With the rise of water temperature, dissolved oxygen
remains unchanged
increases in amount
decreases in amount
is more available to the aquatic organisms
C.
decreases in amount
Dissolved Oxygen (DO) is a relative measure of the amount of oxygen dissolved or carried in a given medium. Water contain very limited amount of dissolved oxygen. It comes from the atmosphere and from photosynthesis by aquatic plants. These aquatic plants and aquatic animals inturn uses this oxygen for respiration and to survive. Temperature inturn effect the solubility of dissolved oxygen in water. Thus, if temperature of water rises the amount of dissolved oxygen get, decreases.
'Kyoto Protocol' is a multination international treaty for
phasing out green house gases
controlling ozone destroying substances
management of hazardous wastes
conservation of biodiversity
During waste water treatment, trickling filter is used for
primary treatment
secondary aerobic treatment
secondary anaerobic treatment
tertiary treatment
During sewage treatment, biogases are produced, which include
methane, hydrogen sulphide and carbon dioxide
methane, oxygen and hydrogen sulphide
hydrogen sulphide, methane and sulphur dioxide
hydrogen sulphide, nitrogen and methane
Phenomenon involving increase in concentration of non-degradable pollutants from lower to higher trophic levels is called
biomagnification
bioaccumulation
biodegradation
bioinvasion
Global warming can be controlled by
Reducing deforestation, cutting down use of fossil fuel
Reducing reforestation, increasing the use of fossil fuel
Increasing deforestation, slowing down the growth of human population
Increasing deforestation, reducing efficiency of energy usage
Relationship between DO and BOD is that they
are directly proportional
are inversely proportional
are not related
always remain equal to each other
