Question

Project file on WATER POLLUTION....
plz ASAP..

Answer 1

Answer:

Hydrosphere covers more than 75 per-cent of the earth’s surface either as oceans (salt water) or as fresh water. Hydrosphere includes sea, rivers, oceans, lakes, ponds, streams etc.

Most of the earth’s surfaces water is in the oceans, which contains about 35 parts per thou­sand of dissolved salt of the remainder, most of fresh water with salt content of 0.2% of found either in lakes and ponds (still water) or in rivers and streams (running water).

Fresh water is also available in the form of rains, snow, dew etc. Hydrosphere covers ground water also. Evaporation of water from oceans, cloud formation and precipitation are responsible for worldwide water supply through hydrological cycles. Water is essential to all life. Life was first originate in water.

Pollution of water is the presence of some foreign organic, inorganic, biological, radiological or physical substances in the water. These substances contaminate water by degrading its quality which may cause health hazard or decrease the utility of water.

There are two principle sources of water, surface water and ground water. Surface water comes from streams, lakes, rivers, shallow wells and reservoirs created by damming. Most surface water contains suspended solids, organic and inorganic substances, microbes and other biota. If these substances are present in water in optimum level, they do not cause pollution On the contrary some of them are useful in improving the quality of water. When the concentration of these materials or organisms are high, they degrade the quality of water and make it unfit for recreational, domestic, industrial or other use.

Some substances like industrial poisons, toxic chemicals and pathologic organisms pollute the water even at very low concentrations. Some pollution occurs naturally in the form of soil erosion, deposition of animal wastes and fallen leaves, solution of minerals in water etc. Much of it is the direct result of human activity.

These influence the fertility or productivity of soil in several ways                          They produce humus by decomposing dead plant and animal material i. They produce humus by decomposing dead plant and animal material

ii. Release minerals (e.g. calcium, magnesium and iron) from organic compounds for recycling

iii. Interconvert ions and molecules to other beneficial forms and

iv. Decompose toxic substances to harmless forms.

All these contribute to soil productivity. Any substance that adversely affects the productivity of the soil is a soil pollutant Soil pollution is also called as land pollution.

Air and water pollution can be spread to long distances. But soil is greatly localized. Any pollution of soil of one field need not always affect the soil of neighbouring field.

Properties of water are:

(i) Water is an excellent solvent,

(ii) It has a high specific heat and this property of high heat capacity of water is functionally important to aquatic organisms, and

(iii) Water possesses the highest heat of fusion and heat of evaporation, collectively known as latent heat, of all known substances that are liquid at ordinary temperature. The latent heat of water moderates the temperature of the biosphere. It also plays an important role in the evaporation of water and its condensation as well and as dew in the hydrological or water cycle

Explanation: