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Arpad Thoma

Scientific Employment

Since 2024

Scientific employee, Geobotany and Botanical Garden, Martin-Luther University, Halle-Wittenberg, Prof. Dr. Isabell Hensen

Teaching & Courses

Summer semester

Ökologisches Grundpraktikum (Bachelor Biologie)
Geländepraktikum Müritz Nationalpark (Lehramt Biologie) mit Dr. Mareike Koppik

Research focus

My research focuses on how plant–fungal interactions shape plant invasion processes. I am examining invasion effects at the plant community level. Using network data and ownfield surveys, I want to investigate whether the introduction of alien plant species alters community mycorrhization and mycorrhizal type composition in semi-natural grasslands. Further, I want to evaluate how these patterns depend on plant functional groups, and regional climatic gradients. Another part of my research shifts to a species-level perspective using Conyza canadensis as a model invader. Building on evidence from research of my lab and iCONNECT network, I want to test whether altered plant–fungal interactions may explain its success. Specifically, I want to explore mechanisms of pathogen accumulation that could contribute to increased competitiveness of this species in the non-native range.

Education

Since 2024/06
Doctoral researcher at the Martin-Luther University Halle-Wittenberg.
Supervision: Dr. Christoph Rosche & Dr. Sabrina Träger

2021 - 2024
Master of Science in Biodiversity Science at the Martin-Luther-University Halle-Wittenberg and the iDiv Leipzig (Focus: Plant Ecology & Nature Conservation)

Master thesis on the topic of “Valuation of riparian vegetation in urban environments: A Discrete Choice Experiment Assessment.”

Supervision: Dr. Marek Giergiczny

2015 - 2021
Bachelor of Science in Biology at the Martin-Luther-University Halle-Wittenberg
(Focus: Plant Ecology)

Bachelor thesis on the topic of “Intraspecific variation in the reaction to experimental aridity on 59 Conyza canadensis populations.”

Supervision: Dr. Christoph Rosche

Publications

Callaway, R.M., Pal, R., Schaar, A., Hooper, D., Auge, H., Hensen, I., Kožić, K., Lekberg, Y., Nagy, D.U., Selke, J.A., Thoma, A.E., Träger, S., Rosche, C. (2025). Exotic invasive plant species increase primary productivity, but not in their native ranges. Ecology Letters. (http://dx.doi.org/10.1111/ele.70187   )

Thoma, A.E., Lekberg, Y., Nagy, D. U., Sheng, M., Welk, E., & Rosche, C. (2025). Progress and future directions of biogeographical comparisons of plant-fungal interactions in invasion contexts. New Phytologist. (https://doi.org/10.1111/nph.70228   )

Rosche C., Broennimann O., Novikov A., Mrázová V., Danihelka J., Gastner M.T., Guisan A., Kožić K., Meyer C., Müller-Schärer H., Nagy D.U., Remelgado R., Ronikier M., Selke J.A., Shiyan N.M., Suchan T., Thoma A.E., Zdvořák P., Mráz P. (2024). Herbarium specimens reveal a cryptic invasion of polyploid Centaurea stoebe in Europe. New Phytologist. (https://doi.org/10.1111/nph.20212   )

Nagy D.U., Thoma A.E., Callaway R.M., Hensen I., Stein C., Tsunoda T., Sheng M., Lekberg Y., Slate M., Al-Gharaibeh M., Samartza I., Pal R.W., Frazee L.J., Flory L., Khasa D.P., Jandová K., Shah M.A., Rosche C. (2024). Among‐population variation in drought responses is consistent across life stages but not between native and non‐native ranges. New Phytologist. (https://doi.org/10.1111/nph.19895   )

Lucas M.S., Hensen I., Barratt C.D., Callaway R.M., Durka W., Lekberg Y., Nagy D.U. Onstein, R.E., Shah M.A., van Dam N.M., Thoma A.E., Rosche C. (2024). Re-focusing sampling, design and experimental methods to assess rapid evolution by non-native plant species. Biological Invasions. (https://doi.org/10.1007/s10530-024-03249-x   )

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