Progress 03/01/21 to 02/28/25
Outputs
Target Audience:The target audience for research activities during the reporting period includes other scientists carrying out research to understand the influence of climate on changes in soil. Specifically, soil scientists, global land modelers, hydrologists, geomorphologists, and biogeochemists. Other audiences include students in classes into which outcomes of the research have been incorporated. Specifically, graduate students in the hydrologic sciences, geosciences, and ecological sciences. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Our group meets monthly over Zoom to provide cross-disciplinary training of undergraduate, graduate, postdoc, and PIs. The group is roughly 20 individuals of various backgrounds, and we spend the first half of the meeting leading lectures on hydrology, biology, statistics, and modeling. We use the second half of the meeting to discuss how we use those foundational concepts to interpret data and develop numerical models. How have the results been disseminated to communities of interest?Our efforts thus far have been disseminated to scientific communities of interest at conferences such as SSSA, Goldschmidt, and AGU in 2024 What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
1) Major Activities: Q1) How do biotic and abiotic drivers of the formation, stability, and collapse of soil aggregate size classes interact to control the life-cycle of aggregates across diverse soil profiles? Graduate student Lola Klamm (University of Kansas) finished the analysis of the laboratory experiments to determine the rates of aggregate formation and collapse in response to binding agent abundances, mineral surface area, and overburden pressures. This work was presented at AGU (December 2024), and is being transformed into a manuscript to be submitted in the spring of 2025. Graduate student Annalise Guthrie (University of Kansas) has developed a manuscript titled "Deep Root Loss and Regeneration Change Deep Soil Structure in the Anthropocene" to be submitted to Earth's Future in February 2025. The work uses a large-scale dataset across four soil orders to examine how root loss in croplands and root regeneration in post-cropland systems in B horizons alters multiple soil structural attributes, well beneath tillage zones. Findings reveal that the degree of pedogenic development modulates the extent of structural transformations, with less-developed soils showing greater susceptibility to root-driven structural shifts. These soil structural changes are relevant for water flowpaths, soil carbon retention, and nutrient transport throughout the subsurface. Dr. Laura Podzikowski, a post-doc at KU funded via a different grant, contributes to this project by working with the NRCS dataset described above. Billings and Podzikowski have demonstrated how increasingly flashy precipitation patterns are linked to less well-developed soil, and how structural attributes in the A horizon can govern development of the B horizon. These features vary with soil order and land cover type. This work was presented at Soil Science Society of America (November 2024) and is being transformed into a manuscript to be submitted in summer 2025. Q2) How does aggregate life-cycles and arrangement drive pore geometry at horizon and pedon scales, and, thus, the water and C fluxes? Daniel Hirmas submitted a paper titled " Predicting soil macroporosity and hydraulic conductivity dynamics: A model for integrating laser-scanned profile imagery with soil moisture sensor data" to Water Resources Research. The manuscript presents a new theory of soil structure for predicting changes in macroporosity from matrix soil water content. Former graduate student Lena Wang (Oregon State University) submitted a paper titled "Soils signal key mechanisms driving greater protection of organic carbon under aspen compared to spruce forests in a North American montane ecosystem" to Biogeosciences. This manuscript explores the combination of biological, chemical, physical, and environmental conditions to evaluate potential abiotic and biotic mechanisms of SOC preservation at multiple depths. The data suggest enhanced biotic activities in aspen-dominated forest soils that promote both chemical and physical protection of SOC in aspen- relative to spruce-dominated forests, and associated limitations on DOC export. Postdoc Karla Jarecke published the article "Woody encroachment modifies subsurface structure and hydrological function" in Ecohydrology, and has drafted an additional manuscript titled "Enhanced soil drying primes subsurface for moisture whiplash in mesic woody-encroached grassland" to be submitted for publication in JGR Biogeosciences Undergraduate student Bethany Blackey presented a poster at AGU (December 2024) titled "How Does Juniper Encroachment Impact Soil Hydrological Processes Beneath Our Feet in Sagebrush Steppe?". This poster explored the impact of juniper encroachment on soil properties at our Reynolds creek site. Q3) Do land surface controls on aggregate life-cycles and arrangement propagate to influence the magnitude and variability of soil hydraulic properties at depth? Matthew Amato (UC Riverside) has developed a manuscript titled "Predicting the depth distribution of soil hydraulic conductivity from the land surface" to be submitted to Science. The manuscripts present analysis of a global dataset to show that soil development results in an exponential decrease in saturated hydraulic conductivity with depth that can be predicted from properties at the land surface. This work was also presented at SSSA in 2024. Q4) How and to what degree do climate drivers and soil structural properties shape water and C fluxes at the hillslope to watershed scale? Graduate student and now postdoc Kayalvizhi Sadayappan (Penn State University) has developed a manuscript titled " Does streamflow drive stream chemistry in intermittent streams?". Here the manuscript presents a moving window that reveals "hidden" concentration-discharge behavior patterns varying at the monthly scale. She is also working on a reactive transport model of DIC and DOC at woody encroached sites. Fiona Liu (Penn State University) presented a poster at AGU (2024) titled "Legacy Implications of Deforestation on Subsurface Flow Paths and the Production and Export of Dissolved Carbon Species" and has drafted a manuscript. Here the manuscript explores the impact of land cover differences on DOC production and export by conducting a comparative study using discharge, stream chemistry data, and the BioRT-HBV reactive transport model, between a secondary-growth and an old-growth forest in the H.J. Andrews Experimental Forest. The target submission date for the manuscript is 3/31/2025. Q5) How does the evolution of soil properties control land-atmosphere exchanges of water, energy, and C, and thus influence climate at the continental scale? Graduate student Kachinga Silwimba (Boise State) presented a poster at AGU titled "History Matching with Evidential Deep Neural Networks to Improve Terrestrial Water Storage Simulations in the Community Land Model". This work is currently being developed into a manuscript that focuses on accurate simulation of terrestrial water storage. 2) Specific Objectives: quantify the rates of aggregate collapse and formation advance understanding of how modified subsurface structure influences potential for SOC losses synthesize data across all sites. Develop models that allow us to explore the impacts of subsurface change on water and carbon fluxes. 3) Significant results: See major activities. 4) Key outcomes or Other achievements: We organized and led a 2-day workshop at the 2024 Earth Educators' Rendezvous (EER) in Philadelphia, PA entitled, "Understanding Signals in the Soil: Data-centered learning in critical zone science." This workshop targeted Earth science undergraduate-student educators (graduate students, postdoctoral fellows, lecturers, and faculty) seeking to employ data-centered learning techniques in their courses. Specific goals were for participants to: (1) Understand basic concepts about physical, chemical and morphological characteristics of soils; (2) Learn approaches for teaching students how to investigate likely causes of soil variation; (3) Design activities to help students investigate, plot, and interpret observational data and develop process-based hypotheses about the critical zone; and (4) Understand and apply the concepts of backward design. Key achievements from this workshop were: Development of a Shiny app (https://cuahsi.shinyapps.io/US_Soil_Data_App/) that educators can use to visualize soil, climate, and land use data within the Pedogenic and Environmental DataSet (PEDS) in undergraduate courses (lectures, labs, and assignments). Slide decks for instructors teaching basic soil concepts for critical zone science Five examples of scaffolded assignments built from backward design principles using the new Shiny app for teaching students how to examine observational data, develop hypotheses and make predictions, evaluate hypotheses, and consider sources of variability. Development of participant-created data-centered learning assignments during the workshop.
