This course, which is organised by the University of Tübingen and offered in cooperation with the DBG working group "Isotopes in Soil Science" and Commission IV of the DBG, is aimed at young scientists (PhD students, postdocs, master's students) who already use or would like to use different tracer methods and isotopes (natural abundance and isotope labelling) in their experiments.

The following topics are covered:

• Introduction to isotopes
• Stable and radioactive isotopes; types of radioactive radiation
• Methods of measuring stable and radioactive isotopes
• Compound-specific isotope analysis with LC, GC
• Methods for natural abundance: isotope fractionation and its application
• Tracer methods: a) isotopic labelling, b) non-isotopic labelling
• Possibilities and limitations, detection limits, artefacts
• Evaluation of different tracer methods, sources of interpretation errors
• Safety and special features of working with radioactive isotopes

Applications in soil science process include (E&OE):

• Carbon cycle and humus research (¹⁴C, ¹³C, δ¹³C, Bomb-¹⁴C)
• Soil-plant and rhizosphere interactions (¹⁴C,¹³C, δ¹³C, ¹⁵N)
• Processes of gas emission from the soil (δ¹³C of CO₂ and CH₄, isotopologues of N₂O and N₂
• Nutrient uptake by the plant (¹⁵N, ³²P, ³³P, K-Rb)
• Water absorption by the plant (²H, ¹⁸O)
• Incubation experiments on soil respiration and degradation of plant residues and pesticides in the soil (¹⁴C, ¹³C, δ¹³C)
• Erosion estimation (¹³⁷Cs, ⁷Be, ²¹⁰Pb)
• Phosphor imaging for allocation studies (¹⁴C, ³²P, ³³P)
• Sorption and exchange studies (³²P, ³³P)
• Paleo reconstructions (¹³C, ¹⁸O, D and radiocarbon dating)
• Microbial growth and metabolism (DNA/RNA SIP with ¹³C, ¹⁵N and ¹⁸O, position-specific labelling and metabolic flux modelling)

This is a hybrid event and can be attended either remotely (Zoom) or on site in Tübingen (then also with two lab tours). The event will be held in English and is free of charge.

Lecturers involved: Prof Dr Michaela Dippold, Dr Caroline Buchen-Tschiskale, Dr Svenja Stock, Dr Ilonka Engelhardt, and Dr Callum Banfield

Date: 24^th to 28^th of February 2025