Katherine Ransom (Former Employee)
Science and Products
Filter Total Items: 15
A hybrid machine learning model to predict and visualize nitrate concentration throughout the Central Valley aquifer, California, USA A hybrid machine learning model to predict and visualize nitrate concentration throughout the Central Valley aquifer, California, USA
Intense demand for water in the Central Valley of California and related increases in groundwater nitrate concentration threaten the sustainability of the groundwater resource. To assess contamination risk in the region, we developed a hybrid, non-linear, machine learning model within a statistical learning framework to predict nitrate contamination of groundwater to depths of...
Authors
Katherine M. Ransom, Bernard T. Nolan, Jonathan A. Traum, Claudia C. Faunt, Andrew M. Bell, Jo Ann M. Gronberg, David C. Wheeler, Celia Zamora, Bryant C. Jurgens, Gregory E. Schwarz, Kenneth Belitz, Sandra M. Eberts, George Kourakos, Thomas Harter
Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers
Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each...
Authors
Katherine M Ransom, Mark N. Grote, Amanda Deinhart, Gary Eppich, Carol Kendall, Matthew E. Sanborn, A. Kate Sounders, Joshua Wimpenny, Qing-zhu Yin, Megan B. Young, Thomas Harter
Fecal indicator and pathogenic bacteria and their antibiotic resistance in alluvial groundwater of an irrigated agricultural region with dairies Fecal indicator and pathogenic bacteria and their antibiotic resistance in alluvial groundwater of an irrigated agricultural region with dairies
Surveys of microbiological groundwater quality were conducted in a region with intensive animal agriculture in California, USA. The survey included monitoring and domestic wells in eight concentrated animal feeding operations (CAFOs) and 200 small (domestic and community supply district) supply wells across the region. Campylobacter was not detected in groundwater, whereas Escherichia...
Authors
Xunde Li, Edward R. Atwill, Elizabeth Antaki, Olin Applegate, Brian A. Bergamaschi, Ronald F. Bond, Jennifer T. Chase, Katherine M Ransom, William B. Samuels, Naoko Watanabe, Thomas Harter
Non-USGS Publications**
Andy Canion, Katherine M. Ransom, Brian G. Katz; Discrimination of Nitrogen Sources in Karst Spring Contributing Areas Using a Bayesian Isotope Mixing Model and Wastewater Tracers (Florida, USA). Environmental and Engineering Geoscience ; 26 (3): 291–311. doi: https://doi.org/10.2113/EEG-2310
Ransom, K. M., Bell, A. M., Barber, Q. E., Kourakos, G., and Harter, T.: A Bayesian approach to infer nitrogen loading rates from crop and land-use types surrounding private wells in the Central Valley, California, Hydrol. Earth Syst. Sci., 22, 2739–2758, https://doi.org/10.5194/hess-22-2739-2018, 2018
Willmes M, Ransom KM, Lewis LS, Denney CT, Glessner JJG, Hobbs JA (2018) IsoFishR: An application for reproducible data reduction and analysis of strontium isotope ratios (87Sr/86Sr) obtained via laser-ablation MC-ICP-MS. PLoS ONE 13(9): e0204519. https://doi.org/10.1371/journal.pone.0204519
Ransom, K. M., et al. (2016), Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers, Water Resour. Res., 52, 5577– 5597, doi:10.1002/2015WR018523.
Li, X., Atwill, E.R., Antaki, E., Applegate, O., Bergamaschi, B., Bond, R.F., Chase, J., Ransom, K.M., Samuels, W., Watanabe, N. and Harter, T. (2015), Fecal Indicator and Pathogenic Bacteria and Their Antibiotic Resistance in Alluvial Groundwater of an Irrigated Agricultural Region with Dairies. J. Environ. Qual., 44: 1435-1447. https://doi.org/10.2134/jeq2015.03.0139
K.M. Lockhart, A.M. King, T. Harter,
Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production, Journal of Contaminant Hydrology, Volume 151, 2013, Pages 140-154, ISSN 0169-7722, https://doi.org/10.1016/j.jconhyd.2013.05.008.
Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production, Journal of Contaminant Hydrology, Volume 151, 2013, Pages 140-154, ISSN 0169-7722, https://doi.org/10.1016/j.jconhyd.2013.05.008.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 15
A hybrid machine learning model to predict and visualize nitrate concentration throughout the Central Valley aquifer, California, USA A hybrid machine learning model to predict and visualize nitrate concentration throughout the Central Valley aquifer, California, USA
Intense demand for water in the Central Valley of California and related increases in groundwater nitrate concentration threaten the sustainability of the groundwater resource. To assess contamination risk in the region, we developed a hybrid, non-linear, machine learning model within a statistical learning framework to predict nitrate contamination of groundwater to depths of...
Authors
Katherine M. Ransom, Bernard T. Nolan, Jonathan A. Traum, Claudia C. Faunt, Andrew M. Bell, Jo Ann M. Gronberg, David C. Wheeler, Celia Zamora, Bryant C. Jurgens, Gregory E. Schwarz, Kenneth Belitz, Sandra M. Eberts, George Kourakos, Thomas Harter
Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers
Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each...
Authors
Katherine M Ransom, Mark N. Grote, Amanda Deinhart, Gary Eppich, Carol Kendall, Matthew E. Sanborn, A. Kate Sounders, Joshua Wimpenny, Qing-zhu Yin, Megan B. Young, Thomas Harter
Fecal indicator and pathogenic bacteria and their antibiotic resistance in alluvial groundwater of an irrigated agricultural region with dairies Fecal indicator and pathogenic bacteria and their antibiotic resistance in alluvial groundwater of an irrigated agricultural region with dairies
Surveys of microbiological groundwater quality were conducted in a region with intensive animal agriculture in California, USA. The survey included monitoring and domestic wells in eight concentrated animal feeding operations (CAFOs) and 200 small (domestic and community supply district) supply wells across the region. Campylobacter was not detected in groundwater, whereas Escherichia...
Authors
Xunde Li, Edward R. Atwill, Elizabeth Antaki, Olin Applegate, Brian A. Bergamaschi, Ronald F. Bond, Jennifer T. Chase, Katherine M Ransom, William B. Samuels, Naoko Watanabe, Thomas Harter
Non-USGS Publications**
Andy Canion, Katherine M. Ransom, Brian G. Katz; Discrimination of Nitrogen Sources in Karst Spring Contributing Areas Using a Bayesian Isotope Mixing Model and Wastewater Tracers (Florida, USA). Environmental and Engineering Geoscience ; 26 (3): 291–311. doi: https://doi.org/10.2113/EEG-2310
Ransom, K. M., Bell, A. M., Barber, Q. E., Kourakos, G., and Harter, T.: A Bayesian approach to infer nitrogen loading rates from crop and land-use types surrounding private wells in the Central Valley, California, Hydrol. Earth Syst. Sci., 22, 2739–2758, https://doi.org/10.5194/hess-22-2739-2018, 2018
Willmes M, Ransom KM, Lewis LS, Denney CT, Glessner JJG, Hobbs JA (2018) IsoFishR: An application for reproducible data reduction and analysis of strontium isotope ratios (87Sr/86Sr) obtained via laser-ablation MC-ICP-MS. PLoS ONE 13(9): e0204519. https://doi.org/10.1371/journal.pone.0204519
Ransom, K. M., et al. (2016), Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers, Water Resour. Res., 52, 5577– 5597, doi:10.1002/2015WR018523.
Li, X., Atwill, E.R., Antaki, E., Applegate, O., Bergamaschi, B., Bond, R.F., Chase, J., Ransom, K.M., Samuels, W., Watanabe, N. and Harter, T. (2015), Fecal Indicator and Pathogenic Bacteria and Their Antibiotic Resistance in Alluvial Groundwater of an Irrigated Agricultural Region with Dairies. J. Environ. Qual., 44: 1435-1447. https://doi.org/10.2134/jeq2015.03.0139
K.M. Lockhart, A.M. King, T. Harter,
Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production, Journal of Contaminant Hydrology, Volume 151, 2013, Pages 140-154, ISSN 0169-7722, https://doi.org/10.1016/j.jconhyd.2013.05.008.
Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production, Journal of Contaminant Hydrology, Volume 151, 2013, Pages 140-154, ISSN 0169-7722, https://doi.org/10.1016/j.jconhyd.2013.05.008.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.