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Supplementary data
No full textFor nanoSIMS measurements of R. mucilaginosa cells, we analyzed three sample sets: (i) the original inoculum (Control), (ii) after incubation with 13C-labelled polyethylene without and (iii) with UV-treatment. We measured a total of 1144 regions of interest (ROIs, i.e., corresponding to 1144 individual cells).
For IRMS and GCMS measurements we measured 3 replicates for the development of ?13C-CO2 values and CO2 concentration in incubations with R. mucilaginosa (RM) and with 13C-polyethylene (PE), with prior UV-treatment (+UV) and without (-UV) as the sole carbon source as well as in incubations with UV-treated 13C-polyethylene (PE) without R. mucilaginosa
NIOZ fyke programme Stuifdijk
No full textThe Royal NIOZ collects data on the Wadden Sea fish community using traditional fixed gear at a specific location (Lat 52.997N, Long 4.775E) since 1960. The fixed gear is known as a 'kom-fyke' and is a passive fish trap consisting of a 200-m net running from the beach towards deeper waters (the stretched mesh size is 20 mm). This net guides migrating fish towards 2 chambers / traps and into a fyke where they can be collected. The catch is collected each day in spring (late March to early July) and in fall (late August to early November) and netting is removed in the summer (due to algae) and winter (due to storms). This data summarises the catch information as seasonal catch per unit effort (total numbers of fish caught per season, divided by the total number of fishing days in the season), for each year 1980-2019. Seasons are spring and fall, as defined above.
NB Dec 2025: datafile was corrected to include a larger period of years, two fyke locations (1 = Stuifdijk and 3 = Schanserwaard), and a data correction due to earlier errors
Cruise Report 64PE407
No full textCruise Report for cruise nr. 64EP407; Public version (GDPR compliant
OHGDGT global surface sediments data
No full textThis file contains surface sediment data from the global ocean used in the study 'Evaluating isoprenoidal hydroxylated GDGT-based temperature proxies in surface sediments from the global ocean'. The excel sheet contains information regarding the surface sediments, their location, enivironmental parameters from each location extracted from WOA database, peak area of iso-GDGTs and OH-isoGDGTs, proxy indices discussed in the study and references for previously published data
Influence of Irradiance and Temperature on the Virus MpoV-45T Infecting the Arctic Picophytoplankter Micromonas polaris - Data
No full textArctic marine ecosystems are currently undergoing rapid changes in temperature and light availability. Picophytoplankton, such as Micromonas polaris, are predicted to benefit from such changes. However, little is known about how these environmental changes affect the viruses that exert a strong mortality pressure on these small but omnipresent algae. Here we report on one-step infection experiments, combined with measurements of host physiology and viability, with 2 strains of M. polaris and the virus MpoV-45T under 3 light intensities (5, 60 and 160 ?mol quanta m?2 s?1), 2 light period regimes (16:8 and 24:0 h light:dark cycle) and 2 temperatures (3 and 7?C). Our results show that low light intensity (16:8 h light:dark) delayed the decline in photosynthetic efficiency and cell lysis, while decreasing burst size by 46%. In contrast, continuous light (24:0 h light:dark) shortened the latent period by 5 h for all light intensities, and even increased the maximum virus production rate and burst size under low light (by 157 and 69%, respectively). Higher temperature (7?C vs 3?C) led to earlier cell lysis and increased burst size (by 19%), except for the low light conditions. These findings demonstrate the ecological importance of light in combination with temperature as a controlling factor for Arctic phytoplankton host and virus dynamics seasonally, even more so in the light of global warming
Nodosarids_dataset2023
No full textThis the the excel file containing the data-set for the publication: Element/Ca ratios in Nodosariida (Foraminifera) and their potential application for paleoenvironmental reconstructions
Annual biogeochemical dynamics in the Western Scheldt
No full textEstuarine intertidal sediments are important centres for organic matter remineralization and nutrients recycling.
