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LAND MANAGEMENT AND CONSERVATION

FARMLANDS

• Land that is used to grow crops and fruit.

• The U.S. contains more than 100 million hectares of prime farmland.

• Urban development threatens some of the most productive farmland.• 1996 – Farmland Protection Program to help protect

farmland in danger of being paved over or otherwise developed.

RANGELANDS

• Land that supports different vegetation types that is not used for farming.• Grasslands• Shrublands• Desert

• Most common use is for grazing of livestock.

RANGELANDS

• Problems on the range• Overgrazing – allowing more animals to graze in an area

than the range can support.• Too many plants are eaten and the land becomes

degraded.• Once the plants are gone, there is nothing to keep the

soil from eroding.

RANGELANDS

• Maintaining the Range• Much of the rangeland in the U.S. is public land

maintained by the federal government.• Land is leased to ranchers.• Limiting herd sizes.• Leave rangeland unused for periods of time so the

vegetation can recover.• Dig several waterholes to avoid overgrazing around a

single waterhole.

FOREST LANDS

• Harvesting Trees• People use lots of wood.• Person in the U.S. uses enough that is the equivalent of

cutting down a tree that is 30 m tall every year.• Three categories of trees:• Virgin forest – forest that has never been cut.• Native forest – forest that is planted and managed.• Tree farms – areas where trees are planted in rows and

harvested like other crops.

FOREST LANDS

• Harvesting trees• Clear-cutting – process of removing all of the trees from

an area of land.• Selective cutting – process of cutting and removing only

middle-aged or mature trees.• Selective cutting is much more expensive, but less

destructive.

FOREST LANDS

• Deforestation• The clearing of trees from an area without replacing

them.• Most countries become severely deforested as

populations expand and the demand for products increases.

• Reduces wildlife habitat.• Increases soil erosion.

FOREST LANDS

• Deforestation• Rate of deforestation is particularly high in tropical rain

forests.• If trees are not replanted, natural resources are steadily

depleted.

FOREST LANDS

• Reforestation• The process by which trees are planted to re-establish

trees that have been cut down in a forest land.• Some farmland that was no longer productive was

reforested and is doing well.

PARKS AND PRESERVES

• Public lands have many purposes.• National parks• Leased to private companies for logging, mining, and

ranching.• Maintained for hunting and fishing• Wildlife refuges• Protecting endangered species

PARKS AND PRESERVES

• Wilderness• An area in which the land and the ecosystems it supports

are protected from all exploitation.• 474 regions covering almost 13 million hectares (32

million acres) in the U.S.• Open to hiking, fishing, boating (without motors), and

camping.

PARKS AND PRESERVES

• Benefits of protected areas• Keeps species from going extinct.• Provide recreation.• Serve as outdoor classrooms and research laboratories.

PARKS AND PRESERVES

• Threats to protected areas• More people visit national parks and wilderness areas

each year and leave their mark.• Litter and traffic jams.• Urban areas and industries are often close enough to

affect them.

PARKS AND PRESERVES