Transcription
Hi guys, this is Rameshwar Verma. So today we are going to discuss about water resources. So what is the meaning of water resources? So there are two words: water and resource. So we already discussed earlier, what is the meaning of resource? So resource means anything which helps in our life for betterment, meaning anything in our life which helps us for our betterment, it acts as a resource. Okay. So water, water also plays an essential role in our life. So it is very important. Means, without water, we can't imagine our life. So without water, we cannot imagine life. That's why. Okay. So stay with our video. Okay. Next is, so let us start about water sources. So we know that our earth's surface, on our earth's surface, 71% of the total area is covered with water. 71% water and 29% land. Okay. 71% water and 29% land. That is considered as hydrosphere. Hydrosphere and land is lithosphere, right? One another sphere, that is atmosphere. So we don't need to talk about this now, but let me tell you a little bit here. So hydrosphere, lithosphere, atmosphere, collectively called biosphere, where we live, right? So if any one of these three is missing, then the biosphere will become bad. Meaning life will come into trouble. Okay. So in this chapter, we are going to discuss about the hydrosphere. We need to talk about this 71%. We don't need to talk about the rest. Okay. So we will be going to discuss about hydrosphere. Clear? Okay. Now, sources of water. What are the different sources of water on our earth's surface? So what are the different sources on the earth's surface? Sources of water. Sources of water. So 97% of the total water is covered with oceans, meaning brackish water, salty water. When we hear the name ocean, what comes to mind? Brackish water. Okay. Salty water. Now, the remaining 3% is fresh water. But can we use this 3%? No, absolutely not. So in this 3%, 2.3% is found in the form of ice. In the form of ice. In the form of ice, meaning in the form of polar ice, this is found. How much? 2.3%. So how much is left? Yes, 0.7%. So only 0.7% is considered as fresh water. Fresh water. And this fresh water is also categorized into two divisions: surface water and groundwater. Surface water and groundwater. Okay. So surface water, it contains only 0.03% in the form of rivers, lakes, ponds, etc. So it contains 0.03%, and the groundwater is 0.66%. Meaning underground water. It means here you can see only 0.7% is fresh water out of 100%. Okay. Here we are considering water resources as 100%. Total is 71%, but here we are considering 100%. Okay. Because we are talking about water sources. That's why. Okay. So we need to conserve water. We need to conserve water. So in this chapter, we will discuss about the conservation of water by its different means, as well as irrigation and its advantages and disadvantages. Okay. So why do we need to conserve water? Because the availability of fresh water is only 0.7%. We need to conserve water. We need to conserve water. So why is there a need to conserve water? Because, because the availability of fresh water is very less. Availability of fresh water. Fresh water is very less in quantity. Quantity. Okay. Very less in quantity. And we use water for daily purposes as well as for agricultural purposes, right? So without water, without water, we can't imagine our life. Our life. There is a lot of water, 100%, but 90% is brackish water, which is of no use. Okay. You cannot use it for irrigation purposes because if you use salty water for irrigation purposes, then the plants will be destroyed. Okay. So there is 0.7% left, which is why we need to conserve it. Now let's talk about conservation practices, how we can conserve. Okay. So about the conservation practices. Conservation practices. Okay. So conservation practices. How can we save water? In how many ways can we save water? So first, we need to find out what is the source of water. What is the primary source of fresh water? So you will tell me. Okay. Message me and tell me what is the primary source of fresh water. Okay. Let's go. So what is the primary source? The primary source of fresh water on the earth's surface. Where does fresh water come from on the earth's surface? Yes, good. That is rainfall. Rainfall. So rainfall is the primary source of fresh water on the earth's surface. Okay. So the primary source is coming from here. So whatever is coming from here, we have to save it. Only then can we use it for the future. Okay. So how will we save it? Conservation practices. So that method is watershed management. Watershed management. Right? So we can do it in two ways. One is rainwater harvesting system. Harvesting system. So it is mainly for recharging the groundwater. Rainwater harvesting system's purpose is to recharge groundwater as well as storing water on the surface of the earth. On the surface of [music] earth. Okay. So we can save rainwater in two ways: one is to recharge the groundwater, fill it up again, and then we can use it further. With the help of wells, with the help of tube wells, with the help of different means of irrigation, with the help of submersible pumps, and storing it on the surface of the earth in the form of tanks, ponds, lakes. So we can store it. That is watershed management. Okay. Because rain is the primary source. So first is rainwater harvesting system. Let's discuss about the rainwater harvesting system. Rainwater. Rainwater harvesting system. What is this system? So let's discuss with the help of a diagram. Rainwater