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Land and Water Use Topics Rangeland Urban Land Development Public and Federal Lands Mining Fishing Global Economics Rangeland Rangeland Vast natural landscapes with different vegetation including tall and short grasslands, chaparral, scrubland, woodlands, and wetlands Covered in natural vegetation and often used as grazing lands Rangelands Rangelands are about 40% of the land in the US Nearly 80% of the land in the west Only 7% on the east coast Value of Rangelands Source of grazing for livestock and wildlife Low input, fully renewable food production Source of high quality water, clean air, and open space Setting for recreation Fishing, hunting, camping, hiking, nature experiences Used for agriculture, mining, and living communities Habitat for many game and non-game animals Habitat for diverse array of natural plants Overgrazing Occurs when plants are exposed for too long without sufficient recovery periods. Plants that are overgrazed lose their stored energy and die Root dieback can add nutrients to the soil and improve water retention Plants are over grazed when it is regrazed before the roots recover Overgrazing slows root growth by 90% Consequence of overgrazing Pastures are less productive Soils have less organic matter and are less fertile Soil porosity is decreased Infiltration and moisture holding capacity of the soil drops Desired plants become stressed and weedier species thrive Biodiversity decreases by reducing native vegetation Consequence of overgrazing Erosion can occur Riparian (river banks, stream beds) can be destroyed and increase silting Eutrophication due to cattle waste Balance of ecosystem is threatened through predator control programs Diseases can thrive Sustainability of the land is threatened Desertification Conversion of marginal rangeland or cropland to more desert type land Caused by: Overgrazing Soil erosion Prolonged drought Climate change Steps of desertification 1. 2. 3. 4. 5. 6. 7. Overgrazing results in animals eating all available plant life Rain washes away trampled soil Wells, springs, and other water sources dry up Remaining vegetation dies or is taken for firewood Weeds unsuitable to grazing take over Ground becomes unsuitable for seed germination Winds and dry heat blow away the topsoil Federal Rangeland Management Jurisdiction through Forest Service and Bureau of Land Management (BLM) Before 1995: policies determined by rancher advisory boards After 1995: resource advisory council was formed by member of many groups with many interests 40% of federal grazing permits are owned by 3% (~2000) of all livestock operators True cost =~$10 - $20 per animal per day Methods of rangeland management 1. 2. 3. 4. 5. Controlling the number and distribution of livestock so that the carrying capacity is not exceeded Restoring degraded rangeland Moving livestock from one area to another to allow the rangeland to recover Fencing off riparian areas to reduce damage to these sensitive areas Suppressing the growth of invasive plant species Methods of rangeland management 6. 7. 8. Replanting barren rangeland with native grass seed to reduce soil erosion Providing supplemental feed at selected sites Locating water holes, water tanks, and salt blocks at strategic points that do not degrade the environment Conservation concerns Land administered by the BLM is inhabited by 219 species of wildlife Livestock grazing is the fifth rated threat to endangered plant species, fourth leading threat to endangered wildlife, and number one threat to endangered species in arid regions Urban Land Development Planned Development In US Use: 76 million residential buildings 5 million commercial buildings 1/3 of the energy 2/3 of the electricity Energy needs ½ of sulfur dioxide 1/4 of nitrous oxide 1/3 of carbon dioxide Green buildings and cities Focus on systems approach Include: Energy conservation through government and private rebates, tax incentives, and other lesspolluting forms of energy Resource-efficient building techniques and materials Indoor air quality Water conservation through use of xeriscaping Designs that minimize waste while utilizing recycled materials Green buildings and cities Include: Placing buildings whenever possible near public transportation hubs that use a multitude of venues such as light rail, subways, and park and rides Creating environments that are pedestrian friendly by incorporating parks, green-belts, and shopping areas in accessible areas Preserving historical and cultural aspects of the community while at the same time blending into natural feeling and aesthetics of a community Suburban sprawl and urbanization Urbanization = the movement of people form rural areas to cities and the changes that accompany it Greatest urbanization in Asia and Africa Reasons for the move: Access to jobs Easier access to health care Mechanization of agriculture Access to education Nations with most rapid increase in urbanization are those with the most rapid economic growth Pros of urbanization Uses less land – less impact on the environment Better education delivery system Mass transit systems reduce reliance on fossil fuels – shorter commute Better sanitation Recycling systems are more efficient Large numbers of people generate higher tax revenues Urban areas attract industry due to availability of raw materials, distribution networks, customers, and labor pool Much pollution comes from point sources – enables focused remediation techniques Cons of urbanization More concentrated impact on the land Overcrowded schools Commuting times are longer because infrastructure cannot keep up with growth Sanitiation systems have greater volumes of waste to deal with Solid-waste build up is more pronounced – landfill space is scarce and costly Large number of poor strain social services – wealthier people move to suburbs and decreases