Ecology Ecology The study of interactions among between

Ecology

Ecology The study of interactions among & between organisms and their environment.

Levels of Ecology • Species: group of organisms that can produce fertile offspring. • Populations: group of the same species • Communities: group of different populations • Ecosystem: all of the organisms living in a particular place & their nonliving environment • Biome: group of ecosystems with the similar climate and communities • Biosphere: portions of the planet where life exists.

Energy Flow: Producers • Sunlight is the main energy source • Autotrophs: use energy from the environment to assemble simple inorganic compounds into complex organic molecules. – Photosynthesis - use light energy • CO 2 + H 2 O O 2 + sugars – Chemosynthesis - use chemical energy to produce carbohydrates • volcanic vents on the deep ocean floor, hot springs in Yellow Stone park

Energy Flow: Consumers • Heterotrophs: rely on other organisms for their energy and food supply • Herbivores: only plants; cows, caterpillars, deer • Carnivores: eat animals; snakes, owls, cats • Omnivores: both plants and animals; humans, bears, crows • Detritivores: plant and animal remains and other dead matter; mites, earthworms, snails, and crabs • Decomposers: breaks down organic matter; bacteria and fungi

Feeding Relationships • Energy flows one direction in an ecosystem sun/inorganic compound (autotroph)producers (heterotroph) consumers • Food Chain: steps in which organisms transfer energy by eating or being eat • Grass antelope coyote

Food Web • complex relationship in an ecosystem that links all food chains together • Trophic Level – each step in a food chain – Producers – first level – Consumers – second, third, or higher level • Each consumer depends on the level below for energy

Food Web

Ecological Pyramids • shows the energy/matter in each trophic level • Energy Pyramid: ~10% of the energy in each tropic level is transferred to the next level • Most is used for life processes; respiration, reproduction, movement, & some is released as heat

Biomass Pyramid • Biomass: amount of living tissue within a given tropic level (g organic matter/area) • Biomass Pyramid: amount of potential food available for each trophic level

Pyramid of Numbers • number of individual organism at each trophic level • Exception: forest: a single tree has many organisms, insects, that live in/on it and there are fewer producers than consumers in a forest