Spatio-temporal Isotope Analytics Lab (Spatial)
Professor Gabriel Bowen
University of Utah - Department of Geology & Geophysics







Current Projects

Project "FIND" - Forensic Isoscapes, New Directions (Phase I supported by the Henrey Jackson Foundation, 1/1/19 - 6/30/20)

Leveraging NEON to Build a Predictive Cross-scale Theory of Ecosystem Transpiration (supported by NSF, 8/15/18 - 7/31/22)

Water is a critical resource that sustains continental ecosystems. Land plants play a critical role in the cycling of water between the continents and atmosphere by extracting water from soils and groundwater and releasing it to the atmosphere as they grow. Existing data suggest that this process, transpiration, accounts for more than half of the global transfer of water from the continents to the atmosphere. Surprisingly little is known about how much water is transpired, how different types of plants and ecosystems govern transpiration, and how properties of ecosystems are shaped by transpiration. This award supports an interdisciplinary group of ecologists, Earth and atmospheric scientists, and engineers to make estimates of plant transpiration across the United States for the first time and use these data to develop models and improve predictions of future plant water use. The team will develop new techniques and datasets benefitting the scientific community and conduct interdisciplinary graduate student training to prepare diverse, next-generation scientists to tackle ecological and data science challenges.

The project team will work with a wide range of data products produced by the National Ecological Observatory Network, with a primary emphasis on stable isotope ratios of water vapor and carbon dioxide. Isotope ratios provide an integrated measure of physical processes controlling gas exchange between plant leaves and the atmosphere. The suite of sensors deployed by the Network across the USA provides the first standardized dataset enabling isotope-based estimation of transpiration across a diverse range of continental ecosystems. The project team will develop new calibration procedures and data products from the Network's sensor data and distribute these for use by the broader research community. These data will be integrated with other data collected by the Network and information from field campaigns by the project team, using analysis at a range of spatial scales from individual plots to continental scales to determine how ecosystem structure and plant regulation of gas exchange control transpiration. This knowledge will be integrated into and used to test models for plant water use that reflect the underlying distribution of functional traits and structural properties within the study ecosystem. The models will be used to examine the potential sensitivities of transpiration and ecosystem water use. During the course of its work, the project will develop and disseminate new measurement and data analysis approaches and datasets of broad use to researchers, and will support a graduate short course in spatial sciences.

IsoBank: A Centralized Repository for Isotopic Data (supported by NSF, 8/1/18 - 7/31/21)

Stable isotopes encode and integrate the origin of matter; their analysis offers tremendous potential to address questions across diverse scientific disciplines. The broad applicability of stable isotopes, coupled with advancements in high-throughput analysis, have created a scientific field that is growing exponentially, and generating data at a rate paralleling the explosive rise of DNA sequencing and genomics. Centralized data repositories, such as GenBank, have become central in archiving information, and the analytics offered by these resources are revolutionizing science and everyday life. But to date, a centralized database for the management of isotopic data does not exist. The absence of such a resource has impeded research progress through the unnecessary duplication of effort, restricted the near-boundless application of stable isotopes, and curtailed the exchange of information among scientists within and among disciplines. The creation of a centralized database for stable isotopes would be more than a silo for data; it would be a dynamic resource to unite disciplinary fields and answer pressing questions in agriculture, animal sciences, archaeology, anthropology, ecology, medicine, nutrition, physiology, paleontology, forensics, earth and planetary sciences. We believe that such a centralized database would accelerate and enhance such global and multi-disciplinary endeavors, thus broaden the reach of isotope science.

This project brings together a multidisciplinary team of analytical experts and scientists who produce and interpret isotope data with database architects and website developers in a series of workshops that will culminate in the creation of an IsoBank, a web-accessible centralized database of stable isotope data that serves an interdisciplinary research and education community. IsoBank will enable a diverse and rapidly growing scientific community to harness the advantages of big data analytics. At the same time, it will increase the efficiency of a wide range of existing isotope-based applications, which require reference data to support interpretation. IsoBank is envisioned to foster interactions across disciplines that speak a common chemical language that will result in the fusion of diverse perspectives, a process that has resulted in some of the biggest and most creative advances in science. IsoBank will enhance the standards for data quality assurance and control by creating a network among core isotope laboratories in the U.S. that are currently producing nearly a million new datapoints per year. Lastly, IsoBank (isobank.org) is poised to address growing initiatives of publication and funding agencies for data accessibility and transparency.

