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Full-Text Articles in Physical Sciences and Mathematics

Microbial Activity Responses To Water Stress In Agricultural Soils From Simple And Complex Crop Rotations, Jorg Schnecker, D. Boone Meeden, Francisco Calderon, Michel Cavigelli, R. Michael Lehman, Lisa K. Tiemann, A. Stuart Grandy Aug 2021

Microbial Activity Responses To Water Stress In Agricultural Soils From Simple And Complex Crop Rotations, Jorg Schnecker, D. Boone Meeden, Francisco Calderon, Michel Cavigelli, R. Michael Lehman, Lisa K. Tiemann, A. Stuart Grandy

Faculty Publications

Increasing climatic pressures such as drought and flooding challenge agricultural systems and their management globally. How agricultural soils respond to soil water extremes will influence biogeochemical cycles of carbon and nitrogen in these systems. We investigated the response of soils from long-term agricultural field sites under varying crop rotational complexity to either drought or flooding stress. Focusing on these contrasting stressors separately, we investigated soil heterotrophic respiration during single and repeated stress cycles in soils from four different sites along a precipitation gradient (Colorado, MAP 421 mm; South Dakota, MAP 580 mm; Michigan, MAP 893 mm; Maryland, MAP 1192 mm); …


Divergent Controls Of Soil Organic Carbon Between Observations And Process-Based Models, Katerina Georgiou, Avni Malhotra, William R. Wieder, Jacqueline H. Ennis, Melannie D. Hartman, Benjamin N. Sulman, Asmeret Asefaw Berhe, A. Stuart Grandy, Emily Kyker-Snowman, Kate Lajtha, Jessica A. M. Moore, Derek Pierson, Robert B. Jackson Jul 2021

Divergent Controls Of Soil Organic Carbon Between Observations And Process-Based Models, Katerina Georgiou, Avni Malhotra, William R. Wieder, Jacqueline H. Ennis, Melannie D. Hartman, Benjamin N. Sulman, Asmeret Asefaw Berhe, A. Stuart Grandy, Emily Kyker-Snowman, Kate Lajtha, Jessica A. M. Moore, Derek Pierson, Robert B. Jackson

Faculty Publications

The storage and cycling of soil organic carbon (SOC) are governed by multiple co-varying factors, including climate, plant productivity, edaphic properties, and disturbance history. Yet, it remains unclear which of these factors are the dominant predictors of observed SOC stocks, globally and within biomes, and how the role of these predictors varies between observations and process-based models. Here we use global observations and an ensemble of soil biogeochemical models to quantify the emergent importance of key state factors – namely, mean annual temperature, net primary productivity, and soil mineralogy – in explaining biome- to global-scale variation in SOC stocks. We …


Effects Of Timber Harvest On Epigeous Fungal Fruiting Patterns And Community Structure In A Northern Hardwood Ecosystem, Benjamin W. Borgmann-Winter, Ryan B. Stephens, Anthony W. D'Amato, Serita D. Frey, Rebecca J. Rowe May 2021

Effects Of Timber Harvest On Epigeous Fungal Fruiting Patterns And Community Structure In A Northern Hardwood Ecosystem, Benjamin W. Borgmann-Winter, Ryan B. Stephens, Anthony W. D'Amato, Serita D. Frey, Rebecca J. Rowe

Faculty Publications

Epigeous fungal fruiting has important impacts on fungal reproduction and ecosystem function. Forest disturbances, such as timber harvest, impact moisture, host availability, and substrate availability, which in turn may drive changes in fungal fruiting patterns and community structure. We surveyed mushrooms in 0.4 ha patch cuts (18 months post-harvest) and adjacent intact hardwood forest in northern New Hampshire, USA, to document the effects of timber harvest on summer fruiting richness, biomass, diversity, and community structure of ectomycorrhizal, parasitic, and saprobic mushroom taxa. Fungal fruiting richness, diversity, and community heterogeneity were greater in intact forests than patch cuts. Among functional groups, …


Management Intensive Grazing On New England Dairy Farms Enhances Soil Nitrogen Stocks And Elevates Soil Nitrous Oxide Emissions Without Increasing Soil Carbon, Alexandra R. Contosta, Kyle A. Arndt, Eleanor E. Campbell, A. Stuart Grandy, Apryl L. Perry, Ruth K. Varner May 2021

Management Intensive Grazing On New England Dairy Farms Enhances Soil Nitrogen Stocks And Elevates Soil Nitrous Oxide Emissions Without Increasing Soil Carbon, Alexandra R. Contosta, Kyle A. Arndt, Eleanor E. Campbell, A. Stuart Grandy, Apryl L. Perry, Ruth K. Varner

