EESS talk on "Coral Biophotonics and Microscale Canopy Effects"
Event details
| Date | 19.03.2019 |
| Hour | 12:15 › 13:00 |
| Speaker | Dr Michael Kühl, Professor, Microenvironmental Ecology, Dept. of Biology, University of Copenhagen (DK) and Climate Change Cluster, University of Technology Sydney (AU) is trained in marine biology and microbial ecology but have broad interdisciplinary interests ranging from technicalities of sensor development, over a fascination of single cell microbiology and behaviour, to studies of microenvironmental controls and microbial interactions in aquatic communities and ecosystems, but also in medical biofilms and chronic infections. Michael Kühl enjoyd working at the boundaries and interfaces of different scientific disciplines and implement sensor chemistry, photonics, 3D bioprinting and advanced imaging approaches in his research. His research interests include: Microenvironmental ecology of surface-associated microbial communities, aquatic plants and marine symbioses; Microsensor and imaging techniques for biogeochemical analysis of microenvironments, mass transfer and metabolic rates; Optical properties and photobiology of sediments, photosynthetic tissues and biofilms; Microbial behaviour and activity in gradient systems. Graduated from University of Aarhus (1992), M. Kühl founded and headed the Microsensor Research Group at the Max-Planck-Institute for Marine Microbiology (1992-1998), and is leading the Microenvironmental Ecology Group at University of Copenhagen (1998-present), where he holds a professorship in aquatic microbial ecology. He is also an adjunct professor at University of Technology Sydney (since 2010) and has been a vising professor at the Singapore Centre for Environmental Life Sciences Engineering at the Nanyang Technological University (2011-2015). |
| Location | |
| Category | Conferences - Seminars |
Abstract:
Surface-associated assemblages of oxygenic microbial phototrophs (microalgae and cyanobacteria) in biofilms and photosymbioses are characterized by a high optical density and (sub-)mm-thick photic zones, wherein steep and dynamic gradients of light, temperature, pH, O2 and other chemical species modulate photosynthetic performance. While application of various microscale methods has given detailed insight to photosynthesis in such gradient environments, links between the optical properties and structural complexity of such assemblages remain largely unstudied. My group has employed microsensors and novel imaging techniques to explore structure-function relationships and photosynthetic quantum efficiency in biofilms, sediments and corals. In this seminar, I present a new conceptual view of how light harvesting is balanced against light protection in corals, enabling optimization of the photosynthetic performance of their microalgal symbionts under a wide range of optical niches. Based on recent studies of the coral microenvironment, I argue that high photosynthetic efficiency in corals is largely modulated by the microscale optical properties and three-dimensional structure of coral tissue distribution over the underlying skeleton. Such links between coral function and morphology can be understood in the framework of canopy effects, in analogy to the function of plant canopies (albeit at much larger scales), enabling efficient and flexible light harvesting. I review the current evidence for how corals modulate their light microenvironment. This includes recent findings about scattering and light propagation in coral tissue and skeleton that together with tissue plasticity (expansion/contraction) can explain the high efficiency of coral photosynthesis. I also briefly discuss the relevance of these findings for our understanding of other compact photosynthetic structures like biofilms and microbial mats.
Surface-associated assemblages of oxygenic microbial phototrophs (microalgae and cyanobacteria) in biofilms and photosymbioses are characterized by a high optical density and (sub-)mm-thick photic zones, wherein steep and dynamic gradients of light, temperature, pH, O2 and other chemical species modulate photosynthetic performance. While application of various microscale methods has given detailed insight to photosynthesis in such gradient environments, links between the optical properties and structural complexity of such assemblages remain largely unstudied. My group has employed microsensors and novel imaging techniques to explore structure-function relationships and photosynthetic quantum efficiency in biofilms, sediments and corals. In this seminar, I present a new conceptual view of how light harvesting is balanced against light protection in corals, enabling optimization of the photosynthetic performance of their microalgal symbionts under a wide range of optical niches. Based on recent studies of the coral microenvironment, I argue that high photosynthetic efficiency in corals is largely modulated by the microscale optical properties and three-dimensional structure of coral tissue distribution over the underlying skeleton. Such links between coral function and morphology can be understood in the framework of canopy effects, in analogy to the function of plant canopies (albeit at much larger scales), enabling efficient and flexible light harvesting. I review the current evidence for how corals modulate their light microenvironment. This includes recent findings about scattering and light propagation in coral tissue and skeleton that together with tissue plasticity (expansion/contraction) can explain the high efficiency of coral photosynthesis. I also briefly discuss the relevance of these findings for our understanding of other compact photosynthetic structures like biofilms and microbial mats.
Practical information
- General public
- Free
- This event is internal
Organizer
- EESS - IIE
Contact
- Prof. Tom I. Battin, SBER