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Mrs. Sealy - APES

Mrs. Sealy - APES. Importance of Forests. Economic - housing, fuelwood, paper, medicines, resins, gums, dyes, lumber, jobs, recreation - lands are used for mining, grazing, timber extraction and recreation - one tree = about $600-$900. Importance of Forests. Ecological

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Mrs. Sealy - APES

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  1. Mrs. Sealy - APES

  2. Importance of Forests • Economic - housing, fuelwood, paper, medicines, resins, gums, dyes, lumber, jobs, recreation - lands are used for mining, grazing, timber extraction and recreation - one tree = about $600-$900

  3. Importance of Forests • Ecological - support energy flow and chemical cycling - reduce soil erosion -absorb and release water -purify water and air -influence local climate -store carbon -release oxygen -wildlife habitats The forest provides $4.7 trillion per year in ecological services

  4. Old Growth vs. Secondary Growth • Old growth: virgin (uncut) forests or regenerated forests untouched for several hundred years (22% world) • Secondary Growth: forests that result from secondary ecological succession after cutting (63% worlds forests) • Tree farm and plantations: managed tracks of uniformly aged trees (5% - mostly in China, US, India, Japan)

  5. Ecology of Old Growth Forests • Takes 350 years for forest to reach its prime in terms of biodiversity • Functions: - large accumulation of snags, which slowly decompose and recycle nutrients -Unusually rich in biodiversity -Act as sponges to recharge streams and aquifers

  6. What is happening to the world’s forests • In the last 8,000 years 50% of the forests have disappeared • The world’s forests are shrinking by 54,000 square miles per year (90% in the rainforests) • 6% forest loss per decade • Those remaining are disappearing at rate of 129 football fields/day • If current rates continue, 40% of the world’s remaining intact forest will be gone.

  7. Effects of Deforestation • Decreased soil fertility • Run-off of eroded soil into aquatic ecosystems • Premature extinction of species • Habitat loss • Regional climate change • Release of CO2 in atmosphere • Acceleration of flooding

  8. Forest Management • Even-aged: trees in a given stand are maintained at the same age and size. All one type of tree seedling planted after an old growth forest is clear cut – grow and slash deforestation – depletes the soil so growers are forced to move onto and destroy new areas of forest

  9. Forest Management • Uneven-aged management: a variety of tree species in a given stand is maintained at many ages and sizes to foster natural regeneration. Biological diversity, long term production, high quality timber, reasonable economic return

  10. Tree harvesting • Logging Roads: cause erosion, sedimentation of waterways, habitat fragmentation, expose forests to exotic pests and non-native species, open forests to farmers, ranchers, off-road vehicles, hunters and miners * 400,000 miles of logging roads have been cut through national forests at taxpayers expense.

  11. Tree harvesting • Selective Cutting: middle-aged or mature trees are cut singly, selection reduces crowding, encourages growth of younger trees and allows for natural regeneration

  12. Tree harvesting • . Clear-cutting: cutting everything in a single cut, then reforesting with monocultures. Fragments wildlife habitats and destroys ecological integrity. Destroys soil, leads to severe soil erosion. This can be done responsibly with some trees

  13. Clear Cutting Advantages Disadvantages Reduces biodiversity Disrupts ecosystems Destroys, fragments habitats Leaves large openings Increases water pollution, flooding, and erosion on steep slopes Eliminates recre4ational value. • High timber yield • Maximum profits in short period of time • Can reforest with fast growing tree plantations • Needs less skill and planning • Good for species who need full sunlight

  14. Tree harvesting • Strip Cutting: only removing trees in corridors small enough to allow natural regeneration

  15. Sustainable Forestry • Using fiber from fast growing plants like kenaf to make paper • Growing timber on longer rotations 100-200 years • Selective cutting • Minimizing fragmentation • Use of logging and road building practices that minimize soil erosion • Banning clear cutting on slopes • Leaving most standing dead trees and fallen timber to recycle nutrients • When evaluating economic value take into consideration ecological and recreational services that forests provide

  16. How Pathogens Affect Forests • Dutch Elm, Bark Beetle, White Pine Blister Rust • Happens when the trees become unhealthy because of drought and pollution • To reduce the impact: preserve biodiversity, ban imported timber, remove infected trees, treat infected trees with antibiotics, develop disease resistant trees, apply pesticides, Integrated Pest Management

