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| Aquatic Resources |
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| Vast water bodies and large number of flowing waters support the life of aquatic species. Oceans occupying two-thirds of global area have naturally harboured a large wealth of aquatic plants and animals that are being exploited as aquatic resource. The diversity of life is so vast and ecologically sustainable systems are so many in ocean that knowledge of these life forms has grown into a separate branch of science. |
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| While plant and animals living in oceans are called as marine resources (Ocean resources which form 85-90% of total life under water), those living in flowing water like rivers as well as inland standing water like reservoir and ponds are called as aquatic resources (Fresh water resources). |
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| Apart from vast resource of plants and animals, large mineral wealth is also found under oceans. |
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| For e.g., extraction of common salt and shells of molluscs are source of calcium and quick lime. |
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| India is sixth largest producer of fish in world and second in inland fishes. It is estimated that fish and other aquatic marine products contribute around 1% of GDP, as the value of their products rose from 1230 crores in 1980 to 15980 crores in 1998. Fishes have a significant nutritional value and large number of people - especially in cities - have taken to fish eating habits. As much as 10 - 12 lakh people in our country have relied on fisheries for their living. |
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| Aquatic resources are spread in our country as inland fisheries taken up in rivers, their tributaries, canals, ponds, lakes and reservoirs or as marine fisheries taken up in sea / backwaters. |
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| Nearly 29000 Km of rivers are available in our country supported by nearly 1.1 lakh km of subsidiary water channels. Further, inland fisheries can also be taken up in 8 lakh hectares of water bodies (tanks and ponds). But not even 15 percent of such a inland aquatic vast resources is exploited. |
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| Similarly, India is bestowed with 7520 km of coastline with 20 lakh square km of exclusive economic zone for fishing around coastline. High priority is being offered to marine fisheries development with the support for production, marketing, canning the fishes as well as offering suitable training for fishery industry. It is estimated that 39 lakh tons of marine fishes are produced from in exclusive economic zone around the coastal line. |
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| It is estimated that total fish production in our country is of the order of 56 lakh tons during 1999 - 2000. This is in great contrast with total fish production during 1951 (8 lakh tons). It has also earned Rs. 5000 crore in foreign exchange due to exports. However, India has a meager contribution of 9% to total Asian fish production, while Japan and China have contributed 43% and 18% of Asian production respectively. |
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| Not more than 8% of total fish production potential is exploited in marine and inland sectors. As against this meagre potential being put to use, large quantity of fish produced is not able to be stored / canned properly forcing the producers to sell it at cheaper rate. As it is highly perishable product, quick transportation to market, cold storage and canning are most important components required for growth of fish industry. Along with this, scientific fish production requires high tech mechanised boats. All these requirements make fisheries a capital rich profession. The facilities in respect of storage and canning the fishes are limited in our country. |
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| Recently shrimp culture project was launched where in shrimps are grown in protected water for select export markets. |
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| Water problems |
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| The factors contributing to water problems are: |
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| 1) Rise in population and expansion in industry has increased the demand for water. The average per capita consumption of water in a modern society is 350 700 liters per day. |
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| 2) Deforestation has growth reduced the absorption of rain water and this has led to wastage of water by way of floods and also to soil erosion. |
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| 3) A certain degree of purity of water is needed for each use. But with each use. Water becomes more impure. Hence, water cannot be used again and again for the same purpose. |
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| 4) Waste water is not easy to dispose. |
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| 5) Hard water causes encrustation on utensils and other equipments spoiling them. |
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| 6) Water seeping through soil dissolves a variety of salts in it. Rapid evaporation of such ground water with lots of minerals in it brings the salts to the surface. This causes soil salinity, which affects plant growth adversely. |
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| 7) Rainwater with dissolved oxides of sulphur and nitrogen from the atmosphere comes down as acid rain, which is harmful for plants and animals. |
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| 8) Water containing salts more than 3.5 gms per litre is not fit for irrigation. |
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| Conservation of water |
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| The following steps can be followed to conserve water |
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| 1) Careful and economical use of water for domestic and industrial purposes. |
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| 2) Wastage of irrigation water can be minimized by over avoiding over watering, checking leakage in irrigation channels, sprinkler, techniques can be adopted for watering the fields. |
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| 3) A forestation and reforestation of hill slopes helps hold water prevention its loss as floods. |
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| 4) Dams and reservoirs can be built to and store water for later use. |
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| 5) Flood plains of rivers should not be used for cultivation. |
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| 6) Soil erosion should be controlled as topsoil helps retain water, which percolates to become ground water. |
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| 7) Pollution of water in streams and rivers by sewage and industrial waste should be prevented. |
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| Reuse of polluted water after purification should be encouraged. |
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