Nevertheless, there is limited understanding regarding how these processes occur along the salinity gradient and
their seasonality. Here, we report on the seasonal biogeochemical cycles from three types of intertidal sedimentary
habitats (freshwater, brackish and marine) located in the Western Scheldt estuary (The Netherlands and
Belgium). A full year of solute fluxes, porewater nutrient and sediment pigment concentrations at a monthly
resolution revealed clear differences in the biogeochemistry of the three sites, indicating that environmental
conditions determined the local nutrient dynamics. Temperature controlled sediment oxygen consumption rates
and nutrient fluxes, but also affected pore water nutrient concentrations up to 14 cm deep. Fresh and brackish
sediments had a net influx of dissolved inorganic nitrogen (DIN) (?? 1.62 mmol m?? 2 d?? 1 and -2.84 mmol m?? 2 d?? 1,
respectively), while only the freshwater sediments showed a net influx of phosphate (?? 0.07 mmol m?? 2 d?? 1). We
estimated that intertidal sediments remineralized a total of 10,000 t C y?? 1, with 97% of mineralization occurring
in the brackish and marine parts. Overall, sediments removed 11% (1500 t N y?? 1) and 15% (~200 t P y?? 1) of the
total nitrogen and phosphorus entering the estuary from riverine input. Moreover, observations revealed the
historical improvement of water quality resulting from water treatment policies. This spatiotemporal study of
OM remineralization and early diagenesis in estuarine systems highlights the importance of intertidal sediments
for estuarine systems. Our observations can be used in models to predict estuarine biogeochemistry or assess
climate change scenarios
Hydrography and velocity data from the Long-term Ocean Circulation Observations (LOCO) mooring in the central Irminger Sea: Deployment thirteen (LOCO2_13) August 2016 to June 2018
No full textThe data set under this specific DOI contains data from the thirteenth LOCO2 deployment (LOCO2_13), from 3 August 2016 to 16 June 2018.
This is the last LOCO2 deployment. Data from other deployments can be found through the related identifyers.
The LOCO2 mooring was started as part of the Dutch Long-term Ocean Circulation Observations project. LOCO2 was moored in the central Irminger Sea at approximately 59.2N, 39.5W from summer 2003 until summer 2018. It was equipped with Acoustic Doppler Current Profilers for the upper ocean (2500m) circulation, a near bottom SBE37 to record the temperature and salinity of the Denmark Strait Overflow Water and (from the 10th deployment onwards) another SBE37 at around 150m. A McLane Moored Profiler (MMP) equipped with a CTD was programmed to make profiles along the mooring cable between ~150m depth and ~2400m depth.
LOCO2 was positioned in the center of the Irminger Gyre, underneath the strong atmospheric forcing of the Greenland Tip Jet, in order to study deep winter convection in the Irminger Sea. Data and results are described in the following publications:
- de Jong, M. F., van Aken, H. M., V?ge, K., and R. S. Pickart (2012). Convective mixing in the central Irminger Sea: 2002-2010. Deep-Sea Research I, 63, 36-51. https://doi.org/10.1016/j.dsr.2012.01.003
- van Aken, H. M., and M. F. de Jong (2012). Hydrographic variability of Denmark Strait Overflow Water near Cape Farewell with multi-decadal to weakly time scales. Deep-Sea Research I, 66, 41-50. https://doi.org/10.1016/j.dsr.2012.04.004
- de Jong, M. F. and L. de Steur (2016). Strong winter cooling over the Irminger Sea in winter 2014-2015, exceptional deep convection, and the emergence of anomalously low SST. Geophysical Research Letters, 43, 13, 7106-7113. https://doi.org/10.1002/2016GL069596
- de Jong, M.F., M. Oltmanns, J. Karstensen, and L. de Steur (2018). Deep convection in the Irminger Sea observed with a dense mooring array. Oceanography 31(1):50?59. https://doi.org/10.5670/oceanog.2018.109
- de Jong, M.F., Fogaren, K.E., Le Bras, I., Trafford, L. and H. Palevsky (submitted 2023). Convection in the central Irminger Sea; insights into variability and the roles of surface forcing and stratification from 19 years of high resolution mooring data
Chapter 3 - Simple feedback explains complex channel patterns in coastal wetlands
