Research Topics
Learn more about our current research projects on ResearchGate
Carbon cycling and greenhouse gas dynamics
Inland waters play an important role in the global carbon cycle and emit significant amounts of carbon dioxide and methane to the atmosphere. In streams, rivers, ponds, lakes and reservoirs, we study the importance of the prevailing physical conditions on greenhouse gas production and emission rates. With globally distributed measurements, we are particularly interested in how carbon cycling in aquatic systems is affected by human alterations of inland waters and their catchments,
Interactive documentary: Treibhausgas am Wasserstau
Youtube Video: Methanemissionen aus Flussstauhaltungen
Selected Publications:
- Liu, L., T. De Kock, J. Wilkinson, V. Cnudde, S. Xiao, C. Buchmann, D. Uteau, S. Peth, and A. Lorke. 2018. Methane Bubble Growth and Migration in Aquatic Sediments Observed by X-ray μCT. Environ. Sci. Technol. 52: 2007–2015.
- Magin, K., C. Somlai-Haase, R. B. Schäfer, and A. Lorke. 2017. Regional-scale lateral carbon transport and CO2 evasion in temperate stream catchments. Biogeosciences 14: 5003-5014.
- Alshboul, Z., J. Encinas-Fernández, H. Hofmann, and A. Lorke. 2016. Export of Dissolved Methane and Carbon Dioxide with Effluents from Municipal Wastewater Treatment Plants. Environ. Sci. Technol. 50: 5555–5563.
- Wilkinson, J., A. Maeck, Z. Alshboul, and A. Lorke. 2015. Continuous Seasonal River Ebullition Measurements Linked to Sediment Methane Formation. Environ. Sci. Technol. 49: 13121–13129.
- Maeck, A., T. DelSontro, D. F. McGinnis, H. Fischer, S. Flury, M. Schmidt, P. Fietzek, and A. Lorke. 2013. Sediment trapping by dams creates methane emission hotspots. Environ. Sci. Technol. 47: 8130–8137.
- Maeck, A., H. Hofmann, and A. Lorke. 2014. Pumping methane out of aquatic sediments – ebullition forcing mechanisms in an impounded river. Biogeosciences 11: 2925-2938.
Physical Limnology and Water-Atmosphere Exchange
Flow, turbulence and turbulent mixing are among the most important physical characteristics of aquatic ecosystems. We study how water flow is generated and how it interacts with the atmosphere, with sediments and biota in lakes, reservoirs and rivers.
Selected Publications:
- Noss, C., J. Wilkinson, and A. Lorke. 2018. Triangulation hand-held laser-scanning (TriHaLaS) for micro-and meso-habitat surveys in streams. Earth Surface Processes and Landforms: n/a-n/a.
- Weck, J., and A. Lorke. 2017. Mixing efficiency in the thermocline of lakes observed from eddy correlation flux measurements. J. Geophys. Res.-Oceans 122: 291–305.
- Risse-Buhl, U., C. Anlanger, K. Kalla, T. R. Neu, C. Noss, A. Lorke, and M. Weitere. 2017. The role of hydrodynamics in shaping the composition and architecture of epilithic biofilms in fluvial ecosystems. Wat.Res. 127: 211-222.
- Kreling, J., J. Bravidor, C. Engelhardt, M. Hupfer, M. Koschorreck, and A. Lorke. 2017. The importance of physical transport and oxygen consumption for the development of a metalimnetic oxygen minimum in a lake. Limnol. Oceanogr. 62: 348–363.
- Murniati, E., D. Gross, H. Herlina, K. Hancke, and A. Lorke. 2017. Effects of bioirrigation on the spatial and temporal dynamics of oxygen above the sediment–water interface. Freshwater Science 36: 784-795.
- Noss, C., and A. Lorke. 2016. Roughness, resistance, and dispersion: Relationships in small streams. Water Resour. Res. 52: 2802–2821.
- Hölker, F. and others 2015. Tube-dwelling invertebrates: tiny ecosystem engineers have large effects in lake ecosystems. Ecol. Monographs 85: 333-351.
Water Quality and Global Change 
Inland water are globally affected by human activities: More than 1 Mio dams have been constructed worldwide, river and stream flow is regulated and while water is increasingly abstracted from rivers and lakes, its nutrient and pollutant loads have been increasing. At the same time, inland waters seem to respond faster to climate change than terrestrial systems with more rapid warming observed worldwide.
We study how physical processes in aquatic ecosystems affects key water quality parameters and how they are affected by climate change and human alterations.
Selected Publications:
- Murniati, E., D. Gross, H. Herlina, K. Hancke, and A. Lorke. 2017. Effects of bioirrigation on the spatial and temporal dynamics of oxygen above the sediment–water interface. Freshwater Science 36: 784-795.
- Schulz, R. and others 2015. Review on environmental alterations propagating from aquatic to terrestrial ecosystems. Sci Total Environ. 538: 246-261.
- Maeck, A., and A. Lorke. 2014. Ship-lock induced surges in an impounded river and their impact on sub-daily flow velocity variation. River Research and Applications 30: 494–507.
- Maeck, A., T. DelSontro, D. F. McGinnis, H. Fischer, S. Flury, M. Schmidt, P. Fietzek, and A. Lorke. 2013. Sediment trapping by dams creates methane emission hotspots. Environ. Sci. Technol. 47: 8130–8137.
- Noss, C., A. Dabrunz, R. R. Rosenfeldt, A. Lorke, and R. Schulz. 2013. Three-Dimensional Analysis of the Swimming Behavior of Daphnia magna Exposed to Nanosized Titanium Dioxide. PLoS One 8: e80960.
- Lorke, A., D. F. McGinnis, A. Maeck, and H. Fischer. 2012. Effect of ship locking on sediment oxygen uptake in impounded rivers. Water Resour. Res. 48: W12514.
Flow intermittence and sediment transport as drivers of Nitrogen and Carbon Biogeochemistry
Streams and rivers are highly dynamic ecosystems that undergo cycles of expansion and contraction of their aquatic boundaries related to their flow regime. As a result, there are areas of the streambed that experience flow intermittence and drying. These areas have long been considered inert, yet recent research has shown that they can be biogeochemical hot moments upon flow resumption; what often implies sediment transport. The major objective of this project is the mechanistic understanding of the modulation of streambed biogeochemistry (C-metabolism and N-uptake) by flow resumption. The focus will be on the coupling of flow resumption with sediment transport regarding the variability of both processes so far overlooked.
- 2021). Overlooked implication of sediment transport at low flow: Migrating ripples modulate streambed photo‐ and heterotrophic microbial activity. Water Resources Research, 57, e2020WR027988. https://doi.org/10.1029/2020WR027988 , , , & (
- Schreckinger, J., Mutz, M., Mendoza-Lera, C., & Frossard, A. (2021). Attributes of drying define the structure and functioning of microbial communities in temperate riverbed sediment. Frontiers in Microbiology, 10.3389/fmicb.2021.676615
- Gómez-Gener, Ll.,...Mendoza-Lera, C.,...et al. (2021). Towards an improved understanding of biogeochemical processes across surface-groundwater interactions in intermittent rivers and ephemeral streams. Earth Science Reviews. https://doi.org/10.1016/j.earscirev.2021.103724