Publications
- Type:
Peer Reviewed Journal Articles
Status:
Under Review
Year Published:
2025
Citation:
Wang, L., Billings, S., Li, L., Hirmas, D.R., Johnson, K., Kerins, D., Pacho, J., Beutler, C., Jarecke, K, Varikuti, V., Unruh, M, Ajami, H., Barnard, H.R., Flores, A., Williams, K., & Sullivan, P.L. (2025). Soil signals key mechanisms driving greater protection of organic carbon under aspen compared to conifer in a North American montane ecosystem. Biogeosciences. (in review)
- Type:
Other Journal Articles
Status:
Under Review
Year Published:
2025
Citation:
Hirmas, D.R., Ajami, H., Sena, M., Zhang, X., Cao, X., Li, B., Jarecke, K., Billings, S.A., Pachon, J.C., Li, L., Nippert, J.B., Souza, L.F.T., Flores, A., & Sullivan, P.L. (2025). Predicting macroporosity and hydraulic conductivity dynamics: A model for integrating laser-scanned profile imagery with soil moisture sensor data. Water Resources Research. (in review)
- Type:
Other Journal Articles
Status:
Under Review
Year Published:
2025
Citation:
Amato, M.T., Cueva, A., Hirmas, D., Ajami, H., Nemes, A., Billings, S.A., Flores, F., Li, L. Nippert, J., Rudick, A., Singha, K., & Sullivan, P.L. (2025). Is the depth distribution of soil hydraulic conductivity predictable from the land surface? Water Resources Research
- Type:
Peer Reviewed Journal Articles
Status:
Published
Year Published:
2024
Citation:
Jarecke, K.M., Zhang X., Keen, R.M., Dumont, M., Li B., Sadayappan, K., Moreno, V., Ajami, H., Billings, S.A., Flores, A., Hirmas, D.R., Kirk, M., Li, L., Nippert, J.B., Singha, K., & Sullivan, P.L. (2024). Woody encroachment modifies subsurface structure and hydrological function. Ecohydrology. doi: 10.1002/eco.2731.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Amato, M. T., Cueva, A., Hirmas, D. R., Ajami, H., Nemes, A., Billings, S. A., Flores, A., Li, L., Nippert, J., Rudick, A., Singha, K., & Sullivan, P. L. (2024) Developing a New Generation of Pedo-Transfer Functions to Predict the Depth Distribution of Saturated Hydraulic Conductivity from the Land Surface [Abstract]. ASA, CSSA, SSSA International Annual Meeting, San Antonio, TX. https://scisoc.confex.com/scisoc/2024am/meetingapp.cgi/Paper/161888
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Varikuti, V., Bronnikova, M., Hirmas, D. R., Ajami, H., Pachon, J. C., Nippert, J., Sullivan, P. L., Li, L., Billings, S. A., & Flores, A. (2024) Changes in Soil Macro- and Micromorphology As Influenced By Subsurface Shallow Lithic Contact [Abstract]. ASA, CSSA, SSSA International Annual Meeting, San Antonio, TX. https://scisoc.confex.com/scisoc/2024am/meetingapp.cgi/Paper/161380
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Blakey, B., Jarecke, K. M., Dumont, M., Li, B., Sullivan, P. L., Flores, A. N., Hirmas, D., Billings, S. A., Li, L., & Singha, K. (2024). How does juniper encroachment impact soil hydrological processes beneath our feet in sagebrush steppe? AGU fall meeting, Washington DC.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Jarecke, K. M., Keen, R., Sadayappan, K., Nippert, J. B., Billings, S. A., Hirmas, D., Li, L., Ajami, H., Flores, A. N., Kirk, M. F., Singha, K., & Sullivan, P. L. (2024). Woody encroachment intensifies soil drying at multiple temporal scales. AGU fall meeting, Washington DC.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Klamm, L., Hirmas, D., Sullivan, P. L., Flores, A. N., Ajami, H., Li, L., & Billings, S. A. (2024). Unraveling how microbial biomass drives aggregate lifecycles and water flows through diverse soil profiles. AGU fall meeting, Washington DC.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Liu, F., Ajami, H., Billings, S. A., Flores, A. N., Hirmas, D., Nippert, J. B., Singha, K., Sullivan, P. L., Li, L. (2024). Legacy Implications of Deforestation on Subsurface Flow Paths and the Production and Export of Dissolved Carbon Species. AGU fall meeting, Washington DC.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Silwimba, K., Flores, A. N., Becker, C., Hawkins, L. R., Dagon, K., Cionni, I., Sullivan, P. L., Billings, S. A., Ajami, H., Hirmas, D., Li, L., Nippert, J. B., & Amato, M. (2024). History matching with evidential deep neural networks to improve terrestrial water storage simulations in the community land model. AGU fall meeting, Washington DC.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Varikuti,V., Bronnikova, M., Hirmas, D. Ajami, H., Pachon, J., Nippert, J., Sullivan, P.L., Li, L., Billings, S., Flores, A. (2024) Assessing the Influence of Shallow Lithic Contacts on Soil Structure and Hydraulic Properties. SSSA. Puerto Rico.
