Source: PENNSYLVANIA STATE UNIVERSITY submitted to
NITROUS OXIDE CONSUMPTION IN SOILS UNDER ADAPTIVE MANAGEMENT TO CLIMATE CHANGE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1015451
Grant No.
2018-68002-27917
Cumulative Award Amt.
$288,500.00
Proposal No.
2017-07259
Multistate No.
(N/A)
Project Start Date
May 1, 2018
Project End Date
Apr 30, 2022
Grant Year
2018
Program Code
[A3171]- Climate and Land Use
Project Director
Bruns, M. V.
Recipient Organization
PENNSYLVANIA STATE UNIVERSITY
408 Old Main
UNIVERSITY PARK,PA 16802-1505
Performing Department
Ecosystem Science & Management
Non Technical Summary
Improving nitrogen (N) use efficiency and lowering net N2O emissions from agricultural soils are important goals in mitigating agriculture's impact on the environment. Denitrification has been assumed to be the main microbial process responsible for N2O loss from fertilized soil. However, recent research shows that other processes can reverse the effects of denitrification and to increase N cycling efficiency in soils. This proposal focuses on the effects of reduced-tillage, cover cropping and manure additions on N2O reduction by non-denitrifier populations. We hypothesize that the abundance and activity of these populations vary in response to type of management. We will identify cover cropping and fertilization practices affecting these populations in the Sustainable Dairy Cropping Systems (SDCS) experiment established through the Northeast Sustainable Agricultural Research and Extension program. The SDCS experiment, which has been in place for seven years, will become a part of the Long-Term Agricultural Research (LTAR) sites being established by USDA-ARS. Through our collaboration with the Watershed Management and Pasture Systems Lab, the proposed project will enable sampling and analysis to be extended to additional LTAR treatments and sites. Specific objectives will be to: 1) measure abundance, activity and diversity of atypical N2O reducers in SDCS and LTAR soils; 2) measure soil redox changes and N2O emissions.
Animal Health Component
40%
Research Effort Categories
Basic
60%
Applied
40%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
10201101070100%
Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships;

Subject Of Investigation
0110 - Soil;

Field Of Science
1070 - Ecology;
Goals / Objectives
Major goals of this project are to 1) gain fundamental insights into microbial N2O consumption in fertilized soils that are managed for resilience to global change; 2) identify organic amendments and soil conditions which stimulate N2O consumption by newly recognized "atypical N2O-reducing bacteria"; 3) evaluate existing and potential contributions of these bacterial specialists to mitigating global warming impacts in agriculture; 4) provide the opportunity for a postdoctoral scientist to obtain further research experience and advance as a professional; 5) support research by two students earning graduate degrees in Soil Science and Ecology. By analyzing soils from agricultural research plots established and supported by two other USDA programs (Northeast Sustainable Agricultural Research and Education and USDA-ARS-Long Term Agroecosystem Research Network), another goal is to take advantage of prior and ongoing USDA investments in pursuit of new knowledge on soil nitrogen cycling.Technical objectives are to: 1) Assess abundances and activities of atypical N2O-reducing bacteria in soils managed with reduced tillage and increased organic matter inputs (dairy manure and cover crops); 2) Conduct microplot trials within ongoing research experiments to identify organic amendments, soil conditions, and disturbance events that affect atypical N2O-reducers; and 3) Test effects of soil properties (e.g., redox, labile carbon, nitrate concentration) on N2O reducers in laboratory mesocosm experiment. Ultimately, our goal is to to communicate to growers and extension educators how soils can be managed for enhanced nitrogen retention and recycling.
Project Methods
We will measure N2O emissions and abundances of N2O-consuming bacteria in reduced-tillage soils that are cover cropped and/or amended with dairy manures. Soil N2O and CO2 fluxes will be sampled by non-steady state static chamber method. Soil samples will be selected for DNA/RNA extraction based on N2O flux patterns in the field. Quantification and expression of functional genes will be measured using qPCR and RT-PCR. Mesocosm experiments under controlled environments also will be conducted with soils from different treatments, with a specific focus on soils from alfalfa hay and corn rotations.. Soil mesocosms will be incubated with headspaces composed of mixtures of He/O2 for measuring N2O:N2 ratios in withdrawn gas samples and changes in atypical nosZ functional genes. This will allow us to achieve better constraints on soil conditions that influence N2O production and consumption processes. We will obtain estimates of N2O consumption rates to assess their potential integration in the Adapt-N tool available on the USDA Climate Hub website. Most process-based model use a fixed N2O:N2 ratio for predicting the denitrification products and hence are not capable of determining the underlying mechanisms that alter the N2O:N2 ratio during denitrification. The results from this experiment could be potentially be used to develop more precise empirical approximations that could improve N2O model predictability. These experiments can help elucidate how N2O production and consumption respond to soil management.

