Lukas Kohl

I'm a biogeochemist broadly interested bridging the gap in our understanding of microbial processes and of ecosystem ecology / organic geochemistry. This is challenging because it requires linking systems of highly divergent scales in space (microscopic scale to ecosystem scale) and time (processes variable in hours to days affect stocks with turnover times of decades to millenia). I’m further interested in how human activity (e.g. elevated temperature, CO2 concentration, nutrient inputs, and contaminant imissions) affect the working of natural ecosystems and their feedback on the Earth System and ultimately human society. Finally, I’m interested in how microorganisms adapt to extreme habitats and in turn change their (chemical) environment in these habitats.

My research is based on chemical and isotopic techniques. In particular, I currently work with compound specific isotopic analysis in microbial lipids, trace gases, and volatile organic acids as well as a range of chemical analysis in solid, liquid, and gaseous samples. My work has a strong methodological focus and I’m always interested in critically evaluating current methods, and developing new methods and applications. Furthermore, my work often combines such techniques with data generated by genomic and/or proteomic methods.

I received a technical training as a (bio-)analytical chemist and then studied biology and molecular biology at the University of Vienna. In my MSc. thesis, I explored how litter nutrient content affects the changes in litter chemistry during and 15-month litter decomposition experiment. This work also included taking an pyrolysis-GC/MS unit into operation, establishing routines for sample analysis and data interpretation, as well as general instrument maintenance.

I’m currently a PhD candidate at Memorial University supervised by Sue Ziegler and Penny Morrill (expected completion Summer 2016). With Sue, I explore how the δ13C of fungi, bacteria, and total biomass varies within soil profiles and along a latitudinal transect (link to NL-BELT). I’m currently working on demonstrating that these isotopic signatures can be used to demonstrate where, why, and how differences in microbial activity lead to the accumulation of soil organic matter with different properties (biodegradeability, temperature sensitivity). Beside my work with boreal forest soil, I study microbial processes (CO oxidation and fixation, methanogenesis, acetogenesis) in ultra-basic, reducing springs at two sites of present-day serpentinization (The Tablelands, NL, Canada and The Cedars, CA, US) with Penny Morrill.

You can reach me via email at: lukas.kohl@mun.ca

Publications:

Kohl, L. Laganière, J., Edwards, K., Billings, S.A, VanBiesen,G., Morrill, P.L, and S.E. Ziegler (2015) Distinct fungal and bacterial δ13C signatures as potential drivers of increasing δ13C of soil organic matter with depth. Biogeochemistry Letters 124:13-26.

Morrill, P.A., Brazelton, W., Kohl, L., Rietze, A., Miles, S., Kavanagh, H., Schrenk, M., Ziegler, S.E., and S. Lang (2014) Investigations of potential microbial methanogenic and carbon monoxide utilization pathways in ultra-basic reducing springs associated with present day continental serpentinization: The Tablelands, NL, CAN. Frontiers in Microbiology 5: 613.

 

Contact

Earth Sciences

230 Elizabeth Ave

St. John's, NL A1B 3X9 CANADA

Tel: (709) 864-2530

Fax: (709) 864-2552

becomestudent@mun.ca