Transcript Energy Flow
Energy Flow How does energy move through the ecosystem? http://www.armofthesea.info/images/landscapes/crommet_lg.jpg How does Energy Flow through Ecosystems? All organisms Hence for all require This energy is organisms there energy for life used must be:or lost processes. and is not available A source of if consumed energy What do you Growth Locomotion mean by life A loss of usable processes? energy Reproduction Conservation: • Law of Conservation of Matter –Matter cannot be created nor destroyed, only transformed from one form to another. First Law of Thermodynamics also called… • Law of Conservation of Energy – Energy can be converted from one form or another but cannot be created nor destroyed, only transformed from one form to another. How does energy flow through a food chain? • Food Chain: A simple diagram of one string of feeding relationships in an ecosystem, showing the direction of the transfer of energy in that system. Sun Grass Rabbit Soil Wolf Bacteria Energy: • 2nd Law of Thermodynamics: –When energy is changed from one form to another, some energy will be lost to the larger environment. • Nothing is ever 100% efficient. • This is due to entropy (nature’s tendency towards randomness). 2nd law of thermodynamics in action: When energy is changed from one form to another, some energy will be lost Why? Rabbit moves, respires, grows, etc.. Energy is used, no longer available if eaten. Sun Grass Rabbit Soil Wolf Bacteria What are the parts of a food chain? Producers • Organisms that make their own food from inorganic molecules and energy. – eg. Plants, blue-green algae Energy through is –Inorganic Most accomplish energy building almost always Molecules = photosynthesis from the sun molecules that are (very rare not part of a living exceptions) organism Water + Carbon Dioxide + Sunlight Sugar + Oxygen Consumers • Organisms that cannot make own food. Consumers are: all animals, fungi and most bacteria They must obtain energy by eating other organisms — through a process called cellular respiration Sugar + Oxygen Carbon Dioxide + Water + ATP (energy) Decomposers • Bacteria and fungi that break down organic material Decomposers are essential to ecosystem health because they recycle nutrients back for producers to reuse. What is a Food Web? • a group of food chains showing all of the feeding relationships in an ecosystem. Food Web Sun Human Wolf Sheep Rabbit Grass MiceDeer Flower Fox Bacteria Carrots Nutrient Rich Soil Biological Magnification • Increasing concentration of a substance in the tissues of organisms in the higher levels in a food chain or web. (Nearly always something dangerous, like a toxin) Many toxins in the water Many toxins in the person • Biological Magnificationaccumulation of increasing amounts of toxin within tissues of organisms. Video on Biological Magnification Trophic Levels • Trophic level — a layer in the feeding relationship of an ecosystem, one link in the food chain/web. • Biomass — total amount of organic material present in a trophic level. So, all producers are at the same trophic level and all primary consumers are at the next trophic level. Organic = is currently living or lived in the past Energy Pyramids http://www.vtaide.com/png/foodchains.htm http://www.earthforce.org/files/1284_image2_Energy_Pyramid_for_ Galvbay.jpg • Another way to look at trophic levels. • a diagram showing the relative amounts of energy/biomass in the different trophic levels. • Lowest trophic levels are at the bottom: Producers have the greatest biomass. Example of an Energy Pyramid 1 pound MAN MAN 0.1% 10% 100 % of the sun’s energy FOX 1% 10% 10% RABBIT Rabbit 90% Energy Lost during conversion to heat, waste…. 90% 10 pounds FOXES 100 pounds RABBITS 10% Grass 90% 1000 pounds of GRASS - The decreasing size of the pyramid shows that each level of the pyramid has a smaller and smaller number of those organisms.