Environmental variations in a semi-enclosed embayment (Amvrakikos Gulf, Greece) – reconstructions based on benthic foraminifera abundance and lipid biomarker pattern
Copyright policy )Environmental variations in a semi-enclosed embayment (Amvrakikos Gulf, Greece) – reconstructions based on benthic foraminifera abundance and lipid biomarker pattern
The evolution of environmental changes during the last decades and the impact on the living biomass in the western part of Amvrakikos Gulf was investigated using abundances and species distributions of benthic foraminifera and lipid biomarker concentrations. These proxies indicated that the gulf has markedly changed due to eutrophication. Eutrophication has led to a higher productivity, a higher bacterial biomass, shifts towards opportunistic and tolerant benthic foraminifera species (e.g. Bulimina elongata, Nonionella turgida, Textularia agglutinans, Ammonia tepida) and a lower benthic species density. Close to the Preveza Strait (connection between the gulf and the Ionian Sea), the benthic assemblages were more diversified under more oxygenated conditions. Sea grass meadows largely contributed to the organic matter at this sampling site. The occurrence of isorenieratane, chlorobactane and lycopane supported by oxygen monitoring data indicated that anoxic (and partly euxinic) conditions prevailed seasonally throughout the western part of the gulf with more severe oxygen depletion towards the east. Increased surface water temperatures have led to a higher stratification, which reduced oxygen resupply to bottom waters. Altogether, these developments led to mass mortality events and ecosystem decline in Amvrakikos Gulf.
Biogeosciences, 9 (12)
ISSN:1726-4170
- ETH Zurich Switzerland
- Swiss Federal Institute of Aquatic Science and Technology Switzerland
- University of Patras Greece
- ETH Zurich Switzerland
- Hellenic Centre for Marine Research Greece
Microsoft Academic Graph classification: Biomass (ecology) biology Ecology biology.organism_classification Anoxic waters Foraminifera Oceanography Ammonia tepida Productivity (ecology) Benthic zone Abundance (ecology) Environmental science Eutrophication
Library of Congress Subject Headings: lcsh:QE1-996.5 lcsh:Life lcsh:Geology lcsh:QH501-531 lcsh:QH540-549.5 lcsh:Ecology
Medical Subject Headings: geographic locations
Ecology, Evolution, Behavior and Systematics, Earth-Surface Processes
Ecology, Evolution, Behavior and Systematics, Earth-Surface Processes
Microsoft Academic Graph classification: Biomass (ecology) biology Ecology biology.organism_classification Anoxic waters Foraminifera Oceanography Ammonia tepida Productivity (ecology) Benthic zone Abundance (ecology) Environmental science Eutrophication
Library of Congress Subject Headings: lcsh:QE1-996.5 lcsh:Life lcsh:Geology lcsh:QH501-531 lcsh:QH540-549.5 lcsh:Ecology
Medical Subject Headings: geographic locations
6917
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citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).25 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Average impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 10% citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).25 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Average impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 10%
Citations provided by BIP!Popularity provided by BIP!- ETH Zurich Switzerland
- Swiss Federal Institute of Aquatic Science and Technology Switzerland
- University of Patras Greece
- ETH Zurich Switzerland
- Hellenic Centre for Marine Research Greece
The evolution of environmental changes during the last decades and the impact on the living biomass in the western part of Amvrakikos Gulf was investigated using abundances and species distributions of benthic foraminifera and lipid biomarker concentrations. These proxies indicated that the gulf has markedly changed due to eutrophication. Eutrophication has led to a higher productivity, a higher bacterial biomass, shifts towards opportunistic and tolerant benthic foraminifera species (e.g. Bulimina elongata, Nonionella turgida, Textularia agglutinans, Ammonia tepida) and a lower benthic species density. Close to the Preveza Strait (connection between the gulf and the Ionian Sea), the benthic assemblages were more diversified under more oxygenated conditions. Sea grass meadows largely contributed to the organic matter at this sampling site. The occurrence of isorenieratane, chlorobactane and lycopane supported by oxygen monitoring data indicated that anoxic (and partly euxinic) conditions prevailed seasonally throughout the western part of the gulf with more severe oxygen depletion towards the east. Increased surface water temperatures have led to a higher stratification, which reduced oxygen resupply to bottom waters. Altogether, these developments led to mass mortality events and ecosystem decline in Amvrakikos Gulf.
Biogeosciences, 9 (12)
ISSN:1726-4170