Interplay between r- and K-strategists leads to phytoplankton underyielding under pulsed resource supply

Papanikolopoulou, L. A., Smeti, E., Roelke, D. L., Dimitrakopoulos, P. G., Kokkoris, G. D., Danielidis, D. B. and Spatharis, S. (2018) Interplay between r- and K-strategists leads to phytoplankton underyielding under pulsed resource supply. Oecologia, 186(3), pp. 755-764. (doi: 10.1007/s00442-017-4050-x) (PMID:29299673)

Abstract

Fluctuations in nutrient ratios over seasonal scales in aquatic ecosystems can result in overyielding, a condition arising when complementary life-history traits of coexisting phytoplankton species enables more complete use of resources. However, when nutrient concentrations fluctuate under short-period pulsed resource supply, the role of complementarity is less understood. We explore this using the framework of Resource Saturation Limitation Theory (r-strategists vs. K-strategists) to interpret findings from laboratory experiments. For these experiments, we isolated dominant species from a natural assemblage, stabilized to a state of coexistence in the laboratory and determined life-history traits for each species, important to categorize its competition strategy. Then, using monocultures we determined maximum biomass density under pulsed resource supply. These same conditions of resource supply were used with polycultures comprised of combinations of the isolated species. Our focal species were consistent of either r- or K-strategies and the biomass production achieved in monocultures depended on their efficiency to convert resources to biomass. For these species, the K-strategists were less efficient resource users. This affected biomass production in polycultures, which were characteristic of underyielding. In polycultures, K-strategists sequestered more resources than the r-strategists. This likely occurred because the intermittent periods of nutrient limitation that would have occurred just prior to the next nutrient supply pulse would have favored the K-strategists, leading to overall less efficient use of resources by the polyculture. This study provides evidence that fluctuation in resource concentrations resulting from pulsed resource supplies in aquatic ecosystems can result in phytoplankton assemblages' underyielding.

• Item Type: Articles
• Keywords: Competition, nutrient limitation, nutrient pulses, resource saturation, species traits.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Spatharis, Dr Sofie
• Authors: Papanikolopoulou, L. A., Smeti, E., Roelke, D. L., Dimitrakopoulos, P. G., Kokkoris, G. D., Danielidis, D. B., and Spatharis, S.
• College/School: College of Medical Veterinary and Life Sciences > School of Life Sciences; College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Oecologia
• Publisher: Springer
• ISSN: 0029-8549
• ISSN (Online): 1432-1939
• Published Online: 03 January 2018
• Copyright Holders: Copyright © 2018 Springer-Verlag GmbH Germany, part of Springer Nature
• First Published: First published in Oecologia 186(3): 755-764
• Publisher Policy: Reproduced in accordance with the publisher copyright policy