- Type:
Peer Reviewed Journal Articles
Status:
Under Review
Year Published:
2025
Citation:
Silwimba, K., Flores, A. N., Cionni, I., Billings, S. A., Sullivan, P. L., Ajami, H., Hirmas, D. R., and Li, L.: Soil Parameterization in Land Surface Models Drives Large Discrepancies in Soil Moisture Predictions Across Hydrologically Complex regions of the Contiguous United States, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2025-713, 2025.
|
Progress 03/01/23 to 02/29/24
Outputs
Target Audience:The target audience for research activities during the reporting period includes other scientists carrying out research to understand the influence of climate on changes in soil. Specifically, soil scientists, globalland modelers, hydrologists, geomorphologists, and biogeochemists. Other audiences include students in classes into which outcomes of the research have been incorporated. Specifically, graduate students in the hydrologic sciences, geosciences, and ecological sciences. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Our group meets monthly over Zoom to provide cross-disciplinary training of undergraduate, graduate, postdoc, and PIs. The group is roughly 20 individuals of various backgrounds, and we spend the first half of the meeting leading lectures on hydrology, biology, statistics, and modeling. We use the second half of the meeting to discuss how we use those foundational concepts to interpret data and develop numerical models.? How have the results been disseminated to communities of interest?Our efforts thus far have been disseminated to scientific communities of interest at conferences such as Goldschmidt, SSSA, and AGU in 2022. In addition, Dr. Sullivan presented the group's results to ~300 participants in Moos Family Lecture Series hosted by the non-profit organization Freshwater (https://freshwater.org/moos-family-lecture-series/).? What do you plan to do during the next reporting period to accomplish the goals? Analyze data from the aggregate turnover experiment Complete the development of the structure-from-motion method for capturing in situe macroporosity distributions Finishing analyzing soils from HJA Complete the VisNIR calibration library to convert planned soil monolith scans into high-resolution chemomaps Collect soil property data Reynolds Creek Continue analyze the PEDS dataset and compare results to the newly-developed NEON dataset Link remotely sensed data to soil properties databases Continue with modeling at HJA and to pull modeling datasets together for Reynolds Creek Create point scale simulations with the Community Land Model at HJA and Reynolds Creek to enable cross comparison with other methods and field efforts.
Impacts
What was accomplished under these goals?
1) Major Activities: Graduate student Lola Klamm (University of Kansas) has conducted experiments to determine the rates of aggregate formation and collapse in response to binding agent abundances, mineral surface area, and overburden pressures in a laboratory setting. Lola has run infiltrometer tests on the samples to determine hydraulic properties, and she is in the process of sending samples to OSU for rare earth element analysis and to Texas Tech for pore-size distribution analysis. Her work includes the use of a 13C tracer that will permit estimation of the C sources mineralized vs. retained in soil aggregates. Data from this experiment will provide quantitative metrics of the linkages between SOC mineralization and protection, rates of soil pore generation, and (eventually) their influence on soil water fluxes. In the previous reporting period, undergraduate student Clarissa Carretta (UC Riverside) had linked the NRCS morphological descriptions of every NEON Megapit and distributed pits to the chemical and soil property data available on the NEON website. In the past year, these morphological descriptions were converted to semi-quantitative metrics that allow, for the first time, the parametric statistical analyses of soil structure collected in the same timeframe across the US Ecoclimate domains. Such data can then be compared to historic data from PEDS to understand changes in soil structure over time. We are currently looking for funding avenues to support these analyses and synthesis. Graduate student Alyssa Duro (UC Riverside) has been developing a method to identify and map in situ distributions of soil macroporosity using a structure-from-motion photogrammetry technique. Alyssa photographed soil profiles in the field from excavations at HJ Andrews along with help from graduate student Victoria Moreno (Oregon State University). The technique will be compared to results from a multistripe laser triangulation (MLT) method and is expected to overcome significant challenges when working in difficult terrain and in soils that contain significant rock and root distributions that make the collection of intact monoliths for MLT impractical. Modeling efforts for HJ Andrews have commenced and have impressively been led by an undergraduate student Shreya Ramesh (Penn State) through her summer REU (2021) and honor's thesis. Efforts thus far have been focused on parameterizing the watershed scale reactive transport model HBV-BioRT to ask the question about how changes in land use (differences in harvesting practices) influence carbon dynamics (see attached AGU posters). A new graduate student Fiona Liu has joined the team FA22. She has been pulling together the rich hydrometeorological data, especially temperature and precipitation, over the past seven decades to analyze temporal trends. Fiona will also continue the HBV-BioRT modeling work where Shreya left. Graduate student Kayalvizhi Sadayappan (Penn State University) has been using discharge, stream chemistry, and groundwater chemistry data to calibrate a watershed reactive transport model that aims to understand the effects of woody encroachment on carbonate weathering rates and water chemistry. Graduate student Kachinga Silwimba is a new PhD student in Boise State's PhD in the Computing-Data Science Emphasis. To date he has been conducting preliminary analysis of a dataset created at the National Center for Atmospheric Research that was developed in support of a global Soil Parameter Model Intercomparison Product (SP-MIP) experiment. He is also beginning to explore a follow-on effort conducted at NCAR, a large perturbed parameter experiment (PPE). Both are runs of the Community Land Model that examine the response of ecohydrologic stores and fluxes in response to perturbations in soil and vegetation parameters. 