Watch videos with subtitles in your language, upload your videos, create your own subtitles! Click here to learn more on "how to Dotsub"

Interaction-2_Video-2

0 (0 Likes / 0 Dislikes)
www.makemegenius.com If you want to see more science videos, go to www.makemegenius.com. Yeah, it is free. Wow, you're a good dancer. It seems like you really love fruits. But, did you know that in the future we may not have any fruits? In fact, we may not have any food at all. Yes, you're right. No fruits, no food. Now, one question! Do you know where all fruits and food come from? You're right! All food comes from plants. But, do you know where plants grow? You're right! Plants grow on our planet earth, on the earth's crust. But, did you know? We're not able to grow plants everywhere on the earth's surface. The area where we can grow food is very, very limited. Okay, you don't believe me? Let's use that apple and knife as an example. Think of the apple as the planet earth. Now can you tell me how much of the earth is covered with water? Yes, you're right! If we cut the earth apple in 4 parts, 3 of those parts would be water. So, we can't grow any food plants there. So, only one fourth of the earth there is land. But, again we can't use all the remaining land not covered by water to grow food either. Do you know why? You're right! On half of this available land, we have mountains, deserts and ice. So, we can't grow any plants for food there. So, let's cut this piece of apple into 2 parts. Now, we're left with an eighth part of an apple. One eighth part of the earth. Now, on this part, we have cities, buildings, roads, and a place to grow plants for food. Did you know only one fourth of this part is available for growing plants? Uhh, you look worried. So, this is the only piece of land where we can grow our food. But, did you know? We can only grow food on the top soil of the land. Please peel this piece. So, this little piece of skin is the only place where we can grow food. Oh, you're saying we also have that part available for growing food. Ah, for that you need to understand the soil profile. Only on top soil, can we grow plants. Come with me into the garden, and let's understand why only top soil can be used for growing plants. Wow, is that your rabbit? That's why you brought carrots. Oh, he can help us here! Look at the soil in this garden. Our soil has 4 layers. These layers are Top Soil, Sub Soil, Parent Material, and Bedrock. Can you ask your rabbit to dig a hole for us in the soil? Rabbits make their homes in the soil by digging holes. They can dig really, really fast. Great, he is really quick! Ah, I see you are rewarding him by giving him the other carrot. Now, let's look at different parts of the soil. The part in which your stick is showing is called the Top Soil. Plants and trees grow here. It is very rich in nutrients which are good for plant growth. It also contains lots of worms which are helpful for plants. The upper part is called the Humus which has a lot of dead leaves and dead animals. These dead leaves and animals are slowly decaying with the help of soil bacteria. This process helps form organic nutrients which are necessary for plants to grow. This part is called Sub Soil, and has small particles of rock. This part is called Parent Material. These are the parents rocks which get broken down slowly, and becomes smaller and smaller to form the soil. So, this is the part in which the parents of top soil and sub soil live. Ahaa! These are big rocks. These big rocks are kind of grandparents of the soil. They break down and form the parent material. Then the parents rocks break down due to the pressure, temperature and water. This is how the sub soil and top soil are formed. Please uproot a plant. I want to show you something. Ah look! It's an earthworm. Don't worry, they aren't harmful. Earthworms are friends of the soil and plants. Okay. Now, we have to study in a classroom. So, now you know why top soil is important for us, as it is the only place where we can grow food for ourselves and other animals. See what a small portion of the earth we have for growing food! Did you know that it takes 500 to a 1000 years to get one inch of top soil? Yes, nature takes many years to make even an inch of top soil. But, did you know that even this tiny part is in danger? Yes, this part is getting smaller and smaller due to soil erosion. Oh, you didn't know about soil erosion? It is about our top soil getting washed or blown away by water, and wind. We humans are also responsible for it. We're making new houses and roads all the time. So, the area for plant life is becoming smaller and smaller. You're right. The area for plant life is becoming increasingly smaller. Did you know that plants help in stopping soil erosion? Look at this. On one side, there are plants. On the other side, it is plain land. When rain comes, plants hold the soil. So, it is not eroded on the left hand side. On the right hand side, there are no plants or trees. So, the land is getting eroded. So, we see plants are very important in preventing soil erosion. So, you see, plants are very important that not only gives us food, clothes, and many other things, but, they also save our soil from being eroded. We humans are cutting down trees without planting new ones. We're putting more animals to graze in small areas. So, the protective layer of the earth is decreasing. Let's go to the laboratory and see an experiment on how plants help in decreasing soil erosion. So, let's put water in both of these. So, we saw today plants and trees are very important for us. If we don't save them, then more soil erosion will occur. And, the area for plant growth will become smaller and smaller. I hope everybody understands that we need to plant more trees, and should avoid cutting them down. Otherwise, there won't be any soil left for growing food. Here's an interesting question for you. Did you know that natural erosion is good for the earth? Ha, ha! Confused! Check out the video on weathering and erosion on www.makemegenius.com to understand how erosion shapes our world.

Video Details

Duration: 6 minutes and 43 seconds
Country:
Language: English
License: Dotsub - Standard License
Genre: None
Views: 11
Posted by: pgtranscribes on Apr 4, 2015

Interaction-2_Video-2

Caption and Translate

    Sign In/Register for Dotsub to translate this video.