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What are the Major Types of U.S. Public Lands?. Multiple Use LandsNational Forest SystemNational Resource Lands. Moderately Restricted-Use Lands National Wildlife RefugesRestricted-Use Lands National Park SystemNational Wilderness Preservation System. How Should U.S. Public Lands Be Managed?.
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1. Chapter 23 Lecture Sustaining Aquatic Biodiversity
2. What are the Major Types of U.S. Public Lands? Multiple Use Lands
National Forest System
National Resource Lands.
Moderately Restricted-Use Lands
National Wildlife Refuges
Restricted-Use Lands
National Park System
National Wilderness Preservation System
3. How Should U.S. Public Lands Be Managed? The four following principles from environmental economists and free-market economists: (Aldo Leopolds Land Ethics)
Protect biodiversity, habitats, and ecological functioning should be number 1 goal.
No one should receive subsidies or tax breaks for using or extracting resources on public lands.
American people deserve fair compensation for the use of their property.
All users of extractors of resources on public lands should be fully responsible for any environmental damage caused.
4. How Should U.S. Public Lands Be Managed? Economists, developers, and resource extractors view public lands in the following ways:
Their usefulness in providing mineral, timber, and other resources
The ability to increase short-term economic growth
Encourage the US Congress to pass a variety of anti-environmental laws
5. What Are the Major Types of Forests? Forests with 50% or more tree cover occupies about 32% of the earths land surface
Can be classified as:
Old-Growth Forests uncut forests or regenerated forests that have not been seriously disturbed by human activities or nature disasters
Second-Growth Forests stands of trees from areas where trees were once removed by human activities such as clear cutting or natural forces such as fire, hurricanes, or volcanic eruptions.
Tree Plantations managed tracts with uniformly aged tress of one species.
6. What Are the Major Types of Forest Management? Even-aged Management involves maintaining trees in a give stands at about the same size and age.
Uneven aged Management involves the maintaining of a variety of species in a stand at many ages and sizes to foster natural regeneration.
Goals of Biological diversity
Long-term sustainable production
Selective cutting of individual or mature trees
Multiple use of the forest
7. How Are Trees Harvested? Build roads for access and timber removal:
Increased erosion and sediment runoff
Habitat fragmentation and biodiversity loss
Exposure of forests to invasion by nonnatives
Opening of once-inaccessible forests to farmers, miners, etc.
Logging roads cannot be protected as wilderness.
8. How Are Trees Harvested? Selective cutting cut singly or in small groups
Reduced crowding
Encourages growth of younger trees
Maintains an uneven-aged stand or different species.
Allows natural regeneration from the surrounding trees
Can be used to remove diseased tress
Can protect the site for soil erosion and wind damage
Allows a forest to be used for multiple purposed.
High-grading the cutting and removing of only the largest and best.
Reduces the forest canopy
Causes the forest floor to become warmer, drier, and more flammable.
Increases erosion of the forests thin and nutrient-poor soil
9. How Are Trees Harvested? Shelterwood Cutting - removes all mature trees in two to three cuttings over a period of ten yeas.
Seed-tree Cutting harvests nearly all a stands trees in one cutting, leaving a few uniformly distributed seed-producing trees
Clear-cutting removes all of the trees from an area in a single cutting.
Strip-cutting clear-cutting a strip of trees along the contour of the land to allow natural regeneration within a few years
10. Positive and Negative Sides of Clear Cutting POSITIVE:
Increases timber yield per hectare
Permits reforesting with genetically improved stocks
Shortens time to establish a new stand of trees
Takes less skill and planning
Maximum economic return in the shortest time.
If done carefully and responsibly is the best way to harvest tree plantations for some species.
NEGATIVE:
Leaves moderate to large forest openings
Eliminates most recreational value for decades
Disrupts biodiversity; destroys and fragments wildlife habitat
Makes nearby trees more vulnerable to being blown down
Leads to severe soil erosion, sediment water pollution, and flooding on steep slopes.
11. What Is Happening to the Worlds Forests? Forests are renewable resources as long as the rate of cutting and degradation does not exceed the rate of regrowth.