Faculty Publications

Management intensive grazing (MIG), also known as rotational grazing or multi-paddock grazing, is purported to sequester carbon (C) in soils compared to other agricultural management systems. Prior research examining the potential for MIG to enhance soil C has been inconclusive, and past investigations have not addressed whether higher nitrous oxide (N2O) emissions may accompany increases in soil C stocks. Here we examined linkages among MIG, soil C accumulation, and N2O emissions in cool-season, organic pastures of the northeastern United States. We found that pastures under MIG increased soil C concentrations by 11% from 0–15 cm depth but that soil C …


Fungal Community Response To Long-Term Soil Warming With Potential Implications For Soil Carbon Dynamics, Gregory J. Pec, Linda T. A. Van Diepen, Melissa A. Knorr, A. Stuart Grandy, Jerry M. Melillo, Kristen M. Deangelis, Jeffrey L. Blanchard, Serita D. Frey May 2021

Fungal Community Response To Long-Term Soil Warming With Potential Implications For Soil Carbon Dynamics, Gregory J. Pec, Linda T. A. Van Diepen, Melissa A. Knorr, A. Stuart Grandy, Jerry M. Melillo, Kristen M. Deangelis, Jeffrey L. Blanchard, Serita D. Frey

Faculty Publications

The direction and magnitude of climate warming effects on ecosystem processes such as carbon cycling remain uncertain. Soil fungi are central to these processes due to their roles as decomposers of soil organic matter, as mycorrhizal symbionts, and as determinants of plant diversity. Yet despite their importance to ecosystem functioning, we lack a clear understanding of the long-term response of soil fungal communities to warming. Toward this goal, we characterized soil fungal communities in two replicated soil warming experiments at the Harvard Forest (Petersham, Massachusetts, USA) which had experienced 5°C above ambient soil temperatures for 5 and 20 yr at …


A Holistic Framework Integrating Plant-Microbe-Mineral Regulation Of Soil Bioavailable Nitrogen, Amanda B. Daly, Andrea Jilling, Timothy M. Bowles, Robert W. Buchowski, Serita D. Frey, Cynthia M. Kallenbach, Marco Keiluweit, Maria Mooshammer, Joshua P. Schimel, A. Stuart Grandy May 2021

A Holistic Framework Integrating Plant-Microbe-Mineral Regulation Of Soil Bioavailable Nitrogen, Amanda B. Daly, Andrea Jilling, Timothy M. Bowles, Robert W. Buchowski, Serita D. Frey, Cynthia M. Kallenbach, Marco Keiluweit, Maria Mooshammer, Joshua P. Schimel, A. Stuart Grandy

Faculty Publications

Soil organic nitrogen (N) is a critical resource for plants and microbes, but the processes that govern its cycle are not well-described. To promote a holistic understanding of soil N dynamics, we need an integrated model that links soil organic matter (SOM) cycling to bioavailable N in both unmanaged and managed landscapes, including agroecosystems. We present a framework that unifies recent conceptual advances in our understanding of three critical steps in bioavailable N cycling: organic N (ON) depolymerization and solubilization; bioavailable N sorption and desorption on mineral surfaces; and microbial ON turnover including assimilation, mineralization, and the recycling of microbial …


Sodah: The Soils Data Harmonization Database, An Open-Source Synthesis Of Soil Data From Research Networks, Version 1.0, William R. Wieder, Derek Pierson, Stevan Earl, Kate Lajtha, Sara G. Baer, Ford Ballantyne, Asmeret Asefaw Berhe, Sharon A. Billings, Laurel M. Brigham, Stephany S. Chacon, Jennifer Fraterrigo, Serita D. Frey, Katerina Georgiou, Marie-Anne De Graaff, A. Stuart Grandy, Melannie D. Hartman, Sarah E. Hobbie, Chris Johnson, Jason Kaye, Emily Kyker-Snowman, Marcy E. Litvak, Michelle C. Mack, Avni Malhotra, Jessica A. M. Moore, Knute Nadelhoffer, Craig Rasmussen, Whendee L. Silver, Benjamin N. Sulman, Xanthe Walker, Samantha Weintraub May 2021

