Case Study: Remember Wolves In Yellowstone  Endangered Species – two million wolves were destroyed  Keystone Species –Keeps herbivore population in check (elk, moose) –Vegetation reestablishes –Species diversity expands (beavers & ducks return) Figure 10-1

HUMAN IMPACTS ON TERRESTRIAL BIODIVERSITY Habitat Loss – deforestation Habitat Fragmentation – roads, highways, buildings Invasive Species Pollution Figure 10-2

Ecosystem Services of Forests Figure 10-4

Types of “Protected” Lands in U.S.  Multiple-use lands  National Forest (U.S.F.S.)  sustainable yield  multiple use  used for logging, mining, grazing, farming, oil, recreation, hunting and conservation  National Resource lands (BLM)  mostly out west and Alaska  multiple use  used for mineral and oil extraction/ grazing

Types of “Protected” Lands  Moderately Restricted-Use Lands  National Wildlife Refuges (USFWS)  522 refuges  24% designated as wilderness  protect habitats  oil, farming, hunting, mineral extraction are allowed as long as Dept. of Interior says OK

Types of Protected Lands  Restricted-Use lands  National Park System (NPS)  55 National Parks and 324 recreation areas, battlefields, memorials, etc.  Preserve and interpret the country’s historic and cultural heritage and protect wilderness areas  Parks can be used for camping, hiking, fishing and boating  Rec areas: also mining and oil  49% of National Park system is wilderness

Locations of Parks, Preserves, Forests and Refuges

Types of Forests Old-growth forest : uncut or regenerated forest that has not been seriously disturbed for several hundred years –22% of world’s forest –Hosts many species with specialized niches Figure 10-5 Due to human activities over 50% of the earth’s original forests have been removed.

Types of Forests Second-growth forest : a stand of trees resulting from natural secondary succession Tree plantation: planted stands of a particular tree species Figure 10-6

Impact of Deforestation Figure 10-7

Case Study: Deforestation and the Fuelwood Crisis Almost half the people in the developing world face a shortage of fuelwood and charcoalAlmost half the people in the developing world face a shortage of fuelwood and charcoal –In Haiti, 98% of country is deforested –MIT scientist has found a way to make charcoal from spent sugarcane

Harvesting Trees Figure 10-8  Increased erosion and runoff  Habitat fragmentation  Pathways for exotic species  Accessibility to humans

Harvesting Trees Trees can be harvested individually from diverse forests (selective cutting)Trees can be harvested individually from diverse forests (selective cutting) an entire forest can be cut down (clear cutting)an entire forest can be cut down (clear cutting) portions of the forest is harvested (strip cutting)portions of the forest is harvested (strip cutting) Figure 10-9

Harvesting Trees Effects of clear-cutting in the state of Washington, U.S. Figures and 10-11

Solutions We can use forests more sustainably by emphasizing:We can use forests more sustainably by emphasizing: –Economic value of ecological services. –Harvesting trees no faster than they are replenished. –Protecting old-growth and vulnerable areas. Figure 10-12

CASE STUDY: FOREST RESOURCES AND MANAGEMENT IN THE U.S. U.S. forests cover more area than in 1920.U.S. forests cover more area than in Since the 1960’s, an increasing area of old growth and diverse second-growth forests have been clear-cut.Since the 1960’s, an increasing area of old growth and diverse second-growth forests have been clear-cut. –Often replace with tree farms. –Decreases biodiversity. –Disrupts ecosystem processes.

Types and Effects of Forest Fires Depending on their intensity, fires can benefit or harm forestsDepending on their intensity, fires can benefit or harm forests –Burn away flammable ground material –Release valuable mineral nutrients Figure 10-13

Fire  Surface fires  Crown fires Surface fire Crown fire

Solutions: Controversy Over Fire Management To reduce fire damage:To reduce fire damage: –Set controlled surface fires –Allow fires to burn on public lands if they don’t threaten life and property –Clear small areas around property subject to fire

Solutions: Controversy Over Fire Management In 2003, U.S. Congress passed the Healthy Forest Restoration Act:In 2003, U.S. Congress passed the Healthy Forest Restoration Act: –Allows timber companies to cut medium and large trees in 71% of the national forests. –In return, must clear away smaller, more fire-prone trees and underbrush. –Some forest scientists believe this could increase severe fires by removing fire resistant trees and leaving highly flammable slash.

