Sustaining Biodiversity: The Ecosystem Approach Chapter 9

Key Questions ■ What are the major threats to forest ecosystems? ■ How should we manage and sustain forests? ■ How should we manage and sustain grasslands? ■ How should we manage and sustain parks and nature reserves? ■ What is the ecosystem approach to sustaining biodiversity? ■ How can humans help sustain the Earth’s biodiversity? a

Human Impacts on Biodiversity ■ Human “footprint” ■ Disturbing the land - humans have disturbed % of Earth ■ Destruction of wetlands half world’s wetlands lost in past 100 yrs ■ Deforestation ■ Aquatic biodiversity - 27% coral reefs severely damaged- 75% fish are fished at or above limit ■ Premature extinctions - current extinction rate likely 1, ,000 times greater than before humans

What are the major threats to forest ecosystems? Section 9-1 Natural Capital Degradation: 2,000 per year

Support energy flow and chemical cycling Reduce soil erosion Absorb and release water Purify water & air Influence local and regional climate Store carbon Provide wildlife habitats Fuelwood Lumber Pulp to make paper Mining Livestock grazing Recreation Jobs- 1 of 4 people depend on forests for living Major Services of Forests Forests Ecological Services Economic Services Ecological services of world’s forests valued at $33.2 trillion per year!!! Value of ecological services much greater than value of economic services >>> Much greater than

Types of Forests Old-growth - not seriously disrupted for at least several hundred years Second-growth - results from secondary succession Tree plantation or tree farm - managed tract of uniformly aged trees of one or two species. Clear cut when commercially valuable, then replanted. Less diverse & less sustainable than old or 2nd

Types of Forest Management ■ Even-aged management (industry forestry) trees about same age and size- simplified tree plantation- 1-2 fast- growing species harvested on rotation cycle. EX: Clear cuttingEX: Seed tree method : In the seed-tree method, 2-12 seed trees per acre (5-30/ha) are left standing in order to regenerate the forest. EX: Shelter wood method : The method's objective is to establish new forest reproduction under the shelter of the retained trees. ■ Rotation cycles: years (temperate), 6-10 years (tropical) EX: Strip cutting (more sustainable) ■ Uneven-aged management - variety of species w/ range of ages & sizes. Goals: biodiversity, sustainable high quality timber EX: Selective cutting

Clear-cutting Reduces biodiversity Disrupts ecosystem processes Destroys and fragments some wildlife habitats Leaves moderate to large openings Increases soil erosion Increases sediment water pollution and flooding when done on steep slopes Eliminates most recreational value for several decades

Degradation of Forests from Logging Roads ■ Increased erosion and sediment runoff ■ Habitat fragmentation ■ Biodiversity loss ■ Pathways for pests, diseases, and invasive species ■ More accessible for humans Cleared plots for grazing Cleared plots for agriculture Highway

Trade-Offs Clear-Cutting Forests Advantages Disadvantages Higher timber yields Maximum economic return in shortest time Can reforest with genetically improved fast-growing trees Short time to establish new stand of trees Needs less skill and planning Best way to harvest tree plantations Good for tree species needing full or moderate sunlight for growth Reduces biodiversity Disrupts ecosystem processes Destroys and fragments some wildlife habitats Leaves moderate to large openings Increases soil erosion Increases sediment water pollution and flooding when done on steep slopes Eliminates most recreational value for several decades Tradeoffs of Clear-cutting Forests

© 2006 Brooks/Cole - Thomson Natural Capital Degradation Deforestation Decreased soil fertility from erosion Runoff of eroded soil into aquatic systems Premature extinction of species with specialized niches Loss of habitat for migratory species such as birds and butterflies Regional climate change from extensive clearing Releases CO 2 into atmosphere from burning and tree decay Accelerates flooding Harmful Effects of Deforestation ABOUT 46% OF WORLD’S FORESTS HAVE BEEN CUT DOWN IN THE LAST 60 YEARS

Surface and Crown Fires Ground fire: underground surface fire, common in northern peat bogs or when there is significant dead wood on forest floor (can be intense) Least intenseMore intense and destructive of life Mature trees & animals escape Help prevent more destructive fires Free mineral nutrients from decomposing litter Release seeds from cones Stimulate germination Help control diseases and insects Provide young tender vegetation to wildlife

Section 9-2 How should we manage and sustain forests?

Minimizing Forest Damage from Fire ■ Prescribed burning - reduce underbrush ■ Allow small fires in National Parks, forests & wilderness to burn (if people & property not threatened) ■ Defensible space- clear 200 feet around buildings

Healthy Forests Initiative Law? Read more about this! Online links. Effects of the Healthy Forests Initiative -Timber Co. allowed to take large/medium trees in Nat. Forests if they clear away smaller, fire-prone trees. Criticized by fire scientists (large tree most fire resistant, logging creates slash) Other problems: Allowing for cutting on basis of “fire reduction” allows decision- making process to avoid public input.

