Sediment microbial enzyme activity as an indicator of nutrient limitation in Great Lakes coastal wetlands

Brian H Hill, C. M. Elonen, T. M. Jicha, A. M. Cotter, A. S. Trebitz, N. P. Danz

Research output: Contribution to journalArticlepeer-review

62 Scopus citations

Abstract

1. We compared the extracellular enzyme activity (EEA) of sediment microbial assemblages with sediment and water chemistry, gradients in agricultural nutrient loading (derived from principal component analyses), atmospheric deposition and hydrological turnover time in coastal wetlands of the Laurentian Great Lakes. 2. There were distinct increases in nutrient concentrations in the water and in atmospheric N deposition along the gradient from Lake Superior to Lake Ontario, but few differences between lakes in sediment carbon (C), nitrogen (N) or phosphorus (P). Wetland water and sediment chemistry were correlated with the agricultural stress gradient, hydrological turnover time and atmospheric deposition. 3. The N: P ratio of wetland waters and sediments indicated that these coastal wetlands were N-limited. Nutrient stoichiometry was correlated with the agricultural stress gradient, hydrological turnover time and atmospheric deposition. 4. Extracellular enzyme activity was correlated with wetland sediment and water chemistry and stoichiometry, atmospheric N deposition, the agricultural stress gradient and the hydrological turnover time. The ratios of glycosidases to peptidases and phosphatases yielded estimates of nutrient limitation that agreed with those based solely on nutrient chemistry. 5. This study, the first to link microbial enzyme activities to regional-scale anthropogenic stressors, suggests that quantities and ratios of microbial enzymes are directly related to the concentrations and ratios of limiting nutrients, and may be sensitive indicators of nutrient dynamics in wetland ecosystems, but further work is needed to elucidate these relationships.

Original languageEnglish (US)
Pages (from-to)1670-1683
Number of pages14
JournalFreshwater Biology
Volume51
Issue number9
DOIs
StatePublished - Sep 1 2006

Keywords

  • Laurentian Great Lakes
  • Microbial enzymes
  • Nutrients
  • Stoichiometry
  • Wetlands

Fingerprint Dive into the research topics of 'Sediment microbial enzyme activity as an indicator of nutrient limitation in Great Lakes coastal wetlands'. Together they form a unique fingerprint.

Cite this