Dr. Jeroen H. T. Zethof
E-Mail: jeroen.zethof@rptu.de
Research interest
- Biogeochemical cycles
- Land use change effect on soil properties
- Soil-Plant-Water-Microbial interactions
EJP - C-arouNd
Refining soil conservation and generative practices to improve carbon sequestration and reduce greenhouse gas emissions.
Funding: German Federal Ministry of Education and Research
Researcher: Johanna Maria Zenner, Prof. Dr. Hermann Jungkunst, Dr. Klaus Schützenmeister, Dr. Jeroen Zethof, Dr. Tatiana Rittl
Website: https://ejp-c-around.my.canva.site/
Interested in a bachelor or master thesis?
At the moment there are two open thesis projects:
1) Effect of digested and undigested manure on the vulnerability of organic carbon to decomposition
Carbon stored in soils is the major carbon stock on earth. Common agricultural practices often increase decomposition of this huge carbon storage, resulting in a release of CO2 and CH4 to the atmosphere. In order to reduce such emission, different types of land managements are studied to find the best practice.
As part of C-arouNd project, we study the carbon and nitrogen cycles at an organic farm in Tingvoll (Norway). Grass-clover leys are used to grow fodder for the farm animals, whereby the collected manure is brought back on the fields either as-is or digested (after biogas production). This soil, with and without manure collected from the farm, will be put in columns and incubated for 3 months. As part of the thesis, gas samples will be taken on a regular base during the incubation in order to determine the C and N losses from the columns. At the end of the experiment, the columns will be collected and organic carbon and nitrogen content determined to close the carbon and nitrogen budget.
The main question we hope to answer with your BSc/MSc thesis is if digested manure is releasing less organic carbon from the soil than undigested manure.
Supervisors: Dr. Jeroen Zethof, Johanna Zenner, Dr. Klaus Schützenmeister, Prof. Dr. Hermann Jungkunst
Contact: jeroen.zethof(at)rptu.de
2) Freeze-thaw effect on organic matter mineralization
Subarctic soils undergo regular freeze-thaw cycles over the year, which have an important impact on microbial activity in soils. It is known that upon thawing relative large amounts of CO2 and CH4 can be released by increased microbial activity, which is both an important contributor to climate change and a loss of local soil fertility. Therefore it is important to understand the underlying processes better and how land management practices can be adopted to reduce these losses.
As part of C-arouNd project, we study the carbon and nitrogen cycles at an organic farm in Tingvoll (Norway). Grass-clover leys are used to grow fodder for the farm animals, whereby the collected manure is brought back on the fields either as-is or digested (after biogas production). In this thesis, columns will be created from collected materials from the farm. Part of these columns will be undergo a freeze-thaw cycle, whereby we will sample gas and water samples on a regular base from both the freeze-thaw and control columns.
The main question we hope to answer in your thesis is if the use of digested and/or undigested manure is influencing the release of C and N from the soil during freezing conditions and upon thawing.
Supervisors: Dr. Jeroen Zethof, Johanna Zenner, Dr. Klaus Schützenmeister, Prof. Dr. Hermann Jungkunst
Contact: jeroen.zethof(at)rptu.de
Personal information
See ResearchGate:
Julich, D., Julich, S., Feger, K. H., Klauder, T., Zethof, J.H.T.
Effects of Past Sulfur Deposition on the Soil Microbial Biomass at Spruce Forest Sites. Soil Systems, 8(2), 2024. https://doi.org/10.3390/soilsystems8020037
Bettermann, A., Zethof J.H.T., Babin D., Cammeraat L.H., Solé-Benet A., Lázaro R., Luna L., Nesme J., Sørensen S.J., Kalbitz K., Smalla K., Vogel C.
Importance of microbial communities at the root-soil interface for extracellular polymeric substances and soil aggregation in semiarid grasslands,
Soil Biology and Biochemistry, 108301, 2021.https://doi.org/10.1016/j.soilbio.2021.108301
Baumert V.L., Forstner, S., Zethof, J.H.T., Vogel, C., Heitkötter, J., Schulz, S., Kögel-Knabner, I., Mueller, C.W.
Root-induced fungal growth triggers macroaggregation in forest subsoils,
Soil Biology and Biochemistry, 108244, 2021.https://doi.org/10.1016/j.soilbio.2021.108244
Zethof J.H.T., Bettermann A., Vogel C., Babin D., Cammeraat L.H., Solé-Benet A., Lázaro R., Luna L., Nesme J., Woche S.K., Sørensen S.J., Smalla K., Kalbitz K.
Prokaryotic community composition and extracellular polymeric substances affect soil microaggregation in carbonate containing semiarid grasslands,
Frontiers in Environmental Science, 8:51, 2020. https://doi.org/10.3389/fenvs.2020.00051
Zethof, J.H.T., Leue, M., Vogel, C., Stoner, S.W., Kalbitz, K.
Identifying and quantifying geogenic organic carbon in soils – the case of graphite,
SOIL, 5, 383–398, 2019. https://doi.org/10.5194/soil-5-383-2019
Zethof, J.H.T., Cammeraat, L.H., Nadal-Romero, E.
The enhancing effect of afforestation over secondary succession on soil quality under semiarid climate conditions,
Science of the Total Environment, 652, 1090–1101, 2019. https://doi.org/10.1016/j.scitotenv.2018.10.235
- 09/2010 – 06/2013 BSc Earth Science (physical geography) at University of Amsterdam
Thesis: “Soil Aggregation: On abandoned fields under the vegetation in a semi-arid Mediterranean environment”
- 09/2013 – 08/2016 MSc Earth Science (track Geo-ecological dynamics) at University of Amsterdam
Thesis: “Long-term effects of land-use change on soil quality: Afforestation and land abandonment in semi-arid Spain”
- 09/2013 – 12/2016 MSc Hydrology at Vrije Universiteit (VU) Amsterdam
Thesis: “Long-term effect of afforestation and land abandonment on the soil in semi-arid Spain: Changing Hydrological characteristics of the soil surface”
- 01/2017 – 06/2021 PhD student at Institute of soil science and site ecology, Dresden University of Technology (TUD)
Doctoral dissertation topic: “The role of extracellular polymeric substances from microbes in soil aggregate stabilization in semiarid grasslands”
- 10/2021 – 09/2023 Research and teaching associate at Institute of soil science and site ecology, Dresden University of Technology (TUD), in the DFG funded project "Transition of sulphur nutrition from excessive supply to potential deficiency in spruce forest ecosystems in Central Europe"
- 11/2023 – present Postdoctoral researcher at Institute of Environmental Sciences, University of Kaiserslautern-Landau (RPTU) - campus Landau, in the BMBF funded project “EJP – C-arouNd”