the tax base High population densities lead to higher crime rates Population increase may be greater than job growth rate Pollution levels are high Transportation and Infrastructure Transportation can be via roadways or water channels Areas without transportation infrastructure suffer ecosystem impacts Degraded environment due to off-roading People take multiple paths through the environment instead of just one Federal Highway System ~160,000 miles of roadway important to nations economy, defense, and mobility Receive federal funding but are owned, built, and operated by the states Taxes 18 cents/ gallon of gas 25 cents/ gallon of diesel Tax on heavy vehicles Federal Highway System Continued Serves all major US cities Interstates go through downtown areas and facilitate urban sprawl Virtually all goods and services go involve the highways system at some point in time Impact of an efficient and well maintained highways system Less pollution: less stop and go traffic = less pollution Reduced green house gasses: reduced congestion = less greenhouse gas emissions Improve fuel economy and reduce dependence on foreign oil: fueled economy (mpg) is reduced in traffic Modest improvements would save 1 billion gallons of fuel each year Improve the economy: interstates return $6 for every $1 invested Improve the quality of life: allow products to be distributed more efficiently Canals and Channels Channel (straight) – narrow body of water that connect two larger bodies of water Can be natural or constructed Need dredging because of silting Channels Channels frequented by ships are maintained by the Department of the Interior Monitored and policed by the Coast Guard Smaller channels are maintained by state and local governments Suez Canal 163 mile canal connect the Red Sea and the Mediterranean Allows water transport between Europe and Asia without going around Africa 8% of the world’s shipping goes through the Suez Canal Panama Canal 48 mile canal connecting the Pacific Ocean with the Atlantic Allows water transport without going around South America Lake Gatun An artificial lake created to help traffic on the Panama Canal Deforestation has lead to rapid run off of rain and erosion of the slopes The lake needs to be dredged to maintain its depth Shortfall in the dry season threatens the lake’s capacity Roadless Areas and Ecosystem Impact Roadless areas are a haven for fish and wildlife interior species that have suffered habitat loss in other areas Provide habitat to 1600+ threatened or endangered species Protects watersheds Roadless rule protects 60 million acres or 31% of National Forest systems – 2% of total land area Public and Federal Lands Management – BLM Manages: 1/8 of the United States (262 million acres) 300 million acres of subsurface mining resources Wildlife management and preservation on 400 million acres Mostly in western US and Alaska Grasslands, forests, high mountains, arctic tundra, deserts Resources: energy, mineral, timber, forage, wild horse and burro populations, fish and wildlife habitats, wilderness, areas, archeological, paleontological, and historical sites National Parks World wide: over 1,100 Most do not receive protection from poachers, loggers, miners, and farmers due to cost involved U.S. National Parks 84 million acres (4 million in private ownership) Threatened by: large numbers of visitors Congestion eroded trails noise pollution pollution from autos and visitors introduction of invasive species off road vehicles commercial activities Solution to national park issues Reducing amount of private land within national parks Providing education programs to the public Setting quotas on attendance through advanced reservation Adopting a fee that covers costs Banning off-road vehicles Banning autos and providing buses to control traffic Providing tax incentives to property owners near parks to use land grants Conducting periodic and detailed wildlife and plant inventories Laws relevant to national parks Wilderness act (1964) Wild and scenic rivers act (1968) Food Security Act (1985): a.k.a “Swampbuster” contains provisions to discourage the conversion of wetlands into non-wetland areas. Also created system for farmers to regain lost federal benefits if they restore converted wetlands. Wildlife Refuges 1st: Pelican Island, 4-acres off the coast of Florida in 1903 to protect breeding birds First created to protect wildlife that was over hunted Bison, birds System developed piecemeal in response to wildlife crisis National Wildlife Refuge Consists of: 547 refuges 93+ million acres Managed by Fish and Wildlife Service Wetlands Areas that are covered by water and support plants that can grow in water-saturated soil High plant productivity Support rich diversity of animal life Countries with most: Canada Russian Federation Brazil Value of wetlands Natural water purification systems Stabilize shorelines and reduce damage by storm surges Reduce the risk of flooding Reduce salt water intrusion Habitat for many species during all or part of their life cycle Types of Wetlands Fen Has a continuous source of ground water rich in magnesium and calcium (alkaline or basic) Water is from glacial deposits Ground is impermeable to water so water sits on the surface Bog Accumulates acidic peat In cold and temperate climates Low in nutrients and highly acidic Carnivorous plants adapted Habitat Loss In US, wetlands used to cover 10% of the land; now they only cover 5% Most in Louisiana and Florida 90% of habitat loss is due to conversion to agriculture or urban development 1/3 of all endangered species in US spend part of their life in a wetland Wilderness areas Wild or primitive portions of national forests, parks, and wildlife refuges where little to no human activity occurs Wilderness Act created National Wilderness Preservation System Encompasses a wide variety of ecosystems throughout the country