Embedded Files
©Sybille Neumeyer
Contact:
Freie Universität Berlin, Germany
Institute of Biology - Plant Ecology
tessa.camenzind [at] fu-berlin.de
@tcamenzind.bsky.social
News section
2025: Congrats to Yongxing Cui for getting his work on "Global patterns of nutrient limitation in soil microorganisms" accepted in PNAS. It was an honour to contribute to this study.
2025: Excited to become Associate Editor with Geoderma.
2025: It is a great honour to participate in the MicrobeNet^Net collaboration that aims to connect microbial ecologists around the globe (https://microbenetwork.net/)
2025: Mentoring is key to promote female scientists. I am proud to become a Mentor in the Mothers in Science Program. While it is also rewarding to be a Mentee at the same time within the ProFil Programme of the Berlin University Alliance.
2024: Progressing beyond colonization strategies to understand arbuscular mycorrhizal fungal life history - this is what we suggest in our new Viewpoint Article in New Phytologist. An outcome from a collaboration with the lab of Jeff Powell in Australia, funded by the DAAD.
2024: We are happy to present the fungal economics spectrum based on 28 fungal isolates of the Rillig Lab Coreset - open access in Nature Communications https://www.nature.com/articles/s41467-024-47705-7
This was a massive collaborative effort in the lab of Matthias Rillig. We characterized a wide range of functional traits in saprobic fungal isolates, and combined them with fundamental niche positions and stress tolerance to get more insights into the ecological significance of described trait dimensions.
Main research interests
Currently I am Guest Scientist in the Plant Ecology group at Freie Universität Berlin. My studies focus on the role of fungi and microbes in soil nutrient cycling and carbon dynamics, with a strong emphasis on fungal nutrient use efficiency and carbon cycling in soil.
While my expertise is clearly focused on fungal ecology, I aim to use novel (and old) physiological knowledge on fungi to provide mechanistic insights to relevant processes in soil. This includes for example results on (i) fungal nutrient demands, (ii) the shift in mycelial growth dynamics under resource limitations or (iii) the unexpected stoichiometric flexibility of fungal mycelia. in the context of soil C sequestration, we applied the results on varying stoichiometric C:N:P ratios in ageing hyphae to inform our incomplete understanding of microbial necromass composition. Following an in-depth literature review on microbial death studied in microbiology, this led to the theory of microbial death pathways affecting necromass composition (microbial necromass ≠ microbial biomass), and consequently soil C sequestration. Ongoing experimental work supported these hypotheses. In cooperation with the group of Johannes Lehmann (Cornell University) we were able to reveal chemical alterations in fungal necromass depending on microbial death pathways. Interestingly, due to the dual role of nitrogen in necromass mineralization versus stabilization, in depth characterization of necromass residues via Raman spectrocopy and NanoSIMS techniques revealed an important link of C and nitrogen cycling (work in preparation).
In my ongoing DFG project within the SPP SoilSystems, I use the whole experimental gradient from individual fungal isolates grown on defined C substrates (high mechanistic resolution) to fungal communities in complex soils (maximized realism). The aim is to investigate fungal C use dynamics in saprobic fungi in detail in order to understand fungal-driven processes in soil, focusing on carbon-use efficiency, thermodynamic principles and fungal traits of C substrate use. First results are on the way and will be presented soon.
One interesting outcome of this work were the observation of functional differences among fungal species/isolates, guiding my recent work on fungal traits and life-history strategies. We defined a fungal economics spectrum in soil saprobic fungi, which showed a primary economics spectrum similar to other organism groups. Interestingly, C cycling traits were orthogonal (uncorrelated) to the primary dense-fast spectrum relating to successional dynamics, a finding further supported in a more recent collection of more than 100 isolates of saprobic fungi from agricultural soils (work in preparation).
In collaboration with the group of Jeff Powell at Western Sydney University, we extended these theories towards arbuscular mycorrhizal fungi, exploring together with plant scientists life-history theories in this important symbiotic group.
fungal isolates of my current SPP project ©Tessa Camenzind
large fungal mycelium on a Ø 20 cm plate ©Tessa Camenzind
thick mycelial cords on tropical litter ©Tessa Camenzind
hyphal characteristics visualized by fluorescence stains ©Tessa Camenzind
Former research projects
Interesting patterns of fungal physiology under varying nutrient supply, and their implications for soil processes
We designed fungal growth media suitable to test for growth limitations by individual elements. Responses to N and P limitations tested in many fungal isolates covering three fungal phyla showed very distinct shifts in trait expressions, indicating a switch from explorative growth under low nutrient conditions to exploitative growth with dense and highly active mycelia in high nutrient patches. A parallel analysis of fungal stoichiometric patterns indicated a non-homeostatic shift in C:N:P ratios, contradicting common assumptions of microbial homeostasis. Mechanisms explaining this stoichiometric flexibility also relate to the mycelial lifestyle, which enables nutrient translocation and recycling within the mycelium.
Further projects aim to translate these physiological findings under more controlled conditions towards observations in soil, in order to understand the relevance of stoichiometric fungal shifts in soil, predict carbon versus nutrient limited growth and activity in soil and improve current models of microbial mediated carbon and nutrient cycling dynamics.
