Unit V:Global Processes- Weather, Climate, Biomes and Land Use Chapter 10 Land-Public and Private.

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Unit V:Global Processes-Weather, Climate, Biomes and Land Use Chapter 10 Land-Public and Private

Transcript of Unit V:Global Processes- Weather, Climate, Biomes and Land Use Chapter 10 Land-Public and Private.

Unit V:Global Processes-Weather, Climate, Biomes and

Land Use

Chapter 10

Land-Public and Private

I. Public Lands in the US

• 42% of US land

publicly held!

Includes

rangelands,

national forests,

national parks,

national wildlife

refuges

and wilderness

areas

• Public Lands managed based on concept Multiple Use: of greatest good for greatest number of people

• Areas are preserved and managed for economic, scientific, recreational and aesthetic purposes.

II. Forest Ecosystems

A. Types of Forest

• Old Growth: uncut or regenerated forest that has not been seriously disturbed by human activity for several hundred years or more. They are biodiversity storehouses because they varied habitat and niches for so many species. (22%)

• Second Growth; stand resulting from secondary ecological succession. 65%

• Tree Plantation: managed tract with uniformly aged trees or one or two genetically uniform species that are harvested and then replanted. (5%)

B. Economic and Ecosystem Services of Forests

C. LoggingAny tree harvest technique has harmfulenviro effects: build roads with resultingerosion and sedimentation, habitatfragmentation, exposure of forest to invasivepests and diseases, loss of biodiversity andunique species.

• Selective cut: Intermediate-aged or mature trees are cut singly or in groups. Reduces crowding, removes diseased trees, encourages new growth and provides trees of all ages for multiple use

Clear Cutting: removal of all trees in an area in a single cut.

Fig. 10-9, p. 198

Fig. 10-11, p. 198

D. Fire

• Fires and Forest EcosystemsSurface Fires: Burn understory and leaf litter; most mature trees and animals ok. Can have eco benefits-reduce fuel, release nutrients, control pests, maintain habitat.Crown Fires: Hot fires start start on ground and eventually burn whole trees and leap from treetop to treetop. Much litter has accumulated, destroy most everything in path (including insects and soil microorgansism) and increase erosion.Smokey the Bear: Although beneficial has given public the view that all fire is bad.

Healthy Forest Initiative: timber companies lobbied Congress; they are allowed to harvest economically valuable medium to large trees in 71% of total area of national forests in return for clearing away smaller more fire-prone trees and underbrush. They are not required to conduct prescribed burns after thinning process and the law exempts them from enviro review

prevention-prescribed burning/ presuppression:

get rid of fuel to prevent a big fire, re-establish jack pine and aspen stands, help control pathogens and insects

- suppression: let fires burn on public land. Tied to HRI which is controversial because it remove large fire resistant trees encouraging dense growth of flammable underbrush and leaves a lot of slash.

http://www.youtube.com/watch?v=2Z8WREzth6g

• Protection From Pathogens and Insects. Cause ecological and economic damage

Integrated Pest Management: Combined pesticide use with other strategies

– Ban wood transfer/Control Spread – Prevention– Remove infected trees– Genetic engineering

Gypsy Moth: a defoliator primarily of hardwood trees, especially oak

• Known to feed on the foliage of hundreds of species of plants in North America but its most common hosts are oaks and aspen; highest concentrations of host trees are in the southern Appalachian Mtns., the Ozark Mtns., and in the northern Lake States.

Mountain Pine Beetle: Defoliator of Lodgepole Pine

Emerald Ash Borer

• The adult feed on ash foliage- little damage. The larvae feed on the inner bark disrupting the tree's ability to transport water and nutrients. Probably arrived in the United States on solid wood packing material originating in its native Asia.

III. Deforestation and the Fuel Wood Crisis

Deforestation and the Fuel Wood Crisis

Population Growth, Poverty force subsistence farming.

