© Cengage Learning 2015 LIVING IN THE ENVIRONMENT, 18e G. TYLER MILLER SCOTT E. SPOOLMAN © Cengage Learning Sustaining Terrestrial Biodiversity: Saving Ecosystems and Ecosystem Services

© Cengage Learning 2015 Suffered widespread deforestation Still harbors great biodiversity –Microclimates provide variety of habitats –More than 25% of its land is nature reserves and national parks Government pays landowners to restore forests Core Case Study: Costa Rica – A Global Conservation Leader

© Cengage Learning 2015 Fig. 10-1, p. 218

© Cengage Learning 2015 Forest ecosystems provide ecosystem services far greater in value than the value of raw materials obtained from forests Chief threats to forest ecosystems –Unsustainable cutting and burning of forests –Diseases and insects –Projected climate change 10-1 What Are the Major Threats to Forest Ecosystems?

© Cengage Learning Old-growth or primary forest (about 36%) –Uncut not disturbed for several hundred years –Reservoirs of biodiversity 2. Second-growth forest –Results from secondary succession Forests Vary in Their Age, Make-Up, and Origins

© Cengage Learning Tree plantation (tree farm, commercial forest) –Managed forest containing only one or two species of trees that are all of the same age. –Usually harvested by clear-cutting and replanted in a cycle

Fig. 10-2, p. 219

© Cengage Learning 2015 Fig. 10-3a, p yrs Weak trees removed Clear cut 30 yrs Years of growth 15 yrs Seedlings planted 5 yrs10 yrs

© Cengage Learning 2015 Fig. 10-3b, p. 219

© Cengage Learning 2015 Store atmospheric carbon Provide habitats Influence local and regional climate Provide raw materials Provide health benefits –Medicines derived from plant species Forests Provide Important Economic and Ecosystem Services

Fig. 10-4, p. 220 Forests Support energy flow and chemical cycling Fuelwood Ecological Services Economic Services Natural Capital Reduce soil erosion Lumber Absorb and release water Pulp to make paper Purify water and air Mining Influence local and regional climate Livestock grazing Store atmospheric carbon Recreation Provide numerous wildlife habitats Jobs

© Cengage Learning 2015 One of the world’s largest industries 1. Selective cutting –Intermediate-age or mature trees are cut singly or in small groups 2. Clear-cutting –All trees in an area are removed 3. Strip cutting –Clear-cutting in strips There Are Several Ways to Harvest Trees

New highway Old growth Cleared plots for agriculture Highway Cleared plots for grazing Fig. 10-5, p. 221

Stepped Art (b) Clear-cutting Muddy stream Uncut Cut 1 year ago Dirt road Cut 3–10 years ago Uncut Clear stream (a) Selective cutting (c) Strip cutting Clear stream Fig. 10-6, p. 222

Fig. 10-7, p. 222

© Cengage Learning 2015 Fig. 10-8, p. 222 Trade-Offs Clear-Cutting Forests AdvantagesDisadvantages Higher timber yieldsReduces biodiversity Destroys and fragments wildlife habitats Maximum profits in shortest time Can reforest with fast-growing trees Can lead to water pollution, flooding, and erosion, especially on steep slopes

© Cengage Learning online/play/7605/Forests-For-Peoplehttp:// online/play/7605/Forests-For-People Forest For People

© Cengage Learning 2015 Two types of fires: 1. Surface fires –Usually burn leaf litter and undergrowth –Provide many ecological benefits 2. Crown fires –Extremely hot – burns whole trees –Can destroy vegetation, kill wildlife, increase soil erosion Fire, Insects, and Climate Change Can Threaten Forest Ecosystems

© Cengage Learning 2015 Additional threats: 1. Introduction of foreign diseases and insects –Accidental or deliberate 2. Global warming –Rising temperatures and increased drought –Trees more susceptible to diseases and pests –Drier forests –> more fires –More greenhouse gases Fire, Insects, and Climate Change Can Threaten Forest Ecosystems (cont’d.)

© Cengage Learning 2015 Fig. 10-9, p. 223

© Cengage Learning 2015 Deforestation –Temporary or permanent removal of large expanses of forest for agriculture, settlements, or other uses –Tropical forests Especially in Latin America, Indonesia, and Africa –Boreal forests Especially in Alaska, Canada, Scandinavia, and Russia Almost Half of the World’s Forests Have Been Cut Down

© Cengage Learning 2015 Encouraging news –Recent increases in forest cover –Due to: Reforestation of cleared areas and abandoned croplands Tree plantations Almost Half of the World’s Forests Have Been Cut Down (cont’d.)

