Staff

Dr. Marlene Wall
Research devision 3: Marine Ecology
Research Unit: Experimental Benthic Ecology
Büro:
Room: HB-110
Phone: +49 431 600-4084
e-Mail: mwall(at)geomar.de
Address:
Hohenbergstraße 2
D-24105 Kiel
Current research focus
My current research focuses on the role of natural environmental variability and how it can provide refugia under environmental stress conditions, protects organisms from severe damage and renders them more resilient to future climate changes.
I address this by studying:
a) Baltic sea calcifying epibionts that live in the diffusive boundary layer of macroalgae that on the one hand exposes them to strong diurnal environmental fluctuations but on the other might provide temporal refugia from ocean acidification as well as seasonal hypoxia,
b) Baltic sea ecosystem engineer Fucus sp. and how the succession of natural phenomena like heat waves and deep water upwelling interactively affects the well-being of different life stages and thus their persistence in a future changing ocean and
c) Coral reefs in the Andaman Sea where large amplitude internal waves protected corals during a severe bleaching event (e.g. Wall et al. 2015, ProcRoySocB, Schmidt, Wall, et al 2016, Coral Reefs) and rendered them resilient to thermal stress (Buerger, Schmidt, Wall, et al. 2016, JEMBE). The aim is to evaluate the potentials of incorporating this understanding as well as adapted coral populations into current reef restoration efforts.
The overall aim is to better characterize natural environmental fluctuations, understand how they affect and change the organisms’ stress response and whether it can train them for climate change. For improved ecosystem management in times of climate change, it is essential to understand organisms’ physiological acclimation capabilities, the potential to adapt as well as identify natural locations that provide refugia. Altogether will shape future biodiversity. We also need to adapt this understanding to different local environmental conditions and incorporate it in current ecosystem restoration activities.
Research approaches
I take advantage of natural marginal conditions (eg. exposure to LAIW, natural pCO2 gradients) and use them as natural laboratories to investigate physiological and ecological changes. I study environmental fluctuations from the microscale within an organisms' diffusive boundary layer using microsensors to the macroscale by environmental monitoring probes and devices (WTW probes, CTD, ADCP, etc), combine it with ecophysiological investigations as well as evaluation of ecosystem conditions. I also work interdisciplinary and apply geochemical tools to decipher physiological adjustments under present day environmental conditions but also to deduce physiological acclimations throughout their past.
Studies / CV
2019 - Research Scientist, GEOMAR; Can we breed heat resistant corals for reef restoration?, funded by the VW-Stiftung Experiment
2016 - 2019 Research Scientist, GEOMAR; Exploring functional interfaces: extreme biogenic fluctuations may amplify or buffer environmental stress on organisms associated with marine macrophytes, funded by the German Science Foundation (DFG), SA 2791/3-1
09/16 - 03/17 Maternity leave
2016-2017: Principal investigator of the Future Ocean Cluster Proposal: Can assisted evolution help protect heat-wave damaged coral reefs?
2015-2016: FWF-SchrödingerPost-doctoral fellow between: GEOMAR, MPI, Bremen and University of Vienna, Austria; pH up-regulation in tropical corals: a key mechanism? Implications for the future and the past.
2012-2015: Post-doctoral scientist, GEOMAR, within the BMBF “Verbundprojekt” BIOACID (Biological Impact of Ocean Acidification, www.bioacid.de) - Consortium 3: Natural CO2 rich reefs - Workpackage 3.5: Structural and chemical changes on the biogenic carbonates under naturally occurring exposure to high pCO2
2009-2012: PhD candidate at the University of Bremen, Bremen and Alfred-Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany. (EU-FP 7 ITN Project CalMarO (Calcification by marine organisms, www.calmaro.eu)); Dissertation: Coral reef growth across scales – from reef framework to skeletal microstructure
2004-2008: MSc Ecology, University of Vienna, Vienna, Austria; Diploma Thesis: Patterns of movement between corals in coral-associated fish Gobiodon histrio: an experimental approach
Publications
16. Johnston MJ, Hennigs LM, Sawall Y, Pansch C*, Wall M* (accepted) Growth response of calcifying marine epibionts to biogenic pH fluctuations and global ocean acidification scenarios. Limnology and Oceanography
15. Feng EY, Sawall Y, Wall M, Lebrato M, Fu Y (accepted) Mitigating coral bleaching with artificial upwelling -a modelling investigation. Frontiers in Marine Science
14. Sawall Y, Harris M, Lebrato M, Wall M, Feng EY (2020) Discrete pulses of cooler deep water can decelerate coral bleaching during thermal stress: Implications for artificial upwelling during heat stress events. Frontiers in Marine Science, doi.org/10.3389/fmars.2020.00720
13. Rashid R, Eisenhauer A, Liebetrau V, Fietzke J, Böhm F, Wall M, Krause S, Rüggeberg A, Dullo W-C, Jurikova H, Samankassou E, Boaz L (2020) Early diagenetic imprint on temperature proxies in Holocene corals: A case study from French Polynesia. Frontiers of Earth Science,doi.org/10.3389/feart.2020.00301
12. Melzner F, Buchholz B, Wolf F, Panknin U, Wall M (2020) Ocean winter warming induced starvation of predator and prey. Proceedings of the Royal Society - Biological Sciences, 287, 20200970
11. Franke A, Blenckner T, Duarte CM, Ott K, Fleming LE, Antia A, Reusch TBH, Bertram C, Hein J, Kronfeld-Goharani U, Dierking J, Kuhn A, Sato C, Van Doorn E, Wall M, Schartau M, Karez R, Crowder L, Keller D, Engel A, Hentschel U, Prigge E (2020) Operationalizing Ocean Health : Toward Integrated Research on Ocean Health and Recovery to Achieve Ocean Sustainability. OneEarth,doi.org/10.1016/j.oneear.2020.05.013.