2) Specific Objectives: Graduate student Victoria Moreno (Oregon State University) quantified water-stable aggregate-size distributions, aggregate arrangements, pore geometry, and soil hydraulic properties at HJA 2021. Her goal is to understand the role of carbon destabilization across variation in land cover and aspect at HJA. Victoria presented her initial findings at SSSA 2022 and is working toward a manuscript. Graduate student Annalise Guthrie (University of Kansas) quantified the propensity for soil organic carbon to become soluble with changes in land use and precipitation, far below the plow line. Her work demonstrates: 1) an enhanced potential for soil organic carbon solubility in agricultural soils, which suggests a greater potential for soil organic carbon loss as CO2, and 2) that changes in soil organic carbon content of soil profiles may induce changes in soil structure. Her work is important given that enhanced release of soluble soil organic carbon increases the likelihood for organic acids to proceed as a weathering agent if able to freely flow through soils. Annalise presented her initial findings at SACNAS 2022and is working with PI Li to develop a reactive transport model to quantify how changes in carbon dynamics influence weathering processes at depth. 3) Significant results: Graduate student Alyssa Duro (UC Riverside) has developed a VisNIR spectroscopy calibration library of over 1000 samples for mapping high-resolution, horizon-scale chemistry of rough soil surfaces. The goal of this work is to be able to map soil chemical constituents at fine-resolution (~180 um) and at an appropriately broad scale to capture the spatial heterogeneity of soil properties that are missed by standard laboratory chemical analysis of bulk point samples. Alyssa's library includes 576 soils collected from NEON sites. Alyssa is currently using this library to develop a topographic correction procedure that accounts for the orientation of each pixel of the surface of collected soil monoliths sampled from each soil horizon to remove the impact of slope and aspect from the spectra and estimate and map soil organic C content. Graduate student Annalise Guthrie (University of Kansas) has analyzed the Pedogenic and Environmental DataSet (PEDS), a continental scale dataset that contains laboratory and field soil morphological data from over 48,000 pedons collected by the USDA Natural Resources Conservation Service (NRCS) - National Cooperative Soil Survey (NCSS). Using this tool she has been exploring B horizons (with mid-horizon depths of 30 to 120 cm) of pedons supporting forested lands with and without Ap horizons. Her results imply that changes in root abundance at depths well below the plow line are the causal agent for altered deep soil structure (e.g., ped size, roundness) at the continental scale. These changes in deep soil structure exhibit rebound toward initial conditions within human timescales with regeneration of secondary forest vegetation. In addition, some soil structural metrics were not exhibiting systematic change with altered rooting abundance across soil orders (e.g., ped elongation and angle) demonstrate that the degree of soil development can interact with the influence of rooting abundance on soil structure. Graduate student Kayalvizhi Sadayappan (Penn State University) has been analyzing the changes in hydrology in N1B and N4D under the same climate change but different extent of woody encroachment. One major finding is that as discharge decreases, an increase in percent of stream flow comes from deeper groundwater. Co-PI Daniel Hirmas worked to develop a method to evaluate dynamic structural changes below-ground using a combination of initial soil monolith scans and soil moisture sensor data. The method will be applied to the coupled monolith and sensor data collected at the proposed sites and allows for dynamic parameterization of a dual porosity model. A complete manuscript draft has been prepared for this method and is currently being revised based on the co-author comments.
Publications
- Type:
Peer Reviewed Journal Articles
Status:
Published
Year Published:
2022
Citation:
Wen, H., Sullivan, P.L., Billings, S., Ajami, H., Cuvea, A., Hirmas, D., Flores, Koop, A., A., Murenbeeld, K., Zhang, X., Li, L. (2022). From Soils to Streams: Connecting Terrestrial Carbon Transformation and Chemical Weathering to Solute Export across Hydrologic Regimes. Water Resources Research. doi: 10.1029/2022WR032314.
- Type:
Peer Reviewed Journal Articles
Status:
Published
Year Published:
2022
Citation:
Sullivan, P.L., Billings, S.A., Hirmas, D., Li, L., Zhang, X., Ziegler, S., Murenbeeld, K., Ajami, H., Guthrie, A., Singha, K. and Gim�nez, D., 2022. Embracing the dynamic nature of soil structure: A paradigm illuminating the role of life in critical zones of the Anthropocene. Earth-Science Reviews, 225(C).
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Guthrie, A.V., Hirmas, D., Sullivan, P.L., Singha, K., Flores, A., Nippert, J., Li, L., Wen, H., and Billings, S. (2022). Evidence for rapid and wide-spread root-induced soil structural changes in response to land use. Goldschmidt, Honolulu, Hawaii.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Duro, A. M., Hirmas, D. R., Ajami, H., Gim�nez, D., Billings, S. A., Sullivan, P. L., Zhang, X., Flores, A., Li, L., & Moreno, V. (2022) Topographic Correction of Proximally Sensed, High Resolution VisNIR Soil Spectra for Horizon-Scale Chemomapping. UC GIS Week, MA.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Hirmas, D. R., Zhang, X., Sullivan, P. L., Ajami, H., Billings, S. A., Sena, M. G., Faria Tavares de Souza, L., Li, L., Pachon, J. C., & Flores, A. (2022) Predicting Rapid Macroporosity and Hydraulic Conductivity Response to Soil Moisture. ASA, CSSA, SSSA International Annual Meeting, Baltimore, MD.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Moreno, V., Sullivan, P. L., Duro, A., Hirmas, D. R., Billings, S. A., Ajami, H., Li, L., Jarecke, K., & Bailey, V. L. (2022) Do Indirect Effects of Forest Stand Age and Aspect Govern SOC Stability Via Their Influence on Soil Aggregate Development? ASA, CSSA, SSSA International Annual Meeting, Baltimore, MD.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Duro, A. M., Hirmas, D. R., Ajami, H., Gim�nez, D., Billings, S. A., Sullivan, P. L., Zhang, X., Flores, A., Li, L., & Moreno, V. (2022) Topographic Correction of Proximally-Sensed, High-Resolution Visnir Soil Spectra for Horizon-Scale Carbon Mapping. ASA, CSSA, SSSA International Annual Meeting, Baltimore, MD.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
??Li, L., Wen, H., Sullivan, P.L., Billings, S. A., Ajami, H. Cueva, A., Flores, A.N., Daniel Hirmas, D., Koop, A.N., Murenbeeld, K.J., & Zhang X. (2022). From Soils to Streams: Connecting Terrestrial Carbon Transformation, Chemical Weathering, and Solute Export Across Hydrological Regimes AGU fall meeting, Chicago, IL.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Sadayappan, K., Keen, R., Moreno, V., Sullivan, P. L., Nippert, J. B., & Li, L. (2022, December). Woody Encroachment increases Evapotranspiration and Groundwater Flow in a Prairie Grassland. AGU fall meeting, Chicago, IL.