Progress 05/01/18 to 04/30/22

Outputs
Target Audience:Three main target audiences benefited from this project: agronomists and cropping systems modelers; forage and row crop producers in the mid-Atlantic region; and students. (1) Agronomic and soil scientists were targeted via collaborations and discussions within Penn State and at professional conferences, as well as peer-reviewed journal articles. Research results are currently being publicized by Penn State's College of Agricultural Sciences. (2) for regional growers, our most immediate audience consisted of four dairy farmers and a crop consultant who serve on the Advisory Panel for the Dairy Cropping Systems project. We provided updates to these farmer-advisors twice a year and presented research findings at field days. We also visited other farmer-cooperators to observe farm operations and obtain soil samples (farmer-cooperators in Clinton, Centre, and Lycoming Counties who participated in the Regional Conservation Partnership Program, as well as with members of the Pennsylvania Association for Sustainable Agriculture and the Pennsylvania No-Till Alliance).3) Students (Mara Cloutier, Devyn McPheeters) were mentored by the faculty Co-PIs, who also interact with many other students through their undergraduate and graduate courses (i.e., Soil Ecology, Environmental Soil Microbiology, Plant Science capstone course for Plant Sciences and Agroecology majors, and Ecology of Agricultural Systems. Insights on novel soil-N cycling processes have been incorporated into class discussions, field trips, and hands-on activities. Changes/Problems:Due to early departure of postdoc and inability to hire another postdoc during COVID, two one-year, no-cost extensions were granted for this project, and most of the research was conducted by technician Alcaide and Research Technologist Robbins. What opportunities for training and professional development has the project provided?Although two years of funding for postdoctoral researcher Arnab Bhowmik were originally budgeted in this project, Arnab was fundedforonly three months (after working on a previous USDA NIFA project fortwo years) before takinga faculty position at North Carolina A&T University.Durng his time at Penn State, Arnab was able to take advantage of training through theOffice of Postdoctoral Affairs, and he was an officer in the PSU Postdoc Society.Arnab had trainedtechnician Tiffanie Alcaide and graduate student Mara Cloutieron quantitative PCR analysis, which enabled project research to continue. Because Tiffanie left PSU to attend graduate school and another postdoc could not be hired due to COVID,twoone-year, no-cost extensions were requested.Research Technologist Michael Robbins was hired for he final six months to complete the microcosm study. During this time graduate training in microbiome analysis wasprovided to Ph..D. studentMara Cloutier through the PSU Microbiome Center while she prepared a successful USDA NIFA Predoctoral Fellowship. This Fellowshipenabled Mara to receivedextension training from Dr. Kristi Borelli,Sustainable Agriculture Extension Educator, and to conduct her own soi lmicrobiome research project with four farmer cooperatorsin adjacent counties.GraduatestudentDevyn McPheeters, who was mentored by Bruns, Karsten, and.Curtis Dell of the ARS Pasture Systemsand Watershed Management Unit, was supported by PSU's Dept of Ecosystem Sciences and College of