  17. How Fires Affect Forests • Intermittent fires set by lightening are a natural part of the ecological cycle • Fires are a natural part savanna, grasslands, chaparral • Burn away flammable ground material • Release valuable nutrients tied up in leaf litter • Stimulate the germination of certain seeds • Help control pathogens and diseases

  18. Old Growth Deforestation in US - There are more forests now than in 1900, which is mainly secondary growth and tree farms. - More wood is grown than is cut -In the east old growth forests have grown back naturally. - On the other hand an increasing area of old growth forest on public land is being clear cut and replaced with tree plantations. (what environmentalists care about) - Most old-growth forests are fragmented and are in WA, CA and Oregon Good news Bad news

  19. The Logging Controversy – Logging in national Forests Advantages Disadvantages Provides only 4% of our timber needs Has little effect on timber and paper prices Degrades biodivsersity Damages nearby rivers and fisheries Creates fewer jobs than recreation Has cost taxpayers 6.7 billion dollars over the last 10 years Lost money for taxpayers in the last 97 out of 100 years • Helps meet our timber needs • Provides jobs • Increases timber company profits because they pay very little to take logs off of public land • Promotes economic growth

  20. Why should we cut old growth forests? • Provides 100,000 jobs, If it were stopped it would effect regional economics and cost 52,000 jobs • Forest service supplements its budget with timber money • Elected officials in local communities push for increased timber harvesting because the communities get 25% of money from logging National Forests

  21. Why should we save the 5-8% of Virgin forests on public lands? • The Spotted Owl only lives in two hundred year old Douglas fir and it is on the endangered species list. So it is used to protect old growth forests and that is why the timber industry is pushing to end the endangered species act • The remaining ancient forests are a national treasure whose ecological, scientific, aesthetic and recreational values far exceed the economic value of cutting them down for short term gain • This land is owned by all citizens, not just residents of the region, it is a global issue. • If logging is allowed on Public lands it will only save a decade or so of logging jobs • The Salmon industry is linked to old growth forest and provides jobs for 62,000 people and $1.2 billion.

  22. How can you protect jobs and conserve old growth forests? • Stop export of raw logs from public land • Tax exports of raw logs from private land, but not finished logs • Subsidize revamping sawmills to cut smaller secondary growth logs • Federally funded reforestation • Make tourism a revenue source for the forest service • Provide job retraining • Protecting half of all old growth forests • Sharply reduce new roads on public land • Selling tax deductible easements to conservation groups • Adopting a user pay approach for timber companies

  23. Canada • Canada has 10% of the world’s forests, but it has lost 60% of its old growth forests, less than 20% of protected • British Columbia supplies half the country’s timber and pulp, more than half of British Columbia has been clear cut • More than half the world's temperate rainforests are in B.C. and are slated to be logged • Canada provides massive subsidies, but most of the profit goes to Japan

  24. How fast are Tropical Forests Disappearing • Estimates from satellite mapping range from 19,300 square miles to 65,600 square miles (estimates vary due to difficulties in making measurements and countries lie) • Haiti has lost 98% of its forest • Philippines has lost 97% • Madagascar has lost 84% • Brazil has lost 47% (93% of Brazil’s coastal rainforest is lost.) Brazil loses 11 football fields a minute of rainforest due to logging, ranching and farming!!!!

  25. Why should we care about Tropical deforestation? • Biologists consider the plight of tropical forests to be the world’s most serious environmental problem • These forests are home for 50-90% of the world’s terrestrial species • They supply half the world’s hardwoods • Supply hundreds of food products such as mango, coffee, chocolate, bananas • Supply latex, resins, dyes and essential oils • 25% of world’s medicines supplied by rainforest plants - $100 billion a year industry • 70% of 3,000 plants identifed to treat cancer are from the rainforest • Possible new food sources – only 1% of 125,000 plants has been examined as possible use for human resources Aerial View of Sediment Run-off Caused by Massive Amazon Deforestation. This entire area has been stripped bare of forest, so there are no longer any plants, bushes or tree roots to hold soil...which runs off into rivers and streams, killing marine life, even after the animals on land have been killed due to deforestation.

