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Chapter 18

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Chapter 18

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  1. Chapter 18 Land Resources and Conservation

  2. Mojave Desert

  3. Land Use • World Land Use

  4. Land Use in the United States • Administration of Federal Lands • 55% of US land is privately owned by citizens, corporations, and nonprofits organizations • 3% by native tribes • contains all types of ecosystems • Provide Important resources: minerals, fossil fuels, historical and cultural importance

  5. Land Use • Land Use in the US State 7% Federal Government 35% Private 55% Tribes 3%

  6. Land Use in the United States Managed by two US Agencies • US Department of the interior • #1 The Bureau of Land Mngmnt (BLM)national resource land 109 million hectares (270mil acres) • #3 Fish and Wildlife Services (FWS)National Wildlife refuges 37 million hectares (92 mil acres) • #4 The National Park Services (NPS)National Park System 34 million hectares (84 mil acres) • US Department of Agriculture • #2 US Forest Services (USFS) National Forests 77 million hectares (191 million acres)

  7. Land Use BLM • Administration of Federal Lands • BLM • 109 mil Hectares • (270) mil acres NPS USFWS USFS USFS 77 mil hectares 191 mil acres

  8. Land Resources and Conservation

  9. Importance of natural areas • Areas of low human density known as non-urban or rural lands. • Ecosystem services from these areas allow urban concentrations to exist. (environmental services such as clean air, clean water, fertile soil).

  10. DO NOW: • What are ecosystem services? How would you respond to the critic who says, "Forests are only good for providing timber"? Support your answer with examples of at least four different ecosystem services offered by forests.

  11. DO NOW: ANSWERs • Ecosystem services are important environmental benefits, such as clear air, water, and fertile soil that ecosystems provide. • Forests provide many goods and services to support human society besides lumber. • Forests supply nuts, mushrooms, fruits, and medicines. • Forests also influence local and regional climate conditions. • Biological cooling is a result of a process called transpiration. • Forests play an essential role in regulating global biogeochemical cycles, such as those for carbon and nitrogen. By acting as carbon “sinks,” forest help mitigate global warming. • At the same time, forests supply essential oxygen

  12. Land Use in these Natural Areas • Provide habitat, flood & erosion control, & groundwater recharge. • Natural areas also break down pollutants and recycle wastes. • Provide recreation (camping, hiking, fishing)

  13. Wilderness • Wilderness: Unspoiled regions where people visit but do not inhabit. • Wilderness Act of 1964 established federally owned lands to retain “primeval” quality (no permanent improvements or houses). • These lands remain unchanged for the benefit of future generations.

  14. Wilderness • Wilderness areas range from very small (The Big Gum Swamp in Florida @ 13,660 acres) to huge (Selway-Bitterroot Wilderness Area in Idaho @ 1.3 million acres).

  15. Wilderness • Wilderness areas are monitored by the NPS, USFS, FWS, and BLM. • 630 wilderness areas @ 102 million acres in the U.S., including mountains, tundra, deserts, & wetlands • 42% of wilderness areas are in national parks.

  16. National Parks • Yellowstone National park was the 1st (1872) • The National Park System (NPS) parks was established in 1916 and operates historic sites, battlefields, buildings, and towns in addition to natural areas.

  17. Problems with Wilderness Areas • Dilemma: preservation or human use and enjoyment? • Millions of visitors erode hiking trails, soil, water, waste, air pollution , litter, trash, traffic congestion. • # of visitors is now limited in some parks.

  18. Problems with Wilderness Areas • Exotic species can invade wilderness and upset the ecological balance. • Example: Pine blister Rust (fungus) is wiping out the White Pine (Pinus strobus) population. • Result...Pine seeds  Grizzly...Decline • Organization may have to plant disease resistant white pine trees. Is this still wilderness?

  19. Problems with Wilderness Areas Pine blister Rust (fungus)

  20. Problems with Wilderness Areas

  21. Wild and Scenic Rivers • Wild & Scenic Rivers Act was passed in 1968 to protect rivers of aesthetic, historic, & ecological value. • Not all wilderness but little or no development.

  22. Wild and Scenic Rivers NPS maintains the National River Inventory with 170 river segments @ 11,300 miles. • Recreation = yes  • Mining = yes  • Development = no 

  23. Land Use in the United States • 55% of US land is privately owned by citizens, corporations, and nonprofits organizations • 3% by native tribes • Encompasses varying ecosystems • Provide Important resources: minerals, fossil fuels, historical and cultural importance • Managed by two US Agencies

  24. DO NOW: Land Use in the United States • In the United States, national parks serve to provide biological habitat and facilitate human recreation. Discuss the impact of at least three threats to national parks. If a natural regulation policy were in place at a national park, what effect would it have on the management of the park? Why is natural regulation controversial?

  25. Answers • Overuse and overcrowding of the National Parks leads to urban problems of crime, vandalism, litter, traffic jams and pollution of the soil, water, and air. • Resource violations, including collection, plants, minerals, fossils and defacing historical structure have led to restrictions being placed on fragile environments in the park. • National Parks are not self-sufficient. The entrance fees alone are not adequate to maintain, repair and operate the parks. Human activities beyond park borders also affect national parks. Pollution does not respect park boundaries. • Some national parks also have imbalances in wildlife population. • Introduction of predators help to control prey populations. • Because fires are an integral part of national park ecosystems, with this policy in place, fires would not be suppressed unless they threaten people or buildings. The controversy over natural regulation involves what kinds of and how much human intervention are necessary to maintain ecological systems in pristine condition.

