topics in the field of envt wich are essential

1. OZONE LAYER DEPLETION
ACTION
CAUSES
EFFECTS

2. ACTION:
 Ozone is colourless & toxic gas. Highly
unstable
 Upper strata 90 %
 Checking UV radiations

4. CAUSES:
 CFC – chlorine production 100 times
 Halons – fire extinguisher
 CCL4 – toxic solvent
 HCL
 Methyl Chloroform – clothes metals

9. GLOBAL WARMING

10. GLOBAL WARMING AN HOT ISSUE:
 CO2 - 25%, Nitrous oxide – 19%, Methane –
100%
 Blanket of gases allows sunlight & traps
heat.

11. EFFECTS:
 Rise in temperature – 0.5 deg Celsius
 Climatic Change – loss of 30% annual
rainfall
 Rise in sea level – 15 cm rise for 0.3 deg C
 Bangladesh – 90 % & Kolkata – 50 %
flooding
 Starvation, agricultural loss, flooding, drought

13. THREATS TO BIODIVERSITY:
 Human Population
 Over-hunting
 Habitat loss
 Invasion of non-native species
 Pollution
 Climate change

14. CONSERVATION OF BIODIVERSITY:
 In-situ method – 75 National Parks, 492
Wildlife Sanctuaries, 14 Biosphere
Reserves
 Ex-situ – 2500 Botanical Gardens, 800
Zoos
 Preserve resting & feeding places
 Regulation of hunting
 Protection of migratory animals
 Regulation of international trade of
wildlife

15. ACID RAINS

17. IMPACT OF ACID RAIN:
 Damage to aquatic ecosystems
 Damage to forest ecosystem
 Damage to built environment
 Damage to human health

19. CAUSES OF DESERTIFICATION:
 Over-cultivation: Cash Crop VS Traditional
Agriculture
 Over-grazing: Rearing of cattles
 Unskilled irrigation: sugarcane growing
causing salinisation

20. EFFECTS OF DESERTIFICATION:
 Climate change, water-air-soil pollution
 Loss of global biodiversity
 Loss of biomass & disruption of cycle
 Loss of production increase in poverty
 Economic instability & political unrest
 Threatens health & nutrition
 Danger for sustainability