Marine downscaling of a future climate scenario in the North Sea and possible effects on dinoflagellate harmful algal blooms

2012 ◽  
Vol 29 (10) ◽  
pp. 1630-1646 ◽  
Author(s):  
Y.F. Friocourt ◽  
M. Skogen ◽  
W. Stolte ◽  
J. Albretsen
Keyword(s):  
North Sea ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Climate Scenario ◽  
Future Climate ◽  
Future Climate Scenario ◽  
The North ◽  
The North Sea

Future increase in harmful algal blooms in the North Sea due to climate change

2005 ◽  
Vol 51 (5) ◽  
pp. 31-36 ◽  
Author(s):  
L. Peperzak
Keyword(s):  
Climate Change ◽  
North Sea ◽  
Growth Rates ◽  
Ecosystem Functioning ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Cost Benefit ◽  
The North ◽  
Marine Food Chain ◽  
The North Sea

In temperate seas such as the North Sea harmful (toxic) algal blooms will probably increase as a result of climate change. This conclusion was reached after investigating the projected effect of climate change for the year 2100 in Dutch coastal waters (4°C temperature rise and increased water column stratification) on the growth rates of six harmful and two non-harmful phytoplankton species. Micro algae form the basis of the marine food chain. However, toxin-producing species may seriously disrupt the food web and lead to fish kills and human intoxication. Two species with estimated doubled growth rates in 2100, F. japonica and C. antiqua, entered Europe via ship's ballast water or shellfish imports. This stresses the need to legally regulate such invasion routes in order to prevent the import of novel species. Future toxic phytoplankton blooms may further devaluate ecosystem deliverables such as fish production or recreational use. This devaluation can be estimated by monetary value assessments that are needed in cost-benefit analyses for policy guidance. The lack of understanding of future climate, ecosystem functioning and its response to climate change calls for a scientific effort to improve our knowledge on present day coastal ecosystem functioning and its resilience.

scholarly journals The Algicidal Bacterium Kordia algicida Shapes a Natural Plankton Community

2019 ◽  
Vol 85 (7) ◽  
Author(s):  
Arite Bigalke ◽  
Nils Meyer ◽  
Lydia Alkistis Papanikolopoulou ◽  
Karen Helen Wiltshire ◽  
Georg Pohnert
Keyword(s):  
North Sea ◽  
Algal Blooms ◽  
Plankton Community ◽  
Algicidal Bacteria ◽  
Important Species ◽  
Substantial Impact ◽  
The North ◽  
Algicidal Bacterium ◽  
The North Sea ◽  
Plankton Communities

ABSTRACT Plankton communities consist of complex microbial consortia that change over time. These fluctuations can be only partially explained by limiting resources. Biotic factors such as herbivores and pathogens also contribute to the control of algal blooms. Here we address the effects of algicidal bacteria on a natural plankton community in an indoor enclosure experiment. The algicidal bacteria, introduced into plankton taken directly from the North Sea during a diatom bloom, caused the rapid decline of the bloom-forming Chaetoceros socialis within only 1 day. The haptophyte Phaeocystis, in contrast, is resistant to the lytic bacteria and could benefit from the removal of the competitor, as indicated by an onset of a bloom in the treated enclosures. This cascading effect caused by the bacterial pathogen accelerated the succession of Phaeocystis, which bloomed with a delay of only several weeks in the in situ waters at Helgoland Roads in the North Sea. The algicidal bacteria can thus modulate the community within the limits of the abiotic and biotic conditions of the local environment. Implications of our findings for plankton ecosystem functioning are discussed. IMPORTANCE Plankton communities change on a seasonal basis in temperate systems, with distinct succession patterns; this is mainly due to algal species that have their optimal timing relative to environmental conditions. We know that bacterial populations are also instrumental in the decay and termination of phytoplankton blooms. Here, we describe algicidal bacteria as modulators of this important species succession. Upon treatment of a natural plankton consortium with an algicidal bacterium, we observed a strong shift in the phytoplankton community structure, compared to controls, resulting in formation of a succeeding Phaeocystis bloom. Blooms of this alga have a substantial impact on global biogeochemical and ecological cycles, as they are responsible for a substantial proportion of primary production during spring in the North Sea. We propose that one of the key factors influencing such community shifts may be algicidal bacteria.

scholarly journals The simultaneous occurrence of surge and discharge extremes for the Rhine delta

2013 ◽  
Vol 13 (8) ◽  
pp. 2017-2029 ◽  
Author(s):  
S. F. Kew ◽  
F. M. Selten ◽  
G. Lenderink ◽  
W. Hazeleger
Keyword(s):  
North Sea ◽  
Climate Model ◽  
Global Climate ◽  
Global Climate Model ◽  
Storm Surges ◽  
Future Climate ◽  
Simultaneous Occurrence ◽  
Rhine River ◽  
The North ◽  
The North Sea

