Land Resources. Overview Land Use – World land use – US land use Wilderness Park and Wildlife Refuges – National Parks – Wildlife Refuge Forests – Forest.

Land Resources

Overview • Land Use

– 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

Land Use- Worldwide

Land Use- United States

Military lands and research facilities not included

Land Use- United States• 55% of US land is privately owned by citizens corporations

and non-profit organizations• 3% owned by Indians (Native Americans)• Remainder of land is owned by government– Most federally owned land is in Alaska and 11 western

states

Managing Public and Private Land

• Public Planning and Land Use– Must take into account all repercussions of

proposed land use (must avoid Trajedy of the Commons)

• Management of Federal Land– Wide-Use Movement– Environmental Movement

Wilderness Parks and Wildlife Refuges

• Wilderness– 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 (White Pine blister rust in Rockies)

Selway-Bitterroot Wilderness in Idaho

National Park System

• Created in 1916 (first National Park; Yellowstone was established in 1872)

• Currently includes 58 parks

• Primary goal– Teach people about the

natural environment, management of natural resources and history of a site

Yosemite National ParkYosemite National Park

Merced River flowing past El Capitan

National Park System

• Threats to U.S. Parks– 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 found 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)

• Most of water that falls as precipitation is released back into the atmosphere through transpiration

• Widescale loss alters climates

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

Intensively managed Pine Plantation is a monoculture; US currently consumes 20% more Timber than it replaces

Harvesting Trees

Harvesting Trees - Clearcutting

Clear cutting must STOP!!!

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

Deforestation

• Results– Decreased soil fertility– Uncontrolled soil erosion– Production of hydroelectric power (silt build up

behind dams)– Increased sedimentation of waterways– Formation of deserts– Extinction of species– Global climate changes

Forest Trends in US

• Most temperate 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- helps

protect environmentally important forest lands

– Conservation easement – protects the forest property for development for a given number of years

US National Forests (155 Ntl. Forests ;191 million Acres according to USFS)

• Managed for multiple uses– Timber harvest– Livestock forage– Water resource and watershed protection– Mining, hunting, fishing, etc.

• Road building is an issue– Taxpayer funded roads allow logging companies

with access to forest (money is not reimbursed) • Clearcutting is an issue

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 and tropical dry forests (what remains is highly fragmented)

Disappearing Tropical Rain Forests

• Population growth– Cannot account for all of

it• Immediate causes– Subsistence agriculture

(60% of deforestation)– Commercial logging (20%)– Cattle ranching (12%)

• Other causes– Mining– Hydroelectric power

As more and more farmers settle along the roads they clear out more of the forests

Disappearing Tropical Dry Forests

• Primarily destroyed for fuelwood– Used for heating and cooking

Gathering firewood in Ranthambore National Park buffer zone. Note how the branches have been trimmed off the trees in the background

Boreal Forests (Taiga)• World’s largest biome• Extensive clearcutting

– Primary source of world’s industrial wood and wood fiber– Annual loss is equivalent to twice the size of the Amazonian rainforests of Brazil– Canada is the worlds largest timber exporter

Rangeland and Agricultural lands

• Rangeland– Land that is not intensively managed and is used for grazing livestock– Grasses have a fibrous root system and benefit from animals grazing

as long as the carrying capacity has not been met

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) (allow fewer livestock

permitted to graze rangelands)– Federal Land Policy and Management Act (1976)

• Conditions of public rangeland are slowly improving (fewer livestock allowed to graze)– Grazing fees is an issue (cheaper on public land and taxpayers

contributing more money than the grazers

Agricultural Land

• US has 300 million acres of prime farmland

o Much is being Much is being overtaken by overtaken by suburban suburban sprawlsprawl• Parking lotsParking lots• Housing Housing

developmentsdevelopments• Shopping mallsShopping malls Homes and businesses occupying what was once cornfields In York City

Pennsylvania.According to the American Farmland Trust 400,000 acres of prime US farmland are lost each year

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: (conserving new and restoring old)

• Development of wetlands is allowed if corresponding amount of previously converted wetland is restored

• Not all wetland restorations are successful

A Reconstructed Wetland (failure)•Sweetwater Marsh constructed in 1984 along San Diego Bay• California Department Of Transportation was legally required to do so because it destroyed a similar marsh for road construction•Intended top provide habitat for the light-footed clapper rail •Never worked out because the marsh grass was not high enough to provide ample nesting sites• Natural marshes have sediments that retain the nitrogen in the sediments necessary to grow the taller grasses• reconstructed sediments were too sandy to retain the nutrients

Coastlines

• Coastal wetlands– Provide food and habitat for many aquatic animals– Historically regarded as wasteland (only good for

mosquitos)

o US starting to see US starting to see importance of protecting importance of protecting this environment this environment (NURSERIES FOR FISH)(NURSERIES FOR FISH)

• Retaining seawalls (right) Retaining seawalls (right) eventhough the sea wall helps eventhough the sea wall helps protect the home the cause much protect the home the cause much faster rates of erosion further faster rates of erosion further down the beach where there are down the beach where there are no seawallsno seawalls

Coastal Demographics• Many coastal areas overdeveloped

– 3.8 billion people live within 150km of coastline– 6.4 billion people will likely live there by 2025

o United StatesUnited States• 14 of 20 largest US cities along coast14 of 20 largest US cities along coast• 19 of 20 most densely populated countries along 19 of 20 most densely populated countries along

coastscoasts

Conservation and Land Resources• All types of ecosystems must be preserved• Four criteria of importance used as a ranking

system:– 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

MATH PRACTICE

• Excluding agriculture, only about 0.8% of the Earth's total surface area (which is 14.7 billion hectares) is settled (homes, roads, cities, etc.). What is this settled area in hectares?

• a) 8 billion hectares• b) 8 million hectares• c) 117.6 million hectares• d) 1.176 billion hectares• e) 11.76 billion hectares

Answer

• Ans: c• Response: • .008 * 14.7 billion hectares = .1176 billion

hectares = 117.6 million hectares