How Can Forests Be Managed More Sustainably?
Grows timber on long rotations
Emphasizes selective cutting, strip cutting, not clear-cutting on steep slopes
Minimize fragmentation
Reduce road building in uncut forest areas
Use road building and logging methods that minimize soil erosion and compaction.
Leave most standing dead trees and fallen timber
Timber grown by sustainable methods certified and labeled by outside certifying groups
Includes the estimated ecological services in economic value.
12. How Can Pathogens and Insects Affect Forests Ways to reduce the impact of tree diseases and of insects on forests
Preserve biodiversity
Ban imported timber
Remove infected and infested trees, clearing, burning
Treating diseased trees with antibiotics
Developing tree species that are disease-resistant
Applying pesticides
Using integrated pest management.
13. How Can Fires Affect Ecosystems? Fires can be important:
Maintain the vegetations of many ecosystems at a certain stage of ecological succession; fires burn away the low-lying vegetation and small trees; a burst of new vegetation follows.
Surface fires usually burn only undergrowth and leaf litter on the forest floor. Kill seedlings and small trees but spare most mature trees and allow most wild animals to escape.
Crown fires extremely hot fires might start on the ground, but eventually burn whole trees and leap from top to top.
14. How Can We Protect Forests From Fire? Prevention
Requiring burning permits
Closing all parts of a forest and camping during periods of drought and high fire danger
Educating the public
Smokey Bear! prevent forest fires, save lives, prevent billions in losses
Prescribed burning setting controlled ground fires
Presuppression early detection and control of fires
Suppression fighting fires once they have started.
15. How Do Air Pollution and Climate change Threaten Forests? At high elevations and those downwind from urban and industrial centers are exposed to a variety of air pollutants that can harm trees
Reduce emissions of the offending pollutants
Regional climate change brought about by global warmning
Increase the threat of forest fires in areas that may get less precipitations
Cause some types of tree species to die out in some areas.
16. Why Should We Care About National Forests? Economic
Supply timber
Serve as grazing lands
Provide minerals, oil, and natural gas
Contain network of roads
Ecological
o Provide habitat for almost 200 threatened and endangered species
o Principle habitats for pollinator species
o Provide some of the cleanest drinking water.
Recreational
Recreation, hunting, fishing
17. How Should U.S. National Forests Be Managed? Sustainable Yield trees cant be harvested or used faster than they are replenished
Multiple Use each of the forests should be managed for a variety of uses such as sustainable timber harvesting, recreation, livestock grazing, watershed protection, and wildlife.
In 2001, Bush increased the sale of timber in national forests by 40%, moved to block road construction in roadless areas of the national forest; eliminated the requirement that the forest service manage national forests to protect the viability of wildlife and ecological sustainability. Created the idea of charter forests.
18. Battle Between Environmentalists and Timber Companies Environmentalists:
Timber-cutting program Loses Money:
Logging in national forests causes more harm than good to local communities near such forests; Communties relying on national forest timber sales experience economic slumps.
Costs the taxpayers in logging subsidies and cleaning of pollutions; It would save taxpayers money.
Only provides about 3% of the countries wood is from National Forests
Ample private forestland is available to meet the countries demand for wood
Below costs is not good for other forests and has little effect on the consumer
Recreation in national forests provides more jobs.
Timber Companies say:
Helps satisfy the countrys demand for food
Provides cheap timber that benefits consumers
Improves forest health, fires
Provides jobs and stimulates economic growth.
19. How Can We Cut Fewer Trees by Using Wood More Efficiently? 60% of the wood consumed is wasted:
o inefficient use of construction materials
o excess packaging
o Overuse of junk mail
o Inadequate paper recycling
Failure to reuse wooden shipping containers
o Packaging (50%)
o Writing and printing (30%)
o Newsprint (12%)
o Paper tissues and towels (8%)
Only 3% of softwood production comes from national forests
20. How Can We Cut Fewer Trees by Making Paper from Tree-Free Fibers? Tree-free fibers:
From agricultural residues from crops
From fast growing crops
Account for 7% of the worlds fiber supply for paper
less than 1% in the US
China uses tree-free pulp makes 60% of paper
Made from kenaf in the US
3 5X the cost however, supply and demand
21. Why Is It Difficult to Determine Deforestation? Interpretation of satellite images
Different ways of defining forests
Political and economic factors
Why Should We Care About Tropical Forests?
