Which important green-house gas, other than methane, is being produced from the agricultural fields?
Arsine
Sulphur dioxide
Ammonoa
Nitrous oxide
In Minamata Bay of Japan, the animals which remained free from Minamata disease are:
Pigs
Rabbits
Dogs
Cats
In a biotic community,the most important factor for survival of an animal is
Day length
Soil moisture
Green food
Predators
Upper part of sea / aquatic ecosystem contains
Plankton
Nekton
Both (a) and ( b )
Benthos
Acid rains are produced by:
Excess NO2 and SO2 from burning fossil fuels
Excess production of NH3 by industry and coal gas
Excess release of carbon monoxide by incomplete combustion
Excess formation of CO2 by combustion and animal respiration
Which of the following is free - living, aerobic, non- photosynthetic nitrogen-fixing bacterium?
Rhizobium
Acetobacter
Nostoc
Azospirillum
Highest DDT deposition shall occur in
Phytoplankton
Sea gull / birds
Crab
Eel
Phosphate pollution is mainly caused by:
Phosphate rock only.
Agricultural fertilizers only.
Sewage and phosphate rocks.
Sewage and agricultural fertilizers.
Soil water available to roots is
Surface water
Hygroscopic water
Gravitational water
Capillary water
When huge amount of sewage is dumped into a river, its BOD will:
Increase
Decrease
Sharpily decrease
Remain unchanged