harvesting system. So suppose this is your house. Okay. This is your house. This is the roof of the house. So it collects rainwater. Water comes on everyone's roof, then that water flows away, right? Through the drains, it flows away. But we should not let it flow away. So we need to conserve. So here we will install a pipeline, and we will make a tank like this. Okay. And there is a boring that connects to the groundwater. That boring connects to the groundwater. Okay. So watch carefully. It is very important for examination purposes. So it collects rainwater. It collects rainwater. Rainfall. So that collection is considered as catchment. What is this called? Catchment. Okay. So with the help of this pipe, water is stored in this tank. So this pipe is considered as conduits. Conduits. Okay. That is storage facility. Storage. And after storing, it enters into the groundwater. That is recharge. Recharge. So this is a mechanism. This is a mechanism of rainwater harvesting system. This is a mechanism. So this is asked a lot in exams about its mechanism. So there are some processes in the mechanism. First process: catchment. Second one is conduits. Third is storage. And fourth is recharge. So in exams, it can be asked in MCQs to arrange in sequence. What is the mechanism of rainwater harvesting system? Arrange in sequence. So all these things will be given. It needs to be arranged in sequence. So what is the correct sequence? First is catchment. After catchment, conduits are there. Then storage. Then recharge. So this is a sequence. This is a sequence. Okay. So this is the mechanism. First, we collect rainwater, that is catchment, on the roof. After that, through the pipe, it comes into the tank. And in the tank, you have made a boring. So with the help of the boring, that water goes inside. And it recharges the groundwater. And that is the storage. There is a pipe here, right? That pipe is for air purpose. If this pipe is not there, then this water will not go inside. You have studied in physics, right? For this water to go inside, there should be airflow here. Clear? Understood? Very good. Next is storing on the surface of water. Clear? What is rainwater harvesting system? So it is a system. It is a system to conserve rainwater and for recharging groundwater. So with the help of rainwater, we have recharged groundwater, which was what percentage? 0.66%. And why did we recharge it? Just like we deposit money, and then withdraw it from the ATM later. Similarly, we have deposited it here. And later, when there is no rain, we will easily bore here. We will install a motor and take out water. With the help of tube wells or hand pumps, we can take out water. Through different means, in different ways, or by digging a well, we can take out water. So in different ways, we can use it later. That's why we have recharged it. Clear? Next method is storage on the surface of the earth. Storage on the surface of the earth. Earth's surface. So on the earth's surface, how do we store it? Directly, right? Not much of a problem. With the help of ponds. So in villages, many ponds are made, right? Now, under MNREGA, many laborers are engaged in this work, that every village should have a pond for storing rainwater. Okay. Ponds in the form of ponds, lakes, and tanks. Okay. So in many areas, tanks are made. Like in Rajasthan. So there are so many tanks in each and every house to store rainwater. So whenever there is water, the roof is cleaned very well. So if anyone belongs to the Rajasthan area, they will know that in Rajasthan, the roofs are very neat and clean. Why? Because rain falls on them, and that water needs to be stored in the tank below. It is not recharged there. Why is it not recharged? Because the groundwater level there is very low, or non-existent. Because the soil there is not porous. So if it is not porous, then the moisture will be lost. Meaning the water will not stay in it, it will go inside. That's why we use water in tanks. And this storing facility is in the Gangetic plain area. And in all the plain areas, it works. So storage of ponds, lakes, and tanks. So it is considered by different names in different regions. And this is most important for your MCQ purpose. Okay. So, for example, Khatri or Khul in Western Himalayas. So it is considered as Khatri or Khul. So Khatri or Khul is called where? In the Western Himalayas. So in the Western Himalayan region, what is its name? Khatri or Khul. What is the name of storing water on the surface, meaning with the help of ponds and lakes? It is called Khatri or Khul. Bawli or Diggi. You must have heard of Bawli and Diggi in topographic sheets. So it is in the form of a pond. And where is it called Bawli Diggi? In the Gangetic plain area. Gangetic plain area. So what is its name there? Bawli or Diggi. Okay. So similarly, there are different names. Like Johad in the central area. So Johad in Central India. So in Central India, what is it known as? By the name of Johad. Okay. And there are many other names, right? Like Khambu. Like Koram in Eastern Ghats. Eastern Ghats area, it is called Koram. Okay. Now, Surangam in Western Ghats. Surangam in Western Ghats. Surangam in Western Ghats. And Keri Bhandar or Keri in the Deccan Plateau. In the Deccan Plateau. So it is most important. Very important. It can be asked in your MCQs that storage of surface storing water on the surface of the earth is considered as in Western Himalayas. What is the name of storing water in Western Himalayas? That is Khatri or Khul. In the Gangetic plain area, Balis Diggi. Johad in Central. Khambu in Eastern Ghats. Surangam in Western Ghats. Bhandar or Keri in the Deccan Plateau area. Clear? Is the point clear? Absolutely. Very good. Okay. So this is all about in this video. In the next video, we will discuss about irrigation and its different means of irrigation. Right? Traditional methods as well as modern techniques, and what are the advantages as well as disadvantages. Okay. Stay with our video. Thank you and have a nice day.