Agricultural Sciences, in a cooperative agreement with USDA-ARS (Long Term Agricultural Research, or LTAR,program,)Cloutier received her Ph.D. in August 2021 and took a position as Project Manager for the Soil Health Institute, Morrisville, NC. McPheeters received her M.S. in May 2022 and is working as a specialistat the Centre County Resource Conservation District. Another Soil Science Ph.D.student, Nina Camillone, receivedtraining in soil microbiome analyses, and plans to graduate in 2023. How have the results been disseminated to communities of interest?Findings from this project have been published in four peer-reviewed articles, one each in Agricultural and Environmental Letters, Ecological Applications, Scientific Reports, and Soil and Tillage Research, with one article in review in Frontiers in Sustainable Food Systems. Project results have also been presentedateight oral or postersessions at Soil Science Society of America meetings in 2019, 2020, and 2021. Updates from this project were given to members of the Advisory Panel for the Dairy Cropping Systems project led by CoPI at Penn State's Agronomy Research Farm. Graduate student Mara Cloutier presented project findings at Ag Progress Days, Penn State'sflagshipagricultural outreach even held every August. Cloutier also discussed her work with farmer-cooperatorsin Clinton, Centre, and Lycoming Counties who participated in the Regional Conservation Partnership Program.. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Outcomes of this project included 1) increased knowledge of the distribution and abundances of soil bacteria that consume N2O in relation to agricultural management (tillage intensity; cover crop termination) in a model midAtlantic dairy cropping system; 2) increased understanding of N2O emissions from soils managed with reduced-tillage and cover cropping;This project had three general hypotheses, formulated as the following null hypotheses: 1) management of agroecosystems does not influence the abundances of gene markers associated with N2O emissions from soils; and 2) conservation management of agroecosystems will not increase soil N2O emissions; and 3) anaerobic conditions during soil incubation will not affect ratios of gene markers for N2O-consumption to N2O-production. This project generated data that supported rejection of all three hypotheses. Management and microcosm incubation conditions did affect N gene abundances, but gene abundances were not reliable indicators of N2O emissions. In the field experiments, for example, gene abundances did not increase after fall termination of a perennial mix in a manured dairy cropping system, even though N2O emissions increased when compared to spring termination. Although this information would be useful to producers deciding when to terminate perennials to accommodate spring planting, the role of weather variability could be more critical in their decision making. In the microcosm experiments, ratios of gene markers for N2O consumption over N2O production were greater under saturated conditions. Ratios were also greater in larger soil aggregates than in smaller aggregates under unsaturated conditions. These findings, although applicable only to the silt loam soils investigated in this project, indicate that N2O emissions are highly responsive to soil conditions and that management could be tuned to achieve the soil conditions that promote more N2O consumption.

