Energy Flow in Ecosystems Chapter 3-3 Energy Flow in Ecosystems

Daily Objectives Trace the flow of energy through living systems. Identify the three types of ecological pyramids

Trophic Levels Each link in a food chain is known as a trophic level. Trophic levels represent a feeding step in the transfer of energy and matter in an ecosystem.

Trophic Levels Biomass - The amount of organic matter comprising a group of organisms in a habitat. As you move up a food chain, both available energy and biomass decrease. Energy is transferred upwards but is diminished (reduced) with each transfer.

Trophic Levels Primary Consumers (Herbivores) Producers (Autotrophs) E Secondary Consumers (Small Carnivores) Primary Consumers (Herbivores) Producers (Autotrophs) E N R G Y Tertiary Consumers – Top Carnivores 0.1% 1% 10% 100%

Ecological Pyramids Show the relative amount of energy or matter contained within each trophic level in a given food chain or food web.

Energy Pyramid Show the relative amount of energy available at each trophic level of a food chain or food web. On average, about 10 percent of the energy available within one trophic level is transferred up to the next trophic level.

Biomass Pyramid A pyramid of biomass illustrates the relative amount (mass) of living organic matter available at each trophic level in an ecosystem.

Numbers Pyramid A pyramid of numbers shows the relative number of individual organisms at each trophic level in an ecosystem.

Food Chain A simple model that shows how matter and energy move through an ecosystem.

Food Web Shows all possible feeding relationships in a community at each trophic level. Represents a network of interconnected food chains. Food webs are complex, so it is often difficult to predict exactly how they will respond to environmental changes.

Food Web

Food Chain Food Web - Just 1 Path of Energy - All Possible Energy Paths