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Land Use

Land Use. DQ: 10/23. Name and Describe three ways that humans use land. How We Use Land. Land Use is measured by: Maps Aerial Photos Field Surveys Computerized mapping system. Land Use.

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Land Use

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  1. Land Use

  2. DQ: 10/23 • Name and Describe three ways that humans use land.

  3. How We Use Land • Land Use is measured by: • Maps • Aerial Photos • Field Surveys • Computerized mapping system

  4. Land Use • Measurements taken in California showed that in 8 years (1984-1992) nearly 210,000 acres of farmland, rangeland and woodland had been converted into suburbs and cities. Issue: • How will we feed the exponential growing population?

  5. Land Us in the United States • 357 million acres of cropland • 406 million acre of forestland • 19 million acres of pastureland • 409 million acres of rangeland

  6. Major Concerns • Major land use natural resource concerns include: • erosion by wind and water • maintaining and enhancing soil quality • water quality and quantity • plant condition and health • wildlife habitat

  7. Land Use and Land Cover • Urban area: • Covered by mainly buildings and roads and defined as an area that contains 2,500 or more people. • Rural area: • Those areas that have relatively less people and more open space.

  8. Agriculture: How to Feed a Growing Population • Clearing land for increased agriculture • Food and Agriculture Organization of the United Nations reported that the number of undernourished people in LDCs increased to over 826 million • 357 million acres of cropland is threatened by urban development. • North Carolina • Twin Cities

  9. Cropland Threatened • In 1996, the U.S. government established the Farmland Protection Program: • Helps protect farmland in danger of being paved over or otherwise developed. • Gives financial assistances to help keep land in agriculture • Since its creation: • 885 million • Purchased 3,993 farms

  10. Types of Agriculture • Conventional, or unsustainable agriculture • Agroecology, or sustainable agriculture • With a partner fill in the table:

  11. Altering Land: Do they change the land? If so, how? (till, irrigate) • Crops/field: How many different crops per field? • Harvest: How often? At the same time? • After Harvest: What happens to the land after harvest? (Bare or not bare)

  12. Conventional agriculture disrupts natural ecology of the field • Land get stripped for planting displacing herbivores without natural vegetation. • Chemical fertilizers, herbicides and pesticides leach into the solid and groundwater • Phosphates stimulate algal blooms in local streams and water sources. • Single crops tend to deplete the soil of vital nutrients. • Bare fields after harvesting are susceptible to soil erosion by wind and rain. • Use of seeds, fertilizer, herbicides and pesticides are expensive.

  13. Green Revolution • Began in the 1940s as a way to help farmers in India and Mexico increase their productivity and relieve hunger. • Developed by a plant scientist: Norman Borlaug • Produced high-yield varieties of wheat that were more resistant to pests and disease. • In the 1960s they developed new high-yield versions of rice, corn and beans • Process called genetic engineering

  14. Green Revolution • Farmers could plant and harvest crops more quickly • Helped relieve famine in Latin America and Asia • However, not successful in all areas because of climate and irrigation techniques not available. • Sub-Saharan Africa

  15. Irrigation • One major factor in the Green Revolution • Uses about 60 percent of the world’s freshwater supplies. • Different techniques: • Flood or Furrow Irrigation • Drip Irrigation • Spray Irrigation

  16. Rangeland • Areas of land that supply forage or vegetation for grazing and browsing animals but are not managed. • Land includes: • Prairies • Desert scrub • Grasslands • Chaparral (shrublands) • Arctic tundra/desert • Open woodlands

  17. Rangeland • Worldwide 40% devoted to livestock • About 25% of the US is rangelands • Areas of low to moderate rainfall (arid, semi-arid)

  18. Environmental Problem • Overgrazing: • Occurs when too many animals graze for too long on a given area, exceeding the carrying capacity of the rangeland • Removes vegetation and compacts soil so it not longer holds water • Increased soil erosion and loss of biodiversity

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