219) Which of the following is true about composition of waste water?
A. Suspended solids e.g. Sand, silt and clay - 0.1%.
B. Colloidal material e.g. Faecal matter, bacteria, cloth and paper fibres - 0.1%.
C. Dissovled materials e.g. Nutrients, (Nitrate, Ammonia, Phosphate, Calcium) - 0.1%.
D. All of the above together constitute 0.1% of the waste water.
227) After the conventional sedimentation, filtering and chlorine treatment, lots of dangerous pollutants still remain. To combat this, the biologists developed a series of six connected marshes when appropriate plants, algae, fungi and bacteria were seeded into this area, which -
A. Neutralise the pollutants
B. Absorb the pollutants
C. Assimilate the pollutants
272) Fill up the blanks:
A. Clouds and gases reflect about ___I___ of the incoming solar radiation, and absorb some of it but almost half of incoming solar radiation falls on Earth's surface heating it, while a small proprotion is reflected back. Earth's surface re-emits heat in the form of ____II____ radiation but part of this does not escape into space as atmospheric gases (e.g. carbon dioxide, ___III____, etc.) absorb a major fraction of it.
B. During the past century, the temperature of Earth has increased by ___I___ most of it during the last three decades. Scientists believe that this rise in temperature is leading to deleterious changes in the environment and resulting in odd climatic changes (e.g. ___II___), thus leading to increased melting of polar ice caps as well as of other places like the Himalayan snow caps.
C. In human eye, cornea absorbs UV-B radiation, and a high does of UV-B causes inflammation of cornea, called ___I____, cataract, etc. Such exposure may permanently damage the cornea.
380) Consider the following statements regarding deforestation
I. It is removal, decrease or deterioration of forest cover of an area
II. It leads to soil erosion
III. Deforestation often causes flash floods
IV. Deforested area can be used variously as cropland, industrial area, residential area, fallow land, etc.
Which of the statements given above are correct?
506) Consider the following statements about pollution
I. Pollution is an undesirable change in physical, chemical or biological characteristics of air, land, water or
soil
II. The air act was amendid in 1987 to include noise as air pollutant
III. In order to control environmental pollution, the Government of India has passed the environment
Protection Act, 1976 to protect and improve the quality of our environment
Which of the statements given above are correct?