Rangeland Ecology

Hierarchy of Ecological Levels Figure from: On-line biology class

Basic Energy Flow Producers Plants Decomposers Fungi & Bacteria Consumers Herbivores, Carnivores & Omnivores Inorganic Nutrients H 2 O, O 2 CO 2, N, Minerals

Trophic Levels Autotrophs Producers Heterotrophs Decomposers Heterotrophs Consumers 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

Producers Convert Solar Energy into Chemical Energy through Photosynthesis Producers = Autotrophs = Plants & Algae 6CO 2 + 6H 2 O + sunlight & chlorophyll  C6H 12 O 6 + 6O 2

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 Nutrients

A food web Nutrients

Trophic levels Nutrients 1 st Trophic Level Producers 2 nd Trophic Level Primary Consumers 3 rd Trophic Level Secondary Consumers 4th Trophic Level Tertiary Consumers