© 2006 Brooks/Cole - Thomson Solutions Sustainable Forestry Grow more timber on long rotations Rely more on selective cutting and strip cutting No clear-cutting, seed-tree, or shelterwood cutting on steeply sloped land No fragmentation of remaining large blocks of forest Sharply reduce road building into uncut forest areas Leave most standing dead trees and fallen timber for wildlife habitat and nutrient recycling Certify timber grown by sustainable methods Include ecological services of trees and forests in estimating economic value Sustainable Forestry Conserves biodiversity, water & soil resources Sustainable management intensive management of as little as 20% of world’s forests could meet current and future demand for commercial wood / fiber Combine aspects of a number of management techniques such as SELECTIVE CUTTING.

Kenaf Yields more paper pulp per land area than tree farms & require less pesticides & herbicides. Holds potential to greatly reduce pressure to cut trees for paper. Also hemp.

Tropical Deforestation ■ Rapid and increasing – over 11 football fields lost per minute (Nature Conservancy quotes 1 field per SECOND), half of historical rainforests have been lost—most since 1950 ■ Loss of biodiversity at least half world’s terrestrial species live in tropical forests (on 6% of earth’s land) ■ Deforestation for croplands, logging and ranching ■ Problems measuring deforestation - satellite images difficult, countries misreport, varying definitions ■ Causes of tropical deforestation = pop. Growth, poverty, gov. subsidies, debt, failure to value ecological services ■ Burning: contributes CO 2 to global warming ■ Possible solutions - prevention & restoration - see next slide

Protect most diverse and endangered areas Educate settlers about sustainable agriculture and forestry Phase out subsidies that encourage unsustainable forest use Add subsidies that encourage sustainable forest use Protect forests with debt-for-nature swaps, conservation easements, and conservation concessions Certify sustainably grown timber Reduce illegal cutting Reduce poverty Slow population growth Reforestation Rehabilitation of degraded areas Concentrate farming and ranching on already-cleared areas Restoration Prevention Solutions Sustaining Tropical Forests Protecting Tropical Forests

How should we manage and sustain grasslands? Section 9-3

Rangelands & Overgrazing ■ Rangelands = unfenced supply vegetation, for grazing (grass-eating) and browsing (shrub- eating) animals. ■ Grasslands ecological services; soil formation, erosion control, nutrient cycling, storage of atmospheric carbon dioxide in biomass, and maintenance of biodiversity. ■ Overgrazing: caused a loss in productivity in as much as 20% of the world’s rangeland.

We can manage rangelands more sustainably ■ Control the number of grazing animals ■ Rotational grazing ■ Provide supplemental feed ■ Suppress the growth of unwanted invader plants by use of herbicides, mechanical removal, or controlled burning or use controlled, short-term trampling by large numbers of livestock.

Restoration of a Stream Bank Area restored in 10 years after banning grazing and off-road vehicles.

Ecological Restoration “process of repairing damage caused by humans to the biodiversity & dynamics of natural ecosystems” ■ Restoration, rehabilitation and replacement ■ Creating artificial ecosystems Principles of Ecological Restoration: 1. Mimic nature 2. Recreate important ecological niches 3. Rely on pioneer, keystone and foundational species and natural ecological succession 4. Control or remove nonnative species Accomplishments in Costa Rica: from a high deforester, to very low. Present forest cover at 50% of nation (up from 21% in 1987)

Section 9-4 How should we manage and sustain parks and nature reserves?

Types of US Public Lands (35% of US is public land—large % in Alaska) ■ Multiple-use lands: National Forest System; Natural Resource Lands (BLM) ■ Moderately restricted-use lands: Natural Wildlife Refuges ■ Restricted-use lands: National Park System (58 parks); Natural Wilderness Preservation System

National parks and preservesNational forests US Federal Public Lands +Much in Alaska! (and Xs) National wildlife refuges

Managing US Public Lands principles of public land use Conservationists Developers Protecting biodiversity is a primary goal No subsidies or tax breaks for use of resources Public should get fair compensation for use Users are responsible for environmental damage Alternative views from developers and industry Sell public lands / less than market value Slash funding for regulation Cut old growth forests in national forests and replace with tree plantations Open all public land to oil, mining, off- roading and commercial development Eliminate Nat. Park Service, mine without royalties, repeal Endangered Species Act, …

