Publications

Please email (rryals@ucmerced.edu) with requests for reprints or preprints.

  1. Bischak, E, S.C. Fusi, J. Jeliazovski, K. Beheshtian, R. Ryals. 2024. Urine-enriched biochar: Coupling sustainability in sanitation and agriculture. Elementa: Science of the Anthropocene. 12:1. DOI: 10.1525/elementa.2022.00118
  2. Harrison, B.P., Z. Moo, E. Perez-Agredano, S. Gao, X. Zhang, R. Ryals. 2024. Biochar-composting substantially reduces methane and air pollutant emissions from dairy manure. Environmental Research Letters. DOI: 10.1088/1748-9326/ad1ad2
  3. Villa, Y., E. Phosalath, R. Ryals. 2024. Carbon persistence of soils with long-term biosolids amendments in California agroecosystems. Soil Science Society of America Journal. 1-17. DOI: 10.1002/saj2.20632
  4. Harrison, B.P., S. Gao, T. Thao, M.L. Gonzalez, K. Williams, N. Scott, L. Hale, T. Ghezzehei, G. Diaz, R. Ryals. 2023. Methane and nitrous oxide emissions during biochar-composting are driven by biochar application rate and aggregate formation. Global Change Biology-Bioenergy. DOI: 10.1111/gcbb.13121
  5. Thao, T., B.P. Harrison, S. Gao, R. Ryals, R. Dahlquist-Willard, G. Diaz, T.A. Ghezzehei, 2023. The effects of different biochar-dairy manure co-composts on soil moisture and nutrients retention, greenhouse gas emissions, and tomato productivity: Observations from a soil column experiment. Agrosystems, Geosciences & Environment. 6:e20408. DOI: 10.1002/agg2.20408.
  6. Hicks Pries, C., R. Ryals, B. Zhu, K. Min, A. Cooper**, S. Goldsmith, J. Pett-Ridge, M. Torn, A.A. Berhe, 2023 (in press). The deep soil organic response to global change. Annual Review of Ecology, Evolution, and Systematics.
  7. Malone, Z.**, A.A. Berhe, R. Ryals. 2023. Impacts of organic matter amendments on urban soil carbon and soil quality: A meta-analysis. Journal of Cleaner Production. 419:138148. DOI: 10.1016/j.jclepro.2023.138148.
  8. Kutos, S., E. Stricker, A. Cooper**, J. Creque, M. Machmuller, R. Ryals, M.E. Kroeger, W.L. Silver. 2023. Utilizing compost to enhance carbon sequestration in rangelands. Journal of Soil and Water Conservation. DOI: 10.2489/jswc.2023.00072
  9. Gao, Si, B.P. Harrison, T. Thao, M. Gonzalez, D. An, T.A. Ghezzehei, G. Diaz, R.Ryals. 2023. Biochar co-compost improves nitrogen retention and reduces carbon emissions in a winter wheat cropping system. Global Change Biology-Bioenergy. DOI: 10.1111/gcbb.13028
  10. Sardiñas, H., N. Williams, R. Ryals. 2023. Carbon farming can enhance pollinator resources. California Agriculture. DOI: 10.3733/ca.2022a0014
  11. Burmistrova, J., M. Beutel, E. Hestir, R. Ryals, P. Pandey. 2022. Anaerobic co-digestion to enhance waste management sustainability at Yosemite National Park. Sustainability. 14:11877. DOI: 10.3390/su141911877.