Controversy over Logging in U.S. National Forests There has been an ongoing debate over whether U.S. national forests should be primarily for:There has been an ongoing debate over whether U.S. national forests should be primarily for: –Timber –Ecological services –Recreation –Mix of these uses Figure 10-14

Solutions: Reducing Demand for Harvest Trees Tree harvesting reduced by wasting less wood, making paper and charcoal fuel from fibers that don’t come from treesTree harvesting reduced by wasting less wood, making paper and charcoal fuel from fibers that don’t come from trees –Kenaf is promising plant for paper production Figure 10-15

American Forests in a Globalized Economy Timber from tree plantations in temperate and tropical countries is decreasing the need for timber production in the U.S.Timber from tree plantations in temperate and tropical countries is decreasing the need for timber production in the U.S. –This could help preserve the biodiversity in the U.S. by decreasing pressure to clear-cut old-growth and second-growth forests –This may lead to private land owners to sell less profitable land to developers –Forest management policy will play a key role

CASE STUDY: TROPICAL DEFORESTATION Large areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rateLarge areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rate Figure 10-16

CASE STUDY: TROPICAL DEFORESTATION At least half of the world’s terrestrial plant and animal species live in tropical rain forestsAt 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 cropsLarge areas of tropical forest are burned to make way for cattle ranches and crops Figure 10-17

Why Should We Care about the Loss of Tropical Forests? About 2,100 of the 3,000 plants identified by the National Cancer Institute as sources of cancer- fighting chemicals come from tropical forests.About 2,100 of the 3,000 plants identified by the National Cancer Institute as sources of cancer- fighting chemicals come from tropical forests. Figure 10-18

Causes of Tropical Deforestation and Degradation Tropical deforestation results from a number of interconnected primary and secondary causes.Tropical deforestation results from a number of interconnected primary and secondary causes. Figure 10-19

Kenya’s Green Belt Movement: Individuals Matter Wangari Maathai founded the Green Belt MovementWangari Maathai founded the Green Belt Movement The main goal is to organize poor women to plant (for fuelwood) and protect millions of treesThe main goal is to organize poor women to plant (for fuelwood) and protect millions of trees In 2004, awarded Nobel peace prizeIn 2004, awarded Nobel peace prize Figure 10-10A

MANAGING AND SUSTAINING GRASSLANDS Almost half of the world’s livestock graze on natural grasslands (rangelands) and managed grasslands (pastures)Almost half of the world’s livestock graze on natural grasslands (rangelands) and managed grasslands (pastures) We can sustain rangeland productivity by controlling the number and distribution of livestock and by restoring degraded rangelandWe can sustain rangeland productivity by controlling the number and distribution of livestock and by restoring degraded rangeland

MANAGING AND SUSTAINING GRASSLANDS Overgrazing (left) occurs when too many animals graze for too long and exceed carrying capacity of a grassland area.Overgrazing (left) occurs when too many animals graze for too long and exceed carrying capacity of a grassland area. Figure 10-21

MANAGING AND SUSTAINING GRASSLANDS Example of restored area along the San Pedro River in Arizona after 10 years of banning grazing and off-road vehicles.Example of restored area along the San Pedro River in Arizona after 10 years of banning grazing and off-road vehicles. Figure 10-22

Case Study: Grazing and Urban Development in the American West Ranchers, ecologists, and environmentalists joining together to preserve grasslands on cattle ranchesRanchers, ecologists, and environmentalists joining together to preserve grasslands on cattle ranches –Paying ranchers conservation easements (barring future owners from development) –Pressuring government to zone land to prevent development of ecologically sensitive areas

NATIONAL PARKS Countries established more than 1,100 national parks, but most threatened by human activitiesCountries established more than 1,100 national parks, but most threatened by human activities –Local people invade park for wood, cropland, & other natural resources –Loggers, miners, & wildlife poachers also deplete natural resources –Many are too small to sustain large-animal species –Many suffer from invasive species

