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INRAE

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Last update: May 2021

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BREKENFELD Nicolai

Brekenfeld-0

Scientist (Post-doc) at SAS

Email: nicolai.brekenfeld@inrae.fr

Address: UMR SAS, 65 rue de St-Brieuc, CS 84215, 35042 Rennes Cedex, France

Fields of expertise: Hydrology and biogeochemistry in headwater catchments, in-stream processes, hyporheic exchange, low-cost sensor development

Keywords: Solute transport in headwater catchments, hydrological fluxes and biogeochemical processes in the hyporheic zone, groundwater – surface-water interactions, stream metabolism, high-frequency solute dynamics, carbon, nutrient

Research

Current Research Topics

My research topics are hydrology and biogeochemistry in headwater catchments and in-stream processes in low-order streams. I am interested in understanding the drivers of hydrological flow path activation and solute transport in contrasting headwater catchments (agricultural, tile-drained, forested). I am using timeseries of high-frequency (< 60 min) chemical data at the catchment outlet, in combination with hydrometric and geochemical data from piezometers and groundwater wells, distributed in the catchment.

I am also interested in bedform driven hyporheic exchange and solute transformation (C, nutrients) at the groundwater – surface-water interface as well as drivers of in-stream metabolism (PhD thesis). I use mulit-level piezometers, tracer injections, isotopic and geochemical signatures as well as self-built low-cost conductance sensors to explore these questions.

Current Projects

National innovative equipment infrastructure for spatial and temporal monitoring of the Critical Zone « CRITEX » (Post-Doc). I am using the high-frequency chemical data collected by the three Riverlabs at the AgrHyS (Naizin), ORACLE (Orgeval), and OHGE (Aubure) observatories, with collaborators at Géosciences Rennes (Rennes), UMR IPGP (Paris), UR HYCAR (Antony) and UMR LYGHES (Strasbourg).

Teaching Experience

Classes about tracer injections (travel time and flow paths) and discharge measurements at the Catchment Science Summer School (coordinated by Dr. Jeff McDonnell).

Publications

Windsor, F. M., Docherty, C. L., Brekenfeld, N., … (2021): Hydrological, physicochemical and metabolic signatures in groundwater and snowmelt streams in the Japanese Alps. Jounal of Hydrology, 600. https://doi.org/10.1016/j.jhydrol.2021.126560

Navratil, O., Brekenfeld, N.,… (2021): Distribution of Asian knotweeds on the Rhône River basin, France: A multi-scale model of invasibility that combines biophysical and anthropogenic factors. Science of The Total Environment, 763. https://doi.org/10.1016/j.scitotenv.2020.142995

MacKenzie, A. R., …, Brekenfeld, N., … (2021): BIFoR FACE: Water–soil–vegetation–atmosphere data from a temperate deciduous forest catchment, including under elevated CO2. Hydrological Processes, 35 (3). https://doi.org/10.1002/hyp.14096

Comer-Warner, S. A., Blaen, P. J., Brekenfeld, N., … (2021): Advection Not Dispersion and Transient Storage Controls Streambed Nutrient and Greenhouse Gas Concentrations. Frontiers in Water. https://doi.org/10.3389/frwa.2021.668183

Ward, A. S., Zarnetske, J. P., Baranov, V., Blaen, P. J., Brekenfeld, N.,… (2019): Co-located contemporaneous mapping of morphological, hydrological, chemical, and biological conditions in a 5th-order mountain stream network, Oregon, USA. Earth Syst. Sci. Data, 11, 1567–1581. https://doi.org/10.5194/essd-11-1567-2019

Ward, A., S., …, Brekenfeld, N., … (2019): Spatial and temporal variation in river corridor exchange across a 5th-order mountain stream network. Hydrol. Earth Syst. Sci., 23, 5199–5225. https://doi.org/10.5194/hess-23-5199-2019

Blaen, J. P., Brekenfeld, N. (shared first author), Comer-Warner, S., Krause, S. (2017): Multitracer Field Fluorometry: Accounting for Temperature and Turbidity Variability During Stream Tracer Tests. Water Resources Research, 53 (11), 9118-9126. https://doi.org/10.1002/2017WR020815