Time is an affliction: Why ecology cannot be as predictive as physics and why it needs time series

Ecological systems depend on both constraints and historical contingencies, both of which shape their present observable system state. In contrast to ahistorical systems, which are governed solely by constraints (i.e. laws), historical systems and their dynamics can be understood only if properly described, in the course of time. Describing these dynamics and understanding long-termvariability can be seen as themission of long time series measuring not only simple abiotic features but also complex biological variables, such as species diversity and abundances, allowing deep insights in the functioning of food webs and ecosystems in general. Long timeseries are irreplaceable for understanding change, and crucially inherent system variability and thus envisaging future scenarios. This notwithstanding current policies in funding and evaluating scientific research discourage the maintenance of long term series, despite a clear need for long-term strategies to cope with climate change. Time series are crucial for a pursuit of the much invoked Ecosystem Approach and to the passage from simple monitoring programs of large-scale and long-termEarth observatories — thus promoting a better understanding of the causes and effects of change in ecosystems. The few ongoing long time series in European waters must be integrated and networked so as to facilitate the formation of nodes of a series of observatories which, together, should allowthe long-termmanagement of the features and characteristics of European waters. Human capacity building in this region of expertise and a stronger societal involvement are also urgently needed, since the expertise in recognizing and describing species and therefore recording them reliably in the context of time series is rapidly vanishing from the European Scientific community

Further records of a new diatom species in the English Channel and North Sea: the importance of image-referenced data

Background In September 2015, an at the time undescribed, autotrophic taxon was discovered in the western English Channel (station L4) and also in the eastern English Channel and Celtic Sea during the Polarstern Cruise PS95 a month later. Subsequent investigations revealed further extensive records (going back to 1992) at stations in the English Channel and the southern North Sea (e.g. Helgoland Roads and Sylt Roads time series stations). Stations in the Northern North Sea have not recorded this distinct taxon. With the available records and crucially, the accompanying image metadata, we are able to chart a clear distribution record with occurrences being restricted to the southern North Sea and English Channel. Methods The biological data shown are from Lugol-fixed Utermöhl counts and investigations of live and Formalin-fixed net hauls (20 μm mesh size). All image material shown is available in the online repository Planktonnet (http://planktonnet.awi.de). Results We report the distribution, based on geo-referenced image records of an easily recognisable, yet taxonomically uncertain, autotrophic organism. Conclusions Distribution patterns of the unidentified autotrophic taxon suggests entry of this taxon into/out of the North Sea via the English Channel. Further investigations providing image-documented information over several years is clearly necessary to clarify its dynamics and ecological characteristics

Klimawandel und Plankton

Ein besseres Verständnis der Auswirkungen des Klimawandels auf die marinen Ökosysteme ist für den Menschen sowohl aus ökologischer wie auch ökonomischer Sicht von herausragender Bedeutung. Die Reaktion von Phyto- und Zooplanktern auf klimatische Veränderungen spielt aufgrund ihrer Funktion als Primär- und Sekundärproduzenten im marinen Nahrungsnetz eine zentrale Rolle in diesem Prozess. Die Erwärmung der oberflächennahen Schichten in Ozeanen und Randmeeren hat ökologische Veränderungen in Form von Verschiebungen in den biogeographischen und zeitlichen Verteilungsmustern von planktischen Organismen zur Folge. Indirekte Temperatureffekte können u.a. aus einer verstärkten Stratifizierung, welche den vertikalen Austausch von Nährstoffen und damit ihre Verfügbarkeit für das Phytoplankton in der euphotischen Zone reduziert, resultieren. Unterschiede in der phänologischen Reaktion von Phyto- und Zooplanktern hinsichtlich gestiegener Wassertemperaturen können zur innerjährlichen Entkopplung funktionaler Verbindungen zwischen beiden Gruppen führen, mit Folgen auch für die Nahrungsverfügbarkeit und -qualität von Fischen. Der Anstieg der atmosphärischen Kohlendioxid-Konzentration (CO2) führt zu einer Versauerung der Meere und dadurch zu Veränderungen der chemischen Zusammensetzung des Meerwassers. Eine Abnahme des pH-Wertes hat u.a. potentiell negative Implikationen für kalzifizierende, planktische Organismen. Klimatische Effekte auf marine Ökosysteme können sich lokal und regional unterschiedlich manifestieren und, etwa in Küstenregionen, durch anthropogene Einflüsse (z.B. Nährstoffeinträge) überlagert werden. Biologisch-physikalische gekoppelte Modelle können einen Beitrag liefern, die Auswirkungen klimatischer Änderungen auf marine Ökosysteme besser zu verstehen und potentielle, zukünftige Entwicklungen abzuschätzen

