3. The Compenents of the Natural Environment

# 3. The Compenents of the Natural Environment ## TU 7. Lesson 4: The notion of the environment (Definition of natural environment; Components; Ecosystem) ### Introduction Welcome to Lesson 4! Today, we will explore the exciting world around us. We'll learn about what makes up our natural environment, understand its different parts, and discover how everything works together in an ecosystem. Understanding these concepts is key to appreciating our planet and how we can protect it. ### Key Concepts #### 1. Definition of Natural Environment The **natural environment** refers to everything around us that is created by nature, not by humans. It includes all living and non-living things that occur naturally on Earth. Think of it as the world's original design, before people started building cities and roads. #### 2. Components of the Natural Environment The Earth's natural environment is made up of four main components, often called 'spheres', which constantly interact with each other: ##### a. Lithosphere * The **lithosphere** is the solid, outermost layer of the Earth. It includes: * **Crust:** The very thin outer skin of the Earth. * **Upper part of the Mantle:** The layer beneath the crust. * It's where we find all the landforms like mountains, valleys, plains, and also the soil and rocks. It's the ground we walk on! ##### b. Hydrosphere * The **hydrosphere** includes all the water on Earth, whether it's liquid, solid (ice), or gas (water vapor). * Examples: * Oceans, seas, rivers, lakes, ponds * Underground water (groundwater) * Glaciers and ice caps * Water vapor in the atmosphere * Water is essential for all life on Earth. ##### c. Atmosphere * The **atmosphere** is the blanket of gases that surrounds the Earth. * It is vital because it: * Contains the air we breathe (oxygen, nitrogen, etc.). * Protects us from harmful radiation from the sun. * Helps regulate Earth's temperature, keeping it warm enough for life. * Is where all weather phenomena (rain, wind, clouds) occur. ##### d. Biosphere * The **biosphere** is the part of Earth where life exists. It includes all living organisms, from the smallest bacteria to the largest trees and animals. * It overlaps with parts of the lithosphere, hydrosphere, and atmosphere. * The biosphere depends on the other three spheres to provide the necessary conditions for life (land, water, and air). #### 3. Ecosystem An **ecosystem** is a community of living organisms (plants, animals, microorganisms) interacting with each other and with their non-living environment (like air, water, soil, sunlight). ##### a. Components of an Ecosystem * **Biotic Components:** These are all the living parts of an ecosystem. * *Examples:* Plants, animals, fungi, bacteria. * **Abiotic Components:** These are all the non-living physical and chemical parts of an ecosystem. * *Examples:* Sunlight, water, air, soil, rocks, temperature, nutrients. ##### b. How Ecosystems Work In an ecosystem, living things depend on each other and on the non-living environment for survival. For example, plants use sunlight (abiotic) and water (abiotic) to grow, animals eat plants, and when animals die, their bodies decompose and return nutrients to the soil (abiotic), which then helps new plants grow. This shows the continuous flow of energy and nutrients. ### Vocabulary * **Natural Environment:** All living and non-living things that occur naturally on Earth. * **Lithosphere:** The solid outer layer of the Earth, including land, rocks, and soil. * **Hydrosphere:** All the water on Earth (oceans, rivers, lakes, ice, water vapor). * **Atmosphere:** The layer of gases surrounding the Earth (air, weather). * **Biosphere:** The part of Earth where all life exists. * **Ecosystem:** A community of living organisms interacting with their non-living environment. * **Biotic Components:** The living parts of an ecosystem (e.g., plants, animals). * **Abiotic Components:** The non-living parts of an ecosystem (e.g., water, air, sunlight, soil). ### Examples 1. **A Forest Ecosystem:** * **Lithosphere:** The soil, rocks, and land on which trees grow. * **Hydrosphere:** Rainwater, streams flowing through the forest. * **Atmosphere:** The air within the forest, oxygen produced by trees. * **Biosphere:** Trees, birds, insects, animals like deer living in the forest. * All these components interact: trees get water from the hydrosphere and nutrients from the lithosphere, breathe gases from the atmosphere, and provide shelter for animals (biosphere). 2. **A Pond Ecosystem:** * **Biotic:** Fish, frogs, water lilies, algae, insects. * **Abiotic:** Water, sunlight, oxygen dissolved in water, temperature, rocks at the bottom. * The fish breathe oxygen (abiotic) from the water (abiotic), eat algae (biotic), and their waste provides nutrients for plants (biotic). ### Exercises 1. Which of the following is NOT a component of the natural environment? a) Atmosphere b) Building c) Hydrosphere d) Biosphere 2. Fill in the blanks: a) The layer of gases surrounding the Earth is called the __________. b) All water on Earth is part of the __________. c) All living things on Earth make up the __________. d) The solid part of the Earth, including rocks and soil, is the __________. 3. Give two examples of biotic components in an ecosystem. 4. Give two examples of abiotic components in an ecosystem. ### Assignment 1. Draw a diagram showing the four components of the natural environment and label each one. You can use different colours to represent each sphere. 2. Choose a local area (like your school garden, a park, or a nearby river). Identify and list at least three biotic components and three abiotic components that you can observe in that area. Explain how one biotic component might depend on an abiotic component. ### Summary Today, we learned that the **natural environment** includes everything around us created by nature. It is made up of four interacting parts: the **lithosphere** (land), **hydrosphere** (water), **atmosphere** (air), and **biosphere** (all living things). We also discovered what an **ecosystem** is – a community of living (**biotic**) and non-living (**abiotic**) components interacting with each other to form a functioning whole. Understanding these basics helps us appreciate the complexity and interconnectedness of our planet.