The hydrosphere is one of the four spheres of the Earth system; the other three are the geosphere or lithosphere (solid rocky part of Earth), atmosphere (gases surrounding Earth), and biosphere (living things).

The hydrosphere consists of all of the water on, in and surrounding Earth. The water in the hydrosphere is distributed among the ocean, glaciers and ice caps, groundwater, surface water and water in the atmosphere in the form of water vapour and clouds. The water is present in all three phases: solid, liquid and gas. Life on Earth depends on the water of the hydrosphere.

Earth is known as the water planet for good reason. More than 71% of Earth’s surface is covered with water. Only a small fraction of the total amount of water on Earth is available for drinking, washing and irrigating crops because most of it is either salty or frozen.

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The global ocean, along with seas and bays, accounts for 97% of all the water on Earth. Ocean water is salty and is not suitable for drinking or other everyday uses. Only 3% of the water on Earth is fresh (not salty). Over two-thirds of the fresh water is in the form of ice, in glaciers, polar ice caps or permafrost. Another 30% of the fresh water is groundwater. This leaves less than 1% of the fresh water, or 0.007% of the total water on Earth, on the surface in lakes and rivers that are easily accessible.

The hydrologic cycle, also known as the water cycle, describes how all the water in the hydrosphere continually moves between oceans, lakes, rivers, land and atmosphere. During the course of the water cycle, water changes state from liquid to gas and back to liquid. The energy that drives the hydrologic cycle comes from the sun. The steps in the water cycle are evaporation, condensation, precipitation, and run-off. Transpiration is an additional element in the water cycle.

• Evaporation is the process by which water on the surface changes from a liquid to a gas state, water vapour. Energy is required for evaporation to take place.
• Condensation occurs when water vapour in the atmosphere cools and collects into water droplets, forming clouds. The water loses energy when it condenses.
• Precipitation consists of rain, hail, sleet or snow falling from clouds back to Earth’s surface.
• Run-off is water from precipitation that flows over the surface into rivers or streams, eventually returning to the ocean.
• Transpiration happens when water vapour returns to the air from the leaves of plants.

Water that does not run-off soaks into the ground and fills the spaces between the soil and rock, becoming groundwater. This water may sometimes be accessed by wells.

The hydrosphere is the total amount of water on a planet. The hydrosphere includes water that is on the surface of the planet, underground, and in the air. A planet’s hydrosphere can be liquid, vapour, or ice.

On Earth, liquid water exists on the surface in the form of oceans, lakes and rivers. It also exists below ground—as groundwater, in wells and aquifers. Water vapour is most visible as clouds and fog.

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The frozen part of Earth’s hydrosphere is made of ice: glaciers, ice caps and icebergs. The frozen part of the hydrosphere has its own name, the cryosphere.

Water moves through the hydrosphere in a cycle. Water collects in clouds then fall to Earth in the form of rain or snow. This water collects in rivers, lakes, and oceans. Then it evaporates into the atmosphere to start the cycle all over again. This is called the water cycle.

The hydrosphere provides an important place for many animals and plants to live. Many gases nutrients e.g. nitrate, nitrite and ammonium ions, as well as other ions,  are dissolved in water. The presence of these substances is critical for life to exist in water.

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Water on the Earth

Human beings, in all stages of their development, have used minerals for their livelihood, decoration, festivities, religious and ceremonial rites. Such indispensable parts are minerals that life processes cannot occur without them (minerals). From a tiny pin to a towering building or a huge ship, almost everything we use, all are made from minerals; even the food that we eat contains minerals.

Although our mineral intake shares only about 0.3 percent of our total intake of nutrients, they are so influential and so significant that without them it is most impossible to utilize the other 99.7 percent of foodstuffs.

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Mineral: An abridged introduction

Mineral has been defined by Geologists as a “homogenous, naturally occurring substance with a definable internal structure.” Ranging from the hardest diamond to the softest talc minerals are found in various forms in nature.

On the basis of their compositions, minerals, that vary in physical properties like colour and hardness as well as chemical compositions, are classified in two groups. (i) Metallic minerals and (ii) Non-metallic minerals.

(i) Metallic minerals: These contain metals which are hard substances that conduct heat and electricity. They possess a characteristic shine or luster and can be beaten into various shapes (are malleable) and can be drawn into wire (are ductile).

As different types of metals have different properties and uses, we use precious metals mainly for making jwellery. Light metals like aluminium and titanium are used in manufacturing cars aircrafts, etc.

Solutions composed of two or more elements (Metallic compounds) are called alloys; an alloy possesses in itself certain influential properties that a constituent metal doesn’t have. Some important alloys are: brass (made of copper and zinc), bronze (made of copper and tin) and alloy steels (steals containing varying amounts of chromium, nickel, magnese, etc.).

