Environmental Science lecture 9

1. Environmental Science
A Study of Interrelationships
Thirteenth Edition
Enger & Smith
Chapter 12
Land-Use Planning
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. Land-Use Planning

3. 12.1 The Need for Planning
 Once converted to intensive human use,
• unavailable for other uses
 Present land use in the United States:
• 52% - Crops and livestock
• 44% - Forests and natural areas
• 4% - Intensive human use

4. 12.2 Historical Forces That Shaped Land
Use
 North America rural
• industrial growth began in last third of the 1800s.
 Cities grew because of:
• Industrial Revolution
– farms to industrial jobs in cities
• European immigrants
– Congregated in cities
– jobs were available

5. Migration from the
Central City to the Suburbs
 As cities grew,
• certain sections within city deteriorated
• Pollution and crowding
– made cities undesirable
 In the early 1900s,
• people moved out of cities
• 1950 - 60% urban population lived in central cities.
• 1990 - 30% urban population lived in central cities.

6. Migration from the
Central City to the Suburbs
Rural-to-urban population shift

7. Migration from the
Central City to the Suburbs
Rural-to-urban population shift

8. Migration from the
Central City to the Suburbs
 Urban sprawl
• Spread low-density, auto-dependent development
• On rural land outside compact urban centers (suburban)
• Characteristics:
– Excessive land consumption.
– Lack of choice in ways to travel.
– Fragmented open space (scattered appearance).
– Lack of choice in housing
– Segregation of commercial and housing
– Lack of public spaces

9. 12.4 Problems Associated
with Unplanned Growth
 Death of the Central City
• less than 10% work in the central city.
 Loss of Sense of Community
• feeling isolated
 Higher Infrastructure Costs
• Extension of municipal services more costly

10. 12.4 Problems Associated
with Unplanned Growth
 Transportation
• As cities grew,
– little thought given to
transportation corridors.
– constant road building.
– Large Metro
– 40 hours/year stuck in
traffic

11. 12.4 Problems Associated
with Unplanned Growth
Loss of Open Space and Farmland

12. 12.4 Problems Associated
with Unplanned Growth
 Air Pollution
• traffic increases, so
does air pollution.
• public transportation
difficult
with highly dispersed
population.
 Water Pollution
– high runoff and potential
flooding.

13. 12.4 Problems Associated
with Unplanned Growth
 Floodplain (low areas near rivers)
• flooding
• Many cities on floodplains
– originally established along waterways.
– Flat land is attractive to developers
– Flood control structures
– Forces water downstream
– floodplain zoning ordinances
– Restrict building in floodplain

14. 12.4 Problems Associated
with Unplanned Growth
Flooding in Floodplain

15. 12.4 Problems Associated
with Unplanned Growth
 Wetlands (like estuaries)
• areas periodically covered with water.
• Many have been drained, filled, or used as landfills.
– U.S. lost 53% of wetlands since the European immigration
– Reproductive phase of many organisms.
– Provide sediment filtration.

16. 12.5 Land-Use Planning Principles
 Land-use planning
•
•
•
•
process of evaluating:
needs and wants of a population,
the land characteristics and value,
various alternative solutions to land uses before
changes are made.
• A basic rule should be to make as few changes as
possible.

18. 12.7 Special Urban Planning Issues
 Urban Transportation Planning
• Four goals:
– Conserve energy and land resources.
– Provide efficient and inexpensive transportation,
– Provide efficient transportation to suburban.
– Reduce urban pollution.

19. 12.7 Special Urban Planning Issues
 Urban open space; recreation planning
• nature centers

20. 12.7 Special Urban Planning Issues
 Smart growth
• Developing “livable” cities and towns.
• Quality of environment directly affects quality of life.
 Principles:
•
•
•
•
•
Mix land uses.
compact building designs (multistory)
Walkable neighborhoods
Preserve open space
Variety of transportation choices.

