non-timber forest products are seen as an alternative to timber production
Grasslands
Grasslands currently cover about 27% of the world’s land surface
More than 3 billion domestic livestock producing meat and milk
Grasslands and open woodlands are attractive for human occupation, thus are frequently converted to human-dominated landscapes
Overgrazing and land degradation
About one-third of the world’s rangeland is severely degraded by over-grazing
Grazing animals usually exhibit selective grazing, removing preferred species and leaving non-preferred species to survive and reproduce
Gradually, nutritional value of forage declines
Denudation of ground leads to desiccation and desertification
Rangelands in the United States
U.S. has approximately 319 million ha of rangeland
–Most in the West
About 60% is privately owned
Only 2% of cattle and 10% of sheep graze on public land
–BLM manages more land than any other agency in the U.S.
Strong agency inclination towards resource utilization
State of the range
Natural Resource Defense Council claims 30% of public rangelands are in fair condition, while 55% are in poor or very poor condition
Overgrazing has led to an abundance of unpalatable or inedible species, such as mesquite, sage and cactus
Grazing fees
Fees charged for grazing on public lands are far below market value and represent an enormous hidden subsidy to western ranchers
–1999 minimum charge was $1.35 per cow per month
Comparable private land fees were $11.10 per cow per month
–Estimates are that administrative costs alone are $3.21 per animal unit
Rotational grazing
Short duration confinement of animals to a small area (day or two) before shifting them to a new location simulates the effects of wild herds
Maintains forage quality
Keeps weeds in check and encourages growth of more desirable forage species
Harvesting wild animals
U.S. National Academy of Sciences concluded the semiarid lands of the African Sahel can support 20-28 kg of cattle per hectare, but can produce nearly three times as much meat from wild ungulates in the same area
Game ranching
Many wild species forage more efficiently, resist harsh climates, and can fend off predators and pests better than domestic livestock
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
Yellowstone
First U.S. area set aside to protect wild nature
–Authorized by President Abraham Lincoln
Designated the first National Park by President Ulysses S. Grant in 1872
Parks
U.S. national park system has grown to 280,000 km2 in 376 parks, monuments, historic sites and recreation areas
–300 million visitors annually
US and Canada have the greatest area of protected area, followed by Australia, Greenland and Saudi Arabia
–All have large thinly populated or resource poor lands available
Trouble in our parks and monuments
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
While number of visitors has increased by one-third over the past decade, park budgets have decreased by twenty-five percent
Trouble in our parks and monuments
Air Pollution
–Power plants
–Most snowmobile and PWC engines produce as much air pollution in 7 hours as a car in 100,000 miles
Traffic congestion
Conversion of inholdings to incompatible uses
Mining and oil interests
13 monuments opened to oil and gas drilling under Bush administration, including only breeding ground in US for sea turtle species
New parks and monuments
One solution to congestion and overuse is to create new parks
–Grand Staircase-Escalante in 1997
Desert canyonlands in southern Utah
–Sits atop potentially trillions of dollars worth on natural resources
–Clinton established 2 million ha of national monuments and expanded national parks and underwater preserves
Many have been dismantled or undermined by Bush administration
Wildlife in parks
Historically, parks killed “bad” animals (wolves) in favor of “good” animals (elk)
–Critics contend this policy unbalanced ecosystems, and created a false illusion of a natural system
Park Service now maintains a policy of “natural regulation”
Wolf reintroduction in parks
Wolves extirpated by humans
Herbivores reach 4-5 times carry capacity of environments
Reintroduction seeks to “re-balance” nature
Controversy between ranchers and conservationists
Wilderness areas
Wilderness areas
–A belief that wilderness is a source of wealth and the origin of strength, self-reliance, wisdom, and character, is deeply embedded in our culture
–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…”
40 million ha in US in 264 wilderness preserves
Wildlife refuges
1901 - President Teddy Roosevelt established 51 national wildlife refuges
–Now 540 refuges encompassing 40 million ha representing every major biome in North America
Refuge management
–Originally intended to be sanctuaries in which wildlife would be protected from hunting or other disturbances
1948 - Hunting allowed in refuges
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
Alaska National Wildlife Refuge (ANWR)
World parks and preserves
The idea of setting aside nature preserves has spread rapidly over the past 50 years
–Regions with the most dramatic increases have been Asia, North America, and Latin America
–Brazil has recently pledged to protect 12% of its rainforest
Paper parks
–In many cases, it is easier to declare a new park than protect and manage it
Even existing parks are not safe from exploitation
International wildlife preserves
Tanzania’s SerengetiNational Park was established in 1940 to protect 15,000 km2
–Problems
Human populations on boarders
Herds of domestic cattle
Poachers
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 disturbance
Indigenous communities and biosphere 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
Allows both use and protection of resources
Conservation and economic development
Ecotourism can be more beneficial to many countries over the long-term than extractive industries
Wildlife watching and outdoor recreation can be a welcome source of income
Ecotourism
Parks as Ecosystems
One of the biggest problems with managing parks and nature preserves is that boundaries are often based on politics rather than ecological considerations
–Airsheds, watersheds, and animal territories, and migration routes often extend far beyond official boundaries
Biogeographical area must be managed as a unit
Size and design of nature preserves
For some species with small territories, several small isolated refuges can support viable populations
–But cannot support species requiring large amounts of space
Corridors of natural habitat to allow movement of species from one area to another can help maintain genetic exchange in fragmented areas