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Biology Project. 6B 21 Leung Ming Hong 6B 25 So Kam Hei. Air Pollution. Source of air pollution (human). Air Pollutants from: Factory Vehicle Smoking Construction site. Source of air pollution (natural). Volcano eruption produces sulphur dioxide Digestion in cows produces methane
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Biology Project 6B 21 Leung Ming Hong 6B 25 So Kam Hei
Source of air pollution (human) • Air Pollutants from: • Factory • Vehicle • Smoking • Construction site
Source of air pollution (natural) • Volcano eruption produces sulphur dioxide • Digestion in cows produces methane • SO2 and CH4 are air pollutants
There are many kinds of air pollutants • 1. Carbon monoxide and carbon • 2. Unburnt hydrocarbons • 3. Sulphur dioxide • 4. Oxides of nitrogen • 5. Photochemical smog • 6. Repairable Suspended Particulates (RSPs) • 7. Ozone
1. Carbon monoxide and carbon • Carbon monoxide (CO) is a toxic gas • emitted into the atmosphere by incomplete combustion processes • formed by the oxidation of hydrocarbons and other organic compounds. • survives in the atmosphere for about 1 month • will oxidized to carbon dioxide (CO2). • Carbon particles are part of the dark smoke that forms.
Effect • Mainly emitted by vehicles on road • reduce the oxygen-carrying capacity of the blood • Low conc.: dizzy, headache and irritable • High conc.: unconsciousness and death
2.Unburnt hydrocarbons • (Volatile organic compounds) (VOCs) • released in vehicle exhaust gases • emitted by the evaporation of solvents and motor fuels • Effect • Causing cancer • Formation of smog (smoke + fog)
3. Sulphur dioxide • From power stations burning fossil fuels which contain sulphur
Effect • combines with H2O in atmosphere to produce acid rain • SO2 in air is associated with asthma and chronic bronchitis • SO2 emissions effect air quality in urban areas • Low conc. : respiratory tracts and lung diseases • High conc. : cancer and death SO2(g)+H2O(l) H2SO3(aq) Sulphurous acid
Effect • destroy vegetation and degradation of soils, building materials and watercourses Oh, so poor
4.oxides of nitrogen (NOx) • formed during high temperature combustion processes from the oxidation of nitrogen in the air or fuel • From power stations, heating plants and industrial processes • Mostly NO & NO2 N2(g)+O2(g) 2NO(g) 2NO(g)+O2(g) 2NO2(g)
Effect • Irritation of respiratory tracts and lungs • Causing asthma • In the presence of sunlight, it reacts with hydrocarbons to produce photochemical pollutants such as ozone
5. Photochemical smog • Sunlight acts on air pollutants (e.g. carbon monoxide, nitrogen oxides, hydrocarbons) • form a new substance called photochemical smog
Effect • Irritate the eyes • dangerous to people with breathing and heart problems • poisonous to plants • damages rubber, paint and other materials
6. Repairable Suspended Particulates • Solid matter or liquid droplets from smoke, dust, fuel ash, or condensing vapours • Suspended in the air • Particles smaller than 100 micrometers in diameter • Natural: from sea (wind-blown sea-salt ) or soil • Man made: from diesel exhausts, construction activities and factories
6. Repairable Suspended Particulates • Usually hydrocarbon, sulphates, nitrates • These small particles can enter deep into lungs Most of the RSP is carbon
Effect • creating dirt, odour and visibility problems • health effects :risk of heart and lung disease • carry surface-absorbed carcinogenic compounds into the lungs
Installing precipitator in factory • Using unleaded petrol in vehicle How to solve the problem???
7. Ozone • pollutant produced by reaction between nitrogen dioxide (NO2), hydrocarbons and sunlight • powerful oxidizing agent
Effect • persist for several days and be transported over long distances. • irritate the eyes • causing breathing difficulties • is a highly reactive chemical, capable of attacking surfaces, fabrics and rubber materials • toxic to some crops, vegetation and trees.
Introduction • The Air Pollution Index (API) is a simple way of describing air pollution levels.
Uses • enhance awareness of public to air pollution • Alert those with heart or respiratory illnesses, to consider taking precautionary measures
AIR MONITORING STATIONS General Ambient Air Quality Monitoring Station • located on 4 to 6-floor buildings • Represent air quality in areas of high population density A general air quality monitoring station located at Tsuen Wan.
AIR MONITORING STATIONS Roadside Air Quality Monitoring Station • provides information on the level of pollution very close to vehicle emission sources in busy streets and roads. A roadside air quality monitoring station located at Causeway Bay.
AIR MONITORING STATIONS StreetBox Urban Pollution Monitor in foreign country
AIR MONITORING STATIONS The map below shows the locations of air quality monitoring stations
HOW IS THE API CALCULATED? • Measure pollutant concentrations in the air and analysis effect of polluted air on public • Measure pollutants include NO2 SO2 O3 CO and respirable suspended particulates. • Taking the maximum of the subindices among all the parameters measured at that station. Photochemical smog by NOx
Distribution of Hourly API for General Stations for the period October 2004 - December 2004 High 81.8% Medium 17.9%
Distribution of Hourly API for Roadside Stations for the period October 2004 - December 2004 Very high high
Global Warming & Green House effect What are they? • certain gases in the atmosphere (water vapor, carbon dioxide, nitrous oxide, and methane) • More energy is keep in atmosphere • The temperature is increased
Global Warming and Green House Effect Effect • Change in climate, rainfall • Impact on organism on earth • Earth has warmed by about 1ºF over the past 100 years • Increase the temperature will melt the polar ice cap sea level rise • Causes the earth to heat up, just like the inside of a car parked in sunlight • Keeps the plants warm enough to live in the winter. good or not?
As u see, increasing CO2 concentration is related to the increase in temperature
Lichen • Lichen are particularly good indicators of gas pollution in the air Almost all lichen are sensitive to air pollutions. Such as SO2, F2, O3, pH or even metal ion More: http://www.fs.fed.us/r6/aq/lichen/images.htm
Lichen • Lichen + Green algae not found : SO2 conc. >170 mg/m3 • Only green algae : max. 170 mg/m3 • close formations of lichen on the trunk of the tree, even in the cracks : 125-150 mg/m3
Lichen • leaf shaped lobe plates formed by leafy lichen : 60-70 mg/m3 • lichen growing as a little bush or hanging like a beard : 40-50 mg/m3