Sodah: The Soils Data Harmonization Database, An Open-Source Synthesis Of Soil Data From Research Networks, Version 1.0, William R. Wieder, Derek Pierson, Stevan Earl, Kate Lajtha, Sara G. Baer, Ford Ballantyne, Asmeret Asefaw Berhe, Sharon A. Billings, Laurel M. Brigham, Stephany S. Chacon, Jennifer Fraterrigo, Serita D. Frey, Katerina Georgiou, Marie-Anne De Graaff, A. Stuart Grandy, Melannie D. Hartman, Sarah E. Hobbie, Chris Johnson, Jason Kaye, Emily Kyker-Snowman, Marcy E. Litvak, Michelle C. Mack, Avni Malhotra, Jessica A. M. Moore, Knute Nadelhoffer, Craig Rasmussen, Whendee L. Silver, Benjamin N. Sulman, Xanthe Walker, Samantha Weintraub

Faculty Publications

Data collected from research networks present opportunities to test theories and develop models about factors responsible for the long-term persistence and vulnerability of soil organic matter (SOM). Synthesizing datasets collected by different research networks presents opportunities to expand the ecological gradients and scientific breadth of information available for inquiry. Synthesizing these data is challenging, especially considering the legacy of soil data that have already been collected and an expansion of new network science initiatives. To facilitate this effort, here we present the SOils DAta Harmonization database (SoDaH; https://lter.github.io/som-website, last access: 22 December 2020), a flexible database designed to harmonize diverse …


Is A Common Goal A False Hope In Convergence Research?: Opportunities And Challenges Of International Convergence Research To Address Arctic Change, Jessica G. Ernakovich, N. Eklund, Ruth K. Varner, N. Kirchner, J. Jeuring, Katharine Duderstadt, A. Granebeck, E. Golubeva, Asiaq Participants Apr 2021

Is A Common Goal A False Hope In Convergence Research?: Opportunities And Challenges Of International Convergence Research To Address Arctic Change, Jessica G. Ernakovich, N. Eklund, Ruth K. Varner, N. Kirchner, J. Jeuring, Katharine Duderstadt, A. Granebeck, E. Golubeva, Asiaq Participants

Faculty Publications

The Arctic faces multiple pressures including climate change, shifting demographics, human health risks, social justice imbalances, governance issues, and expanding resource extraction. A convergence of academic disciplines—such as natural and social sciences, engineering and technology, health and medicine—and international perspectives is required to meaningfully contribute to solving the challenges of Arctic peoples and ecosystems. However, successfully carrying out convergent, international research and education remains a challenge. Here, lessons from the planning phase of a convergence research project concerned with the health of Arctic waters developed by the Arctic Science IntegrAtion Quest (ASIAQ) are discussed. We discuss our perspective on the …


Retaining Eucalyptus Harvest Residues Promotes Different Pathways For Particulate And Mineral-Associated Organic Matter, Gabriel W. D. Ferreira, Fernanda C. C. Oliveira, Emanuelle M. B. Soares, Jorg Schnecker, Ivo R. Silva, A. Stuart Grandy Mar 2021

Retaining Eucalyptus Harvest Residues Promotes Different Pathways For Particulate And Mineral-Associated Organic Matter, Gabriel W. D. Ferreira, Fernanda C. C. Oliveira, Emanuelle M. B. Soares, Jorg Schnecker, Ivo R. Silva, A. Stuart Grandy

Faculty Publications

Eucalyptus plantations have replaced other (agro)ecosystems over 5.6 Mha in Brazil. While these plantations rapidly accumulate carbon (C) in their biomass, the C storage in living forest biomass is transient, and thus, longer-term sustainability relies on sustaining soil organic matter (SOM) stocks. A significant amount of harvest residues (HR) is generated every rotation and can yield SOM if retained in the field. Yet, there is little information on how managing eucalyptus HR changes SOM dynamics. We used isotopic and molecular approaches in a 3-yr field decomposition experiment where a native grassland has been replaced by eucalyptus plantations to assess how …


Synergies Among Environmental Science Research And Monitoring Networks: A Research Agenda, J. A. Jones, P. M. Groffman, J. Blair, F. W. Davis, H. Dugan, E. E. Euskirchen, Serita D. Frey, T. K. Harms, E. Hinckley, M. Kosmala, S. Loberg, S. Malone, K. Novick, S. Malone, K. Novick, S. Record, A. V. Rocha, B. L. Ruddell, E. H. Stanley, C. Sturtevant, A. Thorpe, T. White, W. R. Wieder, L. Zhai, K. Zhu Feb 2021

Synergies Among Environmental Science Research And Monitoring Networks: A Research Agenda, J. A. Jones, P. M. Groffman, J. Blair, F. W. Davis, H. Dugan, E. E. Euskirchen, Serita D. Frey, T. K. Harms, E. Hinckley, M. Kosmala, S. Loberg, S. Malone, K. Novick, S. Malone, K. Novick, S. Record, A. V. Rocha, B. L. Ruddell, E. H. Stanley, C. Sturtevant, A. Thorpe, T. White, W. R. Wieder, L. Zhai, K. Zhu