|
Progress 03/01/22 to 02/28/23
Outputs
Target Audience:Prompted by the emerging idea that soil fabric is deeply and rapidly responding to climate and land use changes, the proposed work addresses a fundamental question: How dothelife-cycles and arrangements of soil aggregatesmechanistically interact to regulate water flow, carbon cycling, and biogeochemical fluxes from particle to continental scales? To accomplish this goal, we are leveraging existing environmental observatories (e.g., USDA, NSF-funded long-term research sites) and NEON sites, as well as ancillary data (e.g., NRCS Soil Climate Analysis Network and remotely sensed products), that represent gradients of climate, land use, and soil texture to: 1) investigate biotic and abiotic drivers of soil aggregate formation and disintegration, arrangement, and pore geometry through manipulative experiments illuminating the control of binding agents, mineral surface area, and soil depth on these trajectories; 2) quantify how and to what degree aggregate arrangements influence porosity and, thus, water and C fluxes with depth; 3) develop new tools that leverage remotely-sensed surface soil moisture and vegetation properties to predict depth distributions of soil aggregate and related properties; 4) integrate mechanistic understanding of processes from individual aggregate- to pedon-scale into hillslope- to watershed-scale models to project soil biogeochemical responses to changes in soil pore development; and, 5) model the continental-scale effects of changing aggregate life-cycles and arrangements on the biogeochemistry of soil systems and resulting feedbacks to climate. All of the PIs on this project have contributed to this report: Pamela Sullivan, Li Li, Sharon Billings, Hoori Ajami, Daniel Hirmas, and Alejandro Flores. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Our group meets monthly over Zoom to provide cross-disciplinary training of undergraduate, graduate, postdoc, and PIs. The group is roughly 20 individuals of various backgrounds, and we spend the first half of the meeting leading lectures on hydrology, biology, statistics, and modeling. We use the second half of the meeting to discuss how we use those foundational concepts to interpret data and develop numerical models. How have the results been disseminated to communities of interest?Our efforts thus far have been disseminated to scientific communities of interest at conferences such as SSSA, EGU, and AGU in 2023. Billings has integrated information from this project into her Forest Ecosystems class (fall 2023). What do you plan to do during the next reporting period to accomplish the goals? Continue to analyze data from the aggregate turnover experiment Complete the development of the structure-from-motion method for capturing in situ macroporosity distributions Finishing analyzing soils from Reynolds and HJA Start to synthesize controls on aggregate formation, stability, and collapse Continue analyze the PEDS dataset and compare results to the newly-developed NEON dataset Link remotely sensed data to soil properties databases Continue with modeling at HJA and to pull modeling datasets together for Reynolds Creek Create point scale simulations with the Community Land Model at HJA and Reynolds Creek to enable cross comparison with other methods and field efforts. Hold a 2-day workshop on data-centered learning in critical zone science at the Earth Educators Rendezvous in Philadelphia, PA in July 2024.
Impacts
What was accomplished under these goals?
1) Major Activities: H5: Graduate student Kachinga Silwimba is a PhD student in Boise State's PhD in the Computing-Data Science Emphasis. To date he has been conducting preliminary analysis of a dataset created at the National Center for Atmospheric Research that was developed in support of a global Soil Parameter Model Intercomparison Product (SP-MIP) experiment. He is also beginning to explore a follow-on effort conducted at NCAR, a large perturbed parameter experiment (PPE). Both are runs of the Community Land Model that examine the response of ecohydrologic stores and fluxes in response to perturbations in soil and vegetation parameters.? 2) Specific Objectives: quantify the rates of aggregate collapse and formation advance understanding of how modified subsurface structure influences potential for SOC losses finish quantifying soil and root properties at HJ Andrews and Reynolds Creek begin modeling SOC dynamics at HJ Andrews model the impact of woody encroachment on carbonate weathering analyze the Soil Parameters Intercomparison Products 3) Significant results: Graduate student Alyssa Duro (UC Riverside) has revised and submitted her publication on developing a VisNIR spectroscopy calibration library of over 1000 samples for mapping high-resolution, horizon-scale chemistry of rough soil surfaces and the paper is accepted for publication in the Soil Science Society of America Journal. The goal of this work is to be able to map soil chemical constituents at fine-resolution (~180 um) and at an appropriately broad scale to capture the spatial heterogeneity of soil properties that are missed by standard laboratory chemical analysis of bulk point samples (see uploaded SSSA poster and manuscript in press). Alyssa's library includes 576 soils collected from NEON sites. Alyssa used this library and developed a topographic correction procedure that accounts for the orientation of each pixel of the surface of collected soil monoliths sampled from each soil horizon to remove the impact of slope and aspect from the spectra and estimate and map soil organic C content. Graduate student Annalise Guthrie (University of Kansas) has analyzed the Pedogenic and Environmental DataSet (PEDS), a continental scale dataset that contains laboratory and field soil morphological data from over 48,000 pedons collected by the USDA Natural Resources Conservation Service (NRCS) - National Cooperative Soil Survey (NCSS). Using this tool she has defined how B horizons (with mid-horizon depths of 30 to 120 cm) of pedons supporting forested lands - with and without Ap horizons - respond structurally to root regeneration. Her results imply that changes in root abundance at depths well below the plow line are the causal agent for altered deep soil