in Environmental Issues by

1 Answer

0 votes
  1. Oil spills:
    Crude oil and refined form enter water bodies during transport of oil, accidental spillages, harbours, coastal industries etc .This is harmful to planktons, fishes and marine plants.
  2. Toxic metals:
     Industrial effluents carry heavy metals like mercury, copper, zinc. lead etc.
  3. Agricultural waste:
    Excess of fertilizers enter into water bodies. Various pesticides, herbicides etc. enter water bodies along with runoff from agricultural fields.
  4. Acids and Alkalies:
    Various manufacturing units and chemical industries and mining operations are responsible for release of acids and alkalies to water bodies.
  5. Soaps and Detergents:
    Waste water from laundry, textile mills and domestic sewage contain large amount of soaps and detergents. They also contain non- degradable pollutants like benzene sulphonates.
  6. Gases:
    Ammonia, Chlorine, Hydrogen sulphide, Ozone, etc. are the main gaseous pollutants.
  7. Radio- active wastes:
    These include harmful radiations from nuclear power stations, drainage from hospitals, industries and nuclear research stations.
  8. Heated effluents (Thermal Pollution):
    Large amount of heated water are released from power stations and various industries and nuclear research stations.
  9. Pathogens:
    From slaughter houses, tanning industries waste water from municipalities may also contain many pathogenic micro-organisms like bacteria, fungi, etc.
  10. Sewage disposal:
    Domestic sewage contains urine, faeces, soaps, detergents, food remains and several other substances along with waste water.
  11. Acid rains:
    It may be secondary effect of air pollution, which alters pH of water bodies.
Biology Questions and Answers for Grade 10, Grade 11 and Grade 12 students, Junior and Senior High Schools, Junior Colleges, Undergraduate biology programs and Medical Entrance exams.