Sustaining Terrestrial Biodiversity: The Ecosystem Approach

1. Sustaining Terrestrial Biodiversity: The Ecosystem Approach G. Tyler Miller’s Living in the Environment 13th Edition Chapter 23

2. Key Concepts • Human land use • Types and uses of US public lands • Forests and forest management • Implications of deforestation • Management of parks • Establishment and management of nature preserves • Importance of ecological restoration

3. Land Use in the World Fig. 23-2 p. 595

4. Land Ownership and Use in the United States Rangeland and pasture 29%

5. Types of US Public Lands • Multiple-use lands: National Forests; National Resource Lands • Moderately-restricted use lands: National Wildlife Refuges • Restricted-use lands: National Park System; National Wilderness Preservation System

6. US Public Lands Fig. 23-4 p. 596

7. Managing US Public Land • Primary goal to protect biodiversity and ecological functions • No subsidies or tax breaks for use • Public should get fair compensation • Users held responsible for actions (Aldo Leopold’s Land-Use Ethic)

8. Managing and Sustaining Forests Ecological Importance of Forests • Food webs and energy flow • Water regulation • Influence local-regional climate • Numerous habitats and niches • Air purification • Carbon sequestration

9. Managing and Sustaining Forests Economic Importance of Forests • Fuelwood (50% of global forest use) • Industrial timber and lumber • Pulp and paper • Medicines • Mineral extraction • Recreation

10. Forest Structure Layers of Biodiversity Fig. 23-9 p. 601

11. Types of Forests • Old-growth (frontier) forests • Second-growth forests • Tree farms/plantation Fig. 23-18 p. 609

12. Forest Management • Rotation cycle • Even-aged management • Industrial forestry • Uneven-aged management • Improved diversity • Sustainable production • Selective cutting • Multiple-use

13. Management Strategies Fig. 23-11 p. 601 Short Rotation Cycle Fig. 23-12 p. 602

14. Logging Roads result in • increased erosion and runoff • habitat fragmentation • pathways for exotic species • accessibility to humans Fig. 23-13 p. 602

15. Harvesting Trees Trees can be harvested individually from diverse forests (selective cutting), an entire forest can be cut down (clear cutting), or portions of the forest is harvested (e.g. strip cutting).

16. Tree Harvesting Methods • Selective cutting • high grading • Shelterwood cutting • Seed-tree cutting • Clearcutting • Strip cutting Fig. 23-14 p. 603

17. What is happening to the world’s forests? Forests are renewable resources as long as the rate of cutting and degradation does not exceed the rate of re-growth.

18. Sustainable Forestry • Longer rotations • Selective or strip cutting • Minimize fragmentation • Improved road building techniques • Certified sustainable grown(See Solutions p. 598)

20. Pathogens Fungal Diseases • Chestnut blight • Dutch elm disease Insect Pests • Bark beetles • Gypsy moth

21. Fire(intermittent natural fires set by lightening) Depending on their intensity, fires can benefit or harm forests.

22. Surface/Ground Fire • Burn away flamable ground material • Release mineral nutrients • Increase activity of nitrogen-fixing bacteria • Stimulate germination of some seeds • Help control pathogens and insects

23. Crown Fire • Destroys most vegetation • Kills wildlife • Increases soil erosion

24. Fire Management • Prevention • Prescibed burning • Presuppression • Suppression For more than 70 years, firefighting has been a high priority for forest managers.

25. Fire Management “Only you can prevent forest fires.” • In 1989, the US spent over $1 billion and lost 33 lives in efforts to stop forest fires. Smokey the Bear

26. Forest Resources and Management in the United States • Sustained yield • potentially renewable resources should not be harvested or used faster than they can be reproduced • Multiple Use • Wildlife, timber harvests, watershed protection, recreation, livestock grazing • Only 3% of timber harvest comes from national forests • Substitutes for tree products • Tree-free fibers

27. Solutions: Reducing Demand for Harvest Trees Tree harvesting can be reduced by wasting less wood and making paper and charcoal fuel from fibers that do not come from trees. Kenafis a promising plant for paper production.