Metallic minerals, further, may be ferrous or nonferrous. Ferrous minerals like iron ore, manganese and chromite possess iron ore while a nonferrous minerals does not possess iron but may contain some other metal such as gold, silver, copper or lead.

(ii) Nonmetallic minerals: The minerals without any metal are called nonmetallic minerals as is obvious from the name itself. Examples of such minerals are Limestone, mica, and gypsum. These type of minerals also include mineral fuels like coal and petroleum.

Generally, rather usually, minerals are extracted from ores which are rocks with a high concentration of a particular mineral. Metals are often extracted from their ores by smetting (process of heating beyond the melting point).

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India’s mineral resources

India has a wide variety of minerals. Although the mountains and alluvial plains or northern India are comparatively poor in minerals, the plateau regions, mainly Chhotanagpur Plateau, have the highest concentration of minerals in India.

Distribution and use of minerals

Iron ore: Iron ore, the most significant metallic mineral, issued for making steel. India has got a place in the list of world’s leading producers of iron ore. At the one hand the states like Madhya Pradesh, Chhattisgarh, Jharkhand and Orissa lead in the production of iron ore, and at the other states like Goa, Karnataka and Maharashtra also produce iron ore. India has earned the status of a leading exporter of iron ore because of the high quality of its iron ore.

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Mangenese: Mangenese, a ferrous mineral, is used in the manufacturing of steel and many other alloys. Orissa, Madhya Pradesh, Karnataka and Maharashtra are the main manganese producing States. India, a leading producer of manganese, exports a large portion of its total production.

Bauxite: Bauxite, a nonferrous mineral, is the ore from which aluminium isextracted; it is an important metal because it combines the potency of metals such as iron with extreme lightness and also with good conductivity and mervellous malleability.

Alluminium is used in manufacturing of aeroplanes, automobiles, electric wires, paints, utensils, and many other things. In India, Jharkhand, Madhya Pradesh, Chhattisgarh, and Maharashtra are the leading bauxite-producer States. India, being a leading producer of bauxite, exports a large part of its total production.

Copper: Copper, a nonferrous mineral, is used mostly in the manufacturing of electric wires and machines because it is malleable, ductile and a good conductor, it is also used in chemical industry.

As India does not have enough reserves of this mineral, the country has to import this metal to meet the domestic requirements. Madhya Pradesh, Jharkhand, Rajasthan and Chattisgarh are the chief copper producing States.

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Mica: Mica, a non-metallic mineral, is made up of series of plates or leaves. As a non conductor electricity, mica has got an important place in the electric and electronic goods industries. It is also used in making paints, varnishes etc. India is the largest producer and exporter of mica in the world; the export of mica accounts for more than half of the world’s production and exports most of its own total production. Jhaekan leads in the production of mica in the country; puby mica, a rare variety, is also produced in Jharkhand, Rajasthan and Andhra Pradesh are other important mica-producing States.

Gold: Gold, a metallic mineral, is commonly used for making jwellery. India’s annual production of this mineral is low as it has very limited reserves of gold. Gold mines in the country are confined to the kolar areas in Karnataka, where mining is very expensive because the mines are among the deepest in the world.

Diamond: The precious stone diamond, a metallic mineral, is used in making jwellery; it is also used to make various instruments. Being very hard they are used in drilling hard rocks and cutting glasses. Production in once famous Panna mines of Madhya Pradesh and Golconda mines in Andhra Pradesh has reduced considerably. However, the diamond-processing industry is well developed in Surat (Gujarat) due to which India imports diamonds for processing and exports those processed diamonds.

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Chromite: It is the ore from which chromium is extracted that is used in manufacturing high-grade steel and to plate iron objects to make them rust-proof. Karnataka, Maharashtra, Orissa and Jharkhand are the main chromite producing States. India exports most of its production of this mineral.

Limestone: Limestone, a non-metallic mineral, is a useful resource that is used in the smelting of iron ore in the production of cement and mortar. Bihar, Jharkhand, Orissa, Madhya Pradesh, Chhattisgarh, Rajasthan, Gujarat and Tamil Nadu are the major limestone-producing States of India.

Gypsum: Gypsum, non-metallic mineral, contains calcium and sulpher. It is used in manufacturing cement, fertilizers and sulpheric acid. India’s leading gypsum-producing State are Rajasthan and Gujarat.

Salt: Salt, a non-metallic mineral, is obtained from seas, lakes and rocks. It is used in chemical industry and added to food. India is one of the largest producers and exports of Salt in the world. By evaporating sea water salt is produced in Gujarat, Maharashtra, Tamil Nadu and Andhra Pradesh. Salt is also extracted from Lake Sambhar in Rajasthan. In Himachal Pradesh rock salt is produced.