  12. Harrison, B., S. Gao, M. Gonzales, T. Thao, E. Bischak, T.A. Ghezzehei, A.A. Berhe, G. Diaz, R. Ryals. 2022. Dairy manure co-composting with wood biochar plays a critical role in meeting global methane goals. Environmental Science & Technology. DOI: 10.1021/acs.est.2c03467
  13. Heisey, S., R. Ryals, T. McClellan Maaz, N.H. Nguyen. 2022. Complex, high-nitrogen fertilizers can leave lasting impacts and alter cross-domain interaction networks. Frontiers in Soil Science. 2. DOI: 10.3389/fsoil.2022.749212
  14. Ryals, R., E. Bischak, K. Porterfield, S. Heisey, J. Jeliavoski, S. Kramer, S. Pierre. 2021. Towards zero hunger through coupled ecological sanitation-agriculture systems. Frontiers in Sustainable Food Systems. DOI: 10.3389/fsufs.2021.716140 
  15. Villa, Y., R. Ryals. 2021. Soil carbon response to long-term biosolids application. Journal of Environmental Quality. DOI: 10.1002/jeq2.20270
  16. Villa, Y., S.D. Khlasa, R. Ryals, R. Duncan, P.H. Brown, S.C. Hart. 2021. Organic matter amendments improve soil fertility in almond orchards of contrasting soil texture. Nutrient Cycling in Agroecosystems. DOI: 10.1007/s10705-021-10154-5.
  17. Cusack, D.F., C.E. Kazanski, A. Hedgpeth, K. Chow, A.L. Cordeiro, J. Karpman, R. Ryals. 2021. Reducing climate impacts of beef production: a synthesis of life cycle assessments across management systems and global regions. Global Change Biology. 27(9):1721-1736. DOI: 10.1111/gcb.15509
  18. McNicol, G., J. Jeliazovski, J.J. François, S. Kramer, R. Ryals. 2020. Climate change mitigation potential in sanitation via off-site composting of human waste. Nature Climate Change. 1-5. DOI: 10.1038/s41558-020-0782-4
  19. Harrison, B.P., E. Chopra, R. Ryals, J.E. Campbell. 2020. Quantifying the farmland application of compost to help meet California’s organic waste diversion law. Environmental Science & Technology. DOI: 10.1021/acs.est.9b05377.
  20. Ryals, R., G. McNicol, S. Porder, S. Kramer. 2019. Greenhouse gas fluxes from human waste management pathways in Haiti. Journal of Cleaner Production. DOI: 10.1016/j.jclepro.2019.04.079
  21. Clark, M., M. G. Hastings, R. Ryals. 2019. Soil carbon and nitrogen dynamics in two agricultural soils amended with manure-derived biochar. Journal of Environmental Quality. DOI: 10.2134/jeq2018.10.0384
  22. Harden, J., G. Hugelius, A. Anders, J. Blankinship, B. Bond-Lamberty, C. Lawrence, J. Loisel, A. Malhotra, R. Jackson, S. Ogle, C. Phillips, R. Ryals, K. Todd-Brown, R. Vargas, S. Vargas, F. Cotrufo, M. Keiluweit, K. Heckman, S. Crow, W. Silver, M. DeLonge, N. Lucas. 2018. Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter. Global Change Biology 24:e705-718. DOI: 10.1111/gcb.13896
  23. Clark, S. R. Ryals, D. Miller, C. Mullen, D. Pan, M. Zondlo, A.A. Boateng, M.G. Hastings. 2017. Effluent gas flux characterization during pyrolysis of chicken manure. ACS Sustainable Chemistry and Engineering. DOI: 10.1021/acssuschemeng.7b00815
  24. Tully, K., R. Ryals. 2017. Nutrient cycling in agroecosystems: Balancing food and environmental objectives. Agroecology and Sustainable Food Systems 41:761-798. DOI: 10.1080/21683565.2017.1336149
  25. Castner, E., A. Leach, N. Leary, J. Baron, J. Compton, J.N. Galloway, M. Hastings, J. Kimiecik, J. Lantz-Trissel, E. de la Reguera, and R. Ryals. 2017. The Nitrogen Footprint Network: A multi-institution program to limit nitrogen pollution. Sustainability: the Journal of Record 10:79-88. DOI: 10.1089/sus.2017.29098.eac