28. TROPICAL DEFORESTATION Large areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rate.

29. TROPICAL DEFORESTATION At least half of the world’s terrestrial plant and animal species live in tropical rain forests. Large areas of tropical forest are burned to make way for cattle ranches and crops.

30. Tropical Deforestation Issues Rapid and increasing deforestation 0.6-2.0% per year Loss of biodiversity Madagascar Case Study Cultural extinction Should we be protecting the rights of the earth’s remaining indigenous cultures? Unsuitable agriculture and ranching Clearing for cash crop plantations Increasing forest fires Commercial logging Fuelwood

31. Bromeliad Exploitive government policies Rapid population growth Blue morpho butterfly Poverty Orchid Toucan Scarlet macaw Secondary Causes: Golden lion marmoset Roads Unsustainable peasant farming Logging Flooding from dams Cattle ranching Mining Cash crops Oil drilling Tree plantations Primary Causes

32. Reducing Tropical Deforestation • Identification of critical ecosystems • Reducing poverty and population growth • Sustainable tropical agriculture • Encourage protection of large tracts • Less destructive harvesting methods • Debt-for-nature swaps

33. Debt-for-Nature Swaps Participating countries act as custodians for protected forest reserves in return for foreign aid or debt relief

34. The Fuelwood Crisis • Planting fast-growing fuelwood plants • Burning wood more efficiently (new stove designs) • Switching to other fuels (root-fuel plants) Fig. 23-25 p. 618

35. U.S. National Parks Goals To preserve nature in parks To make nature more available to the public Sometimes these two goals are in conflict with one another.

36. Managing and Sustaining National Parks - Threats Most parks too small to maintain biodiversity Invasion of exotic species a threat Limited Funding Popularity a major problem Traffic jams and air pollution Visitor impact Nearby human activity mining, logging, grazing, power plants, development

37. Managing and Sustaining National Parks - Solutions Principle of natural regulation parks will be self sustaining if left alone considered a misguided policy Suggestions require integrated management plan increase budgets locate commercial facilities outside park boundaries survey conditions and types of wildlife raise entrance fees limit visitors increase pay for park rangers encourage volunteers encourage individual and corporate donations

38. Managing Nature Reserves:Establishment and Design Should include some moderate disturbances Design should sustain natural ecological processes Round Large Heterogeneous Buffer zones

39. Model Nature Reserves contains a protected inner core surrounded by two buffer zones that people can use for multiple use.

40. Managing Nature Reserves:Establishment and Design Gap analysis Maps of topography, vegetation, hydrology, land ownership, and existing nature reserves Estimates of geographic distribution of plants and animals by regions Superimpose species distribution maps on vegetation maps to determine unprotected areas, gaps with high species diversity, unprotected pockets of rare species.

41. Managing Nature Reserves Protect most important areas Biodiversity hotspots Wilderness areas Protection of undeveloped lands from human exploitation by legally setting them aside. Wilderness – areas “of undeveloped land affected primarily by the forces of nature, where man is a visitor and does not remain”

42. 34 hotspots identified by ecologists as important and endangered centers of biodiversity.

43. Ecological Restoration What is here? What will nature permit us to do here? What will nature help us to do here? Restoration Return to pre-existing condition Mitigation– protect, restore, or create a similar ecosystem of roughly the same size Rehabilitation Restore some of the natural species and ecosystem functions (i.e. remove pollutants) Replacement Replacing a degraded ecosystem with another type of ecosystem

44. WHAT CAN WE DO? Eight priorities for protecting biodiversity: Take immediate action to preserve world’s biological hot spots. Keep intact remaining old growth forests. Complete mapping of world’s biodiversity for inventory and decision making. Determine world’s marine hot spots.

45. WHAT CAN WE DO? Concentrate on protecting and restoring lake and river systems (most threatened ecosystems). Ensure that the full range of the earths ecosystems are included in global conservation strategy. Make conservation profitable. Initiate ecological restoration products to heal some of the damage done and increase share of earth’s land and water allotted to the rest of nature.