1. Land
Chapter 14

2. Land Use, Land Cover
Land Use: farming, mining, building cities and highways and recreation
Land Cover: what you find on a patch of land
Urban: land covered mainly by buildings and roads
Rural: land that contains relatively few people and large areas of open space

3. Where we live Before 1850 most Americans lived in rural communities
Industrial revolution changed this pattern
Machinery replaced people in farming and grain mill industry
Better transportation
People had to move to city to find jobs

4. The Urban-Rural Connection
Whether people live in cities or countryside, people are dependent on resources produced by rural areas.
Ecosystem Services: resources that are produced by natural and artificial ecosystems

6. Ecosystem Services
Area of rural land needed to support one person depends on many factors, such as the climate, the standard of living and how efficiently resources are used.
In the United States each person used the services for more than 12 hectacres

7. Ecosystem Services Examples Purification of air and water
Preservation of soil and renewal of soil fertility
Prevention of flood and drought
Regulation of climate
Maintenance of biodiversity
Movement and cycling of nutrients
Detoxification and decomposition of wastes
Aesthetic beauty

8. Urbanization The movement of people from rural areas to cities
In 1960, 70% was urban; by %; now 81% of U.S. population is considered urban
Areas that have grown slowly are usually pleasant places to live because they can handle the growth

9. United States Population

10. The Urban Crisis When cities grow too fast they often run into trouble
A growing population can overwhelm the infrastructure
Infrastructure: roads, sewers, railroads, bridges, canals, fire and police stations, schools, hospital, water mains and power lines
When more people live in an area the living conditions deteriorate.

12. Urban Sprawl
Rapid expansion of a city into the countryside around the city.
Building of suburbs
These people usually commute to work
Each year in the U.S. suburbs spread over another 2.5 million acres of land

14. Development of Lands Marginal Lands: land poorly suited for building
Examples: L.A. and Mexico City
Cities were built with little room to grow, so they have to grow into surrounding mountains or slopes

15. Urban Planning
Land-Use Planning: determining in advance how land will be used
For businesses, factories, recreation, shopping and other infrastructure
Many companies are required to give a detailed report of their plans, and the potential environmental impact of the project

17. GIS Geographic Information Systems
a computerized system for storing, manipulating and viewing geographic data

18. Transportation
Some cities were built after the invention of the car, so planning for such was not as hard
Many cities have to plan for mass transit systems
Save energy, reduce highway congestion, reduce air pollution and limit loss of land

20. Land Management & Conservation
Farmlands: land used for crops and fruit.
The U.S. uses almost 100 million hectacres for prime farmland
These areas are often threatened by urban growth
Farmland Protection Program (1996)

21. Land Management & Conservation
Rangelands: lands that support different vegetation types but are not used for farming or timber
Most common use is for livestock
The current world population growth may require a 40% increase in food production of rangeland from 1977 to 2030

22. Rangelands
Problems
Most damage is done due to overgrazing (allowing more animals to graze in an area than the range can support)
Results in changes in the plant community, once all the plants are gone, there is nothing to keep the soil eroding

23. Rangelands Maintaining the Range:
Sustaining productivity means reducing overgrazing by limiting herds to sizes that do not degrade the land.
Leaving the land to rest, so vegetation can grow
Digging several water holes

24. Forest Lands Trees are harvested for a variety of products
They are also important for ecosystem services, the most important removing CO2 from the atmosphere

25. Forest Lands Harvesting Trees
On average each person used 1,800cm3 of wood per day (in the U.S. we use almost 4x that much)
A 30m (~90ft) tree each year
People in developing countries use trees for firewood

26. Forest Lands Classification of forest trees Virgin Native Tree Farms
Forest that has never been cut
Native
Forest that is planted and managed
Tree Farms
Trees are planted in rows and harvested like other crops

28. Harvesting Trees Clear-cutting Selective cutting
Removing all trees from an area of land
Can cause soil erosion and destruction of wildlife habitat
Selective cutting
Cutting and removing only middle aged or mature trees
More expensive, less destructive

29. Clear Cutting

30. Selective Cutting

31. Deforestation The clearing of trees from an area without replacement
Due to population expansion and demands for timber
Reduces wildlife habitat, causes soil erosion
Rate is high in tropical rain forests
Borneo deforestion

32. Reforestation
The process by which trees are planted to re-establish trees that have been cut down in a forest land
Some parts of the country require reforestation after timber has been harvested from public land
90% of all timber comes from unmanaged forests

36. Parks and Reserves
Wilderness: an area in which the land and the ecosystems it supports are protected from all exploitation
In the U.S. 32 million acres have been designated as wilderness

39. Benefits of Protected Areas
Without protected areas many species would now be extinct
Provide the only place where unspoiled forests, deserts, or prairies remain
Recreation, outdoor
classrooms and
research laboratories

40. Threats to Protected Areas
Litter and traffic in conservation areas
Industry built close
Climate change