Rangeland Ecology

Hierarchy of Ecological Levels

Figure from: www.goldiesroom.orgOn-line biology class

Basic Energy Flow

Producers Plants

DecomposersFungi & Bacteria

ConsumersHerbivores, Carnivores &

Omnivores

HEAT

Inorganic Nutrients H2O, O2 CO2, N, Minerals

HEAT

HEAT

HEAT

HEAT

Inorganic Nutrients H2O, O2 CO2, N, Minerals

Trophic Levels

Autotrophs Producers

HeterotrophsDecomposers

HeterotrophsConsumers

HEAT

This pattern of energy flow among different organisms is the TROPHIC STRUCTURE of an ecosystem.

Fate of Solar Energy

Fuels Photosynthesis Warms Earth Powers Water Cycle

ProducersConvert Solar Energy into Chemical Energy through

Photosynthesis

Producers = Autotrophs = Plants & Algae

6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 + 6O2

Producers Convert Solar Energy into Chemical Energy

through Photosynthesis Energy is stored in glucose bonds

Glucose is converted and stored as simple sugars and starch in plants

Consumers Eat other living plants, animals or microbes Get energy from preformed organic molecules

heterotrophs

Herbivore - plant eaters

Carnivore - meat eaters

Omnivore - mixed plant/animal diet

Consumers Primary Consumers

Eat Plants Herbivores

Secondary Consumers Eat Primary Consumers Carnivores

Tertiary Consumers Eat Secondary Consumer Carnivores

Detrivores Organisms that eat detritus Detritus Dead plants, animals, & microbes

& fecal wastes of animals Get energy from preformed organic

molecules Decomposers Live on detritus in such a way

that it decays Subgroup of detrivores

Food chains & webs Food chain pathways of feeding

relationships Producer-consumer relationships Parasite-host relationships

Food web Complex pattern of interconnected food chains

A food chain

Nutrie

nts

A food webN

utri

ents

Trophic levelsN

utri

ents

1st Trophic LevelProducers

2nd Trophic Level Primary Consumers

3rd Trophic Level Secondary Consumers

4th Trophic Level Tertiary Consumers