  26. Managed by two US Agencies 1. US Department of the Interior • The Bureau of Land Mngmnt (BLM) national resource land • 270 million acres b. Fish and Wildlife Services (FWS) National Wildlife refuges • 92 million acres c. The National Park Services (NPS) National Park System • 84 mil acres 2. US Department of Agriculture a. US Forest Services (USFS) National Forests • 191 million acres

  27. Wildlife Refuges National Wildlife Refuge system was established by Theodore “Teddy” Roosevelt in 1903. 535 refuges with at least one in each of the 50 states with 38.4 million hectares (95 million acres). These represent all the major ecosystems in the U.S. and are home to most of the endangered species (Whooping Cranes). Fish & Wildlife Service operates these lands for observation, fishing, hunting, photography, and education.

  28. Whooping Cranes ??

  29. Forests • Forests occupy less than 1/3 of the Earth’s total land area. • Forests have economic as well as ecological value. • Forests provide timber for fuel, paper, and construction. • Nuts, fungi, fruits, & medicines. Employment for millions, recreation and “escape” from urban areas.

  30. Forests • Forests provide ecosystem services; • They control the local climate via transpiration (natural cooling). • Control global biogeochemical cycles (nitrogen and carbon cycles) • Forests are carbon sinks & absorb copious amounts of CO2 from the atmosphere. • Roots anchor soil, protect watersheds, & provide habitat for varieties of organisms.

  31. Forest Management Practices • Tree “farms” or plantations are often monocultures with one variety of tree. Low diversity provides little habitat/Disease prone. • Herbicides & fungicides are used on tree farms because monocultures are more prone to disease & pests. • These farms limit the use of existing forests for timber and timber products.

  32. U.S. Forests • Vermont’s forests are increasing,. • The Rockies, New England, & the Great Lakes regions have been constant. • Conservation easements can protect forests by owners selling the right to develop the land to the U.S. government. The government then protects the land for a certain # of years.

  33. Forests • Natural Regulation: involves letting nature take its course most of the time, with corrective actions being taken as needed. • Introduced in 1968.

  34. Forests DO NOW: • Why was the 1968 Park management policy to allow natural regulation of many US national parks so controversial? Provide examples that are occurring in Yellowstone as we speak. • Hint think Elk over population.

  35. DO NOW: • Natural regulation of Yellowstone elk? Weather and predation (grizzlies and wolves) Follow-ups: • Why are wildfires not always suppressed at Yellowstone? • Why are they removing lake trout for Yellowstone?

  36. “New” Forest Management Practices • Ecologically Sustainable Forest Management involves mixing trees of different ages and species to increase diversity and available habitat for organisms as well as conserve forests for harvesting.

  37. Management Practices • Loggers, environmentalists, farmers, indigenous peoples, and government agencies need to cooperate for this type of management to be successful. • Wildlife Corridors are uncut to set aside zones that are connected to nearby un-logged areas.

  38. Wildlife Corridors

  39. Role of forests in the Hydrologic Cycle Chapter 17 Land Resources and Conservation

  40. Wilderness, Parks, and Wildlife Refuges • National Parks • Most popular

  41. Land Use in the Natural Areas • Provide habitat, flood & erosion control, & groundwater recharge. • Natural areas also break down pollutants and recycle wastes. • Provide recreation (camping, hiking, fishing)

  42. Wilderness, Parks, and Wildlife Refuges • National Parks • Threats to US Parks

  43. Land Use • World Land Use

  44. Forest Legacy Program in 1990 Farm Bill assists . . . Forests • Forest ownership in the US

  45. Forests • Trends in Tropical Forests

  46. Do Now- Harvesting Practices • Compare the 4 Types of tree harvesting in terms of methods, cost, and economic gain. • Selective Cutting • Shelterwood Cutting • Seed tree Cutting • Clearcutting(even-ages cutting)

  47. Harvesting Practices Selective Cutting: fells single trees or small groups of trees. Shelterwood Cutting: fells all the mature trees in an area over time. • Seed tree Cutting: fells almost all of the trees in an area except a few trees that are left to re-seed the area. • Clearcutting (even-age harvesting): fells all the trees from an area. (Cheapest type $$)

  48. Do Now- Harvesting Practices • Identify and discuss four ways in which forest trees are currently harvested. Which method is the most ecologically sound, and why? Which method is the most economical? If your answer is different for these two questions, how could a compromise be reached?

  49. Do Now- Harvesting Practices • Ans: Selective cutting harvests mature trees by cutting individual or small clusters of trees while the rest of the forest remains intact. This is ecologically sound because it allows the forest to regenerate naturally through seeding from remaining trees. While this method has fewer negative impacts on the forest community, it is not profitable in the short term because timber isn’t removed in great enough quantities. Shelterwood cutting removes all mature trees in an area over an extended period of time. The first harvest removes dead or diseased trees. The second harvest, perhaps ten years later, removes mature trees but leaves some of the largest to shelter the younger trees. After another decade, a third harvest removes the remaining mature trees. By now the younger trees are established. This method is ecologically sound because it prevents soil erosion and is self-sustaining. In seed tree cutting, almost all trees are harvest from an area leaving a scattering of desirable trees to provide seeds for regeneration. This method is not ecologically sound because it allows erosion and a severe alteration of the forest ecosystem, including loss of habitat for other organisms. Clearcutting is harvesting timber by removing all trees from a forest. Afterward, the area is either allowed to reseed and regenerate naturally or is planted with one or more variety of trees. This is the most cost effective method of harvesting forests yet it is ecologically unsound because it destroys biological habitats and increase soil erosion. The recreation and ecological services of forests are lost and sometimes the forests do not regenerate. Because selective cutting is the most ecologically sound and clearcutting is the most economical, a compromise could be reached by clearcutting selective patches of the forest. This might benefit the species who thrive in the regrowth of trees and shrubs that follow removal of the overhead canopy.

  50. Land Resources and Conservation