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Presentation on theme: "ENVIRONMENTAL STUDIES"— Presentation transcript:



3 Class: Mechanical 1 Batch : B By : Id No Enrollment No Krushnaraj [13BEMEG022] [ ] Jayraj [13BEMEG023] [ ] Karan Gohil [13BEMEG024] [ ] Kashif Sheth [13BEMEG025] [ ] Monish Thakkar [13BEMEG026] [ ] Vinit Shah [13BEMEG029] [ ]

4 WATER RESOURCES Table of contents Introduction. Indian scenario.
Water quality problems in India. Sources of water. : 1. Surface water 2. Ground water. Uses of water. Overuse of water. Problems due to exploitation of water resources. Conclusion.

5 INTRODUCTION Water is a vital natural resource which forms the basis of all life . It is the key resource in all economic activity ranging from agriculture to industry. With ever increasing pressure of human population there is severe stress on water resources . About 97% of the earths surface is covered by water and most of the animals and plant have 60-65% water in their body.

6 INDIAN SCENARIO In India, out of total rainfall in an area of 3290 lakh hectare, a rainfall of billion cubic meters anually occurs, out of the total, 41% is lost in evaporation, 40% is lost in runoff, 10% is retained in soil moisture and 9% seeps in for recharging ground water. Of the 40% stream flow water: 8% is used for irrigation 2% for domestic use 4% for industrial use 12% for electric generation Out of total available water resource 1869 bcm, , the usual water resources are only 1122 bcm, out of which 690 bcm is surface water and 432 bcm is ground water. The present per capita available water resouces is 1122 cm and by 2050 it is likely to be reduce to 748 cm.

The shortage of water in the country is slowly affecting the lives of people as well as the environment around them . Some of the major issues that need attention are: As a result of excessive extraction of ground water to meet agriculture, industrial and domestic demands, drinking water is not available during the critical summer months in many parts of the country. About 10% of the rural and urban population does not have access to regular safe drinking water and many nore are threatened. Most of them depend on unsafe water sources to meet their daily needs. Moreover, water shortages in cities and villages have led to large volumes of water being collected and transported over great distances by tankers and pipelines. Ingress of seawater into coastal aquifers as a result of over-extraction of ground water has made water supplies more saline, unsuitable for drinking and irrigation. Pollution of ground and surface waters from agrochemicals and from industry poses a major environmental health hazard, with potentially significant costs to the country . The world bank has estimated that the total cost of environmental, damage in India amounts to US$9.7 billion annually , 4.5% of the gross domestic product . Of this, 59% results from the health impacts of water pollution.

8 SOURCES OF WATER Surface water 1. Ponds 2. Lakes 3. Streams 4. Rivers
5. Storage reservoir 6. Stored rain water Ground water 1. Springs 2. Infiltration galleries 3. Wells - Dug well - Tube well - Artesian well - French well

Ponds: Natural small sized depression formed within the surface of the earth, gets filled up with water, is known as pond.

Lakes: A natural large sized depression formed within the surface of earth, when gets filled up with water is known as lake. The quality of a water in a lake is generally good and does not need much purification. Larger and older lakes provide comparatively purer water than smaller and newer lakes. Self purification of water due to sedimentation of suspended matter, bleaching of color, removal of bacteria etc. makes the lake water purer and better. On the other hand, in still waters of lakes, and ponds, the algae, wee and vegetable growth takes place freely, imparting bad smell, tastes and colours to such waters.

Lakes :

Streams: In hilly generally small amount of water runs off towards the earth. This small run-offs are known as streams. These streams feed their waters to lakes or rives. Quantity of water available in them is very small and sometimes they may even sometimes go dry.

Rivers: Rivers are born from the hills when number of streams combine together. Rivers are the most important sources of water for public water supply schemes.

Rivers: Perennial river Non- Perennial river Those in which water is available throughout the year. Fed by rains during rainy seasons and by snow during summer seasons. It is a source of public supplies directly. Those in which water is not available at all time. Fed by rains during rainy seasons. The construction of a dam is generally adopted and water is used for irrigation and hydropower etc.

Storage Reservoir: These are formed by constructing hydraulic structure like dams across river. That stored water is generally used for irrigation and hydropower. Stored Rain Water: At some places, on the terrace of the buildings rainy season in a big tank and thereafter whenever requirement is there that stored water is used.