ORIGIN: Origin Inference from Geospatial Isotope Networks (supported by NSF, 8/1/16 - 7/31/20)

Long-distance migration is a unique and important behavior with widespread implications for environmental and ecological systems. Animals face direct threats during migration ranging from severe nutritional stress to potential interactions with wind farms and other anthropogenic hazards. Migration links the geographic endpoints of an animal?s life cycle, and patterns of migration determine where and when animals are dependent on habitats that may be threatened or experiencing change due to human activities. Pathways of migration represent potential transmission paths for diseases, parasites, and nutrients carried by migrants. Despite the long-recognized significance of migration, detailed information on migration patterns for most animals is remarkably limited. The field of migration research is poised for major advances due to the development of new technologies and the potential to combine different types of data providing complementary information on animal migration. The ORIGIN project will represent a collaboration between biologists, geochemists, and computer scientists to develop software and database resources allowing researchers to take advantage of one particularly powerful method of reconstructing migration patterns - the use of natural chemical signals preserved in the body tissues of migrants. In the course of this research the ORIGIN team will develop new statistical approaches that are widely useful to scientists and will provide novel interdisciplinary training to graduate students and research opportunities for undergraduates from STEM-underrepresented groups.

The goal of the ORIGIN project is to develop data and analytical resources that facilitate major advances in understanding of ecological, evolutionary, physiological, and biogeochemical dimensions of animal migration by increasing the use and standardization of isotope-enabled migration research methods. ORIGIN will consist of two integrated platforms that together provide the data resources, analytical tools, and project support necessary to streamline the analysis of data from migratory animal samples. First, updates to the IsoMAP web-GIS platform will enhance its ability to provide timely, authoritative, and comprehensive map data products and models describing patterns of isotopic variation in the environment. Second, these products will be used by a new package developed for the R programming environment that will provide an accessible but flexible suite of tools supporting 1) analysis of isotopic and non-isotopic data to evaluate the migratory origin of individuals, including two distinct Bayesian approaches for integration of data from multiple makers, 2) planning of isotope-enabled migration research projects, and 3) generation of analytics for assessment of statistical assignment results. ORIGIN will develop infrastructure that will support a wide range of scientific communities, and will support training and scientific outreach programs including a graduate short course in spatial sciences and human migration-focused research opportunities for undergraduates from STEM-underrepresented groups. Project results will be disseminated at http://isomap.org.

P-E Land-C: Terrestrial Mediation of Carbon Cycle Response Through the Paleocene-Eocene Thermal Maximum (supported by NSF, 7/1/15 - 6/30/19)

This award to the University of Utah will support field, laboratory, and modeling studies to constrain the role of terrestrial biogeochemical change in modulating the environmental and climatic evolution of the Paleocene-Eocene thermal maximum (PETM). The PETM is a well-documented geological episode of carbon-cycle induced global change that had major repercussions on Earth's environmental and biotic systems. Although a general understanding of the causes and nature of PETM change has been established, a number of anomalous characteristics of the event, including its long duration, high apparent climate sensitivity, and rapid termination, remain unexplained. This project will determine whether changes in the terrestrial critical zone, including carbon storage in land plants and soils, formation of inorganic soil carbonate, and burial of organic and inorganic carbon in continental sedimentary rocks, occurred during the PETM and contributed to the pattern of global change observed during the event. Field studies and lab analyses will document critical zone carbon storage changes at sites in the western USA and Spain and reconstruct local environmental conditions that accompanied these changes. New computer model components will be developed and applied to evaluate the degree to which the observed changes were globally significant and the patterns of global climatic and carbon cycle change that they would have induced, thus providing a more comprehensive understanding of the PETM event. This new information will be incorporated in educational materials, targeted at the graduate, undergraduate, and high-school levels, that communicate the role of the carbon cycle coupled Earth system change over geological and human timescales.

Continental ecosystems store a vast amount of carbon, which is potentially easily transferred to or taken up from the atmosphere, affecting global climate. The response of these systems to global change represents a major source of uncertainty in projections of future environmental conditions, as well as a fundamental unknown in our understanding of the geological record of past climate. This work will test ideas about how carbon storage changes as global climate warms, developed based on the study of modern ecosystems, through a focused study of one of the best-documented episodes of rapid climatic warming in the geologic record. The results will improve our understanding of the role of terrestrial carbon cycle feedback as a mediator of global change, advancing our ability to interpret the paleoclimate record and project future changes in Earth's climate.