Although India does produce very limited amount of lead, zinc and silver, the quantities are not enough to meet the requirements of the country.

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Although the words ‘ocean’ and ‘sea’ are generally interchanged, they can differ in meaning. In the names of only five bodies of water is the word ocean included; these five bodies of water are: the Atlantic, Pacific, Indian, Arctic, and Antarctic. So it can be simply put that Ocean are the bodies of salt water that extend between the continents.

Difference between a Sea and an Ocean

One continuous mass of sea water constitutes all the world’s oceans and seas. It is due to largeness of the ocean that humans have divided it up and named the different parts. There are five Oceans and several dozen seas. Seas are smaller than ocean and are partially surrounded by land. However, they are exactly the same thing.

All the oceans are linked together to form a single mass of salt water. The Seas connect the oceans of the world. Seas cover smaller areas the ocean, generally shallower, and are nearer to the land. There are dozens of seas; however, some of the main seas are:

The Red Sea, The Mediterranean Sea, the Baltic Sea, the Black Sea, the Adriatic Sea, the Caspian Sea, the Caribbean Sea, the Bay of Bengal and the Arabian Sea.

It is important to mention here that the Red Sea in the Indian Ocean has the saltiest sea water in the world and it is also the warmest ocean. Part of the Red Sea is known as the Dead Sea. The Dead Sea is surrounded by a hot desert whose fierce heat causes sea water to evaporate faster and in greater qualities.

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Harvesting in the Sea for food

For ages, fish from the Sea has been on the staple diet of man. Fishing is considered to be one of the oldest occupations known to human beings.

Nowadays myriad efficient methods are used in fishing to catch fish; for instance, Sonar systems help boat in tracking shoals of fish. Trawlers haul nets across the sea-bed to catch fish that inhabit at the bottom. Drift netting includes hanging along net curtain across a stretch of sea. In the long-linking method fishes are caught on several pre-laid out long fishing lines.

Fishing boat on order to stay long at sea and supply large qualities of fish to factories clean and freeze the fish that is caught. A major Seaford, Shellfish, is now raised in farms under the sea; along with this Seaweed, used as food in Japan and China, is also raised in these farms.

Each year about 120 million tons of fish are caught. These catches include whales, the huge fish, that are hunted for meat and oil; smaller fish and Shellfish like lobster and Oyster. To trap everything on their path, dredgers and trawlers drag nets on the Seafloor.

However, may people, particularly environmentalists, are concerned that stocks of certain fish are becoming alarmingly low because of overfishing.

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Farms under the Sea

Sounds amazing, but it is true; however, sans farmers or animals. Instead, some types of fish and shellfish are raised in special enclosures, the farms under the sea. They grow faster and bigger than normal in these farms because they are fed specially. The Japanese have developed seaweed farms as it is used in cooking for their food.

The Sea: Storehouse of Valuable Items

Apart from food the waters and rocks of sea, as a huge storehouse of valuable items, supply many chemicals and minerals useful in medicine and industry. Salt, iodine, magnesium and bromide are extracted from seawater.

Sand, gravel and tin and even diamonds are hauled up by dredging vessels from shallow seas. In many parts of the world oil and gas is piped up from the depth of the sea. Nowadays, in order to suck up millions of metallic lumps, called manganese nodules, from the ocean floor special ships are being developed. From manganese nodules are extracted not only manganese but also cobalt, copper, nickel, and other useful substances. In recent times an understanding among world communities has developed that as the mines on land is fast becoming exhausted, human beings would have to depend more and more on the mines of the sea.

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Pearls in the Sea

Oysters and mussels while responding to irritation produce pearls. When between the oyster’s shell and skin gets a piece of grit (gravel or sand), natural pearls are formed; the phenomenon occurs when tissues surround the grit to produce mother-of-pearl layers. Pearls, however, are artificially produced by inserting particles into clam.

As huge quantities of sand and gravel are extracted from the seas for commercial purposes, the sea has become an important source of minerals; pearls come from oysters and diamonds are mined off the coast of Southwest Africa. Gold has also been mined off the Alaskan coast.

The largest pearl, weighted 6.86kg was found from the Philipines in 1936. It is now known as the Pearl of Lao-Tze.

Oil and gas reservoirs in the Sea

From prehistoric times plant and bacteria remains fell to the ocean floor and got gradually covered by layers of mud that under heat and pressure was converted to oil and gas which finally moved up through porous rocks to be trapped by Impermeable rocks.

