Class 12th Biology 2017 Set3 Delhi Board Paper Solution
Discuss the role of healthy ecosystem services as a prerequisite for a wide range of economic, environmental and aesthetic goods and services.
Healthy ecosystems are the base for a wide range of economic, environmental and aesthetic goods and services. The products of ecosystem processes are named as ecosystem services.Forests are the major source of ecosystem services and are prerequisite for environmental, aesthetic goods and indir ect economic values in the following ways:
1. Environmental Values
(i) Carbon-fixation Huge amount of CO2 in the atmosphere is removed naturally and fixed by plants in to organic molecules and energy through photosynthesis. All the other trophic levels, i.e. consumers depend upon this energy produced by them.
(ii) Release of oxygen by the producers as a byproduct in the process of photosynthe sis, improves the air quality and supports life on earth.
(iii) Soil Soil formation and soil protection are the major ecosystem s ervices accounting for nearly 50% of their total worth. Plant cover protects the soil from drastic changes in temperature. There is little wind or water erosion as soil particles are not exposed to them. The soil remains spon gy and fertile. There are not landslides and no floods.
(iv) Nutrient cycling There is no depletion of nutrients, but the same are repeated ly circulated.
2. Economic Value
(i) Ecosystem services provide certain economical importa nt products also. These include timber, paper, rubber, wax, medicines, cosmetics, resins, etc.
(ii) Ecosystem also provides other benefits such as aid in po llination. Bees and other insects of natural ecosystem visi t nearby farmlands to pollinate crops.
3. Other aesthetic values Natural ecosystems are a source of spiritual, cultural and a esthetic values.
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Fill in the blanks:
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Explain the following terms with example
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