10. Wall M*, Prada F*, Fietzke J, Caroselli E, Dubinsky Z, Brizi L, Fantazzini P, Franzellitti S, Mass T, Montagna P, Falini G, Goffredo S (2019) Linking internal carbonate chemistry regulation and calcification in corlas growing at a Mediterranean CO2 vent. Frontiers in Marine Science, doi: 10.3389/fmars.2019.0069.
9. Wall M, Crook ED, Fietzke J, Paytan A (2019) Using B isotopes and B/Ca in corals from low saturation springs to constrain calcification mechanisms. Nature Communication, doi: 10.1038/s41467-019-11519-9.
8. Wall M, Fietzke J, Schmidt GM,Fink A, Hofmann LC, de Beer D, Fabricius KE (2016) Internal pH regulation facilitates in situ long-term acclimation of massive corals to end-of-century carbon dioxid conditions. Scientific Reports, doi:10.1038/srep30688.
7. Schmidt GM, Wall M, Taylor M, Jantzen C, Richter C (2016) Large-amplitude internal waves sustain coral health during thermal stress. Coral Reefs, doi: 10.1007/s00338-016-1450-z.
6. Wall M, Ragazzola F, Foster L, Form A, Schmidt D (2015) pH up-regulation as potential mechanism for the cold-water coral Lophelia pertusa to sustain growth in aragonite undersaturated conditions. Biogeosciences, 12, 6869-6880.
5. Buerger P, Schmidt GM, Wall M, Held C, Richter C (2015) Temperature tolerance of the coral Porites lutea exposed to simulated large-amplitude internal waves. Journal of Experimental Marine Biology and Ecololgy, 471, 232-239
4. Wall M, Putchim L, Schmidt GM, Jantzen C, Phongsuwan N, Khokiattiwong S, Richter C (2015) Large-amplitude internal waves benefit corals during heat stress. Proceedings of the Royal Society - Biological Sciences, 282: 20-28.
3. Wall M, Nehrke G (2012) Reconstructing skeletal fiber arrangement and growth mode in the coral Porites lutea (Cnidaria, Scleractinia): A confocal Raman microscopy study. Biogeosciences, 9: 4885-4895.
2. Wall M, Schmidt GM, Janjang P, Khokiattiwong S, Richter C (2012) Differential impact of monsoon and large amplitude internal waves on coral reef development in the Andaman Sea. PLOS ONE, 7 (11): e50207.
1. Wall M, Herler J (2009) Postsettlement movement patterns and homing in a coral-associated fish. Journal of Behavioural Ecology, 20 (1): 87-95.
*shared first/last authorship
Fieldtrips and Cruises
2015 Fieldwork at the Australian Institute of Marine Science (AIMS) - National Sea Simulator. Studying physiological and geochemical response to ocean acidification using microsensors and skeletal geochemical proxies
2014/2013 Fieldtrip to the Papua New Guineas CO2 seeps: Main aim to investigate the coral acclimation potential to ocean acidification along a natural CO2 gradient by combining ecophysiological and geochemical approaches
2011-2009 Fieldtrips from Phuket to several Andaman Sea off-shore islands, Thailand. Chasing large amplitude internal waves along the entire Thai Andaman Sea coast, record their intensity and frequency within shallow reef areas and investigate their effect on coral reef development as well as on coral health during severe heat stress.
2007 Fieldtrip to Dahab, Egypt. Study the behavioural ecology of coral-associated fishes and how it limits their ability to deal with reef degradation.
Public Outreach
Geomar Open Day 2019 - Public presentation on "Coral reefs in a changing climate - endangered ecosystem engineers".
CineMare Int'l Ocean Film Festival Kiel 2018 - Invited guest after the movie screening "Wonders of the Sea" from Jean-Michel Cousteau for schools to discuss with the pupils about the conditions and futures of marine ecosystems.
CineMare Int'l Ocean Film Festival Kiel 2017 - Invited guest after the movie screening "Chasing Coral" from Jeff Orlowski to discuss the film, coral reef research and the future of coral reefs
Kieler Woche 2018 public presentation in course of the "Third International Year of the Reef - IYOR2018" - Titel: Korallenriffe im Klimawandel: Bedrohte Baumeister der Meere
Gallery
Using microsensors to study animal physiology and diffusive boundary layer characteristics:
Experimental approaches