Chapter 18 Land Resources

Overview of Chapter 18 Land Use Wilderness Park and Wildlife Refuges World land use US land use Wilderness Park and Wildlife Refuges National Parks Wildlife Refuge Forests Forest management Deforestation Rangeland and Agricultural Land Wetlands and Coastal Areas Conservation of Land Resources

HUMAN IMPACTS ON TERRESTRIAL BIODIVERSITY We have depleted and degraded some of the earth’s biodiversity and these threats are expected to increase. Figure 10-2

Land Use- Worldwide

Land Use- United States

Forest Trends in US Most temperature forest are steady or expanding Returning stands lack biodiversity of original forests More than half of US forest are privately owned (right) Forest Legacy Program Conservation easement

Managing Public and Private Land Public Planning and Land Use Land use decisions are complex and have multiple effects Must take into account all repercussions of proposed land use Management of Federal Land Wide-Use Movement Environmental Movement

Wilderness Parks and Wildlife Refuges A protected area of land in which no human development is permitted Wilderness Act (1964) Set aside federally owned land as part of National Wilderness Preservation System No development permitted (including roads) Managed by NPS, USFS, FWS & BLM

Wilderness Some areas have a limited number of permitted human guests to reduce impact Other problems include invasive species

National Park System Created in 1916 Currently includes 58 parks Yosemite National Park Created in 1916 Currently includes 58 parks Primary goal Teach people about the natural environment, management of natural resources and history of a site

National Park System Threats to U.S. Parks Natural Regulation Crime & Vandalism Traffic jams Pollution of the soil, water and air Originating both inside and outside the park Resource violations Natural Regulation Policy to let nature take it course No culling wildlife No suppressing wildfire

Wildlife Refuges National Wildlife Refuge System (1903) Represent all major ecosystems founds in the US Mission To preserve lands and waters for the conservation of fishes, wildlife and plants of the US Recreation (including hunting and fishing) are permitted Cannot impede conservation efforts

Forests Role in Hydrologic Cycle (right) Forest Management Deforestation Forest Trends in the US Trends in Tropical Forests Boreal Forests

MANAGING AND SUSTAINING FORESTS Forests provide a number of ecological and economic services that researchers have attempted to estimate their total monetary value. Figure 10-4

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

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

Forest Management Traditional Forest Management Low diversity- monocultures (right) Managed for timber production Ecological Sustainable Forest Management Environmentally balanced Diverse trees Prevent soil erosion Preserve watersheds Wildlife corridors- unlogged

Harvesting Trees Building roads into previously inaccessible forests paves the way for fragmentation, destruction, and degradation. Figure 10-8

Harvesting Trees

Harvesting Trees - Clearcutting

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

Deforestation Temporary or permanent clearance of large expanses of forest for agriculture or other use World forests shrank 90 million acres from 2000–2005 Causes Fire Expansion of agriculture Construction of roads Tree harvest Insect and disease

Global Outlook: Extent of Deforestation Human activities have reduced the earth’s forest cover by as much as half. Losses are concentrated in developing countries. Figure 10-7

Solutions 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

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

Solutions: Controversy Over Fire Management 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: 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.

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. Do you support repealing or modifying the Healthy Forests Restoration Act of 2003? a. Yes. Local officials and scientists are probably most qualified to manage their local forests. b. No. The initiative favors the timber companies rather than effectively protecting and managing the forests.

US National Forests Managed for multiple uses Timber harvest Livestock forage Water resource and watershed protection Mining, hunting, fishing, etc. Road building is an issue Provides logging companies with access to forest Clearcutting is an issue

CASE STUDY: FOREST RESOURCES AND MANAGEMENT IN THE U.S. U.S. forests cover more area than in 1920. 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.

Controversy over Logging in U.S. National Forests 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

Case-In-Point Tongass National Park One of world’s few temperate rainforests Prime logging area Modified 1997 Forest Plan Roadless Area Conservation Rule (2000) Politics rules government agencies

Trends in Tropical Forests Tropical rainforests (below) and tropical dry forests

Disappearing Tropical Rain Forests Population growth Cannot account for all of it Immediate causes Subsistence agriculture Commercial logging Cattle ranching Other causes Mining Hydroelectric power

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. Figure 10-18

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

Sustaining Tropical Forests Solutions Sustaining Tropical Forests Prevention Restoration 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 and conservation easements 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 Figure 10.20 Solutions: ways to protect tropical forests and use them more sustainably. QUESTION: Which three of these solutions do you think are the most important? Fig. 10-20, p. 207

Disappearing Tropical Dry Forests Primarily destroyed for fuelwood Used for heating and cooking

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

Boreal Forests World’s largest biome Extensive clearcutting Primary source of world’s industrial wood and wood fiber

Rangeland and Agricultural lands Land that is not intensively managed and is used for grazing livestock

Rangeland Degradation and Deforestation Overgrazing leaves ground barren Animals exceed their carrying capacity Land degradation Natural or human-induced process that decreases future ability of land to support crops or livestock Desertification Degradation of once fertile land into nonproductive desert

Rangeland Trends in US Make up 30% of total US land area 2/3 privately owned Pressure from developers to subdivide Public rangeland managed by: Taylor Grazing Act (1934) Federal Land Policy and Management Act (1976) Conditions of public rangeland are slowly improving Grazing fees is an issue

Agricultural Land US has 300 million acres of prime farmland Much is being overtaken by suburban sprawl Parking lots Housing developments Shopping malls

Wetlands Lands that are usually covered with water for at least part of the year Have characteristic soils and water-tolerant vegetation Benefits Habitat for migratory waterfowl and wildlife Recharge groundwater Reduce damage from flooding Improve water quality Produce many commercially important products

Wetlands Human activity that threatens wetlands Drainage for agriculture or mosquito control Dredging for navigation Construction of dams, dykes or seawalls Filling in for solid waste disposal Road building Mining for gravel, fossil fuels, etc. Shrinking 58,500 acres per year

Restoring Wetlands No Net Loss of Wetlands: Development of wetlands is allowed if corresponding amount of previously converted wetland is restored Not all wetland restorations are successful

Coastlines Coastal wetlands Provide food and habitat for many aquatic animals Historically regarded as wasteland US starting to see importance of protecting this environment Retaining seawalls (right)

Coastal Demographics Many coastal areas overdeveloped United States 3.8 billion people live within 150km of coastline 6.4 billion people will likely live there by 2025 United States 14 of 20 largest US cities along coast 19 of 20 most densely populated countries along coasts

Conservation and Land Resources All types of ecosystems must be preserved Four criteria of importance: Areas lost or degraded since European colonization Number of present examples of a particular ecosystem (or the total area) Estimate of the likelihood that a given ecosystem will lost a significant area or be degraded in next 10 years Number of threatened and endangered species living in the ecosystem

Conservation and Land Resources

SOURCE https://sites.google.com/a/siskorea.org/science-bits/ap-environmental-science/apes-assignments/ch-18-20-land-resources