Publications

  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Saha, D., Kaye, J.P., Bhowmik, A., Bruns, M.A., Wallace, J.M., Kemanian, A. 2021. Organic fertility inputs synergistically increase denitrification-derived nitrous oxide emissions in agroecosystems. Ecol. Applications, 00(00):e02403. 10.1002/eap.2403
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2022 Citation: Cloutier, M.L., Alcaide, T., Duiker, S.W., Bruns, M.A. in press. Tillage intensity and plant rhizosphere selection shape bacterial-archaeal assemblage diversity and nitrogen cycling genes, Soil and Tillage Research, accepted August 25, 2022.
  • Type: Journal Articles Status: Other Year Published: 2023 Citation: Mara Cloutier, Tiffanie Alcaide, Tyler Bailey, Heather Karsten, Mary Ann Bruns. Management of Perennial Forages Impacts Denitrifier and Nitrate Ammonifier Gene Abundances in a Dairy Cropping Systems Project. In preparation.
  • Type: Theses/Dissertations Status: Published Year Published: 2022 Citation: McPheeters, D.D. 2022. Soil health indicators as tools to understand the effects of disturbance in agroecosystems. M.S. Thesis, The Pennsylvania State University, University Park, PA.
  • Type: Theses/Dissertations Status: Published Year Published: 2021 Citation: Cloutier, Mara L.C. 2021. Toward understanding the impact of management practices on soil microbial nitrogen dynamics in agroecosystems. Ph.D. Dissertation, The Pennsylvania State University, University Park, PA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: McPheeters, Devyn, Karsten, Heather, D, and Bruns, M.A. 2021. Impacts of One-Time Tillage Compared to Continuous No-Tillage on Soil Health in a Diverse Dairy Crop Rotation. Oral Presentation 44-8 at Annual Conference of Soil Science Society of America, Salt Lake City, UT, November 8.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Bruns, Mary Ann, and Cloutier, Mara 2021. Denitrification Gene Pools and Their Relationship to Agroecosystem Management. Oral Presentation at Annual Conference of Soil Science Society of America, Salt Lake City, UT, November 10.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Cloutier, Mara, Duiker, Sjoerd, and Bruns, Mary Ann V. 2019. Microbial N Dynamics Affected by Tillage and Root Exudation. Poster Presentation at ASA-SSSA-CSSA Annual Meetings, Soil Science Society of America, San Diego, CA, January.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Bhowmik, Arnab, Bell, Terrence, Karsten, Heather D., Dell, C.J., and Bruns, Mary Ann V. 2019. Can Bacteria in Manures Help Reduce Nitrogen Losses from Agricultural Soils? Poster Presentation at ASA-SSSA-CSSA Annual Meetings, Soil Science Society of America, San Diego, CA, January.
  • Type: Journal Articles Status: Under Review Year Published: 2022 Citation: McPheeters, Devyn, Bruns, Mary Ann V., Karsten, Heather D., and Dell, Cutis.Integrated Weed Management with Strategic Tillage Can Maintain Soil Quality in Continuous Living Cover Systems, Manuscript ID: 907590 in review for Frontiers in Sustainable Food Systems