  26. Hastings, M.G., R.T. Barnes, J. Berry, J. Kimiecik, R. Ryals, J. Lantz-Trissel. 2017. Institutional nitrogen footprints: connections across campus. Sustainability: the Journal of Record 10:74-78. (Open access link)
  27. Cayuela, M.L., E. Aguila, A. Sanz-Cobena, D.C. Adams, D. Abalos, R. Ryals, W.L. Silver, L. Barton, M.A. Alfaro, V. Pappa, P. Smith, J. Garnier, G. Billen, A. Bondeau, L. Bouwman, L. Lassaletta. 2017. Nitrous oxide emission factors in Mediterranean climate cropping systems: a revision of the available literature and assessment of difference with official national estimate. Agriculture, Ecosystems & Environment 238:25-35. DOI: 10.1016/j.agee.2016.10.006
  28. Yang, W.H., R. Ryals, D. Cusack, W.L. Silver. 2017. Cross-biome assessment of gross soil nitrogen cycling in California ecosystems. Soil Biology & Biochemistry 107:144-155. (Open access link)
  29. Rowntree, J.E., R. Ryals, M.S. DeLonge, W.R. Teague, M.B. Chiavegato, P. Byck, T. Wang, S. Xu. 2016. Potential mitigation of Midwest grass-finished beef production emissions with soil carbon sequestration. 4:31-38. (Open access link)
  30. Ryals, R., V.E. Eviner, C.E. Stein, K.N. Suding, and W.L. Silver. 2016. Managing for multiple ecosystem services: are there tradeoffs between carbon sequestration, plant production, and plant diversity in grasslands receiving compost amendments? Ecosphere. 7:e01270. 10.1002/ecs2.1270. (Open access link)
  31. Ryals, R., M. Hartmann, W.J. Parton, M.S. DeLonge, and W.L. Silver. 2015. Simulating soil carbon and greenhouse gas dynamics in grasslands amended with compost. Ecological Applications. 25:531-545. DOI: 10.1890/13-2126.1
  32. Ryals, R., M. Kaiser, M.S. Torn, A.A. Berhe, and W.L. Silver. 2014. Impacts of organic matter amendments on carbon and nitrogen dynamics in rangeland soils. Soil Biology and Biochemistry. 68: 52-61. DOI: 10.1016/j.soilbio.2013.09.011
  33. DeLonge, M.S., R. Ryals, and W.L. Silver. 2013. A lifecycle model to evaluate carbon sequestration potential and greenhouse gas dynamics of managed grasslands. Ecosystems. 16: 963-979. DOI: 10.1007/s10021-013-9660-5
  34. Ryals, R. and W.L. Silver. 2013. Effects of organic matter amendments on net primary productivity and greenhouse gas emissions in annual grasslands. Ecological Applications 23:49-59. DOI: 10.1890/12-0620.1
  35. Ackerely, D.D., R. Ryals, W.K. Cornwell, S.R. Loarie, W.L. Silver, and T.E. Dawson (2012) Potential impacts of climate change on biodiversity and ecosystem services in the San Francisco Bay Area. Chapter in Bay Area Climate Change Impacts Report, California Energy Commission. Available online.
  36. Silver, W.L., R. Ryals, and V.E. Eviner (2010) Soil carbon storage in California rangelands. Rangeland Ecology and Management. DOI: 10.2111/REM-D-09-00106.1
  37. Lichter, J., S.A. Billings, S.E. Zegler, D. Gaindh, R. Ryals, A.C. Finzi, R.B. Jackson, E.A. Stemmlerm W.H. Schlesinger (2008) Soil carbon sequestration in a pine forest after 9 years of atmospheric CO2 enrichment. Global Change Biology 14:2910-2922. DOI: 10.1111/j.1365-2486.2008.01701.x
  38. Williams, E., N. Greenglass, and R. Ryals (2007) Carbon capture, pipeline and storage: a viable option for North Carolina utilities? The Nicholas Institute for Environmental Policy Solutions and The Center on Global Change at Duke University. Working Paper. March 8, 2007. Available online.