Economic and ecological services
Their instrumental values
Chemicals
Uses
22. Case Study: Madagascar 85% of the plant and animals species re endemic species unique to the island
Lost of habitat due to slash and burn agriculture and rapid population growth
Many species face extinction
Large erosion
23. What Is Cultural Extinction? Indigenous cultures who used the land sustainably are vanishing
This is an irreplaceable loss of ecological knowledge and cultural diversity
They know how to live sustainably
They know which plants are useful as food and medicines.
24. Solutions to Deforestation and Degradation Solutions:
New settlers who know how to practice small-scale sustinable agriculture and forestry
Debt for Nature Swaps
Conservation Easements
Conservation Concessions
International System for Evaluating Timber produced by sustainable methods
Gentler methods for harvesting trees
National and global efforts to reforest and rehabilitate
25. Fuelwood Crisis Developing countries use wood to meet their energy needs
They have not had enough to meet their needs
They burn charcoal because it is lighter and cheaper
They must travel far distances, expensive, more disease, burn dung and crop residues
Solutions:
Plant more fast growing fuelwood trees
Switch to other fuels (root-fuel plants)
26. How are Parks Threatened? Only 1% of the parks in developing countries receive protections - become paper parks
Popularity
Lack of Funds
Lack of law enforcement
Suffer from nonnative specie
Nearby human activity threatens wildlife and recreational values
27. How Can Management of US Parks Be Improved? Currently under the principle of Natural Regulation - managed as if they are wilderness ecosystems that can adapt and sustain themselves.
Goals and Ideas:
Preserve nature
Make parks available to the public, but limit visitors and raise entry fees
Require integrated management plans for parks
Increase the budget - more maintenance and repairs, more park rangers at higher pay
Encourage donations, ask for volunteers
Provide transportation
Give private concessionaries
28. What Principles Should Be Used to Establish and Manage Nature Reserves? Ecosystems are rarely stable
Ecosystems and communities that experience fairly frequent but moderate disturbances have the greatest diversity of species
We should view most at habitat islands.
29. How Should Nature Reserves Be Designed? Shape - Circular or Elongated?
Single Large or Several Small Reserves?
Heterogenous or Homogeneous?
Isolated or Connected
What about Buffer Zones?
30. What is Gap Analysis? Gap Analysis - determines whether existing networks or nature reserves provide enough protection for native plant and animal species.
Maps of topography
Databases of biological information
Superimpose the species data onto the maps
Use this information to close gaps
Conservation Gaps - where there is a lack of adequate protection.
31. What Areas Should Receive Top Priority for Establishing Reserves? 25 Hot Spots
Mostly tropical forests
Contain 60% of the biodiversity
32. Wilderness - Why Preserve It? Wilderness - areas of undeveloped land affected primarily by the forces of nature, where man is a visitor who does not remain.
Why preserve?
Beauty of nature!
Just to know it is there is comforting
Centers of evolution
Undisturbed areas
A natural laboratory
Wild species have a right to exist and play their roles in earth.
33. Fixing Ecosystems Restoration - trying to return it to its predegraded state
Let nature do most of the work
Remove pollutants, add nutrients, add topsoil, remove nonnative species
Reintroduce species
Prevention from further damage
Monitor area
Difficulties include
Lack of knowledge about previous composition
Changes in climate
Ecosystem is changing
Rehabilitation - an attempt to restore some of the degraded systems species and ecosystem functions.
Replacement - replace a degraded ecosystem
Create Artificial Ecosystems
34. What Are The Next Steps? Preserve hot spots
Keep forests intact
Cease all logging of old-growth forests
Concentrate on protecting lakes and river systems
Determine marine hot spots
Continue to map the worlds biodiversity
Make conservation profitable