Hi guys, how are you? Hope you all are doing very well. So today in the video, we will talk about irrigation. Okay. So what is the meaning of irrigation? So irrigation is the watering of plants or crops. Meaning, watering plants and crops is called irrigation. Okay. So what does it mean? So does rain also give water to plants? So is that an irrigation system? No, absolutely not. So rain is not a part of the irrigation system because irrigation is an artificial method. Irrigation is an artificial method. Artificial method for watering to plants and crops. Okay. So why did it become necessary? We need an irrigation system because there is uncertainty of rainfall. So in India, it is not equally distributed among all areas. So in some areas, there is less rain, as we studied in the previous chapter on climate. So in some areas, there is a lot of rain. Okay. So there is uncertainty. Sometimes it rained in one month, sometimes it did not rain in a month. A crop might require water at that time, and it did not rain. So all these are reasons. All these are reasons why we need an artificial method. Because we cannot always depend on rain. So we need an artificial method. The artificial method of watering plants is known as irrigation. So we came up with a new thing: irrigation should be there. Meaning, if it doesn't rain, how will we grow crops? Grow crops, right? Or in different places, there is different rainfall. Somewhere there is more availability of water. So how will we deliver water? So this is the means of irrigation. Okay. So in this video, we will discuss about irrigation and its types, as well as the advantages and disadvantages of different irrigations. So irrigation methods. There are two methods of irrigation, right? That is traditional method. Traditional method or common method, which are very old methods, common methods. And the second is modern. Modern techniques. So there are two methods of irrigation: traditional method as well as modern technique. So in traditional methods, like well irrigation. Well irrigation. Right? Well and tube well. Tube well irrigation. Canal irrigation. And tank irrigation. Tank irrigation. So these are the common methods, traditional methods. From wells, tube wells, canals, tanks. These are the common methods. Okay. The modern techniques are spray. Spray irrigation. Sprinkler irrigation. And the last is drip irrigation. So a point is made about drip irrigation: it is the most essential method of modern irrigation technique. So among modern irrigation techniques, which is the most essential, the most important, is drip irrigation. Why? Because it requires very less water. Very little water is needed. So drip, drip, it gives water to the roots with the help of a pipeline. Okay. So the best technique is considered to be drip irrigation. It can be asked in MCQs, so remember. So let us discuss one by one about well irrigation, tube well, canal irrigation, tank irrigation, about its advantages and disadvantages. Clear? Okay. So we have understood why irrigation is necessary. So because of the uncertainty of rainfall in India, uneven distribution of rainfall among different parts of India, as well as crop requirements. Right? When it requires, then we need to give water. When it is needed, then we need to give water. Just like, suppose we are hungry right now, so we need food right now, right? It's not like we are hungry today and will eat tomorrow. That will cause problems. By then, we will become sick. It means that when it is needed, then only when the crop requires it, and if it doesn't rain at that time, then we will have to use irrigation methods. Let's go. So let us discuss one by one. So in this chapter, we only need to mention the advantages and disadvantages. So this will come in the exam, right? About its advantages as well as disadvantages. Clear? Let's go. Okay. So first is well. Well irrigation. Well irrigation. So what is a well? So a well is a small hole dug in the surface of the earth. So it is a small hole on the surface of the earth for using groundwater. Groundwater. So to use groundwater, this is the surface, suppose you have dug a well here. Right? Here is the water surface. That is a well. Okay. So with the help of a well, we can draw water from here. Absolutely. Right? So we can draw water in many methods. There are different methods. Okay. So in which there are methods like Persian wheels. Persian wheels. Then lever method. And inclined method. Inclined method. Right? So all these methods, Persian wheels, lever method, inclined method, all these are out of order. So all of them have become out of order in the present time. So they are not in practice at present. Okay. So Persian wheels. Earlier, you might have seen that a wheel-like thing was attached to the well, right? And there was a chain attached to it, which was connected to the water. And that chain contained buckets. Like this. That chain contained buckets. When these buckets came into the water, they filled with water, and then they came upwards. Right? There was