Abstract. The low-lying Netherlands is at risk from multiple threats of sea level rise, storm surges and extreme river discharges. Should these occur simultaneously, a catastrophe will be at hand. Knowledge about the likelihood of simultaneous occurrence or the so-called "compound effect" of such threats is essential to provide guidance on legislation for dike heights, flood barrier design and water management in general. In this study, we explore the simultaneous threats of North Sea storm surges and extreme Rhine river discharge for the current and future climate in a large 17-member global climate model ensemble. We use a simple approach, taking proxies of north-northwesterly winds over the North Sea and multiple~day precipitation averaged over the Rhine basin for storm surge and discharge respectively, so that a sensitivity analysis is straightforward to apply. By investigating soft extremes, we circumvent the need to extrapolate the data and thereby permit the model's synoptic development of the extreme events to be inspected. Our principle finding based on the climate model data is that, for the current climate, the probability of extreme surge conditions following extreme 20-day precipitation sums is around 3 times higher than that estimated from treating extreme surge and discharge probabilities as independent, as previously assumed. For the future climate (2070–2100), the assumption of independence cannot be rejected, at least not for precipitation sums exceeding 7 days.

scholarly journals Optical Detection of Harmful Algal Blooms in the Belgian Coastal Zone: A Cautionary Tale of Chlorophyll c3

2021 ◽  
Vol 8 ◽  
Author(s):  
Alexandre Castagna ◽  
Heidi Dierssen ◽  
Emanuele Organelli ◽  
Margarita Bogorad ◽  
Jonas Mortelmans ◽  
...  
Keyword(s):  
North Sea ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Optical Detection ◽  
Biomass Concentration ◽  
Optical Signal ◽  
Optical Data ◽  
Optical Signals ◽  
Southern North Sea ◽  
The North

Phaeocystis globosa is a nuisance haptophyte species that forms annual blooms in the southern North Sea and other coastal waters. At high biomass concentration, these are considered harmful algal blooms due to their deleterious impact on the local ecosystems and economy, and are considered an indicator for eutrophication. In the last two decades, methods have been developed for the optical detection and quantification of these blooms, with potential applications for autonomous in situ or remote observations. However, recent experimental evidence suggests that the interpretation of the optical signal and its exclusive association with P. globosa may not be accurate. In the North Sea, blooms of P. globosa are synchronous with those of the diatom Pseudo-nitzschia delicatissima, another harmful bloom-forming species with similar pigmentation and optical signature. Here we combine new and published measurements of pigmentation composition and inherent optical properties from pure cultures of several algal and cyanobacterial groups, together with environmental spectroscopy data, to identify the pigments generating the optical signals captured by two established algorithms. We further evaluate the association of those pigments and optical signals with P. globosa. We found that the interpretation of the pigment(s) generating the optical signals were incorrect and that previous methods are not specific to P. globosa, even in the context of the phytoplankton assemblage of the southern North Sea. Additionally, we found that the optical and pigment signatures of Phaeocystis species are part of a broad pigmentation trend across unrelated taxonomic groups related to chlorophyll c3 presence, with important consequences for the interpretation of pigment and optical data. We then develop and evaluate an algorithm to detect this pigmentation pattern with minimal influence of co-occurring species and elaborate general recommendations for the future development of algorithms.

scholarly journals From spawning to first-year recruitment: the fate of juvenile sole growth and survival under future climate conditions in the North Sea

2021 ◽  
Author(s):  
K E van de Wolfshaar ◽  
L Barbut ◽  
G Lacroix
Keyword(s):  
Climate Change ◽  
North Sea ◽  
Future Climate ◽  
First Year ◽  
Climate Conditions ◽  
Growth And Survival ◽  
The North ◽  
Early Arrival ◽  
The North Sea ◽  
Young Of The Year

Abstract This study shows the effect of climate change on the growth and survival of early life history stages of common sole (Solea solea) in different nursery areas of the North Sea, by combining a larval transport model with an individual-based growth model (Dynamic Energy Budget) to assess the fate from egg to young of the year at the end of the first growth season. Three scenarios of climate change, inspired by the 2040 Intergovernmental Panel on Climate Change projections, are tested and results are compared to a reference situation representative of current climate conditions. Under climate change scenarios where wind changes, water temperature increases and earlier spawning are considered, the early arrival of fish larvae in their nurseries results in larger young of the year at the end of summer. However, early arrival leads to higher mortality due to initially slow growth in spring. Future climate scenarios result in higher biomass and reduced first-year survival. How this result translates into changes at population level and stock management needs further investigation. Nonetheless, this study illustrates that processes linking life stages are paramount to understand and predict possible consequences of future climate conditions on population dynamics.

Sign in / Sign up

Export Citation Format

Share Document