16 RAIN WATER HARVESTING It simply means catching and holding rain where it falls and using it. You can store it in tanks or you can use it to recharge ground. Water availability per capita has been on the decline in India. Two reasons have been the increasing demand for water and the increasing population. The quantum of water available to the country being fixed the increasing demand reduces per capita water availability Ground water sources are increasingly getting depleted or are getting polluted. Bore wells are either silting up, getting depleted or are getting polluted. Bore wells are either silting up, getting short of water or are drawing polluted water. It encourages water conservation and self-dependence. India is blessed with adequate rainfall as a whole, yet there are large patches of dry, drought prone area. In many other places the quality of groundwater is not good. In such places rainwater harvesting can provide lifeline water for survival and more. It makes ecological and financial sense not to waste a pure natural resource available in large quantity on one’s roof.


Springs: The natural outflow of groundwater at the earth’s surface is said to form a spring. A previous layers sandwiched between two impervious layers, give rise to a natural spring. It supplies very small amount of water. A fresh water spring

Infiltration galleries: Infiltration galleries are horizontal or nearly horizontal tunnels contructed at shallow depth (3 to 5 m) along the banks of the river through the water bearing strata. Wells: A water well is a hole usually vertical, excavated in the earth for bringing ground water to the surface . Wells are of many types . They are (a) Dug wells or open wells: Open wells are generally open masonary wells having bigger diameters and are suitable for low discharges of 1-5 litre/second . The yield of an open well is limited because it can be excavated only to a limited depth where the ground water storage is limited.

(b) Tube well: It is a long pipe or a tube . It is bored or drilled deep into the ground intercepting one or more water bearing stratum. (c) Artesian well: When a well is constructed in a pervious layer which is bound between two impervious layer, the water comes on the surface with some pressure at which it is stored in the layer.

d) French well or radial well: It is a special type of well in which surface water is collected from the river bed . A natural or radial perforated pipes are laid with slope towards the center below the bed level of the river . A well will collect the water at the center then it is pumped out with the help of a pump.

22 USES OF WATER (A) Consumptive Use:
Most of water is utilized or consumed in this type of use of water e.g. Irrigation use: Water is required for the growth of vegetation and crops. The need of water is cyclic and will vary from types of crop, plant, tree etc. The water will be taken through the root system and surface water will be lost as evapo-transpiration losses. The water need for each crop will be different quantities even their time of demand is also varying. The water need for rice and sugar cane is two modes. The water requirement in tons of water for one ton of particular crop and total depth of water applied on the irrigated land.

23 USES OF WATER (B) Partial consumptive use:
Water is partly consumed and part of it is wasted as used water. 60% to 80% of water supplied to home is wasted. Part of waste water can be reused. They include water need for Domestic or public water need Fire water need Institutional water needs Industrial water needs Thermal and nuclear power generation water needs

24 USES OF WATER (c) Non consumptive use: There is no direct consumption of water. Sometimes there will be loss of water due to evaporation from the storage at source and point of use. They include: Hydro Electric Power Production In land Navigation Pollution control Recreational life

25 OVERUSE OF WATER Water is used by every living organism on the earth. The requirement of everybody varies. People should utilize it economically, but the situation is different for human beings. Water requirement for man is maximum on earth. Population growth has created much demand of water. Expansion of business activity ranging from industrialization to services such as tourism and entertainment continues to expand rapidly.This expansion requires increased water services including both supply and sanitation, which can lead to more pressure on water resources and natural ecosystems Due to rapid urbanization more people move towards urban areas which leads to overuse of water in urban areas.

Problems related with overuse of surface water: Decrease in flow of water in stream and rivers. Wet land surface reduction. Water logging. Migration of people. Problems related with overuse of ground water: A heavily pumped well can lower the local water table as a result of which shallower wells go dry. Heavy pumping, on a broader scale, can deplete a whole aquifer.

27 CONCLUSION Thus we conclude that we should save water and use it judiciously. Moreover we should not unnecessarily waste water. SAVE WATER SAVE EARTH

28 FOOD RESOURCES Table of contents Introduction Sources of food.
Global/world food problems. Undernourishment. Malnutrition or malnourishment. Indian food scenario. Steps to improve food production. Limits of increasing food production. Loss of genetic diversity limits crops yields. Limits in cultivating more land. Environmental effects/impact of agriculture. Impacts of traditional agriculture on environment. Impacts of modern agriculture on environment. Fertilizer related problems. Problems related to pesticides. Water logging. Salinity problem

29 INTRODUCTION Food is one of the basic requirements of human being, it is the most important material that our body needs for its proper functioning and well being at all stages of our life. Human diet is not restricted to any special category of food. Man eats a variety of foods, of plants and animal origin, as no single food provides us with all the nutrients that we need.