21. 12.7 Special Urban Planning Issues
 Smart growth
• building of “green
buildings.”
• using recycled
materials,
• ensuring better
ventilation in buildings,
• reducing water and
energy use

22. Environmental Science
A Study of Interrelationships
Thirteenth Edition
Enger & Smith
Chapter 14
Agricultural Methods and Pest Management
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

23. 14.1 The Development of Agriculture
 Development of
agriculture
• manipulating
environment to
produce food
• increase in human
population.
 Mechanized
monoculture
agriculture
• manufacture
pesticides and fertilizer

24. 14.1 The Development of Agriculture
 Problems with mechanized monoculture
agriculture:
• Increases soil erosion.
• Little genetic differentiation
– increased pesticide use.
• No crop rotation depletes soil nutrients,
– increasing fertilizer use.

25. 14.3 Agricultural Chemical Use
 A pesticide
• any chemical used to kill or control populations of
unwanted fungi, plants, or animals (pests).
 Based on the organisms they control.
•
•
•
•
•
Insecticides -- insect populations.
Fungicides---fungal pests.
Rodenticides---mice and rats.
Herbicides --plant pests.
Biocides

26. 14.3 Agricultural Chemical Use
 The discovery of chemicals that could kill insects
• major advance in the control of disease and the
protection of crops.
• Mosquitoes
 In 1942, DDT became the first synthetic organic
insecticide produced.

27. 14.3 Agricultural Chemical Use
 Organophosphates and carbamates
• short-lived pesticides
• do not persist in the environment.
 Affect the nerve cells of humans and other
vertebrates
 Must use special equipment
 receive special training in safe application
practices.

28. 14.3 Agricultural Chemical Use
 Herbicides
•
•
•
•
•
control unwanted plants
heavily used in genetically modified crops.
60% of all pesticides used in U.S.
Weeds compete with crops for soil nutrients
Traditional weed control methods
– expensive in terms of time and energy.

30. 14.3 Agricultural Chemical Use
 Fungicides
• protect agricultural crops from spoilage
• prevent spread of disease
• protect seeds from rotting in the ground
– Methyl mercury is extremely toxic to humans.
 Rodenticides
 prevent poisoning non-target organisms
 Especially humans

31. 14.4 Problems with Pesticide Use
 Persistent pesticides (DDT)
• attached to small soil particles
• easily moved by wind or water.
• distributed throughout the world from local
applications.
• Discovered in polar ice
• present in the bodies of animals, including humans,
throughout the world.

32. 14.4 Problems with Pesticide Use
 Bioaccumulation
• process of accumulating higher and higher amounts of
material within an organism’s body.
– build up in fat tissues.
 Biomagnification
• process of acquiring increasing levels of a substance in
bodies of higher trophic-level organisms.
– DDT, mercury, and PCBs

33. The biomagnification of DDT

34. 14.4 Problems with Pesticide Use
 Pesticide resistance
• Insecticides only kill susceptible individuals.
• Surviving individuals
– characteristics allowed them to tolerate the pesticide.
– Survivors pass on genetic characteristics for tolerance.
– Subsequent pesticide applications less effective.

36. 14.4 Problems with Pesticide Use
 Most pesticides are not species-specific
• kill beneficial species as well as pest species.
• Many kill predator and parasitic insects
– normally control pest insects.
• Insecticides may change the population structure
– species not previously a problem may become a serious
pest.

37. 14.4 Problems with Pesticide Use
 Short-term and long-term health effects
 Acute poisoning during application
 WHO
• 1 million and 5 million acute pesticide poisonings a year
• resulting in 20,000 deaths.
• Farmers exposed to pesticides over many years
– higher levels of certain kinds of cancers

38. Environmental Science
A Study of Interrelationships
Thirteenth Edition
Enger & Smith
Chapter 15
Water Management
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

39. 15.5 Kinds of Water Use
Urban domestic water uses

40. 15.6 Kinds and Sources of Water
Pollution
 Disease-causing organisms
• pollution problem in most of the world.
 Source of these organisms
• Untreated or inadequately treated human or
domesticated animal waste
• Sewage treatment and drinking-water treatment
plants
– reduce this public health problem.

41. 15.6 Kinds and Sources of Water
Pollution
 Point source
• source of pollution readily located… identified.
• Municipal and industrial waste (discharge pipes).
 Nonpoint sources
•
•
•
•
Difficult to identify and control.
Pollutants from agricultural land
Pollutants urban paved surfaces
Acid rain

42. 15.6 Kinds and Sources of Water
Pollution
 Protect surface and ground waters from
nonpoint pollution:
• Use less toxic or nontoxic alternatives to home
chemicals.
• Buy chemicals only in the amount you need, apply as
directed.
• Unwanted household chemicals to hazardous waste
collection centers.
– not pour them down the drain.

