Consequences of non-equilibrium resource availability across multiple time scales: the transient maxima hypothesis

TitleConsequences of non-equilibrium resource availability across multiple time scales: the transient maxima hypothesis
Publication TypeJournal Article
Year of Publication1993
AuthorsSeastedt, TR, Knapp, AK
JournalAmerican Naturalist
Volume141
Pagination621 -633
Accession NumberKNZ00427
Abstract

Nonequilibrium biotic responses to changes in resource limitation dominate the behavior of tallgrass prairie ecosystems. Rates of leaf photosynthesis on a time scale of minutes, amounts of annual plant productivity, patterns in the productivity of certain consumer groups, and amounts of soil organic matter accumulation over millennia all reflect biotic responses to frequent and recurring shifts in limiting resources. Productivity is higher during a transition period when the relative importance of an essential resource is changing than during an equilibrium interval generated by single resource limitation. These "transient maxima" are both characteristic and easily measurable in the tallgrass prairie because of the unpredictable climate and ecological constraints such as grazing and recurrent fires that modify water, nitrogen, and light availability. Such diverse phenomena as overcompensation for herbivory, the intermediate disturbance hypothesis, maximum levels of productivity observed in successional ecosystems, and widespread nitrogen limitation in terrestrial and aquatic ecosystems can be explained by biotic response to shifts in limiting resources.

URLhttp://www.jstor.org/stable/2462753