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Peer-Reviewed Publications

  1.  Christianson, L., A. Castelló, R. Christianson, A. Bhandari, and M. Helmers. 2010. Technical note: Hydraulic property determination of denitrifying bioreactor fill media. Applied Engineering in Agriculture 26(5): 849‐854.
  2.  Christianson, L., A. Bhandari, and M. Helmers. 2011. Pilot-scale evaluation of denitrification drainage bioreactors: Reactor geometry and performance. Journal of Environmental Engineering 137(4): 213-220.
  3. Christianson, L., J. Hanly, and M. Hedley. 2011. Optimized denitrification bioreactor treatment through simulated drainage containment. Agricultural Water Management 99(1):85-92.
  4. Christianson, L., and J. Tyndall. 2011. Seeking a dialog: A targeted technology for sustainable agricultural systems in the American Corn Belt. Sustainability: Science, Practice, & Policy 7(2). Available at:
  5. Christianson, L., A. Bhandari, M. Helmers, K. Kult, T. Sutphin, and R. Wolf. 2012. Performance evaluation of four field-scale agricultural drainage denitrification bioreactors in Iowa. Transactions of the ASABE 55(6): 2163-2174.
  6. Christianson, L., A. Bhandari, and M. Helmers. 2012. A practice-oriented review of woodchip bioreactors for subsurface agricultural drainage. Applied Engineering in Agriculture 28(6): 861-874.
  7. Christianson, L., N. Hoover, A. Bhandari, and M. J. Helmers. 2012. Technical Note: The potential of municipal yard waste to be denitrification bioreactor fill. Applied Engineering in Agriculture 28(6): 853-859.
  8. Christianson, L., R. Christianson, M. Helmers, C. Pederson, and A. Bhandari. 2013. Modeling and calibration of drainage denitrification bioreactor design criteria. Irrigation and Drainage Engineering 139(9): 699-709.
  9. Christianson, L. M. Helmers, A. Bhandari, and T. Moorman. 2013. Internal hydraulics of an agricultural drainage denitrification bioreactor. Ecological Engineering 52: 298-307.
  10. Christianson, L., M. Smith, D. Storm, M. White, S. Stoodley. 2013. Evaluating Remote Sensing Methods for Targeting Erosion in Riparian Corridors. Proceedings of the Oklahoma Academy of Science, 93: 55-65.
  11. Christianson, L., J. Tyndall, and M. Helmers. 2013. Financial comparison of seven nitrate reduction strategies for Midwestern agricultural drainage. Water Resources and Economics 2-3:30-56.
  12. Christianson, L., T. Knoot, D. Larsen, J. Tyndall, and M. Helmers. 2014. Adoption potential of nitrate mitigation practices: an ecosystem services approach. International Journal of Agricultural Sustainability 12(4): 407-424.
  13. Christianson, L., and S. Summerfelt. 2014. Fluidization velocity assessment of commercially available sulfur particles for use in autotrophic denitrification biofilters. Aquacultural Engineering 60:1-5.
  14. Christianson, L., and R. Harmel. 2015. The MANAGE Drain Load database: Review and compilation of more than fifty years of North American drainage nutrient studies. Water Management 159:277-289.
  15. Feyereisen, G., and L. Christianson. 2015. Hydraulic flow characteristics of agricultural residues for denitrifying bioreactor media. Applied Engineering in Agriculture 31(1): 89-96.
  16. Tsukuda, S., L. Christianson, K. Saito, A. Kolb, and S. Summerfelt. 2015. Heterotrophic denitrification of aquaculture effluent using fluidized sand biofilters. Aquacultural Engineering 64:49-59.
  17.  Christianson, L., and R. Harmel. 2015. 4R water quality impacts: An assessment and synthesis of forty years of drainage nitrogen losses. Journal of Environmental Quality 44(6):1852-1860.
