What is urbanization characterized by
How is urbanziation defined
What are the 2 main causes of stream impairment
1) agriculture
2) urbanization
How many streams and rivers are impaired by urbanization?
-greater than 130,000 km of rivers and streams
Urban land expansion rates are _______ urban population growth rates
- urban growth is becoming more expansive rather than compact
By 2030, global urban land cover will increase an estimated ____
1.5 million km^2
The most rich countries have low _____
Four ways to measure urbanization
1) Urban land cover
2) Urban population density
3) Fragmentation
4) Compactness
Urban land cover (way to measure urbanization)
-total built-up area of cities, sometimes including open spaces within and on the urban fringe
Urban population density (way to measure urbanization)
-ratio of the total city population to the total built-up area it occupies
Fragmentation (way to measure urbanization)
-relative amount and spatial structure of the open spaces that are fragmented by the expansion of cities into surrounding countryside
Compactness (way to measure urbanization)
-the degree to which the city footprint approximates a circle rather a sprawly shape
the gradient paradigm
- works well because of the common structure of urban areas
Urban-rural gradients
-examines the ecological role of humans
Urbanization produces an array of experimental manipulations such as changes in:
Physical effects of urbanization in hydrology
Hydrologic effects of increased impervious surface cover
Stormwater management programs are designed to:
-maintain quality and quantity of stormwater runoff to pre-development levels
NPDES
- controls water pollution by regulating point sources that discharge pollutants into waters of the US
Temperature impacts of urbanization
______% of urban wastewater in developing countries is untreated
80-90
Chemical pollutants
Bacterial densities are ____ in urban streams. Why?
- increased fecal bacteria from waste water treatment and sewer effluent
algal diversity _____ as proportion of urban land use inreases. Why?
- decreases