Definitions

• Abiotic Factor


  A non-living factor within an ecosystem eg. the physical landscape, weather, soil salinity, temperature
• Biology


  the study of living things
• Biotic Factor


  a living factor within an ecosystem eg. animals, plants
• Biodiversity


  the variety and variability of all living things and their interactions
• Clade


  a taxonomic group that contains all the descendant of a common ancestor

  
• Cladogram


  Diagram constructed using cladistics that shows the evolutionary relationships between organisms

  
• Ecosystems


  An ecosystem is a system that environments and their organisms form through the interaction between the biotic and abiotic factors.
• Phylogeny


  The evolutionary ancestry of a species.

  
• eutrophication 


  a process that occurs when excess nutrients, particularly nitrogen and phosphorus, enter a body of water and becomes highly concentrated, leading to excess growth or organisms (eg. algae)
• competition


  an interaction between living things that occurs when individuals compete for a resource that limits their survival and reproduction
• Community


  a group of population of different species in an ecosystem in close enough proximity to interact
• environment


  the abiotic and biotic factors of an area
• interspecific

  describes the interactions/relationships between members of the SAME species
• intRAspecific


  describes the interactions/relationships between members of DIFFERENT species
• mutualism


  a symbiotic relationship which benefits both species in the relationship
• parasitism


  a relationship where one species (parasite) derives nutrients from another species (host) who is harmed but not always killed.
• substrate


  a supporting surface on which an organism grows
• symbiosis


  a relationship between individuals in two or more species that is beneficial to at least one species
• biogeochemical cycle


  the cycling of matter through biotic and abiotic components in an ecosystem
• biomass


  the total biological matter (living or dead) in a given area at a given time that can be used as an energy source
• carbon sink


  a biogeochemical reservoir, such as plants or oceans, that stores carbon because it absorbs more carbon than it releases
• decomposer


  organisms that break down complex organic matter into nutrients (eg. fungi, bacteria)
• detritivore


  an organism that feeds on dead plants or animal matter
• detritus


  organic wastes, including faeces and dead tissue
• food chain


  model that represents the transfer of energy from its source in autotrophs to other trophic levels.
• food web


  a diagram that shows how different organisms feed on each other, thereby transferring energy though an ecosystem; the interconnection of food chains in an ecosystem.
• fundamental niche


  the potential role an organism could fulfil if there were no competitors, predators or parasites
• Gross primary productivity (GPP)


  the total organic matter in an ecosystem produced by photosynthesis
• keystone species


  species of relatively low abundance that has a disproportionately large influence over lower trophic levels, determining the coexistence of other species in an area
• net primary productivity (NPP)

  the amount of organic matter actually available to herbivores; the GPP minus the energy required by the producers themselves
• realised niche


  the actual ecological niche a species inhabits
• carrying capacity


  the maximum population size of a species that can be supported in a given environment (represented by K)
• density


  the number of individuals in a given area
• climate


  the long term predictable atmospheric weather conditions at a site over a period. Climate is made up of variables such as rainfall, temperature, sunlight intensity and wind.