Many trees cut for fuel

Large corporations operating under government concession contracts-once trees removed they sell the land to cattle grazers

Corporate Plantations that grow soybeans, palm oil

Tropical Rain Forest Destruction

Causes•Agriculture-cash crops (palm, sugar cane)•Mining•Large Dam Construction•Fuel Wood

Solutions•Corporate Stewardship•Sustainable consumer options•Alternate Products•Policies•http://www.greenpeace.org/usa/en/campaigns/forests/solutions-to-deforestation/

Palm oil ProductionEffects of Producing Palm Oil• 90 per cent of Sumatra’s

orangutan population has disappeared since 1900. They now face extinction

How To Spot Palm Oil in Products

• Palm oil is found in everything from food and household products, food and cosmetics. It is also being used as an biofuel.

• It is thought that one in ten products found on our supermarket shelves today contain palm oil,

• Vegetable oil, Sodium Lauryl Sulphates, Sodium Dodecyl Sulphate, Palmate, Palm Oil Kernal, Palmitate, Stearic Acid, Glyceryl Stearate, Elaeis Guineensis, Steareth-2, Steareth-20, Hydrated palm glycerides, Cety palmitate & ocyl palmitate (anything ending with palmitate)

Two principles upon which U.S. forests are managed• Sustainable Yield• Multiple UseControversial Logging subsidies: Timber companies

get roads built by taxpayer moneyNational Environmental Policy Act (NEPA):

Mandates an environmental assessment of all projects involving federal money or federal permits

Environmental Impact Statement: Before a project can begin, developers must file and EIS to outline the scope and purpose of the project and analyzes the impact of the project

IV. Managing and Sustaining Grasslands

A. Rangeland and Overgrazing• Unfenced grassland in temperate and

tropical climates. Cattle, sheep and goats• Many ecosystem services: soil formation, erosion control, nutrient cycling,

food, habitat and biodviersity• Grass grows from tip not base-will grow back as long as not overgrazed• Too many animals for too long a period of time causes desertificationB. Managing Rangelands• Control number of animals allowed to graze• Rotation • Riparian Zones: thin strip of lush vegetation along river and stram banks.C. Grazing and Urban development in the US West• Much grazing land sold to developers or “urban cowboys”• Conservation easement: land groups formed by rangers and

environmentalists that place restrictions on a deed that bar future owners from developing the land

Ecological RestorationConservation

Controlled Use", "Scientific Management" of natural resources. "Greatest good for the greatest number of people.

Preservation

Remaining wilderness areas on public lands should be left untouched

Restoration

Repair of areas damaged by humans

Replant forest or grassland, restore wetland, stream-bank improvement

Remediation

Most often used with cleanup of chemical contaminants in a polluted area.

Mitigation

Repairing/Rehabilitating a damaged ecosystem or compensation for damage, Most often by providing a substitute or replacement area; frequently involves wetland ecosystems.

Reclamation

Typically used to describe chemical or physical manipulations carried out in severely degraded sites, such as open-pit mines or large-scale construction 

Reconciliation Ecology: method of preserving biodiversity with dwindling areas for preservation

V. Residential Land Use is Expanding

• Suburban: areas surround metropolitan centers and have low population density compared to urban areas.

Urban Sprawl

• Creation of urbanized areas that spread into rural areas and remove clear boundaries between the two.

• Landscape characterized by clusters of housing, retail shops, office parks separated by miles of road

• Caused by autos/highway construction, living costs, urban blight and government policies

• https://www.youtube.com/watch?v=AqUSo2hstHI

Urban Blight

Smart Growth1. Mixed Land Use

2. Range of housing options

3. Walkable neighborhoods

4. Stakeholder decision making

5. Compact building design

6. Distinctive, attractive communities with a strong sense of place

7. Preserve open space and enviro areas

8. Transportation choices

9. Build in existing areas

10. Make development decisions fair and cost effective

http://water.nature.org/waterblueprint/?utm_campaign=social.nature&utm_medium=social&utm_source=twitter&utm_content=1415996021#/section=overview&c=3:6.31530:-37.17773