30 SOURCES OF FOOD Our main food resources are:
Agricultural crops (mainly rice, wheat ,maize ,potato ,soyabean ,millet ,sugarcane , barley, oats etc.)Amongst these rice, wheat and maize are the major food grains, about 1600 million metric tons of which is grown each year, which is half of all the agricultural crops. Domesticated animals(cattle, sheep, goat etc.)These animals are the source of milk and meat. These form the important component of the diet of the people all over the world. Aquaculture(fish and sea food.)It is the production of food from aquatic habitants- marine and fresh water. Fish and sea food contribute about 70 million metric tons of high quality proteins to the worlds diet.

During last 50 years food production has increased by about 50% . But at the same time the population growth rate in less developed countries has out stripped food production . The international commission on irrigation and drainage estimated that current food production would have to double within the next 25 years. The FAO estimated that about 840 million people remain chronically hungry, nearly 820 million of them in the developing countries. There are generally two kinds of food problems across the world. Undernourishment. Malnutrition.

32 UNDERNOURISHMENT It is the lack of sufficient calories in available food, so that one has little or no ability to move or work. The FAO estimates that the average minimum daily caloric intake over the whole world is about 2500 calories per day . People who receive less than 90% of their minimum dietary intake on a long term basis are considered undernourished. Those who receive less than 80% of their minimum daily caloric intake requirement are considered “seriously undernourished”. This can be prevented with a better diet, clean water and simple medicines.

Malnutrition is the lack of specific components of food such as proteins, vitamins or essential chemical elements. It is due to nutritional imbalance caused by a lack of specific dietary components or an inability to absorb or utilize essential nutrients .

Major problems due to malnutrition are: Marasmus: Lack of proteins and calories. Kwashiorkar: Lack of protein in the diet which leads to stunted growth in infants and causes failure of neural development and learning disabilities. Anemia: Caused by an inability to absorb iron. Goiter and Hypothyroidism: An iodine deficiency in the diet in early child hood can cause abnormalities such as mental retardation and deaf mutism. Pellagra: Deficiency of tryptophan and lysine vitamins. Chronic hunger: Which occurs when people have enough food to stay alive but not enough to lead satisfactory and productive lives. High malnutrition in africa

35 INDIAN FOOD SCENARIO Although India is the third largest producer of the staple crops an estimated 300 million Indians are still undernourished. India has only half the land as USA, but it has nearly three times the population to feed. India's food problems are directly related to population. Here we can see the projected demands of various food products in india and the idea of growth rate needed to achieve the domestic demand by 2020.

Available land acreage should be properly and judiciously utilized. Soil fertility should be increased through wise use of fertilizers and organic manures. Mixed cropping should be practiced whenever possible . Crop rotation should be done. Soil erosion and loss of nutrients should be prevented by maintaining vegetation cover throughout the year. High yield and disease resistant plant varieties should be introduce. Integrated and balance use of available water resources (surface and ground) should be made.

There are ecological limits to how much food can be produced ,and there are growing signs that such limits have been or soon will be reached in some parts of the world . Even if agricultural technology and biotechnology enhance productivity ,the environmental impacts associated with food production impose limits on amount of food the earth can produce. Continuing to increase inputs of fertilizer , water and pesticides eventually produces no additional increase in crop yields as the J-shaped curve of crop productivity slows down , reaches its limits , levels off and becomes as S-shaped curve . Grains yield per hectare are still increasing in almost every country , but at a much slower rate . Worldwide , such yields dropped from an annual 2.3% increase between 1950 and 1984 to 1% annual increase between 1984 and Since 1985 yields for the major grains in three counties with highest yield per hectare - USA(corn) , Great Brtitain (wheat) , Japan (rice) , have leveled off.

Industrialized agriculture accelerates the loss of biodiversity that can be limit of genetic raw material needed for future green and gene revolution. For example in India ,which once had 30,000 varieties of rice, more than 75% of all rice production now comes from 10 varieties. We are rapidly shrinking the world’s genetic “library” just when we need it more.

Between 1980 and 1990 the area of world’s cropland expanded by only 2%. Theoretically, the world’s cropland should be more than doubled by clearing tropical forests and irrigating arid land; about 83% of those potential new cropland is in the rain forests and savannah grasslands of South America and Africa. The conversion of grainland into non-farm uses and to high-value crops has resulted in to 52% drop in grainland in Japan since 1960. Since 1970s South Korea lost 42% of its grainland and Taiwan 74%.