© Cengage Learning 2015 Fig , p. 223

© Cengage Learning 2015 Fig , p. 224

© Cengage Learning 2015 Forests of the eastern United States decimated between 1620 and 1920 Grown back naturally through secondary ecological succession in the eastern states Biologically simplified tree plantations –Reduce biodiversity and deplete nutrients from soil Case Study: Many Cleared Forests in the United States Have Grown Back

© Cengage Learning 2015 Majority of loss since 1950 –Mostly in Africa, Southeast Asia, South America –Clearing trees can accelerate climate change Drier climate –Risk of larger and more frequent forest fires Ecological tipping point –Forest cannot grow back Tropical Forests are Disappearing Rapidly

© Cengage Learning 2015 Fig , p. 225

© Cengage Learning 2015 Various causes –Population growth –Poverty of subsistence farmers –Ranching –Lumber –Plantation farms – palm oil Begins with building of roads Many forests burned Causes of Tropical Deforestation Are Varied and Complex

© Cengage Learning 2015 We can sustain forests by: –Emphasizing the economic value of their ecosystem services –Removing government subsidies that hasten their destruction –Protecting old-growth forests –Harvesting trees no faster than they are replenished –Planting trees 10-2 How Should We Manage and Sustain Forests?

Solutions: Sustainable Forestry Fig , p. 227

© Cengage Learning 2015 Certify sustainably produced forest products Use more sustainable logging practices in tropical forests Phase out government subsidies We Can Manage Forests More Sustainably

© Cengage Learning 2015 The U.S. Smokey Bear educational campaign –Successfully prevented many forest fires, however has inadvertently convinced the public that forest fires are bad increasing the risk of crown fires. We Can Improve the Management of Forest Fires

© Cengage Learning 2015 Other strategies to manage forest fires: 1. Prescribed fires/burns –Set small, contained surface fires to remove flammable small trees and underbrush. 2. Allow fires on public lands to burn 3. Protect houses and buildings in fire- prone areas by thinning trees and other vegetation. 4. Thin forests vulnerable to fire We Can Improve the Management of Forest Fires

© Cengage Learning 2015 Improve the efficiency of wood use –60% of U.S. wood use is wasted Make tree-free paper –Kenaf –Hemp We Can Reduce the Demand for Harvested Trees

Solutions: Fast-Growing Plant: Kenaf Fig , p. 228

© Cengage Learning 2015 How is Haiti an example of an ecological disaster? Possible solutions –Establish small plantations of fast-growing fuelwood trees and shrubs –Burn wood more efficiently –Solar or wind-generated electricity –Burn garden waste Case Study: Deforestation and the Fuelwood Crisis

© Cengage Learning 2015 Fig , p. 229

© Cengage Learning Debt-for-nature swaps/conservation concessions –Protect forests in return for financial aid 2. Crack down on logging 3. End subsidies 4. Plant trees There Are Several Ways to Reduce Tropical Deforestation

Fig , p. 230 Solutions Sustaining Tropical Forests PreventionRestoration Protect the most diverse and endangered areas Encourage regrowth through secondary succession Educate settlers about sustainable agriculture and forestry Subsidize only sustainable forest use Rehabilitate degraded areas Protect forests through debt-for-nature swaps and conservation concessions Certify sustainably grown timber Concentrate farming and ranching in already-cleared areas Reduce poverty and slow population growth

© Cengage Learning 2015 Forests under fire: cdbu5Q Forests Under Fire

© Cengage Learning 2015 We can sustain the productivity of grasslands by: –Controlling the numbers and distribution of grazing livestock –Restoring degraded grasslands 10-3 How Should We Manage and Sustain Grasslands?

© Cengage Learning 2015 Rangelands –Unfenced grasslands in temperate and tropical climates that provide forage for animals Pastures –Managed grasslands and fenced meadows used for grazing livestock Some Rangelands Are Overgrazed

© Cengage Learning 2015 Overgrazing of rangelands –1. Reduces grass cover –2. Leads to erosion of soil by water and wind –3. Soil becomes compacted –4. Enhances invasion of plant species that cattle won’t eat Some Rangelands are Overgrazed (cont’d.)

© Cengage Learning 2015 Fig , p. 231

© Cengage Learning Rotational grazing –Cattle moved around 2. Fence damaged areas 3. Suppress growth of unwanted plants –Expensive: Herbicides & controlled burning –Cheap: trampling by livestock We Can Manage Rangelands More Sustainably

© Cengage Learning 2015 Fig , p. 232

© Cengage Learning 2015 American southwest population surge since 1980 Land trust groups – conservation easements Reduce the harmful environmental impact of herds –Operate ranch more economically and sustainably Case Study: Grazing and Urban Development the American West

© Cengage Learning 2015 Sustaining biodiversity will require: –More effective protection of existing parks and nature reserves –The protection of much more of the earth’s remaining undisturbed land area 10-4 How Should We Manage and Sustain Parks and Natural Reserves?

