Article
The spatial and temporal dynamics of deep chlorophyll layers in high-mountain lakes: effects of nutrients, grazing and herbivore nutrient recycling as growth determinants
Journal of Plankton Research
(2006)
Abstract
Deep chlorophyll layers (DCL) are a common feature of oligotrophic lakes, yet the mechanisms that form and maintain them are not understood fully. These phytoplankton populations occur in the metalimnia of lakes where light levels are moderate to low, and where nutrient levels and zooplankton grazing pressure are different than in the epilimnion. To test the importance of nutrients and grazing pressure for algal growth in different lake strata, microcosm experiments and monitoring were conducted in two oligotrophic lakes in the Rocky Mountains of North America that contain DCL. In situ microcosm experiments with natural phytoplankton communities from three depth strata were conducted with macronutrient additions and with and without the natural zooplankton grazing communities. Alkaline phosphatase assays and the in situ microcosm experiments indicated less nutrient limitation in the metalimnia than in the epilimnia of both lakes. Zooplankton grazing in the experiments decreased algal population growth rates by as much as 6% day−1, with impacts shifting to progressively deeper strata over the summer.
Disciplines
Publication Date
2006
DOI
https://doi.org/10.1093/plankt/fbi101
Citation Information
Wayne A. Wurtsbaugh. "The spatial and temporal dynamics of deep chlorophyll layers in high-mountain lakes: effects of nutrients, grazing and herbivore nutrient recycling as growth determinants" Journal of Plankton Research Vol. 28 Iss. 1 (2006) p. 65 - 86 Available at: http://works.bepress.com/wayne_wurtsbaugh/227/