Managing US National Forests ■ Status of US forests- 30% of USA forested, more wood grown than cut more forests now than in 1920 (old growth forests decreasing) ■ Importance of national forests ■ Management of forests ■ Lost revenue from timber sales - timber sales from US federal land lost taxpayer money in 97 of past 100 years ■ Controversies of logging national forests - 10x more $ and 7x more jobs added to economy by using national forests for recreation, hunting & fishing ■ Tree-free fibers and paper- agricultural residues, kenaf & industrial hemp

Fig. 8-17, p. 168 Trade- Offs Advantages Disadvantages Logging in U.S. National Forests Helps meet country’s timber needs Cut areas grow back Keeps lumber and paper prices down Provides jobs in nearby communities Promotes economic growth in nearby communities Provides only 4% of timber needs Ample private forest land to meet timber needs Has little effect on timber and paper prices Damages nearby rivers and fisheries *Recreation in national forests provides more local jobs and income for local communities than logging Decreases recreational opportunities Logging in U.S. National Forests

Global Outlook: Threats to National Parks ■ Too little protection ■ Illegal wood collection, logging, poaching, and mining ■ Too little money to support the parks ■ Too small to sustain biodiversity ■ Invasions from nonnative species ■ Too many visitors to US national parks ■ Traffic jams and air pollution in US parks ■ Underpaid park officials ■ Harm from dirt bikes, dune buggies, and snowmobiles

Wilderness Protection in US ■ Mostly a losing battle ■ Wilderness Act of 1964 ■ National Wilderness Preservation System ■ Protected wilderness increased 10 fold since 1970 ■ Most protected areas are small (4.6% of US land is protected as wilderness) ■ Only 81 of 233 distinct US ecosystems are protected ■ Efforts to expand wilderness areas in the US

Section 9-5 What is the ecosystem approach to sustaining biodiversity?

The Ecosystem ApproachThe Species Approach Tactics Protect habitat areas through private purchase or government action Eliminate or reduce populations of nonnative species from protected areas Manage protected areas to sustain native species Restore degraded ecosystems Tactics Legally protect endangered species Manage habitat Propagate endangered species in captivity Reintroduce species into suitable habitats Strategy Preserve sufficient areas of habitats in different biomes and aquatic systems Strategy Identify endangered species Protect their critical habitats Goal Protect populations of species in their natural habitats Goal Protect species from premature extinction Human Impacts on Biodiversity

Biodiversity Hot Spots especially rich in plant and animal species: contains at least 1500 native plant species in great danger of species extinction: has lost at least 70% of its original habitat a unique area with species found nowhere else.

Animation Biodiversity hot-spots interaction.

Section 9-6 How can we help to sustain aquatic biodiversity?

General Patterns of Marine Biodiversity ■ Greatest biodiversity in coral reefs, estuaries, and deep-sea floor ■ Biodiversity is higher near coasts than open sea ■ Biodiversity is higher on the ocean bottom than the surface ■ Loss and degradation of habitat is greatest threat ■ Damage to coral reefs and other habitats ■ Dredging / trawler operations destroy bottom habitats ■ Overfishing ■ Premature extinction Human Impacts

Degradation of the Ocean Floor

The collapse of Canada’s 500-year-old Atlantic cod fishery

Why Is It Difficult to Protect Marine Biodiversity? ■Coastal development ■Unseen pollution ■Lack of protection in international waters ■“Tragedy of the Commons”

Major commercial fishing methods

Biodiversity Seminar- Additional Question ■Identify specific fishing practices that are considered unsustainable. Discuss sustainable alternatives and their long- term economic & environmental viability.

Fig. 8-30, p. 181 Fishery Regulations Set catch limits well below the maximum sustainable yield Improve monitoring and enforcement of regulations Economic Approaches Sharply reduce or eliminate fishing subsidies Charge fees for harvesting fish & shellfish from publicly owned offshore waters Certify sustainable fisheries Protected Areas Establish no-fishing areas Establish more marine protected areas Rely more on integrated coastal management Consumer Information Label sustainably harvested fish Publicize overfished and Bycatch Use wide-meshed nets to allow escape of smaller fish Use net escape devices for seabirds and sea turtles Ban throwing edible and marketable fish back into the sea Aquaculture Restrict coastal locations for fish farms Control pollution more strictly Depend more on herbivorous fish species Nonative Invasions Kill organisms in ship ballast water Filter organisms from ship ballast water Dump ballast water far at sea and replace with deep-sea water Managing Fisheries - Solutions

What Can We Do? EO Wilson’s Priorities ■ Preserve world’s biological “hot spots” ■ Save the old-growth forest ■ Map world biodiversity so we know what we have ■ Identify and protect marine “hot spots” ■ Protect and restore lakes and streams ■ Ensure the full range of ecosystem types in the conservation strategy ■ Make conservation profitable ■ Initiate worldwide ecological restoration projects Two big ideas ■ Value and Protect