Ecosystem Dynamics Energy and Nutrients in the Ecosystem

Energy Energy…….. The ability to do work Builds cells and tissues Growth Reproduction Responding to environment

Energy Energy is passed from organism to organism by feeding relationships in the ecosystem!!! Trophic Levels (feeding levels) Each step in the transfer of energy in a community Producers Consumers Decomposers

Producers Producers/Autotrophs: can make their own food Use photosynthesis to convert sunlight in to chemical energy Produce carbohydrates for immediate use or storage for later Examples include plants, algae, and some bacteria

Consumers Consumers/Heterotrophs: (obtain food by eating other organisms) Ex: Animals, fungi, protists, and most bacteria Types of Consumers: Primary Consumers Secondary Consumers Tertiary Consumers

The Flow of Energy Energy flows through an ecosystem. From the sun to producers to consumers to decomposers, energy powers the interactions of ecosystems.

Food Chains Shows the flow of energy from one organism to another through each trophic level Energy flow is represented by an arrow Arrow goes in direction of energy

Food Web A food web is a representation of all of the interconnected food chains in an ecosystem Food webs show multiple feeding relationships

Ecological Pyramids Ecologists use ecological pyramids to represent the relationships among trophic levels There are 3 types of ecological pyramids: Pyramid of Energy Pyramid of Biomass Pyramid of Numbers

Shows total amount of incoming energy at each trophic level Pyramid of Energy Shows total amount of incoming energy at each trophic level The 10% rule predicts that only 10% of the energy in one trophic level is available to the next level

Shows total mass of living tissue at each level Pyramid of Biomass Shows total mass of living tissue at each level

Pyramid of Numbers Shows the total number of organisms at each trophic level

Organization Species organisms that interbreed and produce fertile offspring Population A group of the same species living in an area Community different populations interacting in an area Ecosystem Community interacting with its environment