Rapid succession drives spring community dynamics of small protists at Helgoland Roads, North Sea

The dynamics of diatoms and dinoflagellates have been monitored for many decades at the Helgoland Roads Long-Term Ecological Research site and are relatively well understood. In contrast, small-sized eukaryotic microbes and their community changes are still much more elusive, mainly due to their small size and uniform morphology, which makes them difficult to identify microscopically. By using next-generation sequencing, we wanted to shed light on the Helgoland planktonic community dynamics, including nano- and picoplankton, during a spring bloom. We took samples from March to May 2016 and sequenced the V4 region of the 18S rDNA. Our results showed that mixotrophic and heterotrophic taxa were more abundant than autotrophic diatoms. Dinoflagellates dominated the sequence assemblage, and several small-sized eukaryotic microbes like Haptophyta, Choanoflagellata, Marine Stramenopiles and Syndiniales were identified. A diverse background community including taxa from all size classes was present during the whole sampling period. Five phases with several communities were distinguished. The fastest changes in community composition took place in phase 3, while the communities from phases 1 to 5 were more similar to each other despite contrasting environmental conditions. Synergy effects of next-generation sequencing and traditional methods may be exploited in future long-term observations

Ocean Colour remote sensing in the Southern Laptev Sea: evaluation and applications

Enhanced permafrost warming and increased arctic river discharges have heightened concern about the input of terrigeneous matter into Arctic coastal waters. We used optical operational satellite data from the Ocean Colour sensor MERIS onboard the ENVISAT satellite mission for synoptic monitoring of the pathways of terrigeneous matter in the southern Laptev Sea. MERIS satellite data from 2006 on to 2011 were processed using the Case2Regional Processor, C2R, installed in the open-source software ESA BEAM-VISAT. Since optical remote sensing using Ocean Colour satellite data has seen little application in Siberian Arctic coastal and shelf waters, we assess the applicability of the calculated MERIS parameters with surface water sampling data from the Russian-German ship expeditions LENA2010 and TRANSDRIFT-XVII taking place in August and September 2010 in the southern Laptev Sea. The surface waters of the southern Laptev Sea are characterized by low transparencies, due to turbid river water input, terrestrial input by coastal erosion, resuspension events and, therefore, high background concentrations of Suspended Particulate Matter, SPM, and coloured Dissolved Organic Matter, cDOM. The mapped calculated optical water parameters, such as the first attenuation depth, Z90, the attenuation coefficient, k, and Suspended Particulate Matter, SPM, visualize resuspension events that occur in shallow coastal and shelf waters indicating vertical mixing events. The mapped optical water parameters also visualize that the hydrography of the Laptev Sea is dominated by frontal meanders with amplitudes up to 30 km and eddies and filaments with diameters up to 100 km that prevail throughout the ice-free season. The meander crests, filaments and eddy-like structures that become visible through the mapped MERIS C2R parameters indicate enhanced vertical and horizontal transport energy for the transport of terrigenous and living biological matter in the surface waters during the ice-free season

