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Sediment reworking by benthic infauna, namely bioturbation, is of pivotal importance in expansive soft-sediment environments such as the Wadden Sea. Bioturbating fauna facilitate ecosystem functions such as bentho-pelagic coupling and sediment nutrient remineralization capacities. Yet, these benthic fauna are expected to be profoundly affected by current observed rising sea temperatures. In order to predict future changes in ecosystem functioning in soft-sediment environments like the Wadden Sea, knowledge on the underlying processes such as sediment reworking, is crucial. Here, we tested how temperature affects bioturbation and its associated ecosystem processes, such as benthic nutrient fluxes and sediment oxygen consumption, using luminophore tracers and sediment incubation cores. We used a controlled mesocosm experiment set-up with key Wadden Sea benthos species: the burrowing polychaetes Arenicola marina and Hediste diversicolor, the bivalve Cerastoderma edule, and the tube-building polychaete Lanice conchilega. The highest bioturbation rates were observed from A. marina, reaching up to 375 cm2yr−1; followed by H. diversicolor, with 124 cm2yr−1 being the peak bioturbation rate for the ragworm. Additionally, the sediment reworking activity of A. marina facilitated nearly double the amount of silicate efflux compared to any other species. Arenicola marina and H. diversicolor accordingly facilitated stronger nutrient effluxes under a warmer temperature than L. conchilega and C. edule. The oxygen uptake of A. marina and H. diversicolor within the sediment incubation cores was correspondingly enhanced with a higher temperature. Thus, increases in sea temperatures may initially be beneficial to ecosystem functioning in the Wadden Sea as faunal bioturbation is definitely expedited, leading to a tighter coupling between the sediment and overlying water column. The enhanced bioturbation activity, oxygen consumption, and facilitated nutrient effluxes from these invertebr

10th International Crustacean Congress

In times of rapidly increasing multiple anthropogenic impacts on polar marine ecosystems and biodiversity, understanding, sustainable-use management and protection of these biotas is a matter of great concern. Research on marine biotas and their interactions with each other and the environment is fundamental in that regard, but available data are still diverse and scattered, as they exist in many formats and sources, such as published literature, data repositories, and unpublished material. Due to this heterogeneity, information is difficult to find, access and combine, severely impeding its reuse for further scientific analysis and its long-term availability for future generations. Scientists, decision makers, and the public require a versatile tool to compile, synthesize and manage biodiversity data in a transparent, efficient and comprehensible way and with high-level quality assurance. To address this challenge, we developed, implemented and utilize CRITTERBASE (https://critterbase.awi.de), a publicly accessible data warehouse and interactive portal that complies with the FAIR principles (Findability, Accessibility, Interoperability and Reusability of data). Its purpose is to complement long-term data storage repositories by providing powerful but easy-to-use data ingest, retrieval and exploration tools, thus facilitating the analysis of biodiversity data across multiple spatial and temporal scales and in wider contexts. Currently, it hosts quality-controlled and taxonomically standardized presence/absence, abundance, and biomass data from Arctic, North Sea and Antarctic regions, collated from the literature, unpublished data, own research and online repositories (with all metadata and links to primary sources included), for 3,173 polar benthic taxa (2,444 of which at species level) from 12,209 samples collected with grabs, underwater imaging or trawls between 1800 and 2014. CRITTERBASE is currently holding benthic biodiversity data only but because of its compr

Low-frequency noise (LFN), or sound waves with frequencies between 10 Hz to 500 Hz, has increased substantially in coastal and shelf waters over the last decades. This is in large part due to the escalation in human activities such as shipping, wind farming, and pile-driving. Concern over how LFN affects marine mammal and fish welfare (eg. foraging efficiency, acoustic communication interference) has led the European Marine Strategy Framework Direction to include noise as a descriptor for achieving “good” environmental status. While the effects of anthropogenic noise on marine mammals and fish are by no means well documented, the effects of such noise on marine benthic invertebrates, crucial ecosystem engineers that continually rework sediment, are even less understood. Here, we present how LFN affects the behavior and sediment reworking activities of select macrobenthic invertebrate species from the North Atlantic in controlled laboratory setups. The polychaete Lanice conchilega, an abundant benthic invertebrate, exhibited behavioral responses to LFN in the form of modified pumping behavior. The amphipod crustacean Corophium volutator was negatively affected by LFN, exhibiting lower bioturbation rates and shallower burial depths compared to controls. The effect of LFN on the polychaete Arenicola marina and the bivalve Limecola balthica remained inconclusive, though A. marina displayed greater variability in bioirrigation rates when exposed to LFN. Benthic macroinvertebrates may be in jeopardy alone with the crucial ecosystem-maintaining services they provide, thus more research is urgently needed to understand, predict, and manage the impacts of anthropogenic noise pollution on marine fauna and their associated ecosystems.