a drain here, and these buckets would drop the water here. Again, this is a Persian wheel. And this wheel rotates. Right? With the help of an animal, that is an ox. So it was rotated with the help of an ox because it was used for farming purposes. So it would rotate like this. This wheel would move, and water would come out of the well. That is a Persian wheel. Lever method. Same method. Here, from the well, what would happen is that on one side, we would put a lever here, and on one side, we would put a weight. And on one side, you have it. When the weight was pressed down, it filled with water, and then it would come back. This is a lever method. Okay. And the inclined method. Simple, we used to draw water from the well with the help of an animal. Here there was a pulley, and water was filled, and it was directly attached to the animal. It would pull, and water would come out. Okay. So all these methods, Persian wheel, lever method, inclined method, are out of order now. Because now, in their place, what has come? Now, in place of all these, we have used with the help of a motor. So we draw water with the help of a motor. So the motor started drawing water. Now, well irrigation has gradually shrunk into tube wells. Well irrigation has shrunk into tube wells. Meaning, a well is a bit larger, and a tube well is a smaller version of that, in the form of a pipe. Now it is so big. Now we have simply used a thin pipe for it. So it is called a tube well. Okay. And tube well. So now the water that will come out will be inclined with the help of a motor. With the help of a motor. And modern techniques have come. That is submersible. Submersible. Okay. With the help of this, water is now inclined. So Persian wheel, lever method, and inclined method are now out of order. Because now, in their place, what has taken over? The motor and the submersible motor have taken over. Clear? Now, advantages and disadvantages of this.
Irrigation. What are the advantages and disadvantages? Okay. Let's talk about advantages. So, it gives water. It gives water whenever we need it. So, when we need water, when the crop needs water, we will take water from here. That means this is an advantage. Now we won't have to wait, okay? We won't have to wait for rain. If needed, we take water from it. Okay. So, it is also used with the help of a motor. So, we can take water in it with the help of a water motor, right? With it, it is also used with the help of water for inclined water, in-clined water, right? Lifted from great, from great depth. We can also extract water from very great depths. These are advantages, right? And it is at a very low cost. Its cost also comes out to be less. Clear? So, this is the advantage of well irrigation. Now, disadvantages. What are the disadvantages? Okay. So, disadvantages. So, first disadvantage. So, groundwater level varies. Groundwater level varies from different places, different regions. So, in some places, water is found at less depth, in some at very great depth, in some, it is not found at all. So, this is a disadvantage that the ground, the groundwater level is not the same everywhere. This is a disadvantage of this method. Okay. So, it is difficult. It is difficult in hilly areas. Can we dig in hilly areas? We cannot dig. It creates problems. Okay. Now, availability of, availability of electricity. To take water from a motor, what is needed? Electricity and fuel. So, for this, we will have to spend money. Disadvantage of this irrigation method. Okay. So, on one hand, we are talking about advantages, and on the other hand, we are talking about disadvantages. Clear? Next is tube well. Tube well irrigation. Tube well irrigation. So, just like a well, what is a tube well? Just a tube is added to it. What is added? A tube. Tube means that the well which used to take a lot of area, now it is confined to a small area, a small area with the help of a tube. Okay. So, it had a lot of area, right? Now, in this, the area is less. Now, we cannot take water from it by putting a bucket, by putting a vessel. Now, to take water from it, we have two options: one is a motor, and the second is a submersible motor. Okay. So, this is tube well irrigation. Tube well irrigation. That whenever we need it, by running the motor, by running the submersible, we can take water from it. That is, what is the difference between this and that? In that, we could also take water like this, without any cost, without a motor and submersible, without electricity, we could take water from a well. Its cost was less. But in a tube well, without electricity or without fuel, we cannot take water. So, this is its disadvantage. Okay. So, first, let's talk about advantages. Advantages. So, take water. Take water for crops when it requires. When it requires, we can easily take water. This is an advantage, right? So, it is beneficial. It is beneficial. Beneficial for a large area. So, even if your fields are large, right? In that, we used to take water with animals, so irrigation could not be done much. But in this, it is with motor and electricity, so large areas can also be easily irrigated. Watering can be done. Clear? Sorry. Okay. Now, and second, it brings clean water. It brings clean water. So, it gives good, clean water, right? When we need it, we will turn it on. When we don't need it, we will turn it off. Switch on, switch off. Right? This is also an advantage of tube well. What about the disadvantages? Yes, absolutely. So, whatever advantages, whatever problems you understand, you can