The Great Outdoors - PDF

Term 1: “The Great Outdoors” Know 1. Acid Rain - Pure water: pH 7 - Normal rain: pH 6 - Acid rain: pH 5 - Normal rain picks up carbon dioxide while coming down, making it slightly acidic (Carbonic acid) - Acid rain comes from pollutants - Sulfur dioxide and n...

Term 1: “The Great Outdoors” Know 1. Acid Rain - Pure water: pH 7 - Normal rain: pH 6 - Acid rain: pH 5 - Normal rain picks up carbon dioxide while coming down, making it slightly acidic (Carbonic acid) - Acid rain comes from pollutants - Sulfur dioxide and nitrous oxides from cities dissolve in clouds which move and rain over landscapes and affects the landscape - Eg. Coal power station where pollutants come out of the chimney which release gases that dissolve in water such as sulfur dioxide and sulfur trioxide (sulfuric acid) - Eg. Exhaust fumes from cars release nitrogen (nitric acid) which also makes rain acidic - Effects of Acid Rain - Rivers and lakes | Become acidified leading to the death of aquatic organisms - Soils | Become acidified and prevents plants, trees and crops from growing - Trees | Wears away the protective coating on leaves and prevents them from photosynthesising properly - Buildings made of limestone| Get corroded away/damaged from the acid reacting with the calcium carbonate - Metal objects | React with acid and corrode metal objects - Acids: Found in rainwater (carbonic acid from CO₂), in soil (humic acids), and in decaying organic matter. - Bases: Found in limestone (calcium carbonate), oceans (alkaline seawater), and in some cleaning products 2. Behaviours of Light - Absorption: Absorbs wavelengths to show colour - Seeing colour - All the wavelengths of visible light except red which is reflected, is absorbed to see red - White light contains all the wavelengths are reflected - Black light means all the wavelengths have been absorbed - Reflection: When a light ray hits a surface and reflects off - Light travels in straight lines but can be reflected off different surfaces - Always reflects at the same angle as the incident ray - The surface of a pool getting hit by light and reflecting - Refraction: The bending of light or changing direction of light between one medium and another of varying density - When light passes from air to water, the light is bent due to the difference in the water’s density compared to air, so when there is a straw in the water it will appear bent 3. Conduction & Convection - Conduction: Transferring heat through physical contact - Convection: Transferring heat through liquid 4. Ecosystem - An area with living organisms such as plants and animals and non-living parts of the environment 5. Biotic and Abiotic factors - Biotic: Living things - Food - Predators - Disease - Competition - Plants - Abiotic: Non-living things - Climate factors Temperature Rainfall Humidity Wind intensity/direction Sunlight - Chemical and Physical factors Oxygen Carbon dioxide Other gases pH of water - Edaphic factors (relating to soil) Soil type (formed from rocks Soil pH Soil compaction - Fire  6. Carbon/oxygen/nitrogen cycle in an ecosystem - Carbon Plants absorb carbon dioxide during photosynthesis and release it when they decay - Oxygen During photosynthesis, oxygen is released into the atmosphere which humans and animals breath Breath in oxygen, breathe out carbon dioxide linking back to the plants which absorb it for photosynthesis - Nitrogen Plants take nitrogen compounds in their roots Animals receive the compounds when they eat the plants When the animals die or excrete waste, the compounds re-enter the soil Gets broken down by decomposers 7. Cellular respiration - The process where cells chemical reactions break down glucose to produce ATP which is used as energy to power the body - C6H12O6 + 6 O2 → 6 CO2+ 6 H2O - Carbohydrate + Oxygen → Carbon dioxide + water 8. Sustainable ecosystems - A sustainable ecosystem means that it can support itself without needing of outside assistance Understand 1. Movement of particles by conduction & convection - Conduction: The transfer of heat energy in solids - Particles in solids that are close vibrate more when they heat up - When they vibrate, heat is passed through from one end of the solid to the other - Metals are the best conductors of heat as they have electrons that are free and move further and faster - Convection: The transfer of heat energy in liquids ad gases - Particles near the heat source gain energy and move further apart - The liquid/gas becomes less dense and rises creating a convection current 2. Absorption & Reflection of light to see colours - The wavelengths that are visible all are a colour and when something is red, all the other wavelengths are absorbed except for the red wavelength which gets reflected, showing the colour red - When white is shown it means all the wavelengths are reflected - When black is shown it means all the wavelengths are absorbed 3. Energy in a Food Chain/Web - Food Chains: Food chains show which organisms eat other organisms - Eg. Grass → Rabbit → Fox - The arrow can show eaten by but mainly shows how energy flows from one organism to the next - Producers (green plants, can photosynthesise), Primary Consumers (Herbivores), Second Consumers (Carnivores) and Tertiary Consumers (Carnivore, Top Carnivore) - Each level of a food chain is known as a trophic level - Detritivores eat dead and decaying matter, breaking it up into smaller particles (worms, beetles) - Decomposers also eat dead and decaying matter but break them into nutrients that can be recycled and taken by the plants (bacteria, fungi) - Detritivores and Decomposers can eat each other when they die - Energy is formed by sunlight which is captured by the producer and then flows through the food chain but loses energy through the form of heat - Food Web: Complex food chain that overlaps - - Omnivore (Feeds on plants and animals) - The more complex the food web, the more stable of population of organisms 4. Role of Respiration - Plays an important role in carbon output which is key for photosynthesis 5. Strategies to conserve ecosystems - Mangrove Swamp Management: - No overfishing / hunting - Minimal removal - Encourages mangrove growth while supporting animals in the swamp and clean the river system while protectin the coastline - Land Management: - Low temperature burning - Small patches called mosaic pattern - Burnt at right time in season when it is easily managed - Allows the growth of native plants and allows native animals to thrive