© Cengage Learning 2015 Worldwide – 6600 national parks Parks in less-developed countries –Greatest biodiversity of all parks in world –Only 1% protected against illegal: Animal poaching Logging and mining National Parks Face Many Environmental Threats

© Cengage Learning 2015 There are 58 major national parks in the U.S. The biggest problem may be popularity Other problems include: –Nonnative species –Poaching –Commercial development –Park maintenance Case Study: Stresses on U.S. Public Parks

Grand Teton National Park Fig , p. 234

© Cengage Learning 2015 Currently less than 13% of earth’s land is protected Conservationists’ goal – protect 20% Nature Reserves Occupy Only a Small Part of the Earth’s Land

© Cengage Learning 2015 Size and design of protected area is important –Buffer zone Strictly protecting inner core of reserve in which people can extract resources sustainably –Habitat corridor Strip of protected land connecting two reserves that allows animals to migrate from one area to another.

© Cengage Learning 2015 Megareserves – large conservation areas –Designed to sustain about 80% of the country’s biodiversity Large eco-tourism industry Case Study: Identifying and Protecting Biodiversity in Costa Rica

Fig , p. 236

© Cengage Learning 2015 Fig , p. 236

© Cengage Learning 2015 Wilderness –Land officially designated as having no serious disturbance from human activities –Wilderness Act of % of U.S. land protected as wilderness Wilderness protection is being eroded because fewer people are taking part in outdoor activities. Protecting Wilderness Is an Important Way to Preserve Biodiversity

© Cengage Learning 2015 Fig , p. 237

© Cengage Learning 2015 We can help to sustain terrestrial biodiversity by: –Identifying and protecting severely threatened areas (biodiversity hotspots), sustaining ecosystem services –Restoring damaged ecosystems (using restoration ecology) –Sharing with other species much of the land we dominate (using reconciliation ecology) 10-5 What is the Ecosystem Approach to Sustaining Terrestrial Biodiversity?

© Cengage Learning Map global ecosystems and identify species 2. Identify resilient and fragile ecosystems 3. Protect the most endangered 4. Restore as many degraded ecosystems as possible 5. Make development biodiversity friendly The Ecosystems Approach: A Five-Point Strategy

© Cengage Learning biodiversity hot spots are rich in plant species and in great danger of extinction. –2% of earth’s surface, but 50% of flowering plant species and 42% of terrestrial vertebrates –Home to 1/5 of the world’s population (1.2 billion people) Protecting Global Biodiversity Hot Spots Is an Urgent Priority

© Cengage Learning 2015 Fig , p. 238

© Cengage Learning 2015 The world’s fourth largest island Roughly 90% of the species found there are unique Severe habitat loss Population growth Less than 3% of the land area is officially protected Case Study: Madagascar: An Endangered Center of Biodiversity

© Cengage Learning 2015 Fig , p. 239

© Cengage Learning U.N. Millennium Ecosystem Assessment –Identified key ecosystem services –Discovered that human activities degrade or overuse 60% of the earth’s natural services Identify highly stressed life raft ecosystems –Residents, public officials, and conservation scientists would work together to protect human communities and biodiversity. Protecting Ecosystem Services Is Also an Urgent Priority

© Cengage Learning 2015 Ecological restoration –Process of repairing damage from humans –Succession processes: Restoration (returning to natural state) Rehabilitation (turning into functional ecosystem without restoring to original state) Replacement (replacing with a new ecosystem) Creating artificial ecosystems (ex: artificial wetland) We Can Rehabilitate and Partially Restore Ecosystems That We Have Damaged

© Cengage Learning 2015 Steps for carrying out restoration or rehabilitation –1. Identify what caused the degradation –2. Stop the abuse –3. Reintroduce species, if possible –4. Protect from further degradation We Can Rehabilitate and Partially Restore Ecosystems (cont’d.)

© Cengage Learning 2015 Reconciliation ecology –Invent and maintain habitats for species diversity where people live, work, and play –For example: ecotourism Community-based conservation –Protect vital insect pollinators We Can Share Areas We Dominate With Other Species

What Can You Do? Sustaining Terrestrial Biodiversity Fig , p. 242

© Cengage Learning 2015 The economic values of the important ecological services provided by the world’s ecosystems are far greater than the value of the raw materials obtained from those systems Three Big Ideas

© Cengage Learning 2015 We can manage forests, grasslands, and nature reserves more effectively by: –Protecting more land –Preventing overuse and degradation of these areas and the renewable resources they contain Three Big Ideas (cont’d.)

© Cengage Learning 2015 We can sustain terrestrial biodiversity and ecosystem services by: –Protecting biodiversity hotspots and ecosystem services –Restoring damaged ecosystems –Sharing with other species much of the land we dominate Three Big Ideas (cont’d.)

© Cengage Learning 2015 Costa Rica protects a larger portion of its land than any other country Principles of biodiversity –Respect biodiversity and understand the value of sustaining it –Place an economic value on ecosystem services –Encourage people to work together Tying It All Together: Sustaining Costa Rica’s Biodiversity

© Cengage Learning 2015 Forest for People: online/play/7605/Forests-For-Peoplehttp:// online/play/7605/Forests-For-People Forests under fire: cdbu5Q