Hidden in rocks on the seabed valuable resources of oil and gas can be trapped by drilling through the rocks. However, these rocks, first, must be located in water that is shallow enough for drilling to reach it, because only some kinds of rocks contain oil. In the process of identification of these reservoirs are used shock waves that are sent through the seabed and the returning signals distinguish between the layers of the rock.

Once the process of identification of the reservoirs concludes, temporary rigs are set up to ascertain whether the oil is of the right quality and quantity. In place of the rigs permanent oil platforms are built and anchored to the seabed to extract the oil. After being off –loaded from the separate storage tanks into largest tanks oil is sent ashore via pipelines.

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Study of the depth of the Ocean

Scientists and researchers all over the world use underwater craft like submersible submarines and bathyscaphes to study the depths of the ocean. They are specially designed to protect the people present inside from high underwater pressure. Scientists work in them for fairly long period without returning to the surface of the sea.

Submarine

A submarine is a specialized watercraft that operates underwater; they can float at different levels in water because they are fitted with ballast tanks. When the submarine is required to dive, the tanks (the ballast tank) are filled with water that makes it heavy and it sinks. To get it to the surface, the water in the tanks is replaced with compressed air, due to which vessel floats to the surface proving the point that Air is lighter than Water. Navies of the most developed countries employ submarines which are also used for marine and freshwater research.

Submersible

A submersible, almost a mini submarine, is used by divers to explore deep sea and searching for shipwrecks. Submersible are also used to study the marine life at the bottom of the sea-the seabed.

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The Ganges is a trans-boundary river of Asia which flows through India and Bangladesh. The 2,525 km (1569 miles) river rises in the western Himalayas in the Indian state of Uttarakhand and flows south and east through the Gangetic Plain of North India into Bangladesh, where it empties into the Bay of Bengal.The Ganga river has been declared as India’s National River.

The Ganges rises in the southern Himalayas on the Indian side of the border with the Tibet Autonomous Region of China. The Ganges begins at the confluence of the Bhagirathi and Alaknanda rivers at Devprayag. Ganga’s five headstreams—the Bhagirathi, Alaknanda, Mandakini, Dhauliganga, and Pindar—all rise in the northern mountainous region of Uttarakhand state. The five confluences, known as the Panch Prayag, are all along the Alaknanda.

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The place, where Bhagirathi flows out from Gangotri, it called “Goumukh”.

Ganga is the third largest river by discharge. The Ganges is the most sacred river to Hindus. It is also a lifeline to millions of Indians who live along its course and depend on it for their daily needs. It is worshipped as the goddess Ganga.

The Ganges River emerges from the Himalayas at the town of Rishikesh where it begins to flow onto the Indo-Gangetic Plain. The Indo-Gangetic Plain is geologically known as a foredeep or foreland basin.

Many Hindus visit the Ganges River in Varanasi as that city is considered the holiest of cities.Haridwar and Allahabad or Prayag are also on the banks of Ganga. These Two Cities are famous for Kumbh Mela festival. Kumbh Mela is one of the world’s largest human gatherings on planet Earth.

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Illegal mining in the Ganges river bed for stones and sand for construction work has been a long problem in Haridwar district, Uttarakhand, where it touches the plains for the first time.

India is one of the most polluted rivers in the world. Pollution of the Ganges is caused by both human and industrial waste due to India’s rapid growth as well as religious events. Raw sewage is dumped into the river. In addition, many people bathe and use the river to clean their laundry.

The incidence of water-borne and enteric diseases – such as gastrointestinal disease, cholera, dysentery, hepatitis A and typhoid – among people who use the river’s waters for bathing, washing dishes and brushing teeth is high, at an estimated 66% per year.

The Ganga Action Plan, an environmental initiative that was “the largest single attempt to clean up a polluted river anywhere in the world.” The Ganga Action Plan has been described variously as a “failure,” a “major failure”.

The failure of the Ganga Action Plan has also been variously attributed to “environmental planning without proper understanding of the human–environment interactions,” Indian “traditions and beliefs, corruption and a lack of technical knowledge” and “lack of support from religious authorities.”

Namami Ganga

‘Namami Gange Programme’, is an Integrated Conservation Mission, approved as ‘Flagship Programme’ by the Union Government in June 2014 with a budget outlay of Rs.20,000 Crore to accomplish the twin objectives of effective abatement of pollution, conservation, and rejuvenation of National River Ganga.

Major Components of Main pillars of Namami Gange

• Sewerage Treatment Infrastructure
• River-Front Development
• River-Surface Cleaning
• Bio-Diversity
• Afforestation
• Public Awareness
• Industrial Effluent Monitoring
• Ganga Gram

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