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Biogeochemical Indicators of Nutrient
Enrichments in Wetlands:
The Microbial Response as a Sensitive
Indicator of Wetland Eutrophication
Salvador Sánchez-Carrillo, K. Ramesh Reddy, Kanika S. Inglett,
Miguel Álvarez-Cobelas and Raquel Sánchez-Andrés
S. Sánchez-Carrillo () · M. Álvarez-Cobelas
National Museum of Natural Sciences, MNCN-CSIC, Serrano 115-dpdo, 28006 Madrid, Spain
e-mail: sanchez.carrillo@mncn.csic.es
K. R. Reddy · K. S. Inglett
Deptartment Soil and Water Science, University of Florida, 106 Newell Hall,
P.O. Box 110510, Gainesville, FL 32611-0510, USA
R. Sánchez-Andrés
Royal Botanic Garden, RJB-CSIC, Pza de Murillo 2, 28014, Madrid, Spain
Abstract
In wetlands it is still usual to use the same indicators of eutrophication which were developed
to study the effects of nutrient enrichment in lakes; however, since hydroecology and biogeochemistry of wetlands is significantly different from lakes, monitoring of these indicators
does not allow a good diagnosis of the changes undergone by the wetland ecosystem under
nutrient enrichment scenarios. Microbial activities and their respective community responses
have been considered as a measure of ecosystem stability and an indicator of ecosystem perturbation through changes on functional properties associated with nutrient cycling. As in
most aquatic ecosystems, the addition of a limiting nutrient to wetland ecosystems promotes
primary productivity and stimulates microbial processes. As nutrient loading increase, biogeochemical processes in wetlands are altered, changing their concentrations in water and
soil, and therefore, nutrient fluxes and cycling. Nutrient enrichment induces changes in soil
physicochemical and microbiological characteristics that may then serve as indicators of nutrient enrichment. In this review, a set of microbial community measurements known to be
sensitive to nutrient enrichment in aquatic systems, such as extracellular enzyme activities,
respiratory activities, microbial biomass C, N, and P, and microbially mediated N and P turnover rates have been used to characterize physiological response of the microbial community
to wetland eutrophication. Some indicators as metabolic efficiency and phosphatase activity
clearly reflect the main shifts on wetland ecosystem processes induced by nutrient enrichment and may be considered better than those that are currently used to assess the effects of
eutrophication. Moreover, the combined use of different ecophysiological measurements such
as extracellular enzymatic ratios and microbial biomass under resource allocation models and
ecological stoichiometry demonstrates that ecophysiological measures are sensitive indicators of wetland eutrophication. Further studies are needed refining this approach to get the
complex biogeochemical variability of the different wetland types, and to move from a sitebased heuristic model to a holistic approach, describing eutrophication patterns in wetlands.
Keywords
Eutrophication · Nutrient enrichment · Carbon · Nitrogen · Phosphorus
A. A. Ansari, S. S. Gill (eds.), Eutrophication: Causes, Consequences and Control,
DOI 10.1007/978-94-007-7814-6_15, © Springer Science+Business Media Dordrecht 2014
15
Biogeochemical Indicators of Nutrient
Enrichments in Wetlands:
The Microbial Response as a Sensitive
Indicator of Wetland Eutrophication
Salvador Sánchez-Carrillo, K. Ramesh Reddy, Kanika S. Inglett,
Miguel Álvarez-Cobelas and Raquel Sánchez-Andrés
S. Sánchez-Carrillo () · M. Álvarez-Cobelas
National Museum of Natural Sciences, MNCN-CSIC, Serrano 115-dpdo, 28006 Madrid, Spain
e-mail: sanchez.carrillo@mncn.csic.es
K. R. Reddy · K. S. Inglett
Deptartment Soil and Water Science, University of Florida, 106 Newell Hall,
P.O. Box 110510, Gainesville, FL 32611-0510, USA
R. Sánchez-Andrés
Royal Botanic Garden, RJB-CSIC, Pza de Murillo 2, 28014, Madrid, Spain
Abstract
In wetlands it is still usual to use the same indicators of eutrophication which were developed
to study the effects of nutrient enrichment in lakes; however, since hydroecology and biogeochemistry of wetlands is significantly different from lakes, monitoring of these indicators
does not allow a good diagnosis of the changes undergone by the wetland ecosystem under
nutrient enrichment scenarios. Microbial activities and their respective community responses
have been considered as a measure of ecosystem stability and an indicator of ecosystem perturbation through changes on functional properties associated with nutrient cycling. As in
most aquatic ecosystems, the addition of a limiting nutrient to wetland ecosystems promotes
primary productivity and stimulates microbial processes. As nutrient loading increase, biogeochemical processes in wetlands are altered, changing their concentrations in water and
soil, and therefore, nutrient fluxes and cycling. Nutrient enrichment induces changes in soil
physicochemical and microbiological characteristics that may then serve as indicators of nutrient enrichment. In this review, a set of microbial community measurements known to be
sensitive to nutrient enrichment in aquatic systems, such as extracellular enzyme activities,
respiratory activities, microbial biomass C, N, and P, and microbially mediated N and P turnover rates have been used to characterize physiological response of the microbial community
to wetland eutrophication. Some indicators as metabolic efficiency and phosphatase activity
clearly reflect the main shifts on wetland ecosystem processes induced by nutrient enrichment and may be considered better than those that are currently used to assess the effects of
eutrophication. Moreover, the combined use of different ecophysiological measurements such
as extracellular enzymatic ratios and microbial biomass under resource allocation models and
ecological stoichiometry demonstrates that ecophysiological measures are sensitive indicators of wetland eutrophication. Further studies are needed refining this approach to get the
complex biogeochemical variability of the different wetland types, and to move from a sitebased heuristic model to a holistic approach, describing eutrophication patterns in wetlands.
Keywords
Eutrophication · Nutrient enrichment · Carbon · Nitrogen · Phosphorus
A. A. Ansari, S. S. Gill (eds.), Eutrophication: Causes, Consequences and Control,
DOI 10.1007/978-94-007-7814-6_15, © Springer Science+Business Media Dordrecht 2014