KCSE 2017 Q7 EXPLAIN THE IMPORTANCE OF PROTECTING THE FOREST ECOSYSTEM WITH REFERENCE TO THE FOLLOWING. a) a) Climate change (3 marks) b) Biodiversity (6 marks) c) Biotechnology (4 marks) d) Water conservation (3 marks) e) Pollution (4 marks)

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a) Climate change (3 marks)
  •  Promote (regular) rainfall/ precipitation/ prevent desertification;
  • Act as wind breakers;
  • Keep earth temperatures cool/ reduce global warming;
  • Keeps biogeochemical cycles going e g hydrological, carbon, nitrogen, phosphorous, sulphur cycles;
b) Biodiversity (6 marks)
  • Conserve diverse flora fauna;
  • Conserve genetic variety;
  • Prevent extinction of rare species;
  • Source of research/ employment;
  • Aesthetic attracting tourism in foreign exchange;
  • Have impact on culture/ religion/ politics;
  • Food and shelter for other organisms and man;
  • Source of oxygen;
c) Biotechnology (4 marks)
  • Manufacture of medicines/directly used as medicinal
  • Source of food/ food products;
  • Provide fuel (when regulated);
  • Provide paper and related by-products (when regulated);
  • Provide timber (when regulated);
  • Products used in other industries e  tannin, wax, rubber, oil, honey;
d) Water conservation (3 marks)
  • Increased ground water/ high water tables;
  • Adds into rivers/ lakes/ permanency in  existing water bodies/ reservoirs; , 
  • Water towers/ water catchment;
e) Pollution (4 marks)
  • Minimize soil pollution ensuring cover against surface run-off/ wind erosion/ denudation
  • Trees/ vegetation clean the soil surface by absorbing nutrients from decomposed matter e g sewage;
  • Large scale clean-up of polluted air/ dust;
  • Muffle noise pollution;

20 MARKS

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