A critical component of my research is to combine molecular-scale analytical techniques and process measurements to determine the mechanisms underlying landscape- and ecosystem-scale phenomena. The goals of this research are to develop innovative and sustainable solutions to environmental pollution.
My research tools are highly applicable to a variety of interdisciplinary environmental questions and problems. If you are interested in working together, please contact me!
My research tools are highly applicable to a variety of interdisciplinary environmental questions and problems. If you are interested in working together, please contact me!
Above (Left to Right): Field sampling for biominerals and metal tolerant microbes at a passive remediation wetland treating acid mine drainage in central PA, transmission electron microscopy image of fungal cell with elemental Se nanoparticles (black circles), Cd/Zn hyperaccumulating plant Noccaea caerulescens grown in a greenhouse study with various contaminated soils, micro-X-ray fluorescence chemical map of Zn (red/orange) in a Noccaea caerulescens leaf, roots and soil in a central PA soil pit, working to position the detector during synchrotron work, scanning electron microscopy image of synthetic goethite particles, and sampling wetland soil cores using rhizon samplers to measure nutrients and metals in a mining impacted area of northern MN.
Fungal biominerals and metal(loid) transformations
Alternaria alternata aerobically reduces selenite to elemental Se nanoparticals, limiting the bioavailability of the toxic metalloid.
Watch a short video of Carla talking about this research!
Fungi are everywhere in the natural environment and can be highly tolerant of contaminants, though their interactions with metals and metalloids remains virtually unknown. Using experimental approaches, I have been working to explore what fungi are tolerant of contamination, and what how the fungi can transform these elements in environmental conditions. Below are a few projects where we are studying fungi in natural and engineered environments to understand how they remove toxic contaminants from water systems:
1. Se biomineralization and volatilization in reclaimed mine soils
2. Mycogenic Mn biominerals in acid mine drainage soils and sediments
3. Se removal by fungi in industrial wastewater systems (in collaboration with Mary Sabuda and Cara Santelli, UMN)
4. Uranium tolerance and biomineral formation (in collaboration with Ken Kemner and Ed
O'Laughlin, Argonne National Lab)
Relevant Publications
Rosenfeld, C.E., Kenyon, J.A., James, B.R., and Santelli, C.M. Selenium (IV,VI) reduction and tolerance by fungi in an oxic environment (2017) Geobiology. 00: 1–12. doi:10.1111/gbi.12224.
Rosenfeld, C.E James, B.R., Santelli, C.M. (2018) Selenium in reclaimed mine soils alters fungal and bacterial community structure and diversity. Applied and Environmental Microbiology. 84(16): eo1394-18. doi:10.1128/AEM.01394-18
Rosenfeld, C.E, Sabuda, M.C., Hinkle, M.A.G., James, B.R., Santelli, C.M. (2020) A fungal mediated cryptic selenium cycle linked with manganese biominerals. Environmental Science and Technology 54(6): 3570-3580 doi: 10.1021/acs.est.9b06022
Sabuda, M.C., Rosenfeld, C.E., DeJournett, T.D., Schroeder, K., Wuolo-Journey, K., Santelli, C.M., (2020) Fungal bioremediation of selenium-contaminated industrial and municipal wastewaters Frontiers in Microbiology 11: 2105. doi:10.3389/fmicb.2020.02105
Microbial community responses to contaminated soils and sediments
​Field work in Soda Springs, Idaho. I collect soil samples to study chemistry, microbiology and molecular biology in seleniferous reclaimed mine soils.
Contaminated and anthropogenically disturbed soils are expected to have different microbial communities than non-disturbed soils, though we still don't understand how those communities relate to elemental cycling, nutrient availability, and contaminant fate and transport. I am involved in several projects aimed at specifically connecting geochemistry with microbial ecology in various environments.
Relevant Publications
Rosenfeld, C.E James, B.R., Santelli, C.M. (2018) Selenium in reclaimed mine soils alters fungal and bacterial community structure and diversity. Applied and Environmental Microbiology. 84(16): eo1394-18. doi:10.1128/AEM.01394-18
Ng, G.-H.C., Rosenfeld, C.E., C.M. Santelli, Yourd, A.R., Lange, J., Duhn, K.D., Johnson, N.W. (2020) Microbial and reactive transport modeling evidence for hyporheic flux-driven cryptic sulfur cycling and anaerobic methane oxidation in a sulfate-impacted wetland-stream system. Journal of Geophysical Research – Biogeosciences 125(2): e2019JG005185 doi: 10.1029/2019JG005185
Kruse, S., Rosenfeld, C.E., Herndon, E.M. (2021) Manganese uptake by red maples in response to mineral dissolution rates in soil Biogeochemistry 155:147-168 doi:10.1007/s10533-021-00817-4
- Bacterial and fungal community in Se contaminated reclaimed phosphate mines in SE Idaho
- Bacterial community in sulfate-impacted hyporheic wetlands in northern Minnesota (in collaboration with Crystal Ng and Cara Santelli, University of Minnesota)
- Bacterial and fungal community in Mn contaminated soils (in collaboration with Beth Herndon, Kent State University)
Relevant Publications
Rosenfeld, C.E James, B.R., Santelli, C.M. (2018) Selenium in reclaimed mine soils alters fungal and bacterial community structure and diversity. Applied and Environmental Microbiology. 84(16): eo1394-18. doi:10.1128/AEM.01394-18
Ng, G.-H.C., Rosenfeld, C.E., C.M. Santelli, Yourd, A.R., Lange, J., Duhn, K.D., Johnson, N.W. (2020) Microbial and reactive transport modeling evidence for hyporheic flux-driven cryptic sulfur cycling and anaerobic methane oxidation in a sulfate-impacted wetland-stream system. Journal of Geophysical Research – Biogeosciences 125(2): e2019JG005185 doi: 10.1029/2019JG005185
Kruse, S., Rosenfeld, C.E., Herndon, E.M. (2021) Manganese uptake by red maples in response to mineral dissolution rates in soil Biogeochemistry 155:147-168 doi:10.1007/s10533-021-00817-4
Contaminant biogeochemistry at the plant-soil interface
Collecting dissolved organic carbon from the rhizosphere of metal hyperaccumulating plants to measure the types of compounds produced by plants when metals are present.