Faculty Publications

Many research and monitoring networks in recent decades have provided publicly available data documenting environmental and ecological change, but little is known about the status of efforts to synthesize this information across networks. We convened a working group to assess ongoing and potential cross-network synthesis research and outline opportunities and challenges for the future, focusing on the US-based research network (the US Long-Term Ecological Research network, LTER) and monitoring network (the National Ecological Observatory Network, NEON). LTER-NEON cross-network research synergies arise from the potentials for LTER measurements, experiments, models, and observational studies to provide context and mechanisms for interpreting NEON …


Insect Reproductive Behaviors Are Important Mediators Of Carrion Nutrient Release Into Soil, Brooke K. Woelber-Kastner, Serita D. Frey, Daniel R. Howard, Carrie L. Hall Feb 2021

Insect Reproductive Behaviors Are Important Mediators Of Carrion Nutrient Release Into Soil, Brooke K. Woelber-Kastner, Serita D. Frey, Daniel R. Howard, Carrie L. Hall

Faculty Publications

Current declines in terrestrial insect biomass and abundance have raised global concern for the fate of insects and the ecosystem services they provide. However, the ecological and economic contributions of many insects have yet to be quantified. Carrion-specializing invertebrates are important mediators of carrion decomposition; however, the role of their reproductive activities in facilitating this nutrient pulse into ecosystems is poorly understood. Here, we investigate whether insects that sequester carrion belowground for reproduction alter soil biotic and abiotic properties in North American temperate forests. We conducted a field experiment that measured soil conditions in control, surface carrion alone, and beetle-utilized …


Linking Genes To Traits In Fungi, A. L. Romero-Olivares, Eric W. Morrison, A. Pringle, Serita D. Frey Jan 2021

Linking Genes To Traits In Fungi, A. L. Romero-Olivares, Eric W. Morrison, A. Pringle, Serita D. Frey

Faculty Publications

Fungi are mediators of the nitrogen and carbon cycles in terrestrial ecosystems. Examining how nitrogen uptake and organic matter decomposition potential differs in fungi can provide insight into the underlying mechanisms driving fungal ecological processes and ecosystem functioning. In this study, we assessed the frequency of genes encoding for specific enzymes that facilitate nitrogen uptake and organic matter decomposition in 879 fungal genomes with fungal taxa grouped into trait-based categories. Our linked gene-trait data approach revealed that gene frequencies vary across and within trait-based groups and that trait-based categories differ in trait space. We present two examples of how this …


High Frequency Concurrent Measurements In Watershed And Impaired Estuary Reveal Coupled Doc And Decoupled Nitrate Dynamics, Gopal K. Mulukutla, Wilfred Wollheim, Joseph Salisbury, Richard O. Carey, Thomas Gregory, William H. Mcdowell Jan 2021

High Frequency Concurrent Measurements In Watershed And Impaired Estuary Reveal Coupled Doc And Decoupled Nitrate Dynamics, Gopal K. Mulukutla, Wilfred Wollheim, Joseph Salisbury, Richard O. Carey, Thomas Gregory, William H. Mcdowell

Earth Systems Research Center

Rapid changes in land use, pollution inputs, and climate are altering the quantity, timing and form of materials delivered from watersheds to estuaries. To better characterize these alterations simultaneous measurements of biogeochemical conditions in watersheds and estuaries over a range of times scales are needed. We examined the strength of watershed-estuarine biogeochemical coupling using data of in situ measurements of nitrate, terrestrial dissolved organic carbon (DOC) and chloride collected over a seven-month period in a nitrogen impaired estuary in the northeastern US. The watershed was observed exerting strong control over concentrations of terrestrially derived DOC in the estuary, attributable to …


Assessing Microbial Residues In Soil As A Potential Carbon Sink And Moderator Of Carbon Use Efficiency, Kevin M. Geyer, Jorg Schnecker, A. Stuart Grandy, Andreas Richter, Serita D. Frey Nov 2020

Assessing Microbial Residues In Soil As A Potential Carbon Sink And Moderator Of Carbon Use Efficiency, Kevin M. Geyer, Jorg Schnecker, A. Stuart Grandy, Andreas Richter, Serita D. Frey

Faculty Publications

A longstanding assumption of glucose tracing experiments is that all glucose is microbially utilized during short incubations of ≤2 days to become microbial biomass or carbon dioxide. Carbon use efficiency (CUE) estimates have consequently ignored the formation of residues (non-living microbial products) although such materials could represent an important sink of glucose that is prone to stabilization as soil organic matter. We examined the dynamics of microbial residue formation from a short tracer experiment with frequent samplings over 72 h, and conducted a meta-analysis of previously published glucose tracing studies to assess the generality of these experimental results. Both our …