  26. Cultural Extinction in Tropical forests • One person in 20 are indigenous to the rainforest, they have been living in and using tropical rainforests for centuries • Many of the world’s tribal peoples are seeing their homes cut, mined, contaminated, burned etc. • Those who resist are killed by miners, ranchers and farmers • It is a loss of cultural diversity and a loss of earth wisdom At least 52 people have been killed in 24 hours of violence between indigenous protestors and the Peruvian army in a dispute over land rights in the Amazon rainforest.

  27. What causes tropical deforestation? • Governments grant title to the land that peasants clear in Mexico, Brazil and Indonesia, so peasants logging roads where they clear land to try to grow food to survive • Governments subsidize farming, logging and grazing making lumber relatively cheap • International banks lend huge sums of money for unsustainable projects such as mines, logging operations, oil drilling and dams. • Loggers use selective cutting to remove logs, but fail to cut the Liana vines first causing extensive damage. Most logging is done by foreign companies under government concessions.

  28. In Brazil, governments subsidize $5.6 million per ranch, allowing them to claim large tracts of land and the mineral rights below • Often these ranchers sell the land for a quick profit, half the ranches in Brazil have never sent a single head of cattle to market • Central America has lost two-thirds of forest for cattle grazing to meat to the US and Canada. • Mining, oil extraction = loss of trees and toxic pollution • Large sections of land are cleared for soy beans, biodiesel, palm oil, sugarcane etc. • Burning of the forest has lead to patchy remnants of forest that dry out, thus converting the areas to grassland – this is called savannization.

  29. What causes tropical deforestation? • Dams in the Amazon flood large areas of tropical forest, There are 76 dams planned in the next 20 years that will flood an area the size of Georgia to supply power for smelting and mining • Fuelwood extraction not a problem in tropical forests, but a problem everywhere else

  30. How can we reduce tropical deforestation • Protect Hot spots – areas of critical habitat that are in imminent danger • Reduce poverty • Reduce the flow of landless poor to the rainforest • Establish programs to help settlers in the rainforest practice sustainable agriculture • Phase out government subsidies and charge user fees • Encourage governments to protect it by setting up preserves and parks • Debt for nature swaps • Label sustainable lumber • Reduce illegal lumber cutting • Cut canopy vines before harvesting trees • Concentrate peasant farming on land already cleared • Discourage overconsumption • Transfer control of forests from federal government to local communities

  31. Managing Rangelands and Grasslands • Rangelands are unfenced grasslands in temperate and tropical regions that supply vegetation for grazing animals • Moderate grazing is healthy for grasslands • Overgrazing is when to many animals graze for too long and exceed the carrying capacity of the area which causes damage. • Cows also should not be allowed to graze near riparian areas • Overgrazing causes compaction of the soil and kills young grass

  32. Establishing Reserves • Large reserves are needed to help sustain all the world’s major types of terrestrial ecosystems • Reserves should be set aside to protect endangered species • Reserves should be in areas with a high biodiversity • Create reserves in hot spots

  33. U.S. Public Lands • Multiple Use Lands - National Forest System: 156 forests, 20 grasslands, run by the department of forestry according to sustainable yield and multiple use such as mining, logging, grazing, wildlife, soil and water resources - National Resource Land: deserts, scrublands, prairies. Managed by BLM (Bureau of Land Management), resource reserves for domestic supplies of energy and minerals

  34. U.S. Public Lands • Moderately Restricted - National Wildlife Refuges – 508, run by Fish and Wildlife to protect habitats and breeding areas for waterfowl and big game for hunters and to protect species from extinction. Allow logging, mining, grazing, and military if the Department of the Interior allows it.

  35. U.S. Public Lands • Restricted Use Lands - National Park System – managed by National Park Service, goals are to preserve natural landscapes, historical and cultural heritage, includes parks, recreation areas, monuments, memorials, battlefields, historic sites, rivers, trails and seashores

  36. Managing and Sustaining National Parks • How are parks threatened? - too many visitors - pollution created outside the park - too small to sustain viable populations of endangered animals

  37. How Parks are being threatened in developing countries? • 99% of protected areas in other countries are protected in name only • Problems with poachers, loggers, miners • Not enough money or manpower to protect them

  38. Designing Reserves • The best shape is circular • It is better to have a large single reserve than several smaller ones • It is better to have one reserves with many different habitats • If smaller reserves are created there should be wildlife corridors linking them together

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