Intro Quiz: Interdependence in the tropical rainforest

Video: Interdependence in the tropical rainforest

﻿Hello everybody, this is Mrs. Patterson. Welcome to lesson two, interdependence in the rain forest. This is part of the unit six tropical rainforests. We're going to be looking at interdependence, that really important key word. We're going to be looking at the nutrient cycle, we're going to be completing some exam questions. You are going to need a pencil, a pen and something to write on, if you need to go and get those please go and get those now, and I will see you in a few minutes. Okay, so interdependence in the rainforest. So all the parts of the tropical rainforest are linked. And so, if one part changes in the tropical rainforest, so does another part. Whether that is a negative change, or whether that is a positive change, there will be some sort of change. This is particularly the case in tropical rainforests because the biodiversity is so high. So biodiversity is our first key word of the day. So biodiversity is the variety of plants and animals living in a particular area. It's suggested that over 50% of the world's plants and animals live in tropical rainforests. The second key word of the lesson today is interdependence. So interdependence, is the way that all parts of the rainforests such as the climate, the water, the soils, the plants, animals, and humans are all dependent on each other. If you need to pause the video here, to write those key words down, then please do so and start the video again once you finished. So a typical food chain that we would find in the tropical rainforest, is on the diagram that you can see on the screen now. So a typical food chain shows how energy passes, through an ecosystem. So we have producers, primary consumers, secondary consumers and tertiary consumers. So if we look at our typical food chain of the rainforests we would see, that the leaf is the producer. So, the food chain always starts with a producer and the producers are usually green plants, which make their own energy via photosynthesis. So the leaf in this instance is our producer. The caterpillar is the primary consumer. They are the first animal to eat the leaf, okay! And they normally only eat green plants. Then we have our chameleon. Now the chameleon is the secondary consumer, and which is an animal that will eat the primary consumers so the chameleon will eat the caterpillar. Then we have the snake which is our tertiary consumer. Okay, so the snake will eat the chameleon, and they will gain their energy from eating the chameleon, and the chameleon will gain their energy from eating the caterpillar and so on. The last part of this food chain is the mongoose. So the mongoose will eat the snake, the snake will eat the chameleon, the chameleon we eat the caterpillar and the caterpillar will eats the leaf. Okay, it's a nice food chain, a very simple one. Therefore, there are only certain animals at certain levels. We are going to move on to have a look at food webs, and how they've become quite complex, with multiple food chains within them. So here is a food web for the tropical rainforest as you can see that there are lots of different layers here. So we've still got our producers, our primary consumers, secondary and tertiary, but this time around, rather than it just being one producer, there are five producers. Okay, so at the bottom at the producers, we've got orchids, we've got a variation of seeds. We've got banana trees, bamboo trees and coconut trees. So all of these gain their energy directly, from photosynthesis. Then we've got a layer of primary consumers. So the primary consumers can eat any number of those producers so they don't just necessarily stick to one producer. So if we take for instance, the monkey, so the monkeys they eat the banana trees, they also eat from the bamboo trees. Okay, so they've got two producers that they eat from. The secondary consumers you can see they slightly get larger in size not always but most of the time. So here we've got, if we take this nice chain here we've got the coconut tree, that's the producer. The grasshoppers are the primary consumer, and then the frogs eat the grasshopper, as a secondary consumer. And then the jaguar eats the frogs, as a tertiary consumer. That's a nice food chain. But we can see that also the iguanas like to eat the grasshoppers and also the vampire bats also like to eat the grasshoppers. So therefore there are three different animals there, fighting for the grasshoppers in terms of this food chain. Okay, so what I would like to do, is I would like you to answer these three questions, using the food web diagram that's on your screen now. So question number one, is describe what would happen, if the orchids disappeared? Which is worth 2 marks. Question two explain the impact of the grasshopper population if it grew. That's worth 3 marks and question number three, explain the impact of the food web if the fruit bats went extinct. Now the fruit bats are a primary consumer, so you need to have a look to see what the chain reaction would be on other