The Transition From Stochastic To Deterministic Bacterial Community Assembly During Permafrost Thaw Succession, Stacey J. Doherty, Robyn A. Barbato, A. Stuart Grandy, W. Kelley Thomas, Sylvain Monteux, Ellen Dorrepaal, Margareta Johansson, Jessica G. Ernakovich Nov 2020

The Transition From Stochastic To Deterministic Bacterial Community Assembly During Permafrost Thaw Succession, Stacey J. Doherty, Robyn A. Barbato, A. Stuart Grandy, W. Kelley Thomas, Sylvain Monteux, Ellen Dorrepaal, Margareta Johansson, Jessica G. Ernakovich

Faculty Publications

The Northern high latitudes are warming twice as fast as the global average, and permafrost has become vulnerable to thaw. Changes to the environment during thaw leads to shifts in microbial communities and their associated functions, such as greenhouse gas emissions. Understanding the ecological processes that structure the identity and abundance (i.e., assembly) of pre- and post-thaw communities may improve predictions of the functional outcomes of permafrost thaw. We characterized microbial community assembly during permafrost thaw using in situ observations and a laboratory incubation of soils from the Storflaket Mire in Abisko, Sweden, where permafrost thaw has occurred over the …


Fungal Community Structure And Function Shifts With Atmospheric Nitrogen Deposition, Jessica A. M. Moore, Mark A. Anthony, Gregory J. Pec, Lidia K. Trocha, Artur Trzebny, Kevin M. Geyer, Linda T. A. Van Diepen, Serita D. Frey Nov 2020

Fungal Community Structure And Function Shifts With Atmospheric Nitrogen Deposition, Jessica A. M. Moore, Mark A. Anthony, Gregory J. Pec, Lidia K. Trocha, Artur Trzebny, Kevin M. Geyer, Linda T. A. Van Diepen, Serita D. Frey

Faculty Publications

Fungal decomposition of soil organic matter depends on soil nitrogen (N) availability. This ecosystem process is being jeopardized by changes in N inputs that have resulted from a tripling of atmospheric N deposition in the last century. Soil fungi are impacted by atmospheric N deposition due to higher N availability, as soils are acidified, or as micronutrients become increasingly limiting. Fungal communities that persist with chronic N deposition may be enriched with traits that enable them to tolerate environmental stress, which may trade-off with traits enabling organic matter decomposition. We hypothesized that fungal communities would respond to N deposition by …


Plant Invasion Impacts On Fungal Community Structure And Function Depend On Soil Warming And Nitrogen Enrichment, Mark A. Anthony, K. A. Stinson, Jessica A. M. Moore, Serita D. Frey Nov 2020

Plant Invasion Impacts On Fungal Community Structure And Function Depend On Soil Warming And Nitrogen Enrichment, Mark A. Anthony, K. A. Stinson, Jessica A. M. Moore, Serita D. Frey

Faculty Publications

The impacts of invasive species on biodiversity may be mitigated or exacerbated by abiotic environmental changes. Invasive plants can restructure soil fungal communities with important implications for native biodiversity and nutrient cycling, yet fungal responses to invasion may depend on numerous anthropogenic stressors. In this study, we experimentally invaded a long-term soil warming and simulated nitrogen deposition experiment with the widespread invasive plant Alliaria petiolata (garlic mustard) and tested the responses of soil fungal communities to invasion, abiotic factors, and their interaction. We focused on the phytotoxic garlic mustard because it suppresses native mycorrhizae across forests of North America. We …


Stoichiometrically Coupled Carbon And Nitrogen Cycling In The Microbial-Mineral Carbon Stabilization Model Version 1.0 (Mimics-Cn V1.0), Emily Kyker-Snowman, William R. Wieder, Serita D. Frey, A. Stuart Grandy Sep 2020

Stoichiometrically Coupled Carbon And Nitrogen Cycling In The Microbial-Mineral Carbon Stabilization Model Version 1.0 (Mimics-Cn V1.0), Emily Kyker-Snowman, William R. Wieder, Serita D. Frey, A. Stuart Grandy

