Summary of Introduction to Environmental Science

## Introduction The environment is the surrounding space in which people, animals, birds and plants live and develop. Human activities and population growth affect the environment in many ways. Pollution is one of the main threats to the health of the environment and all living things. > **Definition:** Pollution is damage to the air, sea, rivers or land caused by chemicals, waste and harmful gases. ## Types of Pollution Break the topic into main categories to understand how pollution affects different parts of the environment. ### Water Pollution > **Definition:** Water pollution occurs when waste poisons rivers, lakes, seas or groundwater. - Sources: industrial waste, sewage, agricultural runoff (pesticides, fertilizers), oil spills, litter. - Effects: harms fish and other aquatic life, contaminates drinking water, spreads disease. - Practical example: dumping used motor oil into a stream can poison fish and make the water unsafe for humans. ### Land (Soil) Pollution > **Definition:** Land pollution happens when waste materials and chemicals poison the ground and may leak into underground water. - Sources: toxic waste, improper disposal of chemicals, excessive use of pesticides and fertilizers, illegal dumping. - Effects: reduces soil fertility, contaminates crops, harms organisms living in soil. - Practical example: long-term use of chemical pesticides can leave residues in farmland, reducing crop yield and food safety. ### Air Pollution > **Definition:** Air pollution occurs when exhaust fumes and harmful gases contaminate the air we breathe. - Sources: vehicle exhaust, industrial emissions, burning fossil fuels, open fires. - Effects: respiratory illnesses in people, damage to plants, contribution to climate change. - Practical example: car congestion in cities increases smog and respiratory problems for residents. ## Major Environmental Problems and Disasters These problems are often connected to pollution or the ways humans change the environment. - Earthquakes – natural but impact is worsened when infrastructure is weakened by poor planning - Floods – worsened by clogged drains and deforestation - Hurricanes – stronger with higher ocean temperatures - Droughts – worsened by water pollution and mismanagement - Volcanic eruptions – natural, but ash and gases contribute to air pollution - Tsunami (tidal waves) – natural sudden floods - Deforestation – removal of trees reduces biodiversity and increases erosion - Starvation (famine) – can result from contaminated water and damaged crops - Ozone layer depletion – increases harmful UV radiation - Greenhouse effect – leads to global warming and climate change Did you know that reducing greenhouse gas emissions helps slow down global warming and can reduce the frequency of extreme weather events? ## The 3Rs: Reduce, Reuse, Recycle > **Definition:** The 3Rs are three basic actions everyone can use to lower the amount of waste and pollution. - **Reduce**: Use fewer disposable items and generate less solid waste (domestic waste). Practical example: buy food in bulk to avoid extra packaging. - **Reuse**: Use items multiple times or buy second-hand goods. Practical example: reuse glass jars for storage or shop at thrift stores. - **Recycle**: Process materials such as paper, glass and some plastics so they can be made into new products. Practical example: put paper and glass into separate recycling bins. | Action | What it means | Example | |---|---:|---| | Reduce | Create less waste | Buy larger-size items, avoid single-use plastics | | Reuse | Use many times | Refill water bottles, donate clothes | | Recycle | Turn waste into new materials | Recycle paper, glass, some plastics | ## What an Individual Can Do Small daily choices add up. Here are practical, specific actions. Do: - Turn off electrical equipment when not in use to save electricity - Use public transport: trains, buses, bicycles instead of cars - Separate waste: use different bins for glass, paper, plas