animals or producers around the fruit bat. Now in terms of question number two and three, I do have a model answer that you might want to have a look at, and use as a model answer, in terms of helping you with question two and three. So I've chosen explain the impact of the Macaw population growing. So I've slightly changed the question, but the same principle does apply and it's worth 3 marks. So I've said if there was more Macaws, then potentially there would be a decrease in orchids and banana trees. That would be worth 1 mark. This could mean that there would be more bamboo trees, in the area, that's worth another mark. Further up the food web, it could mean that there was more jaguars in the area, worth another mark. So I'm thinking about what the chain reaction, on other producers, primary consumers, secondary consumers would be. Okay, so going back to the task page. You've got three questions there. Now these three questions should take you about 10 minutes, to answer in total, so pause the video here. Okay, so this diagram shows about interdependence in the rain forest. So this is how the soils, the climate, the plants, the animals, they all rely on each other in the ecosystem. Although at the same time they are all in competition with each other. So have a look at this diagram. So we've got rainfall, we've got the sun, we've got energy, and therefore we've got all the different parts of an ecosystem. So we've got decomposers, we've got scavengers, we've got the nutrient cycle from the soils, we've got the different layers of the rainforest, all working together in order to produce, this very unique ecosystem that is a tropical rainforest. So we're going to have a look at a little bit more detail about, we're going to look at the nutrient cycle, we're going to look at how soils actually form part of the ecosystem, and how so many things are quite reliant. So this diagram is of the nutrient cycle. So we can see that we have got in bold letters, we've got soil and we've got litter, and then we've got a big brown circle with an X in the middle. Okay, now this X is called biomass. So we've got three things here going on. We've got soil, we've got litter, and we've got biomass. Okay, and I'm going to talk about that in a bit more detail in a minute. So this nutrient cycle is about the forest floor. Okay, we know about the forest floor, it's got an abundance of insects. And it means that the soil is able to rapidly break down, or the decomposers are able to rapidly break down any dead leaves and plant material. From these decomposes, they produce produce nutrients that are easily absorbed by the plant roots. And because there is an abundance of rainforest vegetation, the nutrients are taken up really quickly. So changes in one part could have devastating effects on this nutrient cycle. For example, that the loss of tree cover due to a fire, for instance, would affect the nutrient cycle and it would cause all soil erosion and would cause wash off from the precipitation. This then increases the loss of nutrients, via the soil because of leaching and extra flooding that can happen in the area. So in all nutrient cycles, there's interactions between the atmosphere and the soil and the food chains that are involved. Nutrient cycles, vary greatly between each different ecosystem. As I've said that the nutrient transfer is dependent on the amount of moisture and heat and vegetation and the length of the growing season. The litter that we can see on the diagram, is about the surface layer of vegetation, which over time breaks down to become humus. The biomass is the total amount of mass or living organisms that are in the area. In each of the diagrams that we've just seen, the nutrient transfer is shown, by the width of the arrows. So can we see those blue arrows? Okay, so in our circles, we've got nutrient stores and the arrows show us nutrient transfer. So whether it's a transfer from litter or to biomass, then they are showing us the transfer. So the thicker the blue line, the more transfer or nutrient transfer is happening. As I've already said that there is an extremely rapid process of nutrient transfer, because of the high temperatures, the rainfall and the humidity in the tropical rainforest. Biomass is the largest store of nutrients, due to the vast array of plants found in the tropical rainforest. Few nutrients are in the litter, due to their rapid decomposition. So I've got a label on there also saying why. Okay, so we've just gone through X, which is the biomass store. So Y we now know is a nutrient transfer. Okay, so this is the nutrient transfer, from litter to the soil. So what I would like you to do, is I would like you to draw this diagram with the labels, and answer the question below. So I'd like you to draw the nutrient cycle. So I'd like you to draw it just as it is. So make sure that you've got different size arrows, on your diagram. Make sure that you label X as biomass and Y as nutrient transfer. And then I want you to answer question number two, describe how nutrients are cycled in the rainforest. And that's worth 3 marks. There