Land How We Use Land Land use and

Land

How We Use Land • Land use and cover – What you find on a patch of land • Farm, forest, city, wetlands, homes, etc… – Urban • Buildings and roads • > 2, 500 people – Rural • Open space • Few people

Primary Land Uses • Land cover types – Rangeland – Forest land – Cropland – Parks/Preserves – Wetlands, mountains, deserts, other – Urban land

Where We Live • Until ~1850 – rural areas – Industrial revolution • Better machinery less people needed on farms moved to cities for jobs – Transportation improved » Goods could be moved more easily – Almost half of world’s population live in cities » >1/2 will by 2007 » Most rapid in developing countries

United States

Urban-Rural Connection • Dependence upon rural resources – Ecosystem services • Clean air and water • Soil • Flood/drought prevention • Regulation of climate • Biodiversity • Cycling of nutrients • Detoxification • Aesthetic beauty

Example - Resources From Forests

Urban Land Use • The urban crisis – Rapid growth stresses infrastructure • All public societal needs – Living conditions deteriorate

Urban Land Use • Urban sprawl – Rapid expansion onto countryside • Suburbs – Typically farms homes » 2. 5 million acres per year – More Americans live in suburbs than cities and countryside combined

Development on Marginal Lands • Many cities established in areas with limited space – Suburbs end up in marginal areas • Poorly suited for building

Other Impacts • Heat islands – Cities generate and trap more heat than the countryside • Atlanta, GA – City ~10 o. F warmer – Changes local weather more rain

Atlanta, GA

Urban Planning • Land-use planning – Plan before building • Can be used to plan for minimal impact • Developers must develop plans – Public information – Use GIS • Geographic information systems – Use satellites to photograph Earth

• Open space Urban Planning – Land set aside for scenic and recreational enjoyment • Left natural – Absorb CO 2 and produce O 2 – Filter pollutants – Absorb water

Management and Conservation • Farmland – >250 million acres in the US – Farmland Protection Program • Helps buy land to prevent it from being developed

Management and Conservation • Rangelands – Land that supports vegetation but not used for agriculture • Often used to feed livestock – Overgrazing invasive plants or erosion » Much is in need of repair

Management and Conservation • Forest lands – Trees harvested for many uses – Wood use • 1, 800 cm 3/person/day • Person in US – 100 ft tree/year – Clear-cutting • Cutting down all trees in an area – Selective cutting • Removing only middle-aged and mature trees

Management and Conservation – Deforestation • Clearing trees without replanting more – To make farms, homes, roads, factories – Leads to soil erosion – Reforestation • Planting replacement trees – Mandatory in some areas when trees are cut down

Management and Conservation • Parks and preserves – Yellowstone = 1 st National Park • ~50 today – Public lands serve many purposes • May be leased to private companies – Wilderness • Protected from all exploitation – 32 million acres in US – Millions of visitors serious impact