43. 15.6 Kinds and Sources of Water
Pollution
 Municipal Water Pollution
• Waste from homes
– organic matter from garbage, food preparation, cleaning of
clothes and dishes, and human waste.
– Fecal coliform bacteria
 Agricultural activities are the primary cause of
water pollution.
• Excessive fertilizer
• Runoff from animal feedlots carries nutrients, organic
matter, and bacteria.

44. Wastewater Treatment

45. 15.6 Kinds and Sources of Water
Pollution
 Factories and industrial complexes
• frequently dispose of waste in municipal sewage
systems.
• may require special wastewater treatment.
 Mining – Industrial water pollution.
• Chemical run-off is released into streams.
• Water draining from mines is highly acidic.

46. Environmental Science
A Study of Interrelationships
Thirteenth Edition
Enger & Smith
Chapter 16
Air Quality Issues
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

47. 16.3 Categories of Air Pollutants
 Primary air pollutants
• released directly into the atmosphere
• sufficient quantities to pose a health risk.
They are:
• Carbon monoxide
• Volatile organic compounds (hydrocarbons)
• Particulate matter
• Sulfur dioxide
• Oxides of nitrogen

48. 16.3 Categories of Air Pollutants
 Carbon monoxide
• organic materials are burned with insufficient oxygen.
• The single largest source is the automobile.
– Remainder from burning, i.e., power plants, leaves, etc.
• Binds to hemoglobin in blood
– makes the hemoglobin less able to carry oxygen.
• It is most dangerous in enclosed spaces

49. 16.3 Categories of Air Pollutants
 Sulfur dioxide (SO2)
• compound of sulfur and oxygen produced when sulfurcontaining fossil fuels are burned.
• Burning coal releases SO2.
• coal-burning power plants.
– U.S. levels of SO2 decreased 56% between 1990 and 2007.

50. 16.3 Categories of Air Pollutants
 Oxides of nitrogen (NOx) are formed when fossil
fuels are burned.
• Nitrogen monoxide (NO) and nitrogen dioxide (NO2)
most common.
• Burning fossil fuels in internal combustion engines
– Primary source of nitrogen oxides.
– Automobiles produce 38%
– Non-road motorized equipment produces 21%

51. 16.7 Global Warming and Climate
Change
 Climatic records indicate over the past 160,000
years
• close correlation between greenhouse gas concentration
and global temperatures.
• Climate change report (2007)
– Average temperature on Earth has increased 0.56 to 0.92°C
(1.0-1.7° F) in the past 100 years
– Sea level is rising about 1.8 mm/yr or 18 cm in 100 years

52. Changes in Average Global Temp

53. 16.7 Global Warming and Climate
Change
 .A strong correlation exists between temperature
increase and amount of greenhouse gases in the
atmosphere.
• Human activity increases greenhouse gases in
atmosphere.
– Greenhouse gases increased 70% btw 1970 and 2004

54. 16.7 Global Warming and Climate Change
 Greenhouse effect:
• Greenhouse gases allow sunlight to penetrate the
atmosphere.
• Sunlight is absorbed by Earth’s surface.
• It is reradiated as infrared energy (heat).
• The heat is absorbed by gases in the atmosphere.

55. 16.7 Global Warming and Climate
Change
Greenhouse effect

56. 16.7 Global Warming and Climate
Change
 Carbon dioxide--most abundant of the
greenhouse gases.
• Deforestation contributes to the amount of carbon
dioxide in the atmosphere.
 Methane
• comes from biological sources and
• from some fossil-fuel burning activities.
 Nitrous oxide
• from fossil fuels and fertilizers.
 Chlorofluorocarbons from refrigerants, and
propellants.

59. 16.7 Global Warming and Climate
Change
 Small increase in the average temperature may
seem trivial
• set in motion changes that could significantly alter the
climate
• Affect:
– hydrologic cycle
– sea level,
– human health,
– survival and distribution of organisms
– use of natural resources by people.