  18.  Christianson, L., C. Lepine, S. Tsukuda, K. Saito, and S. Summerfelt. 2015. Nitrate removal effectiveness of fluidized sulfur-based autotrophic denitrification biofilters for recirculating aquaculture systems. Aquacultural Engineering 68:10-18.
  19. Christianson, L. and L. Schipper. 2016. Moving denitrifying bioreactors beyond proof of concept: Introduction to the special section. Journal of Environmental Quality 45(3): 757-761.
  20. Addy, K., A. Gold, L. Christianson, M. David, L. Schipper, and N. Sacha. 2016. Denitrifying Bioreactors for Nitrate Removal: A Meta-analysis. Journal of Environmental Quality 45(3): 873-881.
  21. Feyereisen, G., T. Moorman, L. Christianson, R. Venterea, J. Coulter, U. Tschirner. 2016. Performance of agricultural residue media in laboratory denitrifying bioreactors at low temperatures. Journal of Environmental Quality 45(3): 779-787.
  22. Sharrer, K., L. Christianson, C. Lepine, and S. Summerfelt. 2016. Modeling and mitigation of denitrification ‘woodchip’ bioreactor phosphorus releases during treatment of aquaculture wastewater. Ecological Engineering 93:135-143.
  23. Lepine, C., L. Christianson, K. Sharrer, and S. Summerfelt. 2016. Optimizing hydraulic retention times in denitrifying woodchip bioreactors treating recirculating aquaculture system wastewater. Journal of Environmental Quality 45(3): 813-821.
  24. Christianson, L., C. Lepine, K. Sharrer, and S. Summerfelt. 2016. Denitrifying bioreactor clogging potential during wastewater treatment. Water Research 105:147-156.
  25. Harmel, R., L. Christianson, M. McBroom, D. Smith, and K. Higgs. 2016. Expansion of the MANAGE database with forest and drainage studies. Am. Water Res. Assoc’n. 10.1111/1752-1688.12438.
  26. Christianson, L., R. Harmel, D. Smith, M. Williams, and K. King. 2016. Assessment and synthesis of 50 years of published drainage phosphorus losses. Journal of Environmental Quality 45(5):1467-1477.
  27. Zhao, X., L. Christianson, D. Harmel, and C. Pittelkow. 2016. Assessment of drainage nitrogen losses on a yield-scaled basis. Field Crops Research 199:156-166.
  28. Rosen, T. and L. Christianson. 2017. Performance of denitrifying bioreactors at reducing agricultural nitrogen pollution in a humid subtropical coastal plain environment. Water 9(2):112.
  29. Christianson, L., D. DeVallance, J. Faulkner, and T. Basden. 2017. Scientifically advanced woody media for improved water quality from livestock woodchip heavy-use areas. Frontiers of Environmental Science and Engineering 11:2 doi:10.1007/s11783-017-0909-7.
  30. Feyereisen, G., L. Christianson, T. Moorman, R. Venterea, and J. Coulter. 2017. Plastic biofilm carrier after corn cobs reduces nitrate loading in laboratory denitrifying bioreactors. Journal of Environmental Quality 46:915-920 doi: 10.2134/jeq2017.02.0060.
  31. Christianson, L., C. Lepine, P. Sibrell, C. Penn, and S. Summerfelt. 2017. Denitrifying woodchip bioreactor and phosphorus filter pairing to minimize pollution swapping. Water Research 121:129-139
  32. Eagle, A., R. Cook, L. Christianson, D. Harmel, F. Miguez, S. Qian, D. Diaz. 2017. Meta-analysis constrained by data: Recommendations to improve relevance of nutrient management research. Agronomy Journal 109(6):2441-2449. doi: 10.2134/agronj2017.04.0215.
  33. Christianson, L., A. Collick, R. Bryant, T. Rosen, E. Bock, A. Allen, P. Kleinman, E. May, and Z. Easton. 2017. Enhanced denitrification bioreactors hold promise for Mid-Atlantic ditch drainage. Agricultural & Envir. Letters 2:170032. doi: 10.2134/ael2017.09.0032.
