Long-term changes in North Sea macrobenthic communities due to climate change vs. local drivers
Gerard, S. (2022). Long-term changes in North Sea macrobenthic communities due to climate change vs. local drivers. MSc Thesis. Universiteit Antwerpen/Ghent University/Vrije Universiteit Brussel: Antwerpen/Gent/Brussel. 26 pp.
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| Available in | Author |
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Document type: Dissertation
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| Keywords |
Climate change
Macrobenthos
Measurement > Granulometry
Abra alba (W. Wood, 1802) [WoRMS]; Lagis koreni Malmgren, 1866 [WoRMS]; Lanice conchilega (Pallas, 1766) [WoRMS]; Nephtys hombergii Savigny in Lamarck, 1818 [WoRMS]
Belgium, North Sea [Marine Regions]
Marine/Coastal |
| Author keywords |
Belgian Part of the North Sea (BPNS), long-term study, sand extraction |
| Abstract |
Impacts of climate change are intensively being studied on a global scale since the last decade, often using time series of biological communities as bio indicators to assess changes. Also, in the Belgian Part of the North Sea (BPNS) macrobenthic data are being collected to disentangle climate change effects vs. natural oscillations in a temperate coastal environment. However, long-term studies remain rare, despite the fact they are potentially the only reliable way to assess climate change induced shifts in ecosystems. With uni-and multivariate analyses, the effects of climate change related parameters (North Atlantic Oscillation, Sea Surface Temperature, Chlorophyll a, and salinity) vs. local factors (granulometry of the sediment) was investigated on a long-term macrobenthos dataset collected at 15 km offshore off Zeebrugge (Belgian coast). Over the years 2003-2020 the macrobenthic community composition has changed significantly on a species level driven by changes in the median grain size of the sediment. With decreasing median grain size and associated higher mud content, a trend towards a higher diversity, density, richness, and evenness was found with typical species such as Abra alba, Lanice conchilega, Nephtys homberghii, and Lagis koreni increasing in abundance since the year 2003. This is highly likely due to its close proximity to sand extraction sites such as the Thornton bank and Sierra Ventana. Climate change related effects were not detected possibly due to the limited dataset, calling for a continuation of the time series with the highest time resolution possible. This study emphasizes the required commitment to more long-term climate-based studies that includes environmental variables such as nutrients levels, contaminant concentrations, oxygen profiles, and radiation time. |
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