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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
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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
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.
Forest Distribution • Currently, forests (trees cover more than 10% of land) encompass 9.6 billion acres. • Greatest concern is over protection of Old-Growth Forests. • Areas that have been undisturbed by human activities long enough that trees can live out a natural life cycle. • Only 25% of forests still retain old-growth characteristics.
Forest Products • Wood plays a part in more activities of the modern economy than any other commodity. • Total annual wood consumption is about 3.7 billion metric tons. • $100 Billion each year. • Developed countries produce less than half of all industrial wood, but account for about 80% of consumption.
Forest Products • US, former Soviet Union, and Canada are largest producers of industrial wood and paper pulp. • Much of industrial logging in North America and Europe occurs in managed forests. • More than half of the world’s population depends on firewood or charcoal as their main source of heating and cooking fuel.
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.
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 forest are shrinking rapidly. • Estimated 0.6% of remaining forest is cleared annually. • Estimates are very rough. • Countries have economic and political reasons to hide extent of losses. • Real losses may range 5-20 million ha annually. • Brazil has largest rainforests, and highest rate of deforestation.
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.
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. • For many years, “multiple use” was the official policy of the U.S. Forest Service. • Simultaneous uses. • Incompatibility ?
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. • 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.
Joyce Kilmer Memorial Forest • 500 year old forest in Western, N.C.
Longleaf Pine Old Growth Forest - Eglin Air Force Base, Florida • “….preservation of the largest old growth longleaf pine forest in the United States — 2,000 acres, half the estimated 3,900 acres still in existence. “ http://gorp.away.com/gorp/activity/wildlife/topten_oldgrowth2.htm
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.
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.
Reforestation • Most reforestation is done by monoculture • After a clear cutting, the forest is replaced with one species such as slash or loblolly pine (SE) • Any competing species are removed before the planting of pines • This is a very efficient method because the trees grow fast and are easy to thin at 10 to 15 years old (allows for maximum yield) • Harvest is relatively easy 40-50 years after planting • Most of the harvests are used to make paper.
Problems of Monocultured Forests • Inherently unstable • Prone to diseases and or insect infestations which spread rapidly through these forests. • White pine blister rust is an invasive species and is lethal to these trees. • Pines in Georgia and across the southeast are subject to attack by at least six species of bark beetles. • http://www.barkbeetles.org/pbb/pbbpub.html • http://www.colostate.edu/Depts/bspm/Jacobi%20white%20pine.PDF#search='pine%20fungus'
Ants Monoculture Forests Too! • "Devil's gardens are large stands of trees in the Amazonian rainforest that consist almost entirely of a single species, Duroia hirsuta, and, according to local legend, are cultivated by an evil forest spirit," write Frederickson and her colleagues in Nature. "Here we show that the ant, Myrmelachista schumanni, which nests in D. hirsuta stems, creates devil's gardens by poisoning all plants except its hosts with formic acid. By killing other plants, M. schumanni provides its colonies with abundant nest sites—a long-lasting benefit, as colonies can live for 800 years." • http://news-service.stanford.edu/news/2005/september28/devil-092805.html
“A photo shot in Peru shows a devil's garden in the foreground in sharp contrast with the species-rich in vegetation the background.”
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.
Fire Management • For more than 70 years, firefighting has been a high priority for forest managers. • Many 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 ?
Should Salvage be Allowed? • After a fire or storm where there are many trees down, salvage operations are allowed on Federal lands. • Is this good for the ecosystem and also profitable for loggers? • Topic is controversial • Recent study suggests log salvage is harmful to the environment • Leaves too much debris and the operation kills young trees…counter intuitive!
“Biscuit timber salvage loses money A study cites a $14 million loss to the taxpayers and other reasons that logging after fires is harmful” • “Today’s report comes on the heels of a study released last week which concluded that logging burned trees at the Biscuit fire site killed large numbers of seedlings that sprouted on their own and increased the short-term danger of wildfire. That study was led by an Oregon State University graduate student in forest science. “ Jan 2006 http://www.mailtribune.com/archive/2006/0111/local/stories/07local.htm
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.
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.
Range Management • Pastoralists can adjust to environmental variations and resultant forage quality to keep livestock healthy and avoid overuse of any particular area. • Desertification has recently accelerated by expanding programs and political conditions that force people to overuse fragile lands.
Rangelands in the United States • Overgrazing has allowed populations of unpalatable or inedible species to build up on both public and private rangelands. • Grazing fees charged for use of public lands are often far below market value. • Hidden subsidy to western ranchers. • Permit holders generally pay less than 25% the amount of leasing comparable private lands.
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.
More on Short-Duration Rotational Grazing • Good results can be obtained, however: • Greater costs are incurred in fencing and water • Management costs are higher • Greater chance of parasitic infestations • Therefore, some farmers and ranchers are reluctant to use this method. http://www.ext.vt.edu/pubs/sheep/410-366/410-366.html
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 US area set aside to protect wild nature. • Authorized by President Abraham Lincoln. • Designated the first National Park by President Ulysses S. Grant in 1872. • Also first National Park in the world.
North American Parks • US national park system has grown to 280,000 km2 in 376 parks, monuments, historic sites and recreation areas. • 300 million visitors annually. • Canada has 1,471 protected areas occupying about 150,000 km2.
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.
Wildlife Issues • 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. • Excessively large ungulate populations in may parks have degraded the range such that massive die-offs occurred in severe winters.
Federal Parks in the Atlanta Region • Kennesaw National Battlefield • “The name Kennesaw is derived from the Cherokee Indian "Gah-nee-sah" meaning cemetery or burial ground. Kennesaw Mountain Battlefield is a 2,888 acre National Battlefield that preserves a Civil War battleground of the Atlanta Campaign. The battle was fought here from June 18, 1864 until July 2, 1864. Sherman's army consisted of 100,000 men, 254 guns and 35,000 horses. Johnston's army had 63,000 men and 187 guns. Over 67,000 soldiers were killed, wounded and captured during the Campaign.” The name Kennesaw is derived from the Cherokee Indian "
K.N.B.P. is a Great Birding Sitehttp://www.nps.gov/kemo/ • “…hike some of the 18 miles of interpretive trails; bring your binoculars and go bird watching…” • Its relatively undisturbed ecosystem provides shelter for many native birds and migrates. Wild Turkey Cerulean Warbler
The Chattahoochee River National Recreation Area • “…. It’s a rare occasion when within the city limits of one of our major cities, one can find pure water and trout and free canoeing and rapids and the seclusion of the Earth the way God made it. But the Chattahoochee River is this kind of place.” • President Jimmy CarterAugust 15, 1978
The Chattahoochee River National Recreation Areahttp://www.nps.gov/chat/pphtml/subanimals4.html • “The Chattahoochee River is the southernmost trout river in the United States. Buford Dam, at Lake Lanier, releases cold water from the bottom of the lake making the habitat conducive for trout. The Georgia Department of Natural Resources stocks the river with brown, rainbow and brook trout” (48 river miles) Brook Trout Fly fisherman at the Palisades. Julie Burroughs
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.
Chattahoochee National Forest • Multiple use concept • Forest products • Watershed management • Recreational uses Including “Wilderness Experience”
Cohutta Wilderness Area http://www.conasaugariver.net/resource/wilderns.html • 1976, 36,000 acres were deemed wilderness. Since that time more wilderness area has been added.
WORLD PARKS AND PRESERVES • In many cultures wilderness and wild lands are regarded as useless wastelands. • Many preserves are too small to maintain significant biological populations over the long term. • Currently about 300 biosphere reserves have been designated in 75 countries.
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.