structure (e.g., ped size, roundness) at the continental scale. She specifically highlights the soil orders and land cover types that appear especially susceptible to soil structural change upon land use change, and those that are particularly resilient upon root regeneration. Rebound toward initial structural conditions, in soils where this occurs, appears to happen within human timescales with regeneration of secondary forest vegetation. Guthrie has developed a working draft of this manuscript which we intend to submit in early 2024. Graduate student Lola Klamm's soil incubations (see above) reveal how increasing abundance of a compound comprising microbial cell walls (i.e., a proxy for some of the microbial necromass pool in soils) is positively linked to the formation of large soil aggregates. Her work also demonstrates that this effect is most evident in high clay soils with great overburden pressure, such as we might find deep within B (and especially Bt) soil horizons. Perhaps most intriguingly, her work demonstrates that where C protection is greatest, putative binding agents are far more likely to be used as a microbial C substrate. Caption for when this is pulled off Google Docs: Aggregate size distribution of relatively high-clay soil incubated for ~6 weeks with overburden pressure similar to that of soil ~1 m deep. Prior to the incubation the largest size fraction made up the smallest proportion of each soil sample. NAG refers to the compound added to each soil, a synthetic version of a compound that occurs nationally in microbial cell walls. Klamm et al. in prep. Co-PI Daniel Hirmas worked to develop a method to evaluate dynamic structural changes below-ground using a combination of initial soil monolith scans and soil moisture sensor data. The method will be applied to the coupled monolith and sensor data collected at the proposed sites and allows for dynamic parameterization of a dual porosity model. A complete manuscript draft has been prepared for this method and is currently being revised based on the co-author comments. Dr. Laura Podzikowski, a post-doc at KU funded via a different grant, contributes to this project by working with the NRCS dataset described above. Billings and Podzikowski have demonstrated how increasingly flashy precipitation patterns are linked to less well-developed soil, and how structural attributes in the A horizon can govern development of the B horizon. These features vary with soil order and land cover type. Dr. Zachary Brecheisen, a research fellow at KU funded via other means, works with remote sensing data to investigate how spatial patterns of forest productivity are changing with climate, in an attempt to project how soil attributes may also undergo modification. Ms. Fiona Liu has worked on modeling hydrological and biogeochemical processes at HJ Andrews using BioRT-HBV, particularly focusing on dissolved organic and inorganic carbon and comparing the old growth and young forests W-1 and W-2. She presented her work at the Gordon conference in Catchment Sciences in June 2024. 4) Key outcomes or Other achievements: Graduate student Kayalvizhi Sadayappan (Penn State University) has been analyzing the changes in hydrology in N1B and N4D under the same climate change but different extent of woody encroachment. One major finding is that as discharge decreases, an increase in percent of stream flow comes from deeper groundwater. Former graduate student Ligia Sousa published one of her dissertation chapters which reveals the tremendous depths to which land use change at the surface can extend into the subsurface. Far beneath the plow line, Ligia uncovered soil structural changes that she links to the infiltration of relatively fresh photosynthate from the surface, which appears to occur to a greater extent in agricultural lands. The extent to which this occurs depends on effective precipitation. Former graduate student Aaron Koop published a paper using the PEDS dataset demonstrating the relationship between macroporosity and complexed organic carbon and clay (COCC) at the US continental scale. This work showed the enormous potential of subsoil horizons to accommodate and complex soil organic carbon promoting aggregation and increasing effective porosity and saturated hydraulic conductivity. The Holiday Farm Fire at HJ Andrews occurred in September 2020 in one of our watersheds of study (the second growth WS1). We leverage our knowledge of this site to explore the impacts of the fire on water quality following the fire. This work is being developed into a manuscript that is expected to be submitted by January 2024
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Duro, A. M., Hirmas, D. R., & Ajami, H. (2023) Topographic Correction of Laboratory-Based Visible Near-Infrared Soil Reflectance Spectra. [Abstract]. ASA, CSSA, SSSA International Annual Meeting, St. Louis, MO. https://scisoc.confex.com/scisoc/2023am/meetingapp.cgi/Paper/148262
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Khandelwal, A., Bush, S.A., Redlins, X.C., & Sullivan, P.L. (2023). Relationship between rooting depth and hillslope position in two mountain forest with contrasting rain-snow precipitation regimes. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Sadayappan, K., Keen, R., Jarecke, K.M., Moreno,V., Nippert, J.B., Kirk, M.F., Sullivan, P.L., & Li, L. (2023). Enhanced carbonate weathering in woody encroachment grasslands. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Bonan, L., Springer, M., Xu, T., Nimmo, J, Gimenez, D., Groh, J., Hirmas, D., Singh, N., Wyatt, B.M., Wiekenkamp, I., Sullivan, P.L. (2023). The occurrence of preferential flow based on high-frequency, multi-depth soil moisture observations across diverse ecoclimate regions. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Guthrie, A., Sullivan, P.L., Kirk, M.F., Loecke, T.D., Rice, C.W., Sikes, B.A., Unruh, M., Hirmas, D., Ajami, H., Singha, K., Klamm, L.M., Billings, S.A., Souza, L.F.T. (2023). Surficial soil changes and precipitation patterns interact to govern propagation of deep soil solutes produced by weathering. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Unruh, M., Sullivan, P.L., Hart, S.C., Ajami, H., McDowell, W.H., Chorover, J., Silver, W.L., Lohse, K.A., Gerson, J.R., Yang, Y., Swenson, M., Hirmas, D., Flores, A.N., Guthrie, A., Singha, K. and Billings, S. (2023). How moisture availability Across climate zones, landscapes, and pedons governs soil organic C spatial heterogeneity and transport to deep horizons. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Billings, S., Brecheisen, Z.S., Li. X., Hauser, E., Souza, L.F.T., Sullivan, P.L., Ajami, H., Flores, A.N., Hirmas, D., Li, L., Michaels, T. and Singha, K. (2023). Throughout Earths mountainous terrain, forest productivity responses to aspect in the Anthropocene are migrating. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Sullivan, P.L., Bixby, L., Moreno, V., Jarecke, K., Sadayappan, K., Keen, R.M., Guthrie. A.V., Souza, L.F.T., Hauser, E., Zhang, X., Ajami, H., Barnard, H.R., Billings, S.A., Flores, A.N., Kirk, M.F., Hirmas, D.R., Li, L., Nippert, J.B., and Singha, K. (2023). Constraining the belowground ecohydrologic consequences of land cover change. AGU fall meeting, San Francisco, CA Invited.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Jarecke, K., Keen, R.M., Sadayappan, K., Moreno, V., Li, B., Dumont, M., Hirmas, D.R., Nippert, J.B., Ajami, H., Billings, S.A., Li, L., Flores, A.N., Zhang, X., Singha, K. and Sullivan, P.L. (2023). Impacts of woody encroachment on soil hydrology: Insights from root distribution, soil moisture time series, and electrical resistivity imaging. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Li Li, Bryn Stewart, Devon Kerins, Kayal Sadayappan, Hang Wen, Julia Perdrial, Pamela Sullivan, Holly Barnard, Kenneth Williams, James Shanley. Illuminating the Invisible : Production and Export of Dissolved Carbon From Land to Rivers. AGU fall meeting, San Francisco, CA
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Wyatt, B.M., Li, B., Ajami, H., Araki, R., Crompton, O., Gimenez, D., Groh, J., Hirmas, D.R., Nimmo, J.R., Singh, N. and Spenger, M., Sullivan, P.L. (2023). Utilizing High-Frequency Soil Moisture Measurements for Detection and Prediction of Preferential Flow. ASA, CSSA, SSSA International Annual Meeting. St. Louis, MO.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Varikuti, V., Hirmas, D.R., Ajami, H., Billings, S.A., Flores, A., Li, L., Nippert, J., Pachon, J.C. & Sullivan, P.L. (2023). Influence of Subsurface Boundary Conditions on Soil Physical and Hydrological Properties. In ASA, CSSA, SSSA International Annual Meeting. St. Louis, MO.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Sadayappan, K., Keen, R., Nippert, J., Jarecke, K.M., Sullivan, P.L., Kirk, M., & Li, L. (2023). Drying streams despite a wetter climate in woody-encroached grasslands. Gordon Research Conference: Catchment Science, Andover, NH.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Jarecke, K.M., Singha, K., Nippert, J.B., Moreno, V., Hirmas, D.H., Ajami, H., Pachon, J.C., Keen, R.M., Billings, S., Li, L., Flores, A., Sadayappan, K., Zhang, X., & Sullivan, P.L. (2023). Illuminating soil hydrologic processes in a woody-encroached tallgrass prairie using electrical resistivity imaging and soil moisture data. Eight Interagency Conference on Research in the Watersheds (ICRW8), Corvallis, OR.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Bonan, L., Sprenger, M., Xu, T., Nimmo, J., Ajami, H., Araki, R., Crompton, O., Gimenez, D., Groh, J., Hirmas, D., Singh, N. Wyatt, B., & Sullivan, P.L. (2023). Inferring spatial and temporal drivers of subsurface preferential flow using machine learning based on high-frequency multi-depth soil moisture observations Eight Interagency Conference on Research in the Watersheds (ICRW8), Corvallis, OR.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
*Sullivan, P. L., Moreno, V., Johnson, K. Duro, A., Jarecke, K., Redlins, A., Gregory, R., Barnard, H., Singha, K., Klamm, L., Guthrie, A., Liu, F.S.T., Silwimba, K., Unruch, M., Ajami, H., Billings, S., Flores, A., Hirmas, D., & Li, L., (2023). How will climate and land cover disturbance influence water and carbon cycles in the critical zone? Applying an ecohydrologic perspective toward H.J. Andrews. Eight Interagency Conference on Research in the Watersheds (ICRW8), Corvallis, OR.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
*Sullivan, P. L., Ajami, H., Barnard, H., Billings, S., Flores, A., Hirmas, D., Li, L., Nippert, J., Singha, K., Cueva, A., Duro, A., Gregory, R., Guthrie, A., Hauser, E., Jarecke, K., Johnson, K., Keen, R., Klamm, L., Koop, A., Knapp, A., Liu, F.S.T., Pachon, J., Moreno, V., Sadayappan, K., Silwimba, K., Souza, L., Redlins, A., Unruch, M., Varikuti, V., Wang, L., Wen, H., Zhang, Xi. (2023). How do roots restructure water and carbon dynamics in the critical zone? EGU Annual Assembly, Vienna, Aust.
- Type:
Journal Articles
Status:
Published
Year Published:
2024
Citation:
Duro, A.M., Hirmas, D.R., Ajami, H., Gim�nez, D., Billings, S.A., Zhang, Z., Li, L., Flores, A., Moreno, V., Cao, Xiayoang, C., Guilinger, J., Sullivan, P.L. (2023). Topographic correction of visible near-infrared soil reflectance spectra for high-resolution, horizon-scale soil organic carbon mapping. Soil Science Society of America Journal. https://doi.org/10.1002/saj2.20612
- Type:
Journal Articles
Status:
Published
Year Published:
2023
Citation:
Sadayappan K., Keen, R.M., Jaracke, K., Moreno, V., Nippert, J.B., Kirk M. F., Sullivan, P.L., Li, L. (2023). Drier streams despite a wetter climate in woody-encroached grasslands. Journal of Hydrology. https://doi.org/10.1016/j.jhydrol.2023.130388.
- Type:
Journal Articles
Status:
Published
Year Published:
2023
Citation:
Souza L.F.T, Hirmas, D.H., Sullivan, P.L., Reuman, D.C., Kirk, M.F., Li, L. Ajami, H., Wen, H., Sarto, M.V.M., Loecke, T.D., Ruick, A.K., Rice, C.W., Billings, S.A. (2023). Root distributions, precipitation, and soil structure converge to govern soil organic carbon depth distributions. Geoderma. doi: 10.1016/j.geoderma.2023.116569.
- Type:
Journal Articles
Status:
Published
Year Published:
2023
Citation:
Koop, A., Hirmas, D., Billings, S.A., Li, L., Cueva, A., Zhang, X., Nemes, A., Sousa, L.F.T., Ajami, H., Flores, A.N., Rudick, A.K., Guthrie, A., Klama, LM., Unruch, M., & Sullivan, P.L. (2023). Is macroporosity controlled by complexed clay and soil organic carbon? Geoderma. doi: 10.1016/j.geoderma.2023.116565.