  34. Christianson, R., L. Christianson, C. Wong, M. Helmers, G. McIsaac, D. Mulla, and M. McDonald. 2018. Beyond the nutrient strategies: Common ground to accelerate water quality improvement in the Upper Midwest. Journal of Environmental Management 206:1072-1080.
  35. Li, S., R. Cooke, X. Huang, L. Christianson, and R. Bhattarai. 2018. Evaluation of fly ash pellets for phosphorus removal in a laboratory scale denitrifying bioreactor. Journal of Environmental Management 207:269-275.
  36. Lepine, C., L. Christianson, J. Davidson, and S. Summerfelt. 2018. Woodchip bioreactors as treatment for recirculating aquaculture systems’ wastewater: A cost assessment of nitrogen removal. Aquacultural Engineering 83:85-92
  37. Christianson, L., G. Feyereisen, C. Lepine, and S. Summerfelt. 2018. Plastic carrier polishing chamber reduces pollution swapping from denitrifying woodchip bioreactors. Aquacultural Engineering 81:33-37.
  38. Maxwell, B., F. Birgand, L. Schipper, L. Christianson, S. Tian, M. Helmers, D. Williams, G. Chescheir, and M. Youssef. 2019. Impact of drying-rewetting cycles on nitrate removal rates in woodchip bioreactors. Journal of Environmental Quality 48(1):93-101.
  39. Chandrasoma, J.M., R.D. Christianson, and L.E. Christianson. 2019. Saturated buffers: What is their potential impact across the US Midwest? Agricultural & Environmental Letters 4: 180059. doi: 10.2134/ael2018.11.0059.
  40. Preza Fontes, G., R. Bhattarai, L. Christianson, and C. Pittelkow. 2019. Combining environmental monitoring and remote sensing technologies to evaluate cropping system nitrogen dynamics at the field-scale. Frontiers in Sustainable Food Systems 3(8) doi: 10.3389/fsufs.2019.00008.
  41. Hertzberger, A., C.M. Pittelkow, R.D. Harmel, and L.E. Christianson. 2019. The MANAGE Drain Concentration database: A new tool compiling North American drainage nutrient concentrations. Agricultural Water Management 216:113-117.
  42. Ezzati, G., M.G. Healy, L.E. Christianson, G.W. Feyereisen, S. Thornton, K. Daly, and O. Fenton. 2019. Developing and validating a decision support tool for media selection to mitigate drainage waters. Ecological Engineering X: 2.
  43. Maxwell, B., F. Birgand, L. Schipper, L. Christianson, S. Tian, M. Helmers, D. Williams, G. Chescheir, and M. Youssef. 2019. Increased duration of drying-rewetting cycles increases nitrate removal in woodchip bioreactors. Agricultural & Environmental Letters. doi:10.2134/ael2019.07.0028.
  44. Christianson, L.E., R.D. Christianson, A.E. Lipka, S. Bailey, J. Chandrasoma*, C. McCoy*, G. Preza Fontes*, J. Roh*, A.P. Sanchez Bustamante Bailon*, N. Wickramarathne*, and R.A. Cooke. 2019. Calibration of stainless steel-fronted v-notch weir stop logs for water level control structures. Applied Engineering in Agriculture 35(5): 745-749.
  45. Hertzberger, A.J., C.M. Pittelkow, R.D. Harmel, and L.E. Christianson. 2019. Analysis of the MANAGE Drain Concentration database to evaluate agricultural management effects on drainage water nutrient concentrations. Transactions of the ASABE 62(4):929-939.
  46. Lepine, C., L. Christianson, G. McIssac, and S. Summerfelt. 2020. Denitrifying bioreactor inflow manifold design influences treatment of aquacultural wastewater. Aquacultural Engineering 88:102036.
