Maintaining Terrestrial Biomes

1. Maintaining Terrestrial Biomes

2. In the United States, the government manages public lands including forests, parks, and refuges. • Their use varies from resource extraction to farming to recreation.

3. Multiple use lands include those in the • National Forest System • Managed by the U.S. Forest Service • National Resource Lands • Managed by the Bureau of Land Management • National Wildlife Refuges • Managed by the U.S. Fish and Wildlife Service

4. Permitted activities include: • logging

5. mining

6. oil and gas extraction

7. livestock grazing

8. farming

9. recreation

10. How should they be managed? Who should be permitted to use the lands? Ongoing controversy…

11. Examples: • Northern Spotted Owl • Endangered species • Habitat: Old-growth forests Of pacific northwest

12. Versus: • Jobs and harvesting resources: the old-growth trees are of high commercial value

13. Should we “drill baby drill”???

14. ANWR

15. Some public lands are restricted in use • National Park System • Managed by the National Park Service (NPS) • First established National Park??? • Only camping, hiking, fishing, and boating (motorized cars/boats are allowed)

18. Yosemite

19. The Grand Canyon

21. Denali

23. Arches

24. Volcano

26. Carlsbad Caverns

28. Big Bend

29. Glacier

31. The Badlands

33. Great Smokey Mountains

36. Other public lands are very restricted – meant to be preserved in their natural condition • National Wilderness Preservation System • Established by the Wilderness Act (1964) • Managed by multiple agencies (BLM, USFWS, USFS, and NPS) • National Wild and Scenic Rivers (1968) • Non-motorized recreation ONLY

39. Types of Forests: • Old-growth: has not been cut/disturbed by human activity for hundreds of years. • Example: Redwood Forest

40. Second-growth: forest that has grown back after it had been cut/removed by human activities.

41. Since 1600, 90% of the virgin forests that once covered much of the lower 48 states have been cleared away.  Most of the remaining old-growth forests in the lower 48 states and Alaska are on public lands.  In the Pacific Northwest about 80% of this forestland is slated for logging.    • Global Deforestation Lecture, The University of Michigan: Global Change

43. Tree plantation or tree farm: • Monoculture (example: Christmas tree farm)

44. (example: apple orchard)

45. Types of Forest Management: • Even-aged: Maintaining trees at about the same age and size (tree plantation) • Goal: economically desirable species • Uneven-aged: Maintaining a variety of trees at many ages and sizes • Goal: sustainable production

46. Types of Tree Harvesting: • Selective cutting: medium or mature trees in uneven-aged stand cut singly or in small groups.

47. Shelterwood cutting: remove all mature trees in an area in a series of cuttings. • First cut: mature trees (mostly canopy trees) • Second cut: more mature canopy trees but leaves a few mature trees to “shelter” the young trees (which are shade tolerant) • Third cut: remove remaining mature trees now that the younger ones are growing to maturity

48. Seed-tree cutting: harvesting nearly all trees in one cutting, but leaving a few uniformly distributed seedlings.

49. Strip cutting: removes all trees in an area in a single cutting (in a strip)

50. Clear cutting: removes ALL trees in a single area. MOST devastating to an ecosystem; causes massive soil erosion if done on sloped land.