Anita Ballmick

allochthonousThe input of energy and nutrients from outside the ecosystem. Compare autochthonous.

The proportion of ingested food that is assimilated by an organism.

Energy and nutrients produced within the ecosystem. Compare allochthonous.

The progressive concentration of a substance in an organism’s body over its lifetime.

An increase in the tissue concentrations of a substance at higher trophic levels that results as animals at each trophic level consume prey with increasing concentrations of the substance.

The proportion of the biomass available in an ecosystem that is ingested.

A diagram showing the connections between organisms and the food they consume.

A measure of the effect of one species’ population on the size of another species’ population.

A strongly interacting species that has a large effect on energy flow and on community structure and composition disproportionate to its abundance or biomass.

The proportion of assimilated food that is used to produce new consumer biomass.

A change in the rate of consumption at one trophic level that results in a series of changes in species abundances and species compositions at lower trophic levels.

A measure of the transfer of energy between trophic levels, consisting of the amount of energy at one trophic level divided by the amount of energy at the trophic level immediately below it.

A group of species in a community that obtain energy in similar ways, classified by the number of feeding steps by which the group is removed from auto-trophs, which are the first trophic level.

A common approach to conceptualizing trophic relationships in an ecosystem in which a stack of rectangles is constructed, each of which represents the amount of energy or biomass within one trophic level.