Progress 05/01/20 to 04/30/21

Outputs
Target Audience: Nothing Reported Changes/Problems:Requested a secondone-year, no-cost extension What opportunities for training and professional development has the project provided?Graduate students took courses remotely. No lab or field research was conducted due to COVID shutdown. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?When university facilities open, begin search for Research Technologist to complete project.. Funding period is too short to recruit a postdoc.

Impacts
What was accomplished under these goals? No research or outreach was conducted due to COVID.

Publications


    Progress 05/01/19 to 04/30/20

    Outputs
    Target Audience:During the second and third years of this project (with no-cost extension), target audiences receiving information on agricultural practices and greenhouse gas emissions from soils included graduate students, undergraduate students in soil and plant science courses; research and extension faculty; cooperating farmers on advisory board, and members of thePennsylvania Association for Sustainable Agriculture. With the help of Dr. Kristy Borelli, Penn State Sustainable Agriculture Education Specialist, graduate student Mara Cloutier carried out soil sampling on four farms in Clinton County as part of her USDA Predoctoral Fellowship research. Other farmers in our target audience include those who serve on an advisory panel to the Sustainable Dairy Cropping Systems project, which has now transitioned to a Long-Term Agricultural Research (LTAR) site in the USDA-ARS LTAR national network. Changes/Problems:Problems encountered in the completion of this project were departures of key personnel and difficulties in hiring new personnel due to covid shutdown. This project, which had original ending date of April 30, 2020, received a one-year, no-cost extension to April 30 2021. Key personnel were 1) Postdoc who was hired to carry out gene copy analyses left in July 2018 to take a faculty position, 2) his first experiment (incubation study), was continued by the research technologist he trained and completed, but she was not able to start a second experiment with Dairy Cropping Systems soils because she left in March 2020, right before covid shutdown started. PI Bruns has not been able to hire another person, so she is requesting a second, one-year no-cost extension to April 30 2022. What opportunities for training and professional development has the project provided?The postdoc working on this project, Arnab Bhowmik received mentoring from PIs Bruns and Karsten, and he was encouraged to apply for faculty positions. Arnab was recruited to take a faculty position at North Carolina A&T University, which was a great positive step for his career. Prior to Arnab's departure, he trained Tiffanie Alcaide to complete molecular analyses of his samples using quantitative real-time PCR, and Tiffanie was promoted to become a research technologist I. Tiffanie left the project after nine months to pursue graduate studies at another university. Graduate student Mara Cloutier took advantage of online tutorials to gain expertise in bioinformatics analysis pipelines using R programs. Mara, in turn, became a trainer for other graduate students and postdocs when she established a "Data Analysis Working Group" affiliated with Penn State's multidisciplinary Microbiome Center. Mara's professional development was advanced when she obtained a Northeast Sustainable Agriculture Research and Education grant as well as a NIFA Predoctoral grant. Three other graduate students and one undergraduate have benefitted from research experiences in soil quality offered by this project. How have the results been disseminated to communities of interest?Student communities have been influenced directly through introduction of discussion materials on ways to reduce agriculturally related greenhouse gas emissions. Relevant course materials focus on understanding the relationships between N fertilization, cropping systems management, and microbial nitrogen cycling processes which result in net N2O emissions from croplands. Undergraduate courses include SOILS 412W (Soil Ecology) and PLANT 461 (Emerging Issues in the Plant Sciences), with graduate courses SOILS 512 (Environmental Soil Microbiology) and AGRO 510 (Ecology of Agricultural Systems). Presentations by the PIs and graduate students on project results have been made to the Dairy Cropping Systems Advisory Board, field day events at Ag Progress Days Extension In-Service, farmer cooperators in the Regional Conservation Partnership Program, and attendees of professional meetings of the ASA-SSSA-CSSA and Soil and Water Conservation Society. What do you plan to do during the next reporting period to accomplish the goals?PI Bruns is applying for a no-cost extension to enable completion of the work on nosZ genes in amended soils. Our results show that bacterial with typical and atypical nosZ genes coexist in soils, with typical nosZ genes consistently and significantly more abundant. We now recognize that gene copy estimates do not take into account whether the genes may be from extracellular DNA, inactive bacteria, or active bacteria. We propose to use new techniques (propidium monoazide treatment and viability PCR) to assess the proportions of nosZ genes that are found in these different fractions and to determine whether proportions change depending on such factors as nitrate and labile carbon concentrations and soil water content. Graduate student Mara Cloutier will defend her dissertation and graduate with Dual Title PhD in Soil Science and Biogeochemistry in May 2021. Soil Science PhD student Nina Camillone will continue research on determining whether nosZ genes are found in extracellular DNA pools in agricultural soils. Ecology MS student Devyn McPheeters is continuing work on Long Term Agricultural Research soils to assess effects of management on soil aggregate stability and labile carbon pools. She will present findings of her work at the Annual SWCS meeting in 2021. Five manuscripts currently in preparation will be submitted for publication in peer-reviewed journals.