Faculty Publications

Explicit consideration of microbial physiology in soil biogeochemical models that represent coupled carbon–nitrogen dynamics presents opportunities to deepen understanding of ecosystem responses to environmental change. The MIcrobial-MIneral Carbon Stabilization (MIMICS) model explicitly represents microbial physiology and physicochemical stabilization of soil carbon (C) on regional and global scales. Here we present a new version of MIMICS with coupled C and nitrogen (N) cycling through litter, microbial, and soil organic matter (SOM) pools. The model was parameterized and validated against C and N data from the Long-Term Inter-site Decomposition Experiment Team (LIDET; six litter types, 10 years of observations, and 13 sites …


Microbial Diversity Drives Carbon Use Efficiency In A Model Soil, Luiz A. Domeignoz-Horta, Grace Pold, Xiao-Jun Allen Liu, Serita D. Frey, Jerry M. Melillo, Kristen M. Deangelis Jul 2020

Microbial Diversity Drives Carbon Use Efficiency In A Model Soil, Luiz A. Domeignoz-Horta, Grace Pold, Xiao-Jun Allen Liu, Serita D. Frey, Jerry M. Melillo, Kristen M. Deangelis

Faculty Publications

Empirical evidence for the response of soil carbon cycling to the combined effects of warming, drought and diversity loss is scarce. Microbial carbon use efficiency (CUE) plays a central role in regulating the flow of carbon through soil, yet how biotic and abiotic factors interact to drive it remains unclear. Here, we combine distinct community inocula (a biotic factor) with different temperature and moisture conditions (abiotic factors) to manipulate microbial diversity and community structure within a model soil. While community composition and diversity are the strongest predictors of CUE, abiotic factors modulated the relationship between diversity and CUE, with CUE …


Decomposability Of Soil Organic Matter Over Time: The Soil Incubation Database (Sidb, Version 1.0) And Guidance For Incubation Procedures, Christina Schadel, Jeffrey Beem-Miller, Mina Aziz Rad, Susan E. Crow, Caitlin E. Hicks Pries, Jessica G. Ernakovich, Alison M. Hoyt, Alain Plante, Shane Stoner, Claire C. Treat, Carlos A. Sierra Jul 2020

Decomposability Of Soil Organic Matter Over Time: The Soil Incubation Database (Sidb, Version 1.0) And Guidance For Incubation Procedures, Christina Schadel, Jeffrey Beem-Miller, Mina Aziz Rad, Susan E. Crow, Caitlin E. Hicks Pries, Jessica G. Ernakovich, Alison M. Hoyt, Alain Plante, Shane Stoner, Claire C. Treat, Carlos A. Sierra

Faculty Publications

The magnitude of carbon (C) loss to the atmosphere via microbial decomposition is a function of the amount of C stored in soils, the quality of the organic matter, and physical, chemical, and biological factors that comprise the environment for decomposition. The decomposability of C is commonly assessed by laboratory soil incubation studies that measure greenhouse gases mineralized from soils under controlled conditions. Here, we introduce the Soil Incubation Database (SIDb) version 1.0, a compilation of time series data from incubations, structured into a new, publicly available, open-access database of C flux (carbon dioxide, CO2, or methane, CH4). In addition, …


Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich Jun 2020

Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich

Faculty Publications

Metal contamination of food and water resources is a known public health issue in Arctic and sub-Arctic communities due to the proximity of many communities to mining and drilling sites. In addition, permafrost thaw may release heavy metals sequestered in previously frozen soils, potentially contaminating food and water resources by increasing the concentration of metals in freshwater, plants, and wildlife. Here we assess the enrichment of selected heavy metals in Alaskan soils by synthesizing publicly available data of soil metal concentrations. We analyzed data of soil concentrations of arsenic, chromium, mercury, nickel, and lead from over 1,000 samples available through …


Indolic Glucosinolate Pathway Provides Resistance To Mycorrhizal Fungal Colonization In A Non-Host Brassicaceae, Mark A. Anthony, J. L. Celenza, A. Armstrong, Serita D. Frey Apr 2020

Indolic Glucosinolate Pathway Provides Resistance To Mycorrhizal Fungal Colonization In A Non-Host Brassicaceae, Mark A. Anthony, J. L. Celenza, A. Armstrong, Serita D. Frey

Faculty Publications

Most terrestrial plants form mycorrhizas, but a number of agricultural plants, including the Brassicaceae, are non-mycorrhizal. Brassicaceae can still be colonized by arbuscular mycorrhizal fungi (AMF), but species like Arabidopsis thaliana experience growth reductions following AMF colonization at similar magnitude to that of fungal pathogen infections and lack key genes necessary for nutrient exchange. Arabidopsis also produces specific secondary compounds via the modification of tryptophan, including indolic glucosinolates (IGs), which have anti-fungal properties and may therefore be involved in reducing AMF colonization. This study therefore addressed whether the ability to produce IGs facilitates resistance to AMF colonization and growth suppression. …


