Temporal and Spatial Scales in Phytoplankton Ecology. Mechanisms, Methods, Models, and Management

Abstract

Depcarfrnurzf of Biology, Mcil4usfer fiiversify, Hamilfort, Onr. HARRIS, G. P. 1980. Temporal and spatial scales in phytoplankton eco1ogy. Mechanisms, methods, models, and management. Can. 3. Fish. Aquat. Sci. 319: 879-900.This article is essentially a review of the temporal and spatial scales iaf variability in both marine and freshwater planktonic environnlents and the algal responses to those scales. I assert that therc are problerns with our present understanding of thew scales and the use of imapprapriate assumptions concerming the occurrence of steady-state conditions. In a nonsteady-state environment the concepts of limiting nutrients must be changed, and the extrapolation from culture to field conditions is fraught with problems. In this paper I revlew the evidence for the existence and importance of small-scale, high frequency and large-scale, Ic~w frequency variation in the planktonic environment and show that mach variation fu~~darnentalIy affects our understanding of existing processes. Methodology and models nalust also reflect the true scales of variability which exist. I show that there are, at present, problems with our understanding of planktonic processes which greatly atfect our ability to manage water qaaality. New concepts and models are urgently needed. Finally I propose a ncw model of community structure and process in variable envircrn~nents which accoaants for the correct 'algal' scales of perturbation and response and allows certain predictions to be mads. I t is possible to reconcile certain problems and controversies i~, the literature by the use of such a model. An enhanced ahi1ity lo manage planktonic systerns should result from an improved understanding of the true scales of variability which exist. HARRIS, G. lB. 1980. Temporal and spatial scales in phytoplankton ecology. Mechanisms, naethods, n~odels, and management. Can. J. Fish. Aquat. Sci. 37: $77-900.Le prksent article est essentiellernent urie revue des echelles de variabilile temporelle et spatiale dans des environnements tant marins que d'eau douce et lies rkponses algaies 2 ces echelles. Je soaltiens que notre csmpr6hensiora actiielle de ccs Cchelles ek B'utilisation d'hypothises inapproprikes concernant l'occurrence de conditions dVCcluilibr-e laissent B dksirer. Dans un environraement nons en Cyuilibre, il fauiira modifier les notions d76I6ments nutritifs limitatifs, el l'extrapolation cle conditions d'Clevage B des coilditions sur le terrain est pleine de danger. Je passe ici en revue les preuvcs de I'existcnce et de B'importance d'une petite @cheile, d'une haute frkcjuence ct grande kchelle et er~fin d'une variation h faible frtquence de I'enviroianememt pla~~ctonique; je d h s n t r e de plus qti'rane telk variation affecte fc~ratiamentalcment notre cornpr6hension des processus actuels. La rnClhodologie et Ics rnodkles doivent arlssi seflCter les kclmelles de varlabilitc qui existent dans la rCalitC. Je dri-rnontrc l'existence cle problkmes aoklchant notre compr6hension des processus planctoniq~ies, influant granderrl...

The Annual Cycle of Kiel Bight Plankton: A Long-Term Analysis

“…The presence of such long-scale temporal shifts indicate that the small time scales of the immediate growth environment cannot sufficiently account for the success of a species. Harris (1980) has stressed that more attention should be paid to the various time scales of phytoplankton response to its environment. He suggested that smaller time scales would be of greater importance.…”

Movements of Marine Fish and Decapod Crustaceans: Process, Theory and Application

“…Researchers that practice landscape ecology recognise that ecological patterns and processes operate at a range of scales in time and space and that many organisms respond to this hierarchically. This organism-based perspective means that 'habitat' and the relevant patterns and processes in the surrounding environment are defined and scaled by the activities and responses of the organisms of interest (Wiens, 1976;Harris, 1980;Addicott et al, 1987;Morris, 1987;Wiens and Milne, 1989;Kotliar and Wiens, 1990;Pearson et al, 1996;McAlpine et al, 1999).…”

Ecological nitrogen-to-phosphorus stoichiometry at station ALOHA

“…The response of the microbial community to these event scale phenomena will depend upon the frequency and duration of the pulse (Harris, 1980;Robarts et al, 1998). For example, short-term events have physiological consequences whereas long-duration events could lead to species shifts and ecosystem change.…”