According to Odum the light absorbed by the plant cover in terms of kcal/m2/day is:
A. 150
B. 1,500
C. 300
D. 3,000
The maximum amount of CO2 fixed by green plants by way of photosynthesis in a year is:
A. 9 x 1013 kg
B. 8 x 1012 kg
C. 9 x 1011 kg
D. 8 x 1010 kg
Hydrological cycle is under the control of:
A. Grasslands
B. Forests
C. Planktons
D. Epiphytes
The sulphate rocks are formed in ocean by leaching of:
A. FeS and Fe2S3
B. Organic sulphates and -SH
C. Soluble inorganic sulphates
D. All of these
Mark the incorrect statement with reference to carbon cycle:
A. Lime rocks contribute to CO2 of water
B. Atmospheric CO2 gets dissolved in water
C. CO2 is returned by combustion of fuel
D. 75% of total carbon lies in geological component
Ecosystem receives nitrogen from outside through:
A. Biological nitrogen fixation
B. Electrification of nitrogen
C. Industries
D. All the above
Energy transfer from one trophic level to other in a food chain is:
A. 1%
B. 2%
C. 10%
D. 20%
Niche of a species in an ecosystem refers to its:
A. Place of occurrence
B. Competitive ability
C. Centre of origin
D. Function at its place of occurrence
