Introduction to Communities Flashcards
What is community ecology?
Studies patterns and processes involving at least two species at a defined location.
What is ecosystem ecology?
Studies one or more communities together with their abiotic surroundings. Focuses on fluxes and cycles of energy.
What is macro-ecology?
Studies species distribution and abundance at large spatial and temporal scales and how these contribute to diversity. Includes the use of large scale environmental factors.
What are trophic levels?
Subset within a community that acquire energy in similar ways. Conceptually useful but encounters problems in assigning real species to a single trophic level as many are omnivorous. E.g. primary producers, primary consumers and secondary consumers.
What is a guild?
A collection of species that consume the same class of environmental resources in similar ways with no taxonomic restriction on membership.
What is an assemblage?
A set of taxonomically related species within a community.
What is species richness and species-area relationships?
Species richness - The number of species in a community or location
Species-area relationships - General law in ecology, species richness should always be measured in terms of a known sampling area.
What is alpha, beta and gamma diversity?
Alpha - The amount of diversity found within a single habitat/patch.
Beta - Rate of turnover in species encountered across habitats.
Gamma - The total species richness within a wider region, the sum of alpha and beta diversity.
What is species composition?
The identity of species within a community. Takes into account that each species has a distinct ecological role/niche.
What is the organismic definiton of a community?
Species act as organs, with succession acting as growth, development and repair. Results in directed patterns of community development and a climax state that persists indefinitely unless the environment changes or a new species migrates in.
What is the individualistic definition of a community?
Species’ abundance acts independently of one another through successional time. They do not co-occur in mutually beneficial associations. Communities are a chance collection of species with individual physiological requirements, allowing them to exploit a location.
