ecology & bio environment geography section 1 Practice Questions Answers Test with Solutions & More Shortcuts

Answer: (a)

Deciduous means “falling off at maturity” or “tending to fall off”, and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe.

In a more general sense, deciduous means the dropping of a part that is no longer needed or falling away after its purpose is finished.

Answer: (d)

Energy generated by using wind, tides, solar, geothermal heat, and biomass including farm and animal waste as well as human excreta is known as non-conventional energy. All these sources are renewable or inexhaustible and do not cause environmental pollution. Moreover, they do not require heavy expenditure.

Nuclear energy usually means the part of the energy of an atomic nucleus, which can be released by fusion or fission or radioactive decay.

Answer: (c)

The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases such as Carbon dioxide, and is re-radiated in all directions.

Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases. Human activities, primarily the burning of fossil fuels and clearing of forests, have intensified the natural greenhouse effect, causing global warming.

Answer: (a)

Productivity is the rate of organic matter or biomass production. The average ocean productivity is about 50 grams of carbon per square meter per year; while, the average land productivity is 160 grams of carbon per square meter per year.

Salt marshes and mangroves have one of the highest productivity of 3300-6000 grams of carbon per square meter per year.

So the correct sequence of the ecosystem in the order of decreasing productivity is:

Mangroves > Grasslands > Lakes > Oceans.

Answer: (d)

Forests are considered as sinks of carbon dioxide. A carbon sink is anything that absorbs more carbon that it releases, whilst a carbon source is anything that releases more carbon than is absorb. It is for this reason that they are indispensable in the present global scenario marked by increasing global warming and climate change.