Nutrient limitations on microbial growth
The simple agricultural concept of Liebig´s law of the minimum predicts that only the most limiting element in soil restricts plant growth. In natural diverse ecosystems, productivity is indeed often limited by nitrogen (N) and phosphorus (P) availability, though patterns were revealed to be far more complex - with co-limitations occurring, overlooked elements playing important roles and functional or phylogenetic groups being affected differentially by various elements. In recent years a growing number of interesting studies based on nutrient manipulation experiments revealed new insights on this topic, though often with a focus on plants and aboveground processes. Since plant growth and primary productivity depend on nutrient recycling in soil, nutrient demands of soil microbes mediating those processes and above- belowground interactions are of equal relevance. Summarizing available findings on soil microbial responses to nutrient manipulations gave valuable insights on nutrient limitations of soil microbes in general (Camenzind et al. 2018). Additional case studies combining large- and small-scale nutrient manipulation approaches allow for a more detailed analysis of microbial element demands, especially of saprobic fungi (Camenzind et al. 2019). Potential demands for elements like carbon, nitrogen, phosphorus, calcium, potassium or sodium are quantified in controlled media, and actual limitations tested in parallel in field experiments (see Publications).
©Tessa Camenzind
Arbuscular mycorrhizal fungi in response to increasing nutrient inputs
This interest in soil element cycling already started with my PhD thesis “Responses of arbuscular mycorrhizal fungi to nutrient additions in a tropical montane forest”. This exciting project not only got me hooked on working in diverse tropical forests, expanding my knowledge to different ecosystems, but also on thinking more deeply about the interplay of microbes with elements in soil. For years I studied the fascinating symbiosis of arbuscular mycorrhizal fungal communities with plants in respect to soil nutrient status in pristine tropical forests, Dark Earth soils in tropical Africa, as well as tropical but also temperate pasture and grassland systems. Based on the gained knowledge my research interests broadened towards nutrient limitations of other microbial groups in soil, especially saprobic fungi, and consequent implications for ecosystem processes.
©Tessa Camenzind
The ubiquitous group of arbuscular mycorrhizal fungi (AMF) is not only relevant for plant and microbial community dynamics and soil processes, but especially enhances plant nutrient uptake. Thus, nutrient limitations and alteration in element inputs by anthropogenic activities affect this important plant-fungus association. We investigated in multiple study systems the responses of AMF to nutrient manipulations, analyzing extra- and intraradical AMF abundance as well as AMF community structure. In most systems nitrogen (N) and phosphorus (P) availablity strongly control the AMF association and especially species composition (see Publications), though unifying patterns and functional implications are difficult to derive from those complex results. Next steps are to combine observational data with functional experiments, to understand implications of shifts in AMF abundance and communities for ecosystem processes, and combine findings from different systems to detect common patterns enabling us to predict future responses to environmental change.
For details on my research projects please refer to my Publications
Traveling the world as an ecologist
I aimed to be biologist for many reasons, but one of them was definitely to have a job enabling me to explore many places on this planet. Though my Curriculum Vitae may not reflect this passion adequately - for personal reasons I was not able to change my location for longer periods - I still used every opportunity to make short journeys for field trips, scientific exchange and international conferences. I very much enjoyed these interactions, but also the work within the inspiring large international research group of Matthias Rillig and for a long time also as part of the Ecuadorian research unit funded by the Deutsche Forschungsgemeinschaft.
Former News Section contributions:
2024: A newly funded Feodor Lynen Fellowship for 3 + 3 months gives me the chance to work at Cornell University in the group of Johannes Lehmann. This is a truely amazing environment to further explore the role of fungi and microbes in the soil carbon cycling.
2024: I am happy some of my fungal isolates helped to improve our understanding of soil fungal biomarkers - new studies on
(i) insights on the validity of conversion factors for PLFA, ergosterol and rDNA copy numbers and
(ii) galactosammine and mannosamine as potential biomarkers for microbial EPS2023: A short trip funded by the DAAD brought me to Australia, what an exciting journey! This beautiful visit at the Hakwesbury Institute of the Environment (Western Sydney University) in the group of Jeff Powell led to an exciting research exchange about fungal traits. After working on functional traits in saprobic soil fungi for years, it was interesting to think about similarities in arbuscular mycorrhizal fungi (manuscript under review) and get the opportunity to discuss these patterns also with THE scientists who developed life-history frameworks in plants (Ian Wright, Mark Westoby and Will Cornwell).
2023: How do soil microbes die and why does it matter? Find out in our latest Nature Geoscience article "Formation of necromass-derived soil organic carbon determined by microbial death pathways" with co-authors Kyle Mason-Jones, India Mansour, Matthias C. Rillig and Johannes Lehmann
2022: First fungal trait paper accepted: "Soil fungi invest into asexual sporulation under resource scarcity, but trait spaces of individual isolates are unique"
https://ami-journals.onlinelibrary.wiley.com/doi/10.1111/1462-2920.160122022: New DFG project funded in the priority program SPP SoilSystems (SPP 2322): "The significance of saprobic fungi for energy and matter turnover under varying substrate conditions – from individuals to soils"
- for details of the project see soilsystems.net/projects/p8-saprobic-fungi/2022: Latest research is out - fungal root endophytic communities in a tropical biodiversity hotspot located in the Podocarpus National Park, Southern Ecuador
https://ami-journals.onlinelibrary.wiley.com/doi/10.1111/1758-2229.131212021: I am very proud that my research on fungal stoichiometry got featured in an interview in Ratios Matter: http://ratiosmatter.org/issues/ratios-matter-november-2020.pdf
2021: Stoichiometric C:N:P ratios in fungal mycelia are unexpectedly flexible: research on fungal stoichiometry is finally available in Ecology Letters https://onlinelibrary.wiley.com/doi/full/10.1111/ele.13632
2020: How do fungi respond to nutrient limiting conditions? Simple question, and a more complex answer than expected: https://sfamjournals.onlinelibrary.wiley.com/doi/full/10.1111/1462-2920.15132
Page updated
Google Sites
Report abuse