News

Congratulations to Will Argiroff for completing his dissertation in SEAS! Will has been in and around the lab for many years, starting as an undergrad working with one of our postdocs (Zac Freedman), then as research technician doing crazy amounts of qPCR and finally as a PhD student. Will’s work for his PhD research broadly looked at linking microbial communities to decomposition and nutrient cycling in forest ecosystems, but specifically he studied some of the more recalcitrant forms of carbon (lignin and soil organic matter) and the microbes involved in degrading them to make them accessible for other organisms, which have long term consequences for how carbon is stored in these systems as well how nitrogen affects can aid or slow this process. He looked at communities that decay fine roots in both experimentally elevated nitrogen-addition sites, as well as natural forest systems that have a mineralization gradient. He also studied how certain mycorrhizae (ECM) contribute to decay over a span of nitrogen availability. Spoilers – increased nitrogen in the environment slowed root (and lignin) decay leading to SOM accumulation furthermore ECM that can decay SOM effectively declined with increasing N availability, also contributing to slower decay of SOM/lignin. His dissertation is titled “Fungal Community Composition Regulates Fine Root Decay: Implications for the Cycling and Storage of Carbon in Terrestrial Ecosystems”. He will be starting his post-doc at Oak Ridge National Lab in July. Thanks so much Will for all the great memories and all the amazing work! ...

Congratulations to Jennifer Wen for successfully completing her thesis to earn her MS from SEAS! Jennifer started in the lab fall 2020 and managed to complete her thesis despite all the hurdles from pandemic restrictions and supply issues alongside all the usual unexpected issues for environmental research. I feel like there should be a special seal for her diploma. Jennifer’s work looked at a specific gene involved in nitrification, amoA, that is the key process for nitrogen cycling where ammonia is eventually converted to nitrate for uptake by other organisms. This process is only done by specific ammonia-oxidizing microbes, so insight into this gene gives information about those specific microbial communities. Her thesis focused on the archaeal groups (AOA) that have this gene. Using molecular methods and sequencing, Jennifer examined the abundance and diversity of amoA in soil from Manistee National Forest. These sites were of similar age and plant communities but across a natural gradient of inorganic nitrogen amounts in the stands. The amoA communities formed distinct groupings by site, and she tested various environmental variables and found that soil pH and nitrogen mineralization were significantly different across the stands. Her results build and improve on our understanding of the nutrient cycling from a microbial ecology perspective in these forest ecosystems. Her thesis presentation, part of the SEAS Capstone Symposium, was titled “Does Mineralization and pH Control the Distribution of Ammonia-Oxidizing Archaea in Temperate Forest Soils?” and can be found here (link in future) ...

A former member of the Zak lab has recently published a paper, titled “Plant effects on and response to soil microbes in native and non-native Phragmites australis” in Ecology. The aim of the study was to examine if Plant–soil feedbacks (PSFs) mediate plant community dynamics with specific focus on if this could contribute to plant invasions. He did a series of microbial inhibitor treatments on native and non-native Phragmites, but found that opposite of expectations both lineages were negatively impacted, especially the non-native plants, which indicates that that the success of non-native Phragmites is not a result of soil microbe – plant interactions. It can be found here ...

The Soils Lab is looking to hire a new postdoc to work on an upcoming NSF-funded research project. Please read the following announcement below for requirements and inquiries. Postdoctoral Research Associate Microbial Ecology and Plant Physiology A postdoctoral research position is available immediately to study the contribution of organic N via mycorrhizal fungi on plant growth response to elevated atmospheric CO2 . Work will consist of a series of field experiments and data analyses aimed at providing novel insight into variation in plant N uptake and response to eCO2. Candidates must have a Ph.D. in microbial ecology, soil microbiology, biogeochemistry, or closely related field. Expertise with molecular techniques to investigate microbial community composition and function is required. The initial appointment period will be for 1 year with the potential of renewal. Applicants should email a cover letter describing research experience and goals, a curriculum vitae, reprints, and the names and addresses of three references to Drs. Inés Ibáñez ( iibanez@umich.edu ) and Donald R. Zak ( drzak@umich.edu ), School for Environment and Sustainability, University of Michigan, Ann Arbor. The University of Michigan is a non-discriminatory, equal opportunity employer ...

Don was named as a Distinguished University Professor back in July of 2020, which is a top honor at U of M to recognize faculty that have significant achievements and excellence their their chosen fields. Recently, the University held an event for some of the Distinguished University Professorship honorees to give a lecture on their work. Generally recipients give an inaugural lecture on a topic that spans the course of their career or encompasses highlights during their academic advancements. This event was held in Rachkam Amphiteatre on February 8th, 2022. Don gave a lecture on how he seeks to elucidate connections between soil microbial communities and ecosytem-level processes, titled “Soil Microbial Communities and the Future Functioning of Terrestrial Ecosystems”. There is a livestream of the event, including the other professors whom gave a talk Nancy Love (Environmental Engineering) and Arthur Lupia (Political Science), which can be found here ...

Great news for Jennifer Wen, SEAS MS in the Zak lab. She was recently awarded the Peter and Carolyn Mertz Fellowship for her Master’s work. This only highlights what we all know – she’s pretty exceptional. Congrats to Jen!! ...

Will Argrioff, a PhD in SEAs in the Zak lab, has recently published a paper, titled “Decay by ectomycorrhizal fungi couples soil organic matter to nitrogen availability” in Ecology Letters. In this study, interactions between soil nitrogen, fungal community composition and soil organic matter were examined to determine correlations for fungal communities with changes in N availability and SOM, especially lignin-derived SOM. It can be found here ...

A new paper from the Zak lab. Peter Pellitier, former PhD from SEAs, has recently published a paper, titled “Ectomycorrhizal access to organic nitrogen mediates CO2 fertilization response in a dominant temperate tree”, in Nature Communications. This work focused on the linking metagenomic data for ECM fungi and modeling data for N-foraging traits for inorganic and SOM-bound N across a natural mineralization gradient and in response to iCO2. It can be found here ...