Case Study: Stresses on U.S. National Parks Overused due to popularityOverused due to popularity Inholdings (private ownership) within parks threaten natural resourcesInholdings (private ownership) within parks threaten natural resources Air pollutionAir pollution Figure 10-23

Suggestions for sustaining and expanding the national park system in the U.S.Suggestions for sustaining and expanding the national park system in the U.S. Figure 10-24

NATURE RESERVES Ecologists call for protecting more land to help sustain biodiversity, but powerful economic and political interests oppose doing this.Ecologists call for protecting more land to help sustain biodiversity, but powerful economic and political interests oppose doing this. –Currently 12% of earth’s land is protected –Only 5% strictly protected from harmful human activities –Conservation biologists call for full protection of at least 20% of earth’s land area representing multiple examples of all biomes

How Would You Vote? To conduct an instant in-class survey using a classroom response system, access “JoinIn Clicker Content” from the PowerLecture main menu for Living in the Environment. Should at least 20% of the Earth's land area be strictly protected from economic development?Should at least 20% of the Earth's land area be strictly protected from economic development? –a. No. Such protections would encourage people to poach and illegally extract resources from the expanded reserves. –b. Yes. The project is desperately needed to protect the Earth's biodiversity.

NATURE RESERVES Large and medium-sized reserves with buffer zones help protect biodiversity and can be connected by corridors.Large and medium-sized reserves with buffer zones help protect biodiversity and can be connected by corridors. Costa Rica has consolidated its parks and reserves into 8 megareserves designed to sustain 80% if its biodiversity.Costa Rica has consolidated its parks and reserves into 8 megareserves designed to sustain 80% if its biodiversity. Figure 10-10B

NATURE RESERVES A model biosphere reserve that contains a protected inner core surrounded by two buffer zones that people can use for multiple use.A model biosphere reserve that contains a protected inner core surrounded by two buffer zones that people can use for multiple use. Figure 10-25

NATURE RESERVES Geographic Information System (GIS) mapping can be used to understand and manage ecosystems.Geographic Information System (GIS) mapping can be used to understand and manage ecosystems. –Identify areas to establish and connect nature reserves in large ecoregions to prevent fragmentation. –Developers can use GIS to design housing developments with the least environmental impact.

NATURE RESERVES We can prevent or slow down losses of biodiversity by concentrating efforts on protecting global hot spots where significant biodiversity is under immediate threat.We can prevent or slow down losses of biodiversity by concentrating efforts on protecting global hot spots where significant biodiversity is under immediate threat. Conservation biologists are helping people in communities find ways to sustain local biodiversity while providing local economic income.Conservation biologists are helping people in communities find ways to sustain local biodiversity while providing local economic income.

34 hotspots identified by ecologists as important and endangered centers of biodiversity.34 hotspots identified by ecologists as important and endangered centers of biodiversity. Figure 10-26

NATURE RESERVES Wilderness is land legally set aside in a large enough area to prevent or minimize harm from human activities.Wilderness is land legally set aside in a large enough area to prevent or minimize harm from human activities. Only a small percentage of the land area of the United States has been protected as wilderness.Only a small percentage of the land area of the United States has been protected as wilderness.

ECOLOGICAL RESTORATION Restoration: trying to return to a condition as similar as possible to original state.Restoration: trying to return to a condition as similar as possible to original state. Rehabilitation: attempting to turn a degraded ecosystem back to being functional.Rehabilitation: attempting to turn a degraded ecosystem back to being functional. Replacement: replacing a degraded ecosystem with another type of ecosystem.Replacement: replacing a degraded ecosystem with another type of ecosystem. Creating artificial ecosystems: such as artificial wetlands for flood reduction and sewage treatment.Creating artificial ecosystems: such as artificial wetlands for flood reduction and sewage treatment.

ECOLOGICAL RESTORATION Five basic science-based principles for ecological restoration:Five basic science-based principles for ecological restoration: –Identify cause. –Stop abuse by eliminating or sharply reducing factors. –Reintroduce species if necessary. –Protect area form further degradation. –Use adaptive management to monitor efforts, assess successes, and modify strategies.