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Forestry

Forestry. Outline. World Forests Tropical Forests Swidden Agriculture Temperate Forests Harvest Methods Fire Management. WORLD LAND USES. Earth’s total land area is about 29% of globe. 11% of landmass is now used for crop production.

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Forestry

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  1. Forestry Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  2. Outline • World Forests • Tropical Forests • Swidden Agriculture • Temperate Forests • Harvest Methods • Fire Management Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  3. WORLD LAND USES • Earth’s total land area is about 29% of globe. • 11% of landmass is now used for crop production. • Half of present forests and grazing lands could be converted. • Immediate and destructive impacts on landscape and wildlife. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  4. Uses of Landmass (29% of world) Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  5. 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. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  6. Forest Distribution • 1/3rd of original forests and woodlands have been converted to other uses. • Forests and woodlands cover 32% of earth’s land surface. • Greatest concern is over protection of Old-Growth Forests. • Only 22% retain old-growth characteristics. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  7. World Forests Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  8. Forest Products • Wood plays a part in more activities of the modern economy than any other commodity. • Industrial Timber and unprocessed logs account for about half of worldwide wood consumption. • Developed countries produce less than 1/2 all industrial wood, but account for 80% of consumption. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  9. Forest Products • US, Russia, and Canada are largest producers of industrial wood and paper pulp. • Japan is world’s largest wood importer. • US is both major exporter and importer. • Buy wood and paper from Canada and processed wood products from Japan. • Sell raw logs to Japan and other countries. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  10. 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 Cropping. • Disrupts ecological processes. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  11. TROPICAL FORESTS • Occupy 10% of landmass, and contain: • More than 2/3rds of all higher plant biomass. • At least 1/2 of all plant, animal, and microbial species. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  12. Tropical Forests Shrinking • 0.8% of remaining forest cleared each year. • Countries have economic and political reasons to hide extent of losses. • Brazil has largest rainforests, and highest rate of deforestation. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  13. Tropical Forests Shrinking Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  14. Cattle grazing Deforestation inthe Amazon Basin Logging Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  15. Tropical Forest Losses Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  16. Amazon Deforestation Remains High Even selective logging destroys canopy,causes river siltation, opens roads Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  17. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  18. Desertification threatens forest edges Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  19. Chipko Movement in India Women blocking mass logging, deforestation Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  20. Swidden Agriculture • Can be ecologically sound and sustainable if performed carefully and in moderation. • Slash and Burn • Small lot cleared, dried, and burned. • Ashes used to prepare seedbed. • Fast-growing crops planted to control erosion, shade crops, and anchor soil. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  21. Cropped intensively for 1-2 years, and then rested 10-15 years. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  22. Logging and Land Invasions • Other major source of forest destruction • Bulldozed roads make it possible for people to move into the forest for farmland. • Forest clearing leads to river degradation through increased silt and sediment flow. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  23. Debt-for-Nature Swaps • Banks, governments, and lending institutions hold nearly $1 trillion in loans to developing countries. • Conservation organizations buy debt obligations discount, and then offer to cancel the debt if the debtor country will agree to protect or restore an area of biological importance. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  24. TEMPERATE FORESTS • Northern countries have a long history of liquidating forest resources. • Siberia contains 1/4 of the world’s timber reserves. • Asian companies cutting 10 mil. acres/year Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  25. Temperate Forests in the U.S. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  26. 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 2nd only to tropical rainforests in biodiversity. • Accumulate more biomass in standing vegetation per unit area. • Less than 10% of virgin temperate rainforest remain • (80% scheduled to be cut). Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  27. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  28. Wilderness and Wildlife Protection • Forest products industry employs about 150,000 people in the Pacific NW • Adds nearly $7 billion annually to the economy. • Recreation has 16x jobs. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  29. Spotted Owl controversy • 1989 environmentalists sued USFS over plans to clear-cut remaining old-growth forests, • Argued spotted owls were endangered and must be protected. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  30. Spotted Owl controversy Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  31. Spotted Owl controversy • Timber industry claims 40,000 jobs lost. • Environmentalists dispute number. • Other reasons • Mechanization • Clear-cutting • Export of logs to Japan Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  32. 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. • Coppicing - Encourage stump-sprouts. • Seed-Tree - Leave few mature trees. • Shelterwood - Remove in series of cuts. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  33. 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. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  34. Menominee Sustainable Forestry Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  35. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  36. Below-Cost Salvage Sales • USFS has historically regarded its primary job as providing a steady supply of cheap 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. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  37. FIRE Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  38. Fires caused by poor logging practices Wisconsin, 1871: Deadliest forest fire in recorded world history kills 1,200-1,500 Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  39. Southeast AsianRainforest Fires, 1997 Palm oil plantations Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  40. Mexico/Central AmericaRainforest Fires, 1998 Cover for illegal logging Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  41. Brazilian AmazonRainforest Fires, 1999 Land-hungry farmers Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  42. 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. • As woody debris accumulates, chances of a major fire increase. • Often, attempts to stop fires cause more ecological damage than the actual fires. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  43. Fire Suppression:Wisconsin River Bluffs at Sauk City, 1870s-1990s Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  44. Fire Management • For 30 years, the NPS has followed a policy of allowing some natural fires to burn, and even setting some prescribed fires. • But after 70 years of fire suppression, fuel has now built up to a point where fires can easily escape “control.” • The dilemma is how to remove excess fuel while protecting property, human life, and forest ecosystems. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

  45. Yellowstone Fires, 1988 Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

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