Ramped Thermal Analysis For Isolating Biologically Meaningful Soil Organic Matter Fractions With Distinct Residence Times, Jonathan Sanderman, A. Stuart Grandy Apr 2020

Ramped Thermal Analysis For Isolating Biologically Meaningful Soil Organic Matter Fractions With Distinct Residence Times, Jonathan Sanderman, A. Stuart Grandy

Faculty Publications

In this work, we assess whether or not ramped thermal oxidation coupled with determination of the radiocarbon content of the evolved CO2 can be used to isolate distinct thermal fractions of soil organic matter (SOM) along with direct information on the turnover rate of each thermal fraction. Using a 30-year time series of soil samples from a well-characterized agronomic trial, we found that the incorporation of the bomb spike in atmospheric 14CO2 into thermal fractions of increasing resistance to thermal decomposition could be successfully modeled. With increasing temperature, which is proportional to activation energy, the mean residence time of the …


Correcting Tree-Ring Δ13c Time Series For Tree-Size Effects In Eight Temperate Tree Species, Matthew A. Vadeboncoeur, Katie A. Jennings, Andrew P. Ouimette, Heidi Asbjornsen Apr 2020

Correcting Tree-Ring Δ13c Time Series For Tree-Size Effects In Eight Temperate Tree Species, Matthew A. Vadeboncoeur, Katie A. Jennings, Andrew P. Ouimette, Heidi Asbjornsen

Earth Systems Research Center

Stable carbon isotope ratios (δ13C) in tree rings have been widely used to study changes in intrinsic water-use efficiency (iWUE), sometimes with limited consideration of how C-isotope discrimination is affected by tree height and canopy position. Our goals were to quantify the relationships between tree size or tree microenvironment and wood δ13C for eight functionally diverse temperate tree species in northern New England, and to better understand the physical and physiological mechanisms underlying these differences. We collected short increment cores in closed-canopy stands and analyzed δ13C in the most recent 5 years of growth. …


Long-Term Evidence Shows That Crop-Rotation Diversification Increases Agricultural Resilience To Adverse Growing Conditions In North America, Timothy M. Bowles, Maria Mooshammer, Yvonne Socolar, Francisco Calderon, Michel A. Cavigelli, Steve W. Culman, William Deen, Craig F. Drury, Axel Garcia Y Garcia, Amelie C. M. Gaudin, W. Scott Harkcom, R. Michael Lehman, Shannon L. Osborne, G. Philip Robertson, Jonathan Salerno, Marty R. Schmer, Jeffrey Strock, A. Stuart Grandy Mar 2020

Long-Term Evidence Shows That Crop-Rotation Diversification Increases Agricultural Resilience To Adverse Growing Conditions In North America, Timothy M. Bowles, Maria Mooshammer, Yvonne Socolar, Francisco Calderon, Michel A. Cavigelli, Steve W. Culman, William Deen, Craig F. Drury, Axel Garcia Y Garcia, Amelie C. M. Gaudin, W. Scott Harkcom, R. Michael Lehman, Shannon L. Osborne, G. Philip Robertson, Jonathan Salerno, Marty R. Schmer, Jeffrey Strock, A. Stuart Grandy

Faculty Publications

A grand challenge facing humanity is how to produce food for a growing population in the face of a changing climate and environmental degradation. Although empirical evidence remains sparse, management strategies that increase environmental sustainability, such as increasing agroecosystem diversity through crop rotations, may also increase resilience to weather extremes without sacrificing yields. We used multilevel regression analyses of long-term crop yield datasets across a continental precipitation gradient to assess how temporal crop diversification affects maize yields in intensively managed grain systems. More diverse rotations increased maize yields over time and across all growing conditions (28.1% on average), including in …


Carbon Use Efficiency And Its Temperature Sensitivity Covary In Soil Bacteria, Grace Pold, Luiz A. Domeignoz-Horta, Eric W. Morrison, Serita D. Frey, Seeta A. Sistla, Kristen M. Deangelis Jan 2020

Carbon Use Efficiency And Its Temperature Sensitivity Covary In Soil Bacteria, Grace Pold, Luiz A. Domeignoz-Horta, Eric W. Morrison, Serita D. Frey, Seeta A. Sistla, Kristen M. Deangelis

Faculty Publications

The strategy that microbial decomposers take with respect to using substrate for growth versus maintenance is one essential biological determinant of the propensity of carbon to remain in soil. To quantify the environmental sensitivity of this key physiological trade-off, we characterized the carbon use efficiency (CUE) of 23 soil bacterial isolates across seven phyla at three temperatures and with up to four substrates. Temperature altered CUE in both an isolate-specific manner and a substrate-specific manner. We searched for genes correlated with the temperature sensitivity of CUE on glucose and deemed those functional genes which were similarly correlated with CUE on …