write them in disadvantages. So, disadvantages. Some things depend on oneself, depend on understanding. So, there is no need to memorize too much. So, you can also write disadvantages yourself. In disadvantages, it requires. It requires fuel and electricity. Without fuel and electricity, it won't run. So, it exploits. It over-exploits. Over-exploits groundwater. Groundwater is over-exploited. That is, if more water is taken out, we will start using more than necessary. Okay. And it is very, very expensive. Expensive. It requires electricity and fuel. Groundwater is over-exploited. So, all these are disadvantages of tube well. Okay. Now, canal irrigation. Canal irrigation. Canal irrigation. Everyone must have seen a canal, right? It is called a canal. So, what is the use of canal irrigation? Why is it needed? When there is tube well, well, then why is canal irrigation needed? Right? So, we know that in tube well or well irrigation, there is a requirement of groundwater. Now, what about those places where there is no groundwater? Right? It creates problems. Rajasthan, Gujarat, and the Haryana area. So, there is a lot of problem there. Right? There is no water there. So, if there is no water, then we will have to dig a canal, right? We will have to take the help of a canal. So, canal irrigation. Okay. So, it is used in those areas where groundwater availability is very low. Groundwater is very low. Clear? Let's talk about canals, right? India's largest canal is the Indira Gandhi Canal. Indira Gandhi Canal is in Rajasthan. Where does it get water from? Bhakra Nangal Dam. This also needs to be remembered. Okay. Indira Gandhi Canal is India's largest canal, and which is the world's largest canal? Suez Canal. It connects the Red Sea to the Mediterranean Sea. So, the Suez Canal, which connects the Red Sea and the Mediterranean Sea, is the world's largest canal, and India's is the Indira Gandhi Canal. So, what are the advantages and disadvantages of canal irrigation? Advantages. Advantages. So, advantages. It fulfills. Fulfills the requirement. Requirement of water in areas where less availability. Availability of groundwater. Less availability of groundwater. Okay. So, it benefits such places where groundwater availability is less. Okay. So, canal irrigation is suitable for poor farmers. Those who cannot afford, right? To install a tube well, electricity, fuel, generator, they cannot afford it. So, for poor farmers, what is canal irrigation? It is an advantage. Now, disadvantages of canal. Disadvantages of canal. What are the disadvantages? So, disadvantages. It requires a huge amount for maintenance. Huge amount for maintenance. So, brother, a very big canal has been built, it costs a lot of money. So, the government does not want to spend that huge amount, and even if it spends, even if the canal is built, it needs to be maintained repeatedly. It needs maintenance. So, there is negligence of maintenance. This is a disadvantage of canal irrigation. Okay. Okay. And so, it also requires a motor. So, to take water, what do we need? We need a motor. We can take from the canal. The government also charges. The government, government charges to farmers. So, for this, the government also charges farmers, takes money. Okay. Takes money for canal irrigation. So, this is all about techniques. Common techniques, traditional techniques. Now, let's talk a little about modern techniques. We will talk about all modern techniques together. And all things will be available in the notes. Modern techniques. So, there are three in modern techniques, brother. Spray, sprinkler, and drip. Spray. Spray means like a sprinkler, right? Yes, you must have seen a spray. So, it is given in the form of a spray from a pipe, so that small droplets are equally distributed on the crop. That is spray. Sprinkler is also the same. With the help of spray. So, in spray, there are very small droplets. In sprinkler, right? You must have seen on grounds, etc., water is applied like this, water comes out, it rotates all around, and water falls equally everywhere. Like this, a pipe is attached, right? At short distances, there is a sprinkler like this, and it distributes water all around. So, this is a modern technique. And the best technique in modern techniques is drip irrigation. Drip irrigation. What happens in drip irrigation is that pipelines are laid in the fields, and there is a point at the roots of the crop. So, water goes drip, drip. So, this is the best method. Best method for what? Best method for irrigation. Why? Because it requires very less water. So, the first shortage is water. So, these modern techniques use less water. That's why they are important. So, very little water is used. This is its advantage. That with less water, more facility is provided, more irrigation can be provided. And the disadvantage is that it is a modern technique, brother. Obviously, if you set up all this, then what will happen? The cost will increase. Money. So, the disadvantage is that it is very costly. So, it is very costly. So, maximum, those developed countries, Israel, Britain, Australia, etc., use this method for more irrigation with less water. Okay. This method has not been brought into much trend in India yet, but it is coming into trend. Okay. Why has it not come into trend? Because its cost is very high, and farmers cannot afford that much. And the advantages are that with less water, more irrigation can be done well. Clear? Hope you liked this video. Stay with our videos. Thank you and have a nice day.