Biology

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Biology

  1. 1. BIOLOGY CHAPTER 9 ENDANGERED ECOSYSTEM
  2. 2. POLLUTION
  3. 3. AIR POLLUTION
  4. 4. WATER POLLUTION
  5. 5. THERMAL POLLUTION
  6. 6. NOISE POLLUTION
  7. 7.  THERMAL POLLUTION is the REALEASE OF EXCESSIVE HEAT into the environment.  SOURCES : -discharge of hot water from factories, nuclear reactors and electric power station. -glass buildings.  Electronic factories, electric power stations and nuclear reactors use water as a cooling agent.  The water becomes hot and the hot water is then channelled into the rivers or seas causing the temperature of the water to increase.  When the temperature of water is 5 degree Celsius above the normal water temperature, aquatic organisms can die.  The increased water temperature will increase the process of decomposition and thus increase the B.O.D. value. This reduces the concentration of oxygen in the water, causing the aquatic organism to die.  The hot water also reduces the solubility of oxygen in the water. Hence, the concentration of oxygen in the water is further reduced.  Glass buildings reflect the sun’s rays from one building to the next building. As a result, heat is trapped between the glass buildings and increases the temperature in the surrounding area.
  8. 8.  NOISE POLLUTION is THE OCCURANCE OF EXCESSIVE NOISE in the environment that disturbs the tranquillity of life.  Can be measured by decibel (dB) unit.  HUMAN EARS can only RECEIVE SOUNDS LESS than 80 dB  Sources of noise pollution : -aircrafts -trains -construction sites - machines and equipment in factories -traffic
  9. 9.  Effect of noise pollution : -hearing problems (deafness) -ear injury -headaches -emotional and mental disturbances -high blood pressure -psychological problems
  10. 10. SOURCE OF POLLUTION Cement factories, quarries , , sawmills factories and industries, burning of rubbish, motor vehicles Burning of fossils fuels and rubbish, car exhaust fumes POLLUTANT Dust Dust and soot Carbon monoxide Carbon dioxide Sulphur dioxide Nitrogen oxide HARMFUL EFFECT Respiratory diseases Cough and allergy Dirty building Cause haze Reduce visibility Prevent sunlight from reaching the earth's surface and also block the stomata. Hence, the rate of photosynthesis and the agricultural productivity are reduce Cause lung cancer A toxic gas which combines easily with haemoglobin as compared to oxygen. Therefore, it reduces the efficiency of blood to carry oxygen. Causes the greenhouse effect which increases the atmospheric tempereture Changes in climate cause floods, typhoons and drought Polar ice caps melt, causing floods Irritates the eyes, respiratory tract and lungs Damages lung tisuues Causes acid rain Acid rain corrodes metal structure in bridges and limestones of buliding Lower the pH level of soil and water Causes a reduction in the yield of agricultural products and death of aquatic organisms Causes acid rain and effects of acid rain Damages lung tisuues and causes bronchitis and lung cancer Irritates the eyes and respiratory tracts Car exhaust fumes which contain lead Lead Toxic, harmful and non-biodegrable. Hence, lead can accumulate in the body. When, it reaches a high toxic level it can cause retardation in children. Activities of agricultural industry Agrochemical substances Can be passed on in food chains and become concentrated in the body, causing harm to the organism because it is non-biodegrable Hinder the physiological process Toxic in the body Nuclear power stations Radioactive radiations Causes mutation
  11. 11. Causes cancer and genetic diseases Aerosol and foam industries Chlorofluorocarbon (CFC) Causes ozone layer Causes global warming (changes in climate) Skin cancer
  12. 12. SOURCE OF POLLUTION Discharge of domestic wastes into rivers Discharge of industrial wastes Discharge of agricultural wastes (leaching from farms to nearby rivers) POLLUTANT Untreated sewage (faeces and liquid wastes), rubbish and detergents HARMFUL EFFECT Encourage growth of bacteria, causing diseases such as cholera, typhoid and dysentry Number of bacteria increases due to increased concentration of nitrates and phosphates in untreated sewage Bacteria use up the oxygen supply in water to decompose the intreated organic sewage and other organic wastes. This reduces the concentration of oxygen in the river and kills off fish and other aquatic plants and animals. The decomposition of dead plants and fish further increase the population of bacteria in the water. This will reduce the concentration of oxygen in the water. Cause bad odour and unsightly view. Rubbish that is non-biodegrable prevents sunlight from reaching the plants in the river and prevents difussion of oxygen. This threathens aquatic life. High cocentration of detergents also reduces the the concentration of oxygen in the water and threatens the lives of aquatic organism. Organic wastes from remains of oil palms and rubber plantations, toxic wastes from electronic factories such as arsenic, lead, mercury and zinc Contaminate the water physically. Decomposition of organic wastes reduce the Fertilisers and faeces which contain nitrates and phosphates The high concentration of nitrates and phosphates in rivers or ponds results in eutrophication. The nitrates and phosphates promote raid growth of algae, the algae will later use up the oxygen supply in the water, killing fish and other aquatic organisms Agrochemicals such as insecticides, pesticides, Agrochemicals are non-biodegrable, highly toxic and harmful as they can be passed on in the food chains and accumulate in the bodies of aquatic animals and man. These chemicals wastes in significant amounts herbicides and furgicides concentration of oxygen in the water. Accumulation of toxic chemicals that are non-biodegrable through the food chain in aquatic animals and man. These toxic subtances also damage body organs and are harmful to man, causing cancer and mutation.
  13. 13. are poisonous to aquatic animals and can damage the organs in the body, cause cancer and contaminate water supplies. Oil spillage Oil that spills from ships' oil tanks Causes death to all life forms in the sea. Causes death of sea birds and lions. Pollutes the beaches.

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