In the early years of human existence on this earth, man was just a hunter, gatherer and was quite like another animal species . Some ago he took to agriculture by cultivating plants of his own choice . He used the practice of slash and burn cultivation or shifting cultivation. The type of agriculture practiced these days is very different from the traditional ones and their outs in terms of yields as well as their impacts on the environment shows lots of difference. Now the effect on agriculture is divided into two parts: Impacts of traditional agriculture on environment. Impacts of modern agriculture on environment.

Traditional agriculture usually involves simple tools, naturally available water, organic fertilizers and mixed up crops . This is more near to the natural conditions and usually it results in low production. The main impacts of this type of agriculture are as follows: Deforestation :- The slash and burning of trees in forest to clear land for cultivation and frequent shifting result into loss of forest cover.

Soil erosion :-Clearing of forest cover exposes the soil to wind, rain, and storms, thereby resulting in loss of top fertile layer of the soil. Depletion of nutrient:-During slash and burn the organic matter in soil gets destroyed and the most of the nutrients are taken up by the crops within short period, thus making the soil poor in nutrient, which make the cultivators shift to another area.

Modern agriculture makes use of hybrid seeds of selected and single crop variety, high tech equipments and lots of fertilizers, pesticides and irrigation water. The food production has increased tremendously as evident by “green revolution”. However , it also gave rise to several problems as below :- Fertilizer related problems. Problems related to pesticides. Water logging. Salinity problem.

Fertilizer are materials added to soil to restore and enhance the soil productivity for better growth of plants. Excessive use of fertilizer causes problems like: Micronutrient imbalance : Most of the chemical fertilizers used in modern agriculture have nitrogen, phosphorous and potassium (N,P,K)which are essential micronutrient. Excessive use of fertilizers cause micronutrient imbalance which affects the productivity of the soil. Nitrate pollution : Nitrogenous fertilizers applied to the fields often leach deep into soil and ultimately contaminates the ground water. The nitrites get concentrated in the water and if their concentration exceeds 45 mg/l, they cause “Blue Baby diseases” or methamoglobinemia. A person suffering from methamoglobinemia

Eutrophication: Excessive use of N and P fertilizers causes problem related to water bodies like lakes . A large portion of nitrogen and phosphorous present in the fertilizers is washed off and along with run off water reach the water bodies causing over nourishment of the lakes which is called eutrophication. before eutrophication after eutrophication

Chemical compounds that are used for control of pests are called pesticides have gone a long way in protecting crops from the huge loses occurring due to pests , yet they have number of side effects as discussed below. Biological magnification. Death of non target organisms. Creating resistance in pests and producing new pests.

Biological magnification : Many of the pesticides are non biodegradable (for example DDT) and keep on accumulating in the food chain, a process called a biological magnification. Death of non target organisms : Many pesticides are broad spectrum poison which not only kill the target species but also several non target species useful to us. Creating resistance in pests and producing new pests : Some individuals of the pests species usually survive even after pesticide spray . The survivors give rise to highly resistant generations . About 20 species of pests are now known which have become immune to all types of pesticides and are known as “super pests”.

48 WATER LOGGING Over irrigation of croplands by the farmers for good growth of their crop usually leas to water logging . Inadequate drainage system causes excess water to accumulate underground and gradually forms a continuous column with the water table. Under water logged conditions , pore spaces in the soil gets completely filled with water and no air left in the pore spaces. The root of the plants does not adequate air for respiration . As result the yield of crop decreases.

49 WATER LOGGING Preventive measures:
Preventing excessive irrigation, sub-surface drainage technology and bio drainage with trees like eucalyptus are some of the remedial measures to prevent water logging. Eucalyptus trees Sub-surface drainage

50 SALINITY PROBLEM A major cause of Salinization of soil is excessive irrigation . About 20% of worlds cropland receive irrigation with canal water or ground water which unlike lake water often contains salts. Under dry climatic conditions the water evaporates leaving behind salts in upper layer of the soil. At present one third of the total cultivable land area of the world is affected by salts.In India 7 million hectares of land are estimated to affected by salinity. Most of the crops cannot tolerate high salinity so the yield of crop decreases. Remedy: The most common method for getting rid of the salts is to flush them out by applying more quantity of good quality water to such soils.

51 CONCLUSION Thus we conclude from this that we should not waste food resources . We should use natural fertilizers in place of artificial fertilizers. If we will waste the food and exploit the food resources then one day there will be no food to eat and mankind will face threats of extinction.

52 THE END Reference from environmental studies by B.R. SHAH and SNEHAL POPLI. Images taken from google.


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