Principles of Ecology 1.1 Science of Ecology
Principles of Ecology 1.1 Science of Ecology Presented by Wendy Noffke & Loren Davis
Introduction • Ecology: how living things interact with the environment and each other
Environmental Influences • Abiotic factors: nonliving, sunlight, soil, temperature, water • Biotic factors: living aspects, other species & others members of the same species
The Ecosystem • Ecosystem: all biotic & nonbiotic factors in the area and the interaction • Need constant energy input – most use light, a few use chemicals • Matter is constantly recycled – water & minerals • Niche: role of a species in ecosystem, food & how it obtains it, how it survives • Habitat: physical environment where species lives
Competitive Exclusion Principle • 2 species cannot occupy the same niche in the same place for very long • They would compete for resources – one is likely to outcompete the other
Flow of Energy - Producers • Producers / autotrophs: produce their own food • Photoautotrophs: use energy from sunlight to make food by photosynthesis – plants, algae, certain bacteria • Chemoautotrophs: use chemical compounds to make food by chemosynthesis – some bacteria, archae
Flow of Energy - Consumers • Consumers: depend on others for food • Herbivores: consumer produces such as plants / algae • Carnivores: consume animals • Omnivores: consume both plants & animals
Flow of Energy – Consumers / Decomposers • Decomposers: breakdown remains / wastes & release simple organic molecules into environment • Scavengers: consume soft tissue of dead animals • Detrivores: consume detritus, dead leaves, animal feces, & other organic debris • Saprotrophs: feed on remaining matter after other decomposers do their work
Food Chains & Food Webs • Food chain: single pathway through which energy & matter flow • Food web: multiple pathways through which energy & matter flow through an ecosystem
Trophic Levels Feeding positions in food chain / food web Trophic Level
Where it gets food
1st – producer
Makes own food
2nd – primary consumer
Consumers producers
3rd – secondary consumer
Consumers primary producers
4th – tertiary consumer
Consumers secondary producers
Trophic Levels & Energy • Energy passed up food chain/ web from lower levels to higher levels, but only 10% available to the next level • Rarely enough energy for a 5th trophic level
Trophic Levels & Biomass • Biomass: total mass of organisms at a trophic level • With less energy at higher levels, means fewer organisms • Organisms size is greater but smaller numbers of them mean less biomass
Introduction • Ecology: how living things interact with the environment and each other
Environmental Influences • Abiotic factors: nonliving, sunlight, soil, temperature, water • Biotic factors: living aspects, other species & others members of the same species
The Ecosystem • Ecosystem: all biotic & nonbiotic factors in the area and the interaction • Need constant energy input – most use light, a few use chemicals • Matter is constantly recycled – water & minerals • Niche: role of a species in ecosystem, food & how it obtains it, how it survives • Habitat: physical environment where species lives
Competitive Exclusion Principle • 2 species cannot occupy the same niche in the same place for very long • They would compete for resources – one is likely to outcompete the other
Flow of Energy - Producers • Producers / autotrophs: produce their own food • Photoautotrophs: use energy from sunlight to make food by photosynthesis – plants, algae, certain bacteria • Chemoautotrophs: use chemical compounds to make food by chemosynthesis – some bacteria, archae
Flow of Energy - Consumers • Consumers: depend on others for food • Herbivores: consumer produces such as plants / algae • Carnivores: consume animals • Omnivores: consume both plants & animals
Flow of Energy – Consumers / Decomposers • Decomposers: breakdown remains / wastes & release simple organic molecules into environment • Scavengers: consume soft tissue of dead animals • Detrivores: consume detritus, dead leaves, animal feces, & other organic debris • Saprotrophs: feed on remaining matter after other decomposers do their work
Food Chains & Food Webs • Food chain: single pathway through which energy & matter flow • Food web: multiple pathways through which energy & matter flow through an ecosystem
Trophic Levels Feeding positions in food chain / food web Trophic Level
Where it gets food
1st – producer
Makes own food
2nd – primary consumer
Consumers producers
3rd – secondary consumer
Consumers primary producers
4th – tertiary consumer
Consumers secondary producers
Trophic Levels & Energy • Energy passed up food chain/ web from lower levels to higher levels, but only 10% available to the next level • Rarely enough energy for a 5th trophic level
Trophic Levels & Biomass • Biomass: total mass of organisms at a trophic level • With less energy at higher levels, means fewer organisms • Organisms size is greater but smaller numbers of them mean less biomass