Coordinating sustained coastal and ocean observing efforts in Germany

Germany’s national ocean observing activities are carried out by multiple actors including governmental bodies, research institutions, and universities, and miss central coordination and governance. A particular strategic approach to coordinate and facilitate ocean research has formed in Germany under the umbrella of the German Marine Research Consortium (KDM). KDM aims at bringing together the marine science expertise of its member institutions and collectively presents them to policy makers, research funding organizations, and to the general public. Within KDM, several strategic groups (SGs), composed of national experts, have been established in order to strengthen different scientific and technological aspects of German Marine Research. Here we present the SG for sustained open ocean observing and the SG for sustained coastal observing. The coordination effort of the SG’s include (1) Representing German efforts in ocean observations, providing information about past, ongoing and planned activities and forwarding meta-information to data centers (e.g., JCOMMOPS), (2) Facilitating the integration of national observations into European and international observing programs (e.g. GCOS, GOOS, BluePlanet, GEOSS), (3) Supporting innovation in observing techniques and the development of scientific topics on observing strategies, (4) Developing strategies to expand and optimize national observing systems in consideration of the needs of stakeholders and conventions, (5) Contributing to agenda processes and roadmaps in science strategy and funding, and (6) Compiling recommendations for improved data collection and data handling, to better connect to the global data centers adhering to quality standards

Operating Cabled Underwater Observatories in Rough Shelf-Sea Environments:A Technological Challenge

Cabled coastal observatories are often seen as future-oriented marine technology that enables science to conduct observational and experimental studies under water year-round, independent of physical accessibility to the target area. Additionally, the availability of (unrestricted) electricity and an Internet connection under water allows the operation of complex experimental setups and sensor systems for longer periods of time, thus creating a kind of laboratory beneath the water. After successful operation for several decades in the terrestrial and atmospheric research field, remote controlled observatory technology finally also enables marine scientists to take advantage of the rapidly developing communication technology. The continuous operation of two cabled observatories in the southern North Sea and off the Svalbard coast since 2012 shows that even highly complex sensor systems, such as stereo-optical cameras, video plankton recorders or systems for measuring the marine carbonate system, can be successfully operated remotely year-round facilitating continuous scientific access to areas that are difficult to reach, such as the polar seas or the North Sea. Experience also shows, however, that the challenges of operating a cabled coastal observatory go far beyond the provision of electricity and network connection under water. In this manuscript, the essential developmental stages of the "COSYNA Shallow Water Underwater Node" system are presented, and the difficulties and solutions that have arisen in the course of operation since 2012 are addressed with regard to technical, organizational and scientific aspects.</p

CHARACTERIZATION AND FATE OF DISSOLVED ORGANIC MATTER IN THE LENA DELTA REGION, SIBERIA

Connectivity between the terrestrial and marine environment in the Artic is changing as a result of climate change, influencing both freshwater budgets and the supply of carbon to the sea. This study characterizes the optical properties of dissolved organic matter (DOM) within the Lena Delta region and evaluates the behavior of DOM across the fresh water-marine gradient. Six fluorescent components (four humic-like; one marine humic-like; one protein-like) were identified by Parallel Factor Analysis (PARAFAC) with a clear dominance of allochthonous humic-like signals. Colored DOM (CDOM) and dissolved organic carbon (DOC) were highly correlated and had their distribution coupled with hydrographical conditions. Higher DOM concentration and degree of humification were associated with the low salinity waters of the Lena River. Values decreased towards the higher salinity Laptev Sea shelf waters. Results demonstrate different responses of DOM mixing in relation to the vertical structure of the water column, as reflecting the hydrographical dynamics in the region. Two mixing curves for DOM were apparent. In surface waters above the pycnocline there was a sharper decrease in DOM concentration in relation to salinity indicating removal. In the bottom water layer the DOM decrease within salinity was less. We propose there is a removal of DOM occurring primarily at the surface layer, which is likely driven by photodegradation and flocculation

Coordinating sustained coastal and ocean observing systems in Germany

The strategic approach to coordinate coastal and open ocean observations in Germany is introduced. The German Marine Research Consortium (KDM) aims at bringing together the marine science expertise of its member institutions and collectively presents them to policy makers, research funding organizations, and to the general public. Several strategic groups (SGs), composed by national experts, have been established under the KDM umbrella in order to coordinate scientific and technological aspects of German Marine Research. Two of these groups, namely the SG for sustained ocean observing systems and the SG for coastal observing systems aim at coordinating on a national level the variety of marine observing efforts. The activities of the SGs address technological challenges and solutions for observations, the current and future observing needs and the seamless integration of Germanys observing efforts into the European and global observing initiatives. The presented poster will introduce the members of the working group and their observing systems, as well as the goals of KDM