Beneficial aspects of the river
River brings water, water supports life

Ch Iboton Singh *

Imphal Turel (River) in September 2012 :: Pix - Jinendra Maibam

Everyday we need water for various purposes. The river water is treated and distributed to the cities and towns through pipelines mainly for drinking purpose. But in the hills and rural areas where there is no water treatment facility the people have to drink the available water directly or boiled and settled before drinking it.

So many of the hill and rural people suffer from water borne diseases. There are innumerable number of rivers on the globe ranging from a few kilometers to a few thousand kilometres long. They carry different volumes of water as per their sizes. The Nile River in Africa is the longest (6,690 km) while the next longest is Amazon River (6,570 km) in South America. There are 27 large rivers in the world having lengths of more than 2700 kms.

In the upper course, the current of water is normally swift and erosion of the river bed and its banks takes place. The eroded materials both in suspension as well as in solution are carried down to the lower course where the current becomes mild and settle the heavier materials. The silt deposited in the valley make the land fertile and suited for cultivation of various crops and vegetables. The lighter materials are further carried down up-to the end in the sea.

So the main works of the river (actually the water) are erosion, transportation and deposition of the materials eroded. Such actions of the river modify the land surface over which it flows. A number of tributaries also join a big river at different points in its course adding to the volume of water.

When men changed their way of life from wandering food gatherers to cultivators, they settled mostly in the river valleys because of the fertile soil, adequate water, abundance of fish, water transport facility, etc. The earliest settlements were made in the Jordan valley 10,000 years ago, in the Indus valley (Mohenjo-Daro) 4000 years ago, in the Ganges valley 3000 years, in the Yangtze and Yellow river valleys 4000 years ago. Similarly, other convenient river valleys had also been occupied by human settlements.

So it is rightly said that "River Valleys had been the cradles of civilization". Even now also many cities, towns and villages are found located on the river banks. The first irrigation system was set up on the banks of the Nile river around 6500 years ago. Irrigation of river valleys are widely taken up in many countries of the world, like China, India, Russia, USA and Pakistan. It is estimated that about 155.7 million hectares of land are irrigated in the world. Dams are constructed across the rivers for generating hydro electric power, to get water for various purposes like agricultural, industrial, drinking, etc.

Rivers have also played a vital role in water transport and communication since long time back. The Amazon River is navigable for about 3700 km, St. Lawrence for about 2100 km and the Yangtze for about 1000 km.

In many rivers, steamers and boats are used for transport and communication purpose. Long and voluminous rivers have shared more activities with the people inhabiting along their courses than those of the shorter ones. Some rivers have beautiful waterfalls which attract the tourists and visitors. There are more than 30 notable waterfalls in the world.

Among them Angel Waterfall in Venezuela (979m) is the highest followed by Tugela Waterfall (948m) in South America as the second highest. But Victoria waterfall in Zimbabwe (24th in ht) and Niagra Waterfall in Canada (31st in ht) are more popular to the tourists. Both of them have large volumes of water and produce more spectacular view than the other taller waterfalls.

The falling water is diffused to white bubbles with the formation of mild cloud on which rainbow is formed in the presence of sunlight. This astonishing view is accompanied by the roaring sound of the falling water. Moreover, the area facing the waterfall is having a cooling effect. Tourists and visitors have enjoyed and fully relaxed in the scene and situation.

The other recreational activities taken up in the river and its banks are fishing, swimming, water sports, camping, rafting, trekking etc. These have attracted the tourists from different parts of the world. Now tourism has become a big industry which can earn a good revenue in spite of its input in the development of infrastructure. Moreover floating markets (on boats) are often found in the rivers which form convenient routes in the populated areas (as done in Thailand, Myanmar etc).

Rivers have their own biological diversity in terms of flora and fauna including reptiles, fishes, amphibians, insects etc. The flora of the river includes microscopic plants (algae) and hydrophytes (floating, submerged and amphibians). Besides these, the river banks also support rich vegetations including trees, shrubs, herbs and grasses. All the land creatures, big and small, living nearby the river including elephants, lions, tigers, bisons, bears, jackals, monkeys, wild boars, birds, snakes etc. use to visit the river regularly for drinking water and also for food.

So the river is so kind and helpful to the terrestrial creatures but man takes more advantage from the river due to his wisdom. Man gets many food and non-food items from the river. The food items include various fishes, vegetables, birds etc. while the non-food items includes boulders, sand, pebbles etc. which are inevitably used in construction of roads, buildings and other structures.

But man has committed the most unkind and irresponsible act by discharging the waste (urban, rural and industrial) carelessly into the river. The result is that the heavily polluted water flowing down is harmful and unsafe for use. So we need to keep the river clean throughout its course. However when the river is in spate, all the wastes and rubbishes lying along its course have been cleaned away down to the sea. This is the natural cleaning of the river.

The network of rivers on the Globe is a chain link in the water cycle. Here one interesting question is that "What is water and from where it comes ?" Water, as we see is a liquid substance which is one of the physical resources with which we live. Life is said to have originated from water and still we depend on it.

Actually water is the essential element for all the creatures on earth. But the miracle is that it exists in three states i.e. liquid, solid and gaseous. Liquid form of water is running water which can be stored in any container or reservoir. Solid form of water (e.g. ice and snow) is still water while the gaseous form of water (e.g. vapour and cloud) is flying water.

A great quantity of water is in continuous cycle from land and sea to atmosphere and then to sea again. Water from the seas, oceans, land surface (including ice) and vegetation evaporate and float in the atmosphere above as clouds. In meeting with the cold winds, they condense and fall as raindrops. Some quantity of the rain falling on the land is evaporated, some quantity is absorbed by the soil, some quantity by the vegetation while the rest goes to the seas and oceans through the network of rivers.

This continuous movement of water is driven by the solar energy and is known as Hydrological Cycle or simply Water Cycle. The total quantity of water involved in the cycle is estimated by the experts to be about 500 million tones. This water cycle distributes fresh water on the land surface of the globe in different seasons of the year to facilitate the existence of life on earth. It also modifies the climate of the area over which precipitation takes place.

The funny behavior of the water is that when it becomes too abundant, flood occurs causing havoc in the area and when it becomes too little, drought occurs and life suffers. Interestingly, 71% of the earth's surface is occupied by water while the rest is landmass comprising of the continents. Nature has rightly designed the presence of such a large quantity of water to sustain life on the planet. No sea or ocean is overflowed by the inflow of water (including rainfall) nor are they dried up at any point of time.

It indicates that the total quantity of global water remains more or less the same. Scientists and experts have estimated the total quantity of global water to be about 13,85,984 x 103 km3 of which 97.3 % is in the seas and oceans as saline water supporting the marine life and 2.7% is in the polar ice and glaciers, snows and glaciers of the high mountains, lakes, rivers, ponds, atmosphere etc. as fresh water. Thus the fresh water available is very limited.

Terrestrial life requires fresh water. In the absence of sufficient water in the deserts and arid lands life is found difficult to exist. In other places there is rainfall in different seasons of the year and rivers also distribute water in different places of the globe. Still we are facing shortage of drinking water.

Men needs more water than other creatures because of their varied uses of water. So wisdom has dictated us to tap and conserve sufficient quantity of water to meet our requirements. Here, it is pertinent to remember the proverb - "God gives the nut but He never cracks it".