Previous Projects

Inter-university Training for Continental-scale Ecology (ITCE) - Bridging Scales and Systems with Isotopes (supported by NSF, 2/1/12 - 1/31/17)

Providing innovative approaches in graduate and postdoctoral training that encompass emerging opportunities in continental ecology is the critical focus of this project. Thirty-two faculty from nearly two dozen universities will combine efforts to develop such a training program that addresses ecological challenges at regional to continental scales. The approach will include the integration of stable isotopes with other datasets and computer models. Stable isotopes play a critical role in evaluating scalable temporal and spatial data streams and allow underlying processes and patterns to be identified and quantified across scales of space and time. Key themes to be addressed include gas exchange between ecosystems and the atmosphere, animal migration, ecohydrology, and pathways of photosynthesis and consequences for animal diets. 

The project includes four elements of training across the participating universities: (1) multidisciplinary and multi-university instruction through two week lecture and laboratory courses, with the first focusing on principles and practices and the second on linking isotopes, processes and patterns, modeling, and scaling; (2) extended hands on training after the courses, where graduate students will obtain additional training and expand their theses through visits and collaborations with course instructors at other universities; (3) inter-university postdoctoral training, focusing on modeling and syntheses across the thematic research areas of migration, carbon cycle, water cycle, and disturbance; and (4) developing, integrating, and disseminating over the web databases, data analysis tools, and training modules to be used by others. Training of cohorts will be sustained through workshops in advance of major scientific meetings and participation with postdocs at the host institutions. Students will also organize sessions at national meetings as a component of their professional development.

Bighorn Basin coring project (BBCP) – Targeted continental drilling of Paleogene hyperthermals (supported by NSF, 10/1/10 - 9/30/14)

Despite their relevance to current anthropogenic changes in the coupled carbon-climate system, the cause(s) and consequences of repeated hyperthermal events documented in early Paleogene climate records remain poorly understood. Research on continental records of hyperthermals has lagged the marine community largely because of the time-consuming nature of outcrop studies and the obscuring effects of surface weathering. We are working as part of a collaborative, multi-institution team that in 2011 will collect ~600 meters of core from three sites in the Bighorn Basin, where rapid accumulation of fluvial and floodplain overbank sediments preserved thick sections spanning the Paleocene-Eocene thermal maximum and “ELMO” events. These new cores will provide unprecedented opportunities for high-resolution sampling of unweathered sediments to assess the geochemical, isotopic, and biological expression of hyperthermal events in these continental rocks. Our group will focus on stable isotope stratigraphy of organics and authigenic carbonate preserved in overbank deposits, providing master chemostratigraphic records supporting the correlation of the drill cores to the global timescale and providing opportunities to investigate paleoclimatic, paleoecological, and paleo-pCO2 changes through the hyperthermals.

Linking coastal terrestrial ecosystems and eustatic sea-level changes: A case study in the Tornillo Group, Big Bend National Park, TX (supported by ACS-PRF, 9/1/2012 - 8/31/2014)

Understanding the sensitivity of coastal environments to sea-level change is important for both reconstructing impacts of past eustatic sea-level changes and predicting the evolution of coastal ecosystems in response to future sea-level rise. Although sequence stratigraphic records constraining sea-level changes throughout Earth’s history are now abundant, more work is needed to combine these records with other disciplines to improve models for coastal environmental dynamics. Fluvial system dynamics in coastal settings are strongly affected by eustatic sea-level change, and linking these processes to changes in vegetation distribution and biogeochemical processes could lead to novel and sensitive chemostratigraphic tools for reconstructing sea-level influences on coastal ecosystems. We propose to test two hypotheses relating to the expression of sea level cycles in deposits of the Tornillo Group (Big Bend National Park). First, we will test the idea that the sedimentological and biogeochemical expression of eustatic cycles can be traced along a coast-to-continent gradient. We will generate new lithological and carbon isotope records for two outcrops of the Tornillo Group located at different distance of the paleoshoreline and compare their sequence stratigraphic records. Second, we will test the hypothesis that paleo-ecological and biogeochemical changes at these sites are linked to eustatic sea level cycles through variation in pedogenesis and vegetation dynamics. The outcomes of this work will impact the research community’s ability to use chemostratigraphy for cyclostratigraphic correlation in coastal systems and will improve our understanding of links between eustatic sea level change and terrestrial ecology and biogeochemistry over millennial timescales.

