Soil erosion can be prevented by
raising forests
deforestation
excessive use of fertilizer
overgrazing by animals
The process in which liquid water changes into gas is called
precipitation
condensation
evaporation
transpiration
pH value of acid rain is
11-12
3-6
7-8
10-11
Top-soil contains the following
Humus and living organisms only
Humus and soil particles only
Humus, living organisms and plants
Humus, living organisms and soil particles.
Ozone-layer is getting depleted because of
excessive use of automobiles
excessive formation of industrial units
excessive use of man-made compounds containing both fluorine and chlorine
excessive deforestation.
Choose the correct sequences:
CO2 in atmosphere → decomposers → organic carbon in animals → organic carbon in plants.
CO2 in atmosphere → organic carbon in plants → organic carbon in animals → inorganic carbon in soil.
organic carbonates in water → organic carbon in plants → organic carbon in animals → scavengers.
Organic carbon in animals → decomposers → CO2 in atmosphere → organic carbon in plants.
Over the last 100 years global sea level has risen by about
20-25cm
10-12.5cm
25-50cm
15-30cm
An increase in carbondioxide content in the atmosphere would not cause
more heat to be retained by the environment
increase in photosynthesis in plants
global warming
abundance of desert plants
What is the origin of energy that drives the water cycle?
Trees
Water
Mountains
Sun
Which of the following is a recently originated problem of environment?
Ozone layer depletion
Green house effect
Global warming
All of the above