    Impacts
    What was accomplished under these goals? Soil incubation experiments were conducted to evaluate the effect of manure type and soil conditions on the abundance of bacteria possessing typical and atypical genes (nosZ) encoding enzymes that reduce N2O to N2. Changes in bacterial gene markers, concentrations of ammonium and nitrate, and net N2O loss from the soils during incubation were also assessed at two water contents (60% and 95% water-filled pore space). To learn more about how prior management influences soil conditions influencing N2O emissions, two soils with contrasting 7-yr N fertilization histories were used in the incubatiions: 1) fertilized with inorganic N without cover crops and 2) broadcast-manured soils in cover crop rotations. Preliminary results have been presented at the 2020 SSSA annual meeting and a manuscript is under preparation. A key finding was that raw manure contains more bacteria with both types of nosZ genes than liquid digestate, and that application of liquid digestate to soils results in higher N2O emissions. This represents a trade-off for some of the methane reduction benefits associated with anaerobic digestion of manures. On the other hand, soils managed with manure and crop rotations that included cover crops supported lower abundances of bacteria with both types of nosZ genes than soils managed with inorganic fertilizers and no cover crops. These findings suggest that increased organic matter content in soils could also have additional benefit of greater soil N retention via changes in microbial N cycle proccess. In addition to lab incubation experiments, three field experiments were conducted to assess the effects of management on soil bacteria possessing nosZ genes. The first was a long-term tillage experiment comparing rhizosphere and bulk soils of corn and soybean in fields with 40-year histories of moldboard plowing, chisel disking, and no-till. Key finding from this experiment was that no-till soils supported lower relative abundances of denitrifier and N2O-reducing microbes compared to moldboard plowed or chisel-disked soils.The second experiment compared the effects of fall-termination and spring-termination of an alfalfa-orchardgrass cover crop prior to growing corn silage. Key finding was that fall harvest termination decreased abundances of denitrifiers and N2O reducers while the spring termination resulted in increased abundances. These results are reported in manuscripts in preparation for peer-reviewed journals and which will be included in the Ph.D. dissertation of Mara Cloutier. A third experiment was conducted by postdoc Arnab Bhowmik on micro-plots in a larger study to determine effects of combining manure and cover crop residues on nosZ gene copies and denitrication losses. Key finding was that cover crop residues were associated with higher N2O losses in the presence of manures. Results of this experiment were published recently in Ecological Applications. Finally, PhD student Mara Cloutier contributed extensively to another study of soils fertilized with stacked manures by analyzing pyrosequencing data and comparing fungal microbiomes associated with single and mixed cover crops. Cloutier was first author on the paper published in Scientific Reports.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2019 Citation: Bruns, M.A. 2019. Making the most of microbes for soil restoration and function. Research Outreach (108), https://researchoutreach.org
    • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Bhowmik, A., Cloutier, M., Karsten, H., Dell, C.J., and Bruns, M.A. 2020. Denitrifier (typical nosZ) and non-denitrifier (atypical nosZ) abundance in relation to nitrous oxide emissions under climate adaptive management practices. Poster presentation at Annual Soil Science Society of America Meetings, Phoenix, AZ, November 9-13, 2020.
    • Type: Journal Articles Status: Published Year Published: 2020 Citation: Cloutier, M.L., Murrell, E., Kaye, J., Barbercheck, M., Finney, D., Gonzalez, I.G., Bruns, M.A., Fungal community shifts in soils with varied cover crop treatments and edaphic properties. Scientific Reports 10:Article 6198 https://www.nature.com/articles/s41598-020-63173-7
    • Type: Journal Articles Status: Published Year Published: 2019 Citation: Cloutier, M.L., Bhowmik, A., Bell, T.H., Bruns, M.A. Innovative technologies can improve understanding of microbial nitrogen dynamics in agricultural soils. Agricultural and Environmental Letters 4(1):190032 https://acsess.onlinelibrary.wiley.com/doi/abs/10.2134/ael2019.08.0032
    • Type: Journal Articles Status: Awaiting Publication Year Published: 2021 Citation: Saha, D., Kaye, J.P., Bhowmik, A., Bruns, M.A., Wallace, J.M., Kemanian, A. in press. Organic fertility inputs synergistically increase denitrification-derived nitrous oxide emissions in agroecosystems. Ecol. Applications, Manuscript ID EAP20-0519.R1
    • Type: Book Chapters Status: Awaiting Publication Year Published: 2021 Citation: Bruns, M.A., and Couradeau, E. 2021. Sustainable Soil Health., in A. Ricroch et al. (eds), Plant Biotechnology. 2nd edition, Springer.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: McPheeters, D., Karsten, H.D., Bruns, M.A. 2020. Changes in soil health indicators over nine years in rotational cropping systems. Poster presentation at Annual Soil Science Society of America Meetings, Phoenix, AZ, November 9-13, 2020.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Camillone, N., Bruns, M.A. 2020. Affordable and informative soil health testing for small-holder farmers. Poster presentation at Annual Soil Science Society of America Meetings, Phoenix, AZ, November 9-13, 2020.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Cloutier, M., Borelli, K., Bruns, M.A. 2020. Microbiomes are complicated: how can we better communicate their importance to the agricultural community? Poster presentation at Annual Soil Science Society of America Meetings, Phoenix, AZ, November 9-13, 2020.


