Effects of Snail Grazing on the Diversity and Structure of a Periphyton Community in a Eutrophic Pond
- 1 October 1989
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Fisheries and Aquatic Sciences
- Vol. 46 (10), 1698-1704
- https://doi.org/10.1139/f89-215
Abstract
Periphyton diversity was highest at low to intermediate levels of grazing by the freshwater snail Physella and suppressed at high grazer densities, in partial support of the intermediate disturbance hypothesis. For the first time, the response curve of algal biomass versus a range of snail densities was used to establish low, intermediate, and high levels of community disturbance. Physella densities corresponding to these levels were added to net enclosures in a small eutrophic pond, to examine differences in attached algal cell densities and diversity after 20 d. Algal standing crop was enhanced in low and depressed in intermediate and higher grazer treatments. Five categories of attached algal response to grazing were identified: (1) filamentous algae suppressed at high grazing pressure; (2) rosette or filamentous taxa suppressed at moderate to high levels of grazing; (3) algae resistant to grazing via sediment-associated recruitment; (4) low profile algae with highest densities at moderate grazing, and; (5) prostrately attached taxa enhanced at moderate and high grazing levels, in contrast to marine macroalgal communities, the primary mechanism mediating community response to different levels of grazing was the morphology of algal attachment.This publication has 39 references indexed in Scilit:
- THE ECOLOGICAL IMPLICATIONS OF GROWTH FORMS IN EPIBENTHIC DIATOMS 1Journal of Phycology, 1987
- Effects of Discharge Reduction on Diatom Colonization below a Large Hydroelectric DamJournal of the North American Benthological Society, 1986
- Selective grazing on periphyton: a determinant of freshwater gastropod microdistributionsFreshwater Biology, 1986
- Plankton Community Structure and Limnetic Primary ProductionThe American Naturalist, 1984
- Stream Periphyton and Insect Herbivores: An Experimental Study of Grazing by a Caddisfly PopulationEcology, 1983
- Competition and Coexistence among the Grazing Snail Lymnaea, Chironomidae, and Mircrocrustacea in an Arctic Epilithic Lacustrine CommunityEcology, 1983
- Herbivory, Algal Distribution, and the Maintenance of Between-Habitat Diversity on a Tropical Fringing ReefThe American Naturalist, 1981
- Experimental Evaluation of Ecological Dominance in a Rocky Intertidal Algal CommunityEcological Monographs, 1975
- Periphyton Production and Grazing Rates in a Stream Measured with a 32 P Material Balance MethodOikos, 1972
- The Effect of Grazing by Tadpoles on the Structure of a Periphyton CommunityEcology, 1968