Pesticide Seed Treatments Containing Neonicotinoids Have Limited Effect On Soil Microbial Community Structure Under Different Tillage Regimes, Jessica E. Mackay, Richard G. Smith, Jessica G. Ernakovich, Lukas T. Bernhardt Dec 2019

Pesticide Seed Treatments Containing Neonicotinoids Have Limited Effect On Soil Microbial Community Structure Under Different Tillage Regimes, Jessica E. Mackay, Richard G. Smith, Jessica G. Ernakovich, Lukas T. Bernhardt

Faculty Publications

Pesticide seed treatments (PST) which contain fungicides and insecticides are commonly used in agriculture; however, little is known about their effect on soil microbial communities and soil health. Neonicotinoids – controversial insecticides which are common in PST – have received criticism due to potential non-target effects. While fungal pathogens need to be moderated, PST have the potential to disturb broader fungal communities which could lead to reduced nutrient cycling and poor soil health. Given the broad use of PST, their effect on soil fungi needs to be studied within the context of other agricultural management practices. For example, tillage regimes …


Small Soil C Cycle Responses To Three Years Of Cover Crops In Maize Cropping Systems, Anna M. Cates, Matthew D. Ruark, A. Stuart Grandy, Randall D. Jackson Aug 2019

Small Soil C Cycle Responses To Three Years Of Cover Crops In Maize Cropping Systems, Anna M. Cates, Matthew D. Ruark, A. Stuart Grandy, Randall D. Jackson

Faculty Publications

Cover crops are touted for their ability to improve many ecosystem functions in annual cropping systems. In addition to water and nutrient retention, cover crops may influence C cycling by increasing total C inputs to the agroecosystem, stimulating microbial populations, altering main crop residue decomposition rate, or changing litter chemistry over time. We assessed whether annual (rye) or perennial (bluegrass) cover crops in maize cropping systems influenced maize residue decomposition (litterbags) or microbial communities (shotgun metagenomics) in soil and litter, and whether these cover crops had an effect on microbially active pools of C: particulate organic matter (POM) C and …


Agriculture, Ecosystems & Environment, William A. Arigiroff, Donald R. Zak, Rima A. Upchurch, Sydney O. Salley, A. Stuart Grandy Jul 2019

Agriculture, Ecosystems & Environment, William A. Arigiroff, Donald R. Zak, Rima A. Upchurch, Sydney O. Salley, A. Stuart Grandy

Faculty Publications

Fine root litter is a primary source of soil organic matter (SOM), which is a globally important pool of C that is responsive to climate change. We previously established that ~20 years of experimental nitrogen (N) deposition has slowed fine root decay and increased the storage of soil carbon (C; +18%) across a widespread northern hardwood forest ecosystem. However, the microbial mechanisms that have directly slowed fine root decay are unknown. Here, we show that experimental N deposition has decreased the relative abundance of Agaricales fungi (−31%) and increased that of partially ligninolytic Actinobacteria (+24%) on decaying fine roots. Moreover, …


Beyond Static Benchmarking: Using Experimental Manipulations To Evaluate Land Model Assumptions, William R. Wieder, David M. Lawrence, Rosie A. Fisher, Gordon B. Bonan, Susan J. Cheng, Christine L. Goodale, A. Stuart Grandy, Charles D. Koven, Danica L. Lombardozzi, Keith W. Oleson, R. Quinn Thomas Jun 2019

Beyond Static Benchmarking: Using Experimental Manipulations To Evaluate Land Model Assumptions, William R. Wieder, David M. Lawrence, Rosie A. Fisher, Gordon B. Bonan, Susan J. Cheng, Christine L. Goodale, A. Stuart Grandy, Charles D. Koven, Danica L. Lombardozzi, Keith W. Oleson, R. Quinn Thomas

Faculty Publications

Land models are often used to simulate terrestrial responses to future environmental changes, but these models are not commonly evaluated with data from experimental manipulations. Results from experimental manipulations can identify and evaluate model assumptions that are consistent with appropriate ecosystem responses to future environmental change. We conducted simulations using three coupled carbon-nitrogen versions of the Community Land Model (CLM, versions 4, 4.5, and—the newly developed—5), and compared the simulated response to nitrogen (N) and atmospheric carbon dioxide (CO2) enrichment with meta-analyses of observations from similar experimental manipulations. In control simulations, successive versions of CLM showed a poleward increase in …