Much work on contaminant metal uptake by plants has been done using hydroponic setups with metal hyperaccumulating plants, which are plants that can take up and tolerate extremely high quantities of ordinarily toxic metals. This has limited our understanding of how solid-phase soil chemistry influences metal cycling and bioavailability to plants. Using a combination of analytical techniques, I explored aspects of Cd, Zn, and C cycling in the rhizosphere of metal hyperaccumulating plants grown in real contaminated soils with a range of contamination sources. These studies combined synchrotron based X-ray absorption spectroscopy and X-ray fluorescence, NMR, and isotope analysis as well as density fractionation and laboratory experiments to understand how plants and metals interact in real soil systems.
This work resulted in several unique and important findings.
1. I demonstrated that common root and microbial exudates mobilize cadmium from complex mineral mixtures common in smelter-contaminated soils (Rosenfeld and Martínez, Environmental Chemistry, 2015).
2. Using greenhouse studies with soils contaminated from different sources, we observed that Cd and Zn were significantly less bioavailable to hyperaccumulating plants than in hydroponic studies. Using synchrotron-based analytical techniques, I specifically linked the diminished plant bioavailability to soil minerals, specifically iron oxides and biogenic metal sulfides, which inhibited metal transfer from soils into hyperaccumulating plants (Rosenfeld et al., JEQ, 2017., Rosenfeld et al., Science of the Total Environment, 2018).
3. Finally, I developed a powerful and easily adaptable tool to capture and comprehensively characterize plant-derived exudates produced by plants grown in contaminated soils. For this I used stable isotope labeling and high resolution NMR to isolate plant-derived compounds, and can be used in the future to facilitate mechanistic studies of rhizosphere processes (Rosenfeld et al., SBB, 2014).
Relevant Publications
Rosenfeld, C.E., McCormack, M.L. and Martínez, C.E. (2014) A novel approach to study composition of in situ produced root- derived dissolved organic matter. Soil Biology and Biochemistry 76:1-4. doi:10.1016/j.soilbio.2014.04.026
Rosenfeld, C.E. and Martínez, C.E. (2015) Dissolution of mixed amorphous-crystalline Cd-containing Fe coprecipitates in the presence of common organic ligands. Environmental Chemistry. 12(6) 739-747. http://dx.doi.org/10.1071/EN14223
Rosenfeld, C.E., Lanzirotti, A., Chaney, R.L., Tappero, R.V. and Martínez, C.E. Micro-scale investigations on soil heterogeneity: Impacts on Zn retention and uptake in Zn contaminated soils. Journal of Environmental Quality 46(2): 373-383
Rosenfeld, C.E., Chaney, R.L. and Martínez, C.E. Cadmium uptake and speciation in hyperaccumulating Noccaea caerulescens grown in field-contaminated soils. Science of the Total Environment 616:279-289
This work resulted in several unique and important findings.
1. I demonstrated that common root and microbial exudates mobilize cadmium from complex mineral mixtures common in smelter-contaminated soils (Rosenfeld and Martínez, Environmental Chemistry, 2015).
2. Using greenhouse studies with soils contaminated from different sources, we observed that Cd and Zn were significantly less bioavailable to hyperaccumulating plants than in hydroponic studies. Using synchrotron-based analytical techniques, I specifically linked the diminished plant bioavailability to soil minerals, specifically iron oxides and biogenic metal sulfides, which inhibited metal transfer from soils into hyperaccumulating plants (Rosenfeld et al., JEQ, 2017., Rosenfeld et al., Science of the Total Environment, 2018).
3. Finally, I developed a powerful and easily adaptable tool to capture and comprehensively characterize plant-derived exudates produced by plants grown in contaminated soils. For this I used stable isotope labeling and high resolution NMR to isolate plant-derived compounds, and can be used in the future to facilitate mechanistic studies of rhizosphere processes (Rosenfeld et al., SBB, 2014).
Relevant Publications
Rosenfeld, C.E., McCormack, M.L. and Martínez, C.E. (2014) A novel approach to study composition of in situ produced root- derived dissolved organic matter. Soil Biology and Biochemistry 76:1-4. doi:10.1016/j.soilbio.2014.04.026
Rosenfeld, C.E. and Martínez, C.E. (2015) Dissolution of mixed amorphous-crystalline Cd-containing Fe coprecipitates in the presence of common organic ligands. Environmental Chemistry. 12(6) 739-747. http://dx.doi.org/10.1071/EN14223
Rosenfeld, C.E., Lanzirotti, A., Chaney, R.L., Tappero, R.V. and Martínez, C.E. Micro-scale investigations on soil heterogeneity: Impacts on Zn retention and uptake in Zn contaminated soils. Journal of Environmental Quality 46(2): 373-383
Rosenfeld, C.E., Chaney, R.L. and Martínez, C.E. Cadmium uptake and speciation in hyperaccumulating Noccaea caerulescens grown in field-contaminated soils. Science of the Total Environment 616:279-289
