Publications
Following publications have been announced by our department Biological Carbon Pump. For further information please contact the marked authors of the publications:
Kordubel, K., Baschek, B., Hieronymi, M., Voynova, Y.G., & Möller, K.O. (2024): Improving the sampling of red Noctiluca scintillans to understand its impact on coastal ecosystem dynamics. Journal of Plankton Research, doi:10.1093/plankt/fbae010
Abstract:
Recently, natural and anthropogenic pressures caused an apparent increase in the frequency and spread of red Noctiluca scintillans (RNS) blooms. Here, we describe this potential expansion and the associated environmental factors based on an extensive literature review (1857–2023). Our analysis suggests that Noctiluca increased over time in several Australian, Chinese and European coastal regions. We point to eutrophication, ocean warming and deoxygenation as possible drivers of these intensifications. Moreover, we demonstrate Noctiluca’s importance for coastal ecosystems: with competitive advantages causing fast and intense blooms, Noctiluca has the potential to alter plankton communities, influencing productivity in affected areas. Throughout our analysis, we identified major knowledge gaps that are relevant to assess Noctiluca: (i) challenges in determining its spatiotemporal evolution; (ii) limited knowledge about drivers triggering and ending blooms; (iii) scarce information about feeding, reproduction and interaction in situ and (iv) uncertainty regarding its contribution to carbon export. We hypothesize that these gaps are related to limitations in traditional sampling techniques, and we highlight the need for a holistic approach combining traditional with novel techniques like remote sensing and underwater cameras. Our suggested approach could help filling the identified gaps and facilitate predictions of bloom dynamics and impacts under future climate conditions.
Rühl, S., & Möller, K.O. (2024): Storm events alter marine snow fluxes in stratified marine environments. Estuarine, Coastal and Shelf Science, 108767, doi:10.1016/j.ecss.2024.108767
Abstract:
Marine snow is an important part of the biological pump and marine food web, and although previous research has provided a thorough understanding of the underlying mechanisms of marine snow dynamics in general, there is still a knowledge gap concerning extreme conditions, such as storm events. Storms are predicted to increase in magnitude and frequency in the future, and could potentially have a large impact on marine snow dynamics. For these reasons, we assessed the effects of storm events on marine snow dynamics in the Baltic Sea, an area chosen due to its well-studied and stable stratified conditions outside of meteorologically extreme events. The combination of in-situ imaging and biogeochemical environmental data from three different years facilitates an assessment of storm event impacts, while simultaneously excluding the possibility that patterns in particle distribution and abundances were due to other environmental influences. The results show that extreme meteorological events such as storms can increase the abundance of marine snow in stratified marine environments by a factor of 10 or more. The particles are distributed more widely and are larger, brighter, rounder and less complexly shaped. In non-extreme conditions, particles have been observed to deposit along the density gradients in thin-layer aggregations. This study indicates that storms can episodically disrupt these formations, thereby altering vertical flux and export potentials across stratification boundaries. In addition, we observed that marine snow abundances are drastically higher in the aftermath of storm events than under calm conditions, potentially due to the disaggregation of larger particles and lateral import of resuspended matter from shallower areas. In light of the increased frequency and magnitude of storms in the future due to climate change, our findings indicate that marine snow dynamics in stratified environments might be altered permanently.