are three different stores, so we can see the soil, the biomass and the litter. Okay, and we can see we can see multiple arrows, so you could talk about, any number of those in your answer. Pause the video here. This should probably take you around, 10 minutes to complete. Welcome back okay, so let's go through what a model sentence might look like for question number two, describe how nutrients are cycled in the rain forest. So, my first sentence would be regarding the soil and the transfer of nutrients to the biomass. So, we can see that the arrow is quite large quite thick in size. And therefore I would say something along the lines of, that nutrients are transferred from the soil rapidly to the biomass such as trees, in the rainforest, due to the fact that there is so many plants in the rainforest or so many trees in the rainforest. That would be my first sentence. That would get you one mark. You then need to mention how the nutrient transfers, from the biomass to the litter. So as we can see that those arrows, are fairly thin in size, and therefore there's not a lot of nutrient transfer from the biomass to the litter. You then needed to say something from the litter to the soil, and we can see that there's a large Y arrow, okay, that nutrient transfer from the decaying matter back to the soil, and a lot of nutrients is then given back to the soil. So all of those things as separate sentences, would get you 3 marks. Looking at another diagram on interdependence, and as already said throughout this lesson, all of these elements on this diagram or on this cycle, are connected and they rely on each other. So the climate relies on the plants and animals. The animals rely on the soils, the soils rely on the climate, and also the layers of the rainforest, you know, the plants rely on them depending on which layer that they live in. All of them are interconnected and all of them are interdependent on each other. What I would like you to do as the main task for today is using this diagram on interdependence, I want you to attempt this 4 Mark question. So this 4 mark question is asking you to explain how tropical rain forests are a good example of an interdependent ecosystem. It's worth 4 marks, you have got four parts of the interdependent cycle, and therefore each one, does need to be discussed and explained in your answer. Here's a model answer of how tropical rainforests are a good example of an interdependent ecosystem. So I've said an example of interdependence in the tropical rainforest, is the plants that are dependent on the water in order to support growth, therefore they're closely linked to the climate. That would be worth 1 mark. The animals are linked to the plants for the food chains or complex food webs, that's another mark. And the layers of the tropical rainforest are linked to the climate, as different types of plants require, differing amounts of sunlight, that's worth another mark. This is also linked to the animals for food and shelter. And the soil is linked to the vegetation and the nutrient cycle. This is also linked to the climate to allow nutrients of the nutrient cycle for the times lap to be quickened. That's worth 1 mark as well. So you can say a variety of things, but that's just the model answer that I've gone for. So I've mentioned all different parts of the interdependence cycle. And I've said how that they something is connected to something else. That's important. So going back to the main task of today, I need you to write down that question, make sure that you use connectors such as, this means that, or which means, this leads to, in your answer just to make sure that you're really explaining the links, between those different parts of that cycle. This answer should probably take you around six minutes, to complete. Pause the video now and complete your task. So that does bring us to the end of lesson two today interdependence in the rain forest. Today, we looked at a simple food chain, and then we looked at a complex food web, of the tropical rainforest. We then moved on to have a look at the nutrient cycle and started to understand the nutrient stores and the nutrient transfers in the tropical rainforest. And how all of that is quickened because of the climate, that a tropical rainforest finds itself in. We've then linked that back to an interdependent cycle, and that you've answered some exam style questions on that. Next lesson we're going to be looking at more detail about plant adaptations and how they have changed over time in order to survive. If you would like to share your work, please ask your parent or carer to share your work on Instagram or Facebook or Twitter by tagging @OakNational and #LearnwithOak. And hopefully I'll see you next lesson. Bye.

Exit Quiz: Interdependence in the tropical rainforest

Completed: Interdependence in the tropical rainforest

In this lesson we will be learning how the animals and plants rely completely on each other to survive.  This is called 'interdependence'.

Geography

Interdependence in the tropical rainforest

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