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Progress 03/01/21 to 02/28/22
Outputs
Target Audience:Audiences at conferences Students in class taught by Flores in the Fall2021 semester Changes/Problems:Recruiting a PhD student took longer than anticipated, in part, due to COVID-19 related delays. Additionally some CLM tutorials that are typically held in summer and winter were postponed this year because of COVID-19, reducing the number of opportunities for the doctoral student to obtain training in running CLM. These have been ameliorated through new materials that have been developed and shared by the CLM maintainers at NCAR. What opportunities for training and professional development has the project provided?Doctoral student Kachinga Silwimba has developed computational skills and exposure to land model data via formal training workshops and informal work with PhD students Doctoral student Silwimba participated in the Winter Land Model Working Group meeting, a small workshop event that highlights recent and ongoing developments to and scientific uses of the Community Land Model. PI Flores was invited to participate in NCAR's Climate and Global Dynamics Advisory Committee, an external board of experts that helps inform the development of the Community Earth System Model, which contains the Community Land Model. Doctoral student Silwimba has participated in professional development and networking activities offered through the Graduate College, PhD Computing Program, and Department of Geoscience at Boise State. How have the results been disseminated to communities of interest?Thus far results have primarily been disseminated to communities of interest via conference and workshop presentations. We do not yet have results from the numerical experiments, although we anticipate developing a manuscript summarizing results of analysis of existing simulation data with the CLM model in 2022. Additionally, some of the insights gleaned from the broader project have influenced PI Flores' graduate course, Modeling Earth and Environmental Systems. In particular, students design and perform numerical experiments using simple models that examine the impacts of climate change to carbon stores in the land surface and thawing of permafrost. Example Jupyter Notebooks can be found here: https://github.com/LejoFlores/Earth-and-Environmental-Systems-Modeling/blob/main/mod02/mod02-CarbonModel-Assignment.ipynb https://github.com/LejoFlores/Earth-and-Environmental-Systems-Modeling/blob/main/mod03/mod03_1D-Diffusion-ExplicitExample.ipynb What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period we will: Select sites for point-scale runs with the CLM model Conduct preliminary numerical experiments at point scales, compare to available observational data, and compare across numerical experiments Leverage existing numerical experiment datasets to explore sensitivities of global land hydrologic and carbon balance simulations to changes in soil parameters. Begin developing manuscripts summarizing research outcomes.
Impacts
What was accomplished under these goals?
To accomplish these objectives we have: Obtained access to a previously conducted set of numerical experiments that examine the sensitivity of global land surface hydrology to soil parameters using the Community Land Model (CLM). These experiments were conducted by colleagues at the National Center for Atmospheric Research (NCAR) under the auspices of the Soil Parameter Model Intercomparison Project (SP-MIP) Developed computational workflows to compare numerical experiments with CLM and understand spatiotemporal differences in the context of principal components/empirical orthogonal functions The graduate student working on the project has started knowledge and skill development around the latest version of CLM in preparation for setting up and running experiments Liaised with colleagues at NCAR about new and ongoing numerical experiments from which our work may also benefit and to which our proposed experiments will also contribute. Conducted exploratory analysis of SP-MIP dataset to characterize how differences in soil texture influence key hydrologic variables like soil moisture, runoff, and evapotranspiration at continental scales. Conducting literature reviews and developing an annotated bibliography to document relevant literature on soil parameter sensitivity in global models.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2022
Citation:
Sullivan, P.L., Billings, S.A., Hirmas, D., Li, L. Zhang, X., Ziegler, S., Murenbeeld, K., Ajami, H., Guthrie, A., Singha, K., Gimenez, D., Duro, A., Moreno, V., Flores, A., Cueva, A., Koop, A., Aronson, E., Barnard, H., Banwart, S., Keen, R., Nemes, A., Nikolaidis, N., Nippert, J., Richter, D., Robinson, D.A., Sadayappan, K., Souza, L.F.T. de, Unruh, M., Wen, H. 2022. Embracing the dynamic nature of soil structure: A paradigm illuminating the role of life in critical zones of the Anthropocene. Earth-Science Reviews 225, 103873, doi:10.1016/j.earscirev.2021.103873.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Billings, S.A., Sullivan, P.L., Hirmas, D., Guthrie, A., Souza, L.F.T. de, Hauser, E., Zhang, X., Wen, H., Li, L., Richter, D., Aronson, E.L., Ajami, H., Barnard, H.R., Nippert, J.B., Singha, K., Flores, A.N., Bixby, L. Roots as agents of rapid soil structural change in the Anthropocene. Annual meeting of the American Geophysical Union. December, 2021.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Hirmas, D., Zhang, X., Sullivan, P., Billings, S.A., Souza, L., Li, L, Ajami, H., Sena, M.G., Flores, A.N. A novel method for predicting rapid changes in soil structure and hydraulic conductivity. Annual meeting of the American Geophysical Union. December, 2021.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Wen, H., Sullivan, P., Billings, S.A., Ajami, H., Cueva, A., Flores, A.N., Hirmas, D., Koop, A.N., Murenbeeld, K.J., Zhang, X., Li, L. The predominant control of hydroclimatic conditions on carbon and weathering fluxes at the hillslope scale. Annual meeting of the American Geophysical Union. December, 2021.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Sullivan, P.L., Billings, S.A., Hirmas, D., Li, L., Ajami, H., Flores, A., Singha, K., Nippert, J., Barnard, H., Hauser, E., Koop, A., Zhang, X., Murenbeeld, K. When and where do top-down processes govern critical zone structure and feedback to govern climate? Annual meeting of the American Geophysical Union. December, 2021.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Duro, A.M., Hirmas, D., Ajami, H., Gimenez, D., Billings, S.A., Sullivan, P.L., Zhang, X., Li, L., Flores, A. The slope and aspect of a soil surface impact a discernible influence on the spectral signature collected by hyperspectral imaging spectroscopy. Annual meeting of the Soil Science Society of America. November, 2021.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2021
Citation:
Sullivan, P.L., Billings, S.A., Li, L., Hirmas, D., Nippert, J., Barnard, H., Singha, K., Ajami, H., Flores, A., Murenbeeld, K., Wen, H., Koop, A., Sadayappan, K., Keen, R., Zhang, X. Do root-regolith-rock interactions govern critical zone-climate feedbacks over decades to centuries? Goldschmidt conference. July, 2021.
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