Energy Flows thru Ecosystems LIVING THINGS CAPTURE & RELEASE ENERGY MODELS HELP EXPLAIN FEEDING RELATIONSHIPS AVAILABLE ENERGY DECREASES AS IT MOVES THROUGH AN ECOSYSTEM.

Living Things Capture & Release Energy Everything you do requires energy. You use chemical energy (in food) which is released to environment as heat, as you sweat. All living things need energy. Most comes from Sun originally. First, living things must capture Sun’s energy and store it in a usable form (food). Producers, Consumers and Decomposers all need energy and transfer it in some way.

PRODUCERS Producer: organism that captures energy & stores it in food as chemical energy. Producers package energy for other living parts of an ecosystem. Most energy enters thru photosynthesis (CO 2 + H 2 O  sugar +O 2 ) Plants are most common producers on land, photosynthetic bacteria & algae help make food in water. Chemosynthesis: produce food from chemicals (special bacteria in deep ocean water volcanic vents)

CONSUMERS Consumer: can’t produce own food, must get it by eating/consuming other organisms. Primary consumer (caterpillar) are first link between producers & other consumers; Secondary consumer (bird) eat primaries; tertiary (cat) eats secondaries. Scavengers are special consumers (like vulture, that feeds on dead animals)

DECOMPOSERS Decomposer: break down dead plant & animal matter into simpler compounds. A type of clean-up crew of an ecosystem. Fungi & bacteria break down dead leaves, roots, branches, & dead animals into soil again. A pinch of soil may have ½ million fungi & billions of bacteria. Decomposers release the last bit of energy from once- living matter back into to environment & recycle matter at the same time.

HELPFUL FOOD MODELS FOOD CHAIN: Feeding relationship between a producer & single chain of consumers in ecosystem. 1 o Cattail  2 o caterpilla r  3 o frog  4 o heron Energy is captured & released at each link in the chain. Arrows show flow of energy from organism to organism. FOOD WEB: Feeding relationship between many different consumers & producers in an ecosystem. A web can show how one consumer can play several roles in an ecosystem. If one organism is removed from chain or web, it may affect many other organisms in the ecosystem.

Energy Decreases as Moves Thru Ecosystem Energy Pyramid = shows amount of energy available at each feeding level of an ecosystem. First level = producers, 2 nd level are primary consumers and so on. Usable energy decreases as it moves from producer to consumers (gets smaller, the farther up the pyramid you go). Plants capture Sun’s Energy  insects eat plant & use some energy  shrew eats insect & uses some  owl eats shrew