UCONN ARE 1110 Exam #2

Pull factors of urban growth

higher income jobs, education, healthcare, cultural opportunities

Push factors of urban growth

farm mechanization, government policies

Problems of cities

poverty, crime, air and water pollution, waste disposal

Urbanization in the US

moving from central cities to suburbs and smaller cities

Improvements in urban US

better working conditions, medical care, environmental quality

Remaining problems in urban US

inner-city poverty, crime, road congestion, auto pollution

urban sprawl

a combination of cheap gasoline, plentiful land and a network of highways that produces dispersed, automobile oriented cities with low population density

Consequences of Urban Sprawl

Increased congestion, loss of open space, pollution, global warming, & nonrenewable resource use

mass transit in US

tax policies favor cars, could put higher taxes on cars, more public investment in mass transit

city planning

creates livable urban areas

regional planning

broader geographic scale, may coordinate work with multiple municipal governments

Zoning

classifying areas for different types of development and land use

urban growth boundaries

place restrictions on development outside a designated area, reduce the cost of infrastructure compared with sprawl

smart growth

set UGBs, walk able neighborhoods, mixed land use, variety of transportation, preserve open spaces, strengthen existing communities

environmental effects of urban areas

resource usage, land use, pollution

land use planning in urban areas

urban growth leads to high land values and property taxes, as open space decreases, urban residents put higher values on their existence

cluster development

houses or apartments are built only on some part of the land (30% is left as open space)

most freshwater is in

glaciers, ice caps and aquifers

freshwater usage

70% agriculture 20% industry

surface water

precipitation that does not infiltrate the ground or evaporate (rivers, lakes, ponds)

Watershed

region from which water drains into a body of water

Groundwater

water beneath the surface held in pores in soil or rock (20% of water)

Aquifer

porous, sponge-like formations of rock, sand or gravel that holds water

recharge zone

any area where water infiltrates earths surface and reaches aquifers

unconfined aquifers

located below a permeable layer of rock and soil called the zone of aeration

confined aquifer

bound above and below by less permeable rock

aquifer depletion

occurs when water withdrawals exceed recharge

consequences of aquifer depletion

water scarcity, aquifer subsidence (land sinks when water is withdrawn), saltwater intrusion

Doctrine of Riparian Rights

(eastern US) take all you need, provided enough is left for downstream users, does not work with water markets

Doctrine of Prior Appropriation

first come first served rule, use it or lose it principle

dam

any obstruction placed in a river or stream to block the flow of water

uses of dams

built to prevent floods, provide drinking water, allow irrigation and generate electricity

disadvantages of dams

displacement of people, no nourishment downstream, small risk of failure, habitat alteration, fisheries decline

reservoirs

artificial lakes, capacity has declined due to sedimentation

Sediment Management Options

prevention (watershed management), structural accommodation (sediment traps), removal (flushing)

solutions to freshwater depletion

increasing supply- temporary

reducing demand- harder but better

desalination

Desalination

the removal of salt from seawater or other water of marginal quality

Distilling

evaporates and condenses ocean water

reverse osmosis

forces water through membranes to filter out salts

decreasing water usage for agriculture

line irrigation to prevent leaks, level fields to reduce runoff, low pressure irrigation pointed downward, drip irrigation

decreasing residential water usage

low flow faucets, rainwater harvesting, gray water, xeriscaping

decreasing industrial water usage

shift to processes that use less water, recycle wastewater, use surface water runoff, patch leaky pipes

soil

mixture of inorganic materials (clay, silt, sand), decaying organic matter, air and living organisms

O horizon

Surface litter: leaves and partially decomposed organic debris.

A horizon

topsoil: partially decomposed organic matter and inorganic minerals

E horizon

leaching layer- minerals and organic matter leach out of this horizon

B horizon

subsoil

C horizon

weathered parent material

R horizon

rock parent material broken down by weathering

soil erosion

movement of soil components, especially litter and topsoil, from one place to another

agents of erosion

wind and flowing water

sheet erosion

uniform layers of soil are peeled off across a field

rill erosion

fast flowing water cuts small channels in soil

gully erosion

extremes form of rill erosion in which small channels merge and become deeper to form gullies and ditches

Desertification

results when land productivity drops by at least 10%

solutions of desertification

land reclamation (reforestation, gully reclamation), prevention (take vulnerable lands out of production and practice soil conservation)

conservation-tillage farming

minimizes soil disturbances (leaving previous year crop residue)

crop rotation

rotating crops restores nutrients and also reduces soil erosion

Terracing

protects steep slopes

contour farming

follows natural land contours on gentle slopes

strip cropping (intercropping)

maintains strips of different vegetation between crops

windbreaks/shelterbelts

protect against wind erosion

consequences of overgrazing

soil degradation and desertification

soil salinization

irrigation water carries salts which may build up to levels that decrease yields or prevent cultivation

Waterlogging

excess irrigation water raises water table and lowers crop productivity

Inorganic fertilizers

mined or synthetically manufactured

organic fertilizers

made of remains or wastes from organisms

compost

a mixture produced when decomposers break down organic matter in a controlled environment