Topic 5 Ecosystems Flashcards
Population
An interbreeding group of organisms of the same species occupying a particular environment
Habitat
The physical environment where a particular population or community is found
Ecosystem
A community of living organisms (biotic component) and the abiotic factors that influence them
Birth rate
The reproductive capacity of a population and the number of new individuals, derived from reproduction of time
Immigration
movement of individuals into a population of the same species
Equilibrium species
Species that control their population by competition rather than by reproduction or dispersal
Environmental resistance
Refers to environmental factors that slowdown population growth
Environment
The set of external conditions biotic and abiotic that surround an organism
Biotic
A part of the environment of an organism that is Leavin e.g. pathogens and predators
Abiotic
A part of the environment of an organism that is nonliving for example e.g. air temperature and oxygen availability
Carrying capacity
The maximum number around which the population fluctuates in a given environmemt
Ecological niche
The place where an organism is found and what it does i.e. role in the ecosystem
Abundance
The number of individuals in a species in a given area of volume
Biomass
Mass of biological material in living or recentl living organisms
Gross primary productivity GPP
Rate of production of chemical energy in organic molecules by photosynthesis in a given area in a given time measured in kjm-2y-1
Net primary productivity NPP
Energy in a plant biomass which is available to primary consumers
Primary productivity
Rate at which energy is converted by producers into biomass
Secondary productivity
Rate at which consumers convert the chemical energy of the food into biomass
Trophic levels
Position in a food chain
Succession
Change in structure and species composition of a community over time
Climax community
A stable community that has raised equilibrium with its environment and no further change accuse
Primary succession
Change in structure and species composition of a community over time in an area that has not previously been colonised
Pioneer species
The first species to colonise a new area in an ecological succession e.g. Algae lichens and mosses in a xerosere
Seral stages
The different stages in succession when a particular communities dominate e.g grasses