No full textSpatial patterns are omnipresent in nature (Rodriguez-Iturbe and Rinaldo, 1997; Kondo, 2002; Meinhardt, 2003; Rietkerk and van de Koppel, 2008; Petit and Anfodillo, 2009) and directly affect the functioning and resilience of the (eco)systems in which they manifest themselves (Rietkerk et al., 2004; van de Koppel et al., 2005; Weerman et al., 2010; Liu et al., 2014b). Scale-dependent feedback, which typically is positive nearby and negative further away, provides a widely accepted explanation for the formation of simple, single-scale patterns (Meinhardt, 2003; Rietkerk and van de Koppel, 2008; Petit and Anfodillo, 2009). However, it is unclear whether the more complex, multi-scale patterns that characterize many natural systems can be explained by equally generic mechanisms. As a model system, we here study the tidal channels that characterize coastal wetlands (Hughes, 2012), as these channels constitute patterns that vary greatly in geometry, ranging from simple parallel channels (Temmerman et al., 2007; Weerman et al., 2010; van de Vijsel et al., 2020) to complexly branching networks (Rodriguez-Iturbe and Rinaldo, 1997; Rinaldo et al., 1999), with direct consequences for the functioning and resilience of valuable wetland ecosystems. We reveal that the broad spectrum of geometries typical for tidal channel patterns can be explained by one scale-dependent feedback. This is a biogeomorphic feedback that roughly follows Turing's activator-inhibitor principle (Rietkerk and van de Koppel, 2008) and results from flow deflection and channel incision around biotically (biofilms, algae, plants) stabilized sediment (Temmerman et al., 2007; Weerman et al., 2010; van de Vijsel et al., 2020). Using a mathematical model, we now show that as the biogeomorphic feedback gets stronger, complex multi-scale patterns emerge due to self-induced recursion of the scale-dependent feedback, which results in nesting of regular channel patterns at successively finer scales. This recursive mechanism provides an explanation for poorly understood geometric properties of real-world tidal networks (Rinaldo et al., 1999). We further find that increased network complexity directly translates to enhanced drainage efficiency, sediment accretion rates and ecosystem productivity. These results highlight the vital importance of network complexity for the functioning of coastal wetlands, ultimately determining their resilience to sea level rise (Kirwan and Megonigal, 2013) and storm surge buffering capacity (Temmerman et al., 2013), and with that their potential to mitigate the effects of global change that threaten densely populated coastal lowlands worldwide
Data from: Prey ingestion rates revealed by back-mounted accelerometers in Eurasian spoonbills
No full textBackground
Quantifying foraging success in space and time and among individuals is essential for answering many
ecological questions and may guide conservation efforts. However, collecting this information is challenging for
species that forage on mobile prey and are difficult to observe visually, for example, because they forage in
inaccessible areas or at night. In such cases, the use of tracking devices that simultaneously collect location and
acceleration data may provide a solution if foraging success can be extracted successfully. The aim of this study
was to assess how well searching for and ingesting prey, among other behaviours, could be distinguished from
20 Hz acceleration data collected by GPS/ACC-trackers mounted on the back of Eurasian spoonbills Platalea
leucorodia. Upon capturing a prey, spoonbills make a distinct movement with their head and back to throw the
prey from the tip of the bill into the throat.
Methods
We compared the behavioural classification performance of random forest models that were trained and tested
on video-annotated acceleration data segments of different (fixed or flexible) lengths. The best-performing
model was then applied to 4 years of data of spoonbills foraging in the Wadden Sea during the breeding
season, to explore seasonal and annual variation in prey ingestion rates.
Results
Highest classification accuracies (as indicated by the F-measure, a balanced measure of precision and
sensitivity) of foraging behaviours were achieved by analysing short fixed-length segments (0.4-0.8 s) or
'flexibly-cut' segments. The F-measure was very high (> 0.90) for searching, standing, sitting and flying
(distinguishing active and passive flight), 0.73 for ingesting prey and 0.65 for walking. False positive and
negative prey ingestions were equally likely and most often confused with searching, resulting in a close match
between the predicted and observed prey ingestion rates. Application of the best-performing model revealed
strong seasonal patterns in prey ingestion rates in the Wadden Sea that varied between years.
Conclusions
We show that prey ingestion rates of Eurasian spoonbills can be fairly accurately estimated from acceleration
data. These results are promising for the use of spoonbills equipped with GPS/ACC-trackers as monitors of
spatial and temporal variation in the availability of small fish and shrimp, which is key to understand their
foraging and migratory movements of spoonbills and provides information on the quality of (coastal) wetlands