Changing Ecosystem Dynamics in the Laurentian Great Lakes Bottom-Up and Top-Down Regulation

Understanding the relative importance of top-down and bottom-up regulation of ecosystem structure is a fundamental ecological question, with implications for fisheries and water-quality management. For the Laurentian Great Lakes, where, since the early 1970s, nutrient inputs have been reduced, where...

Full description

Saved in:
Bibliographic Details
Published inBioscience Vol. 64; no. 1; pp. 26 - 39
Main Authors BUNNELL, DAVID B., BARBIERO, RICHARD P., LUDSIN, STUART A., MADENJIAN, CHARLES P., WARREN, GLENN J., DOLAN, DAVID M., BRENDEN, TRAVIS O., BRILAND, RUTH, GORMAN, OWEN T., HE, JI X., JOHENGEN, THOMAS H., LANTRY, BRIAN F., LESHT, BARRY M., NALEPA, THOMAS F., RILEY, STEPHEN C., RISENG, CATHERINE M., TRESKA, TED J., TSEHAYE, IYOB, WALSH, MAUREEN G., WARNER, DAVID M., WEIDEL, BRIAN C.
Format Journal Article
LanguageEnglish
Published Oxford Oxford University Press 01.01.2014
Subjects
Biomass
Ecosystem dynamics
Ecosystem management
Ecosystem structure
Ecosystems
Environmental changes
Freshwater ecosystems
Freshwater fishes
Invertebrates
Lakes
Lentic systems
Limnology
Marine ecosystems
Nutrient cycles
Overview Articles
Phytoplankton
Plankton
Predation
Time series
Trophic levels
Water quality
Watersheds
Zooplankton
trophic cascade
regime shift
wasp-waist ecosystems
invasive species
multiple stressors
Online AccessGet full text

Cover

More Information
Summary:Understanding the relative importance of top-down and bottom-up regulation of ecosystem structure is a fundamental ecological question, with implications for fisheries and water-quality management. For the Laurentian Great Lakes, where, since the early 1970s, nutrient inputs have been reduced, whereas top-predator biomass has increased, we describe trends across multiple trophic levels and explore their underlying drivers. Our analyses revealed increasing water clarity and declines in phytoplankton, native invertebrates, and prey fish since 1998 in at least three of the five lakes. Evidence for bottom-up regulation was strongest in Lake Huron, although each lake provided support in at least one pair of trophic levels. Evidence for top-down regulation was rare. Although nonindigenous dreissenid mussels probably have large impacts on nutrient cycling and phytoplankton, their effects on higher trophic levels remain uncertain. We highlight gaps for which monitoring and knowledge should improve the understanding of food-web dynamics and facilitate the implementation of ecosystem-based management.
ISSN:0006-3568
1525-3244
DOI:10.1093/biosci/bit001