CLIMATE AND EARTH
SYSTEM SCIENCES
Photo: UHH/Denstorf
12 December 2022
Photo: private
His thesis, "Electrical Conductivity as proxy for Enhanced Weathering" was supervised by Prof. Dr. Jens Hartmann (Universität Hamburg) and Dr. Joscha Becker (Universität Hamburg).
Lukas' work focused on the reliable quantification of carbon dioxide (CO2) removal as it is a crucial building block for negative emission technologies. Reliable quantification of enhanced weathering in soils can facilitate a CO2 certificate trading scheme. However, measuring CO2 removal through enhanced weathering in soils is more complex than technological approaches like Direct Air Capture (DAC). In this master thesis, Lukas assessed the reliability of using the bulk soil's Electrical Conductivity (EC) as a proxy for alkalinity in soil water and, therefore, the inorganic CO2 removal. EC sensors are cheap, and EC measurements are not labour-intensive, making them an attractive approach compared to direct soil and water sampling methods. He did laboratory experiments with three different soils from Germany to test his hypothesis. The investigations revealed that Cation Exchange Capacity (CEC) is one of the most important soil properties to consider for Enhanced Weathering in soils. CEC is mainly driven by organic matter and clay content, making these two soil properties essential for the chemical reactions in the soil and, therefore, the observed bulk electrical conductivity signal.
Lukas' future plans?
After finishing his thesis, Lukas will continue working on Enhanced Weathering in the BAM! Project as a PhD student.