Integrating proxies and Earth system models to elucidate water cycle dynamics: Did global warming cause an enhanced hydrological cycle in the Eocene? (supported by NSF, 8/1/09 - 7/31/2013)

The early Eocene climate was characterized by repeated fluctuations between warm and hyperthermal climate conditions superimposed on a gradual warming trend that culminated in the Eocene Thermal Maximum. We are using a number of isotopic and sedimentological proxies to reconstruct how global patterns of aridity and moisture varied in associated with these climate transitions. Data on climatic wetness from continental sections in North America, Asia, and South America will be integrated with marginal marine records (Mark Pagani, Yale University) documenting runoff to develop a picture of the spatial structure of the atmospheric water cycle and identify differences between warm and hyperthermal climate states. These will be compared with fully coupled GCM simulations (Matt Huber, Purdue) of the Eocene climate to identify robust features of the modeled water cycle and test the large-scale dynamics of the model reconstructions. The resulting synthesis will lead to an improved understanding of the dynamics and impacts of early Paleogene climates and also test predicted large-scale changes in the future water cycle against data from the geological record of greenhouse climates.

Hydrological controls on nitrogen dynamics in artificially drained agricultural watersheds (supported by the Ralph W. and Grace M. Showalter Research Trust Fund, 7/1/10 – 6/30/12)

Subsurface (‘tile’) drainage, consisting of buried grids of perforated pipe, may accelerate the loss of nitrogen (N) and other pollutants by altering pathways and rates of soil water and groundwater through agricultural lands. We have established a hydrological monitoring network at the Animal Science Research and Education Center to quantify the contribution soil water and groundwater to N transport in tile drainage. Physical, chemical, and isotopic data will be collected from tile drainage, precipitation, groundwater, and soil water to develop a geochemical mixing model that partitions the components of subsurface soil water and groundwater in tile drainage. A mechanistic synthesis of tile drainage will be developed that relates the relative contributions of these hydrological components to precipitation amount, antecedent hydrology, and N fertilizer applications practices. The resulting synthesis will be used to ‘scale-up’ to large-scale watersheds (e.g., Wabash River) and to inform land management decisions.

The Isotope Networks Portal: Data Integration for Biogeochemistry and Ecology Through Web-based Geospatial Modeling. (supported by NSF, 8/1/2008 - 7/31/2012)

A new organizational model for data-driven science is emerging and may support generation of large data sets for environmental and ecological parameters at numerous sites across the U.S. , perhaps the globe. These data will provide uniformity in measurement types and methods and public data availability, enabling unique research opportunities through providing data for simultaneous study of equivalent systems at numerous spatially distributed sites. A primary challenge facing scientific consumers of this data is that no common framework exists for accessing and integrating this data with a diverse array of other data sources and models needed to apply the data to biological research questions. The IREH group is developing a collaborative effort to produce a web-based GIS portal, INPort (Isotope Networks Portal), that will provide a transparent interface between data consumers and data sources via integrated data querying, data acquisition, and geospatial modeling operations. Users will interact with INPort through a map-based interface that will allow spatiotemporal domain and model selection and parameter specification. INPort software will conduct data identification, acquisition, and processing and model execution behind the scenes while allowing the user to monitor the project status. Model output and documentation will be provided as live, interactive GIS data layers for display and manipulation within INPort or user download. In total, INPort will provide a seamless environment for integrated data/model exploration, visualization, and hypothesis testing.

Holocene water balance of the northeastern Great Basin (supported by NSF, 9/15/06 - 8/31/11)

In many parts of the world, water is a limiting resource for plants, animals, and humans. For arid regions such as the southwestern United states , understanding variability in the availability of water is critical to forecasting and planning for the risks associated with population growth and urban development. This understanding must include an understanding of natural levels of variability in water balance (precipitation - evaporation). The IREH group is working to generate records documenting the last ~8,000 years of water cycle history as recorded in the sediments of the Great Salt Lake . This time interval includes several well-documented warm- and cool-climate intervals, allowing us to investigate the response of the water cycle to climate change. The records, based on the isotope geochemistry of organic biomarkers, will let us probe the Holocene water cycle of this arid part of the western U.S. for prolonged intervals of dry and wet climate, and improve our understanding of when and why these intervals occurred. As a component of the project, we are also calibrating new proxies for water cycle reconstruction based on the organic fossils of brine shrimp.

Dynamics of carbon release and sequestration: Case studies of two early Eocene hyperthermals (supported by NSF, 9/15/06 - 8/31/09)


Geology & Geophysics
Fredrick Albert Sutton Building
115 S 1460 E
Salt Lake City, UT 84112
801-585-7925 gabe.bowen@utah.edu
University of Utah