    Progress 05/01/18 to 04/30/19

    Outputs
    Target Audience:During the first year of this project, target audiences receiving information on agricultural practices and greenhouse gas emissions from soils included regional farmers; students, research and extension faculty, and members of the Pennsylvania Association for Sustainable Agriculture. With the help of Dr. Kristy Borelli, Penn State Sustainable Agriculture Education Specialist, and Lisa Blazure, NRCS, four farmers in Clinton County's Sugar Valley were identified for a soil health study conducted by graduate student Mara Cloutier as part of her USDA Predoctoral Fellowship research. Other farmers in our target audience include those who serve on the advisory panel to the Sustainable Dairy Cropping Systems project, which will be transitioning to one of the Long-Term Agricultural Research (LTAR) sites coordinated by USDA-ARS. Both undergraduate and graduate students at Penn State learn about our USDA-funded research in classes and discussions. Our team also interacts with other Penn State research and extension faculty conducting research at Rock Spring Agronomy Farm. Changes/Problems:One problem is that we are behind in getting data on the nosZII gene markers. This is due to lack of suitable DNA for standard curves, and we are continuing to work on that. The data we have obtained so far has been of poor quality due to problems with the PCR equipment. Troubleshooting efforts are ongoing. What opportunities for training and professional development has the project provided?Graduate student Mara Cloutier received the Francis E. Clark Soil Biology Scholarship at the 2019 Soil Science Meetings in San Diego. Cloutier also is being mentored by Dr. Kristy Borelli, who has conducted outreach and organized field days for the Regional Conservation Partnership Prgoram funded by NRCS. How have the results been disseminated to communities of interest?Graduate students Mara Cloutier and Emily Ball have presented at field days at Rock Spring Agronomy Farm.Clloutier has also participated in field days for the Regional Conservation Partnership Prgoram funded by NRCS. Project Director Bruns and CoPI Karsten communicate on a regular basis with farmers on the advisory panel for the Sustainable Dairy Cropping System. What do you plan to do during the next reporting period to accomplish the goals?Graduate student Emily Ball will graduate with MS in Soil Science in May 2019. Graduate student Mara Cloutier will carry out soil sampling on four farms in Clinton County for her pre-doctoral research project. We will continue to collect data for manuscript preparation on bacteria that consume nitrous oxide in soils under climate-adaptive management. With funding from Northeast SARE ending, the SDCS experiment is expected to transition to an LTAR (Long-Term Agricutural Research) site within the USDA-ARS LTAR network.

    Impacts
    What was accomplished under these goals? Soil samples from the Sustainable Dairy Cropping System (SDCS) experiment established in 2012, are being analyzed for gene markers indicating the presence of bacteria capable of reducing nitrous oxide (a potent greenhouse gas) to inert dinitrogen gas (N2). The gene marker that we want to track is for nosZII (alternative nitrous oxide reductase) in soils under climate-adaptive management, specifically winter cover cropping combined with no-till and manure application. We have encountered difficulties in obtaining bacterial DNA for making a standard curve to test for this gene marker by quantitative PCR. During this period, we encountered setbacks and spent considerable time troublehooting the PCR equipment. We continued to take samples and store them in the frozen state to be analyzed once technical problems were overcome.

    Publications

    • Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Saha, D., Kemanian, A.R., Bhowmik, A., Bruns, M.A., Wallace, J.M., Kaye, J.P. Nitrous oxide emission from organic grain and silage production systems  magnitude, drivers, and source attribution. Submitted to Ecological Applications
    • Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Cloutier1, M.L., Murrell, E., Barbercheck, M., Kaye, J.P., Finney, D., Garc�a-Gonz�lez, I., and Bruns, M.A. Fungal community shifts in soils with varied cover crop treatments and edaphic properties
    • Type: Journal Articles Status: Published Year Published: 2019 Citation: Bruns, M.A. Making the most of microbes for soil restoration and function. Research Outreach Issue 109: 98-101 http://cdn.researchoutreach.org/Flipbooks/RO108/index.html
    • Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Bruns, Mary Ann, Xin Peng, Ryan Trexler, and Terrence Bell. 2018. Provision of agroecosystem services by soil-surface microbial consortia. Penn State Microbiome Center Networking Event, Oct. 2, University Park, PA.
    • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Mara Cloutier, Sjoerd William Duiker, Mary Ann Bruns. Microbial N Dynamics Affected By Tillage and Root Exudation. Poster Presentation at Soil Science Society of America Meetings, San Diego, CA.