Key Concepts in Ecology and Ecosystem Interactions

Parasitism

an interaction between two organisms where the parasite benefits and the host is harmed

Biotic

a living factor in an ecosystem

Abiotic

a non-living factor in an ecosystem

Limiting factor

something in an ecosystem that limits the growth of a population

Carrying capacity

the largest size a population can be where all organisms have resources to be successful

Invasive species or non-native species

a specie that does not belong in a specific ecosystem naturally; an introduced species that often exploits its resources and outcompetes the native species in the area

10% energy transfer rule

explains the loss of 90% of energy between trophic levels; only 10% of the energy available at one level is transferred to the next level

Detritivore

obtain energy from organic waste and dead bodies; feeds on dead/decaying matter (examples: worms)

Aquatic

'relating to' water

Terrestrial

'relating to' land

Producer or Autotroph

organisms that can make their own food by photosynthesis

Heterotroph

organisms that consume producers or other consumers for food

Habitat

the specific place where an organism lives

Biodiversity

the number of different types of species living in a given area

Community

groups of organisms of different species, living in the same area. Interactions include competition, predation, symbiosis

Population

a group of organisms of the same species living in the same area

Ecosystem

a combination of the community and the physical features of the area (soil, pH, water, weather)

Biome

a major ecosystem that occurs over a large area of land; takes into account latitude and longitude and climate

Niche

how and where an organism lives and the job it performs. This includes diet, activity, how it affects energy flow in systems. THIS IS NOT THE SAME AS HABITAT

Food chain

the path of energy through the trophic levels of an ecosystem

Food web

an interconnected group of food chains

Trophic level

a specific level in an ecosystem based on the organism's source of energy (includes producers, consumers, decomposers)

Competition

an interaction between two organisms where they compete for resources

Mutualism

an interaction between two organisms where they both benefit

Commensalism

an interaction between two organisms where one benefits and the other is neither harmed nor benefited