Impact of development on the quality of Environment
Impact of development Urbanization Cities as an Ecosystem Natural environment Lithologic EnvLithologic Env. Atmospheric EnvAtmospheric Env. Hydrologic EnvHydrologic Env. Biologic Env. Industrialization Air Pollution Water Pollution Thermal Pollution Noise Pollution
Cities as an Ecosystem Biotic components: Man and selected living organisms Abiotic components: Urban environment
Urbanization involve the modification of the environment or/and the impact of the environment The physical environment may influence the form, functions and growth of the city. A change in either the urban environment or the urban man will affect the other component of the urban ecosystem. Cities as an Ecosystem
It is an Open system Cannot self-contained Cannot function in isolation from the other parts of the world Depends on external food supply and investment The change of it will affect the region, the country and the rest of the world
Impact on the lithologic Env. 1.Landslide from cleaning or building on unstable slope 2.Ground subsidence Presence of heavy structural loads Pumping underground water
Impact on the Lithologic Env. 3.Impact of the soil Covered by metropolitan structures (cement) Mineral materials excavated from the earth for construction demands Soil erosion and sedimentation Contamination of soil
Impact on the lithologic Env. 4.Change in relief Remolding of the land by cutting and filling Disposal of waste Refuse dump Dust deposition from settlement
Impact on the atmospheric Env. Atmos. Composition CO, CO 2 SO 2 TSP 200x+, 2x 200x 3x to 7x RadiationSunshine duration-5 to 15% TemperatureWinter minimum+ 1 to 2 degree Wind speedAnnual mean-20 to 30% FogWinter Summer + 100% + 30% PrecipitationTotal+ 5 to 10%
Impact on the atmospheric Env. City Climate 1. Temperature (Heat Island)(Heat Island) 2. Visibility 3. Humidity 4. Precipitation 5. Wind speed and 6. direction change
Humidity Humidity is lower for following reasons: higher temperature Waterproof surface Less water is available for evaporation
Precipitation Precipitation increase Urban atmosphere contains large amount of condensation nuclei. Higher temperature intensifies the thermal convection formation of cloud adiabatic cooling condensation
Wind speed & Direction Three features Wind speed will be reduced for rough surface of the city Turbulence may be created in cities. Air circulation system will be induced by the heat island
Impact on the Hydrologic Env. Change in runoff Surface impervious Lack of vegetation Lower infiltration capacity Increase overland flow
Impact on the Hydrologic Env. Increase the magnitude and frequency of flood Before and after urbanization
Impact on the Hydrologic Env. Reasons: Increase surface runoff. Rapid erosion cause to reduce river s capacity. Straighten the channel will shorten the flow concentration period.
Impact on the Hydrologic Env. Harmful Effects: Degrading water quality Increase in dissolved mineral contents Decrease in oxygen (eutrophication) Water shortage Contamination of water Salt water intrusion Changes in the temperature of water
Impact on the Biologic Env. Wild life is rare Increase in domestic pest Subtracts and adds various type of plants
Pollution Definition: Directly or indirectly through man s activities into the atmosphere, hydrosphere, lithosphere and biosphere of infusions of matter and energy at levels of quantity or intensity appreciably higher than natural levels and usually with undesirable or harmful effects upon environments.
Air Pollution Pollutants Primary Pollutants: S ubstances directly produced by a natural process or human activities. Secondary Pollutants: T hey form in the air when primary pollutants react or interact with other matters.
Air Pollution Pollutants Total Suspended Particulates (TSP) Sulphur dioxide (SO 2 ) Carbon Monoxide, Carbon dioxide (CO,CO 2 ) Nitrogen oxides (NOx - NO, NO 2 ) Ozone (O 3 ) – Secondary Pollutant
Air Pollution Harmful health effects Eyes irritation Respiratory system illness Reduces oxygen transport in body and causing headaches, dizziness and nausea Impair brain function Lung cancer
Air Pollution Other harmful effects (Acid Rain) Degradation of property (devalue) Property damage Corrosion of antiques Harmful effect of tissues Reproductive abnormalities of aquatic life
Air Pollution Control Planning, segregation of industrial and residential land use Using low sulphur content fuel Use device to control pollutants emission (filters, electrostatic precipitators, improved combustion efficiency) Setup air quality standard Legislation and Inspection Setup Environmental Protection Agency (EPA) Setup smoke control area
Water Pollution Definition: Its composition or state is directly or indirectly modified by human activities on a an extent such that it is less suitable for purposes it could have served in its natural state.
Water Pollution Types of Pollutants Direct Toxicity: soluble metal, radio-active substances ….. Oxygen demand: Eutrophication Indirect harm: Heat, suspended matters …. Disease organisms: bacteria, pathogens ….
Water Pollution Sources of pollutants Industrial waste: heavy metals, toxic matters, heat, radio-active substances …. Domestic waste: domestic sewage … Farming waste: pig and poultry waste …. Oil: oil spillage, oil leakage ….. Others: civil works, construction ….
Water Pollution Effects of water pollution Eutrophication -> upsetting balance of the the natural ecosystem Killing aquatic life Impaired recreational sites Harm for farming Shortage of fresh water supply
Water Pollution Solutions : Remove sludge Collecting farming waste Constructing new sewage treatment plants Use incinerators to treat domestic waste Use new technology in industrial production Central waste collection and recycling Legislation Education
Thermal Pollution Power plants and some manufacturing processes use large amounts of water for cooling. Heat water flows in the natural water bodies such as lakes, river, sea ……
Thermal Pollution Effects of thermal pollution of water Reduction of dissolved oxygen (DO) : Oxygen is hard to be dissolved over 30 o C Disturb the timing of fish hatch Kill aquatic life: most fish cannot survive in water over 30 o C and almost no aquatic organisms can survive above 50 o C
Thermal Pollution Effects of thermal pollution of atmos. Change urban micro-climate Enhance the heat island effect
Noise Pollution Definition: Unwanted sound You dont want but I want!
Noise Pollution Sources Aircraft: taking off and landing Traffic: moving and horns …. Construction: compressors, excavators … Domestic: air-conditioners, Hi-Fi, recreational activities ….. Industrial: machines running …..
Noise Pollution Effects of Noise Interfere with sleep Irreversible effects to nervous system Temporary or permanent deafness Brain damage / mental illness
Noise Pollution Solutions Planning: separate industrial zone and airport with residential zone Use new technology in production Legislation Restrict taking off and landing period of aircraft Restrict noise from 11pm to 6am in residential areas Restrict construction period Imposition of speed limits and setup no horns areas Noise industries must setup protection devices: eg. Wearing special helmets Education