  47. Daly, K., G. Ezzati, O. Fenton, M.G. Healy, L. Christianson, G. Feyereisen, S. Thornton, Q. Chen, B. Fan, and J. Ding. 2020. Impact of P inputs on source-sink P dynamics of sediment along an agricultural ditch network. Journal of Environmental Management 257:109988. doi: 10.1016/j.jenvman.2019.109988.
  48. Li, S., R. Bhattarai, R. Cooke, S. Verma, X. Huang, M. Markus, and L. Christianson. 2020. Relative performance of different data mining techniques for nitrate concentration and load estimation in different type of watersheds. Environmental Pollution 263A: 114618.
  49. Christianson, L.E., G.W. Feyereisen, C.H. Hay, U.W. Tschirner, K. Kult, N. Wickramarathne, N.L. Hoover, and M.L. Soupir. 2020. Denitrifying bioreactor woodchip recharge: Media properties after 9 years. Transactions of the ASABE 63(2): 407-416.
  50. Dougherty, H., R.A.C. Cooke, R. Bhattarai, and L. Christianson. 2020. Design flow evaluation of a wide denitrifying bioreactor with baffles. Ecological Engineering 158:106068.
  51. Wickramarathne, N., R.A. Cooke, R. Book, and L.E. Christianson. 2020. Denitrifying woodchip bioreactor leachate tannic acid and true color: Lab and field studies. Transactions of the ASABE 63(6): 1747-1757. doi: 10.13031/trans.14020.
  52. Maxwell, B.M., F. Birgand, L.A. Schipper, G. Barkle, A.A. Rivas, M.J. Helmers, and L.E. Christianson. 2020. High-frequency, in situ sampling of field woodchip bioreactors reveals sources of sampling bias and hydraulic inefficiencies. Journal of Environmental Management 272:110996. doi: 10.1016/j.jenvman.2020.110996.
  53. Preza-Fontes, G., E.D. Nafziger, L.E. Christianson, and C.M. Pittelkow. 2020. Relationship of in-season soil nitrogen concentration with corn yield and potential nitrogen losses. Soil Science Society of America Journal 84: 1296-1306.
  54. Ezzati, G., M. Healy, L. Christianson, K. Daly, O. Fenton, G. Feyereisen, S. Thornton, and O. Callery. 2020. Use of rapid small-scale column tests for simultaneous prediction of phosphorus and nitrogen retention in large-scale filters. Journal of Water Process Engineering 37:101473. org/10.1016/j.jwpe.2020.101473.
  55. Wickramarathne, N.M., L.E. Christianson,E. Foltz, J.L. Zilles, R.D. Christianson, and R.A. Cooke. 2021. Biological nitrate removal with Emerald Ash Borer-killed ash and high-tannin oak woodchips. Frontiers in Environmental Science 9(73): 648393. doi: 10.3389/fenvs.2021.648393.
  56.  Lepine, C., L. Christianson, D. Soucek, G. McIsaac, and S. Summerfelt. 2021. Metal leaching and ecotoxicity of denitrifying woodchip bioreactor outflow- potential reuse of effluent water. Aquacultural Engineering 93: 102129.
  57. Christianson, L.E., R.A. Cooke, C.H. Hay, M.J. Helmers, G.W. Feyereisen, A.Z. Ranaivoson, J.T. McMaine, R. McDaniel, T.R. Rosen, W.T. Pluer, L.A. Schipper, H. Dougherty, R.J. Robinson, I.A. Layden, S.M. Irvine-Brown, F. Manca, K. Dhaese, V. Nelissen, and M. von Ahnen. 2021. Effectiveness of denitrifying bioreactors on water pollutant reduction from agricultural areas. Transactions of the ASABE 64(2):641-658. doi: 10.13031/trans.14011.
  58. Chengjin, M., L. Christianson, X. Huang, R. Christianson, R.A. Cooke, R. Bhattarai, and S. Li. 2021. Efficacy of heated tourmaline in reducing biomass clogging within woodchip bioreactors. Science of the Total Environment 755:142401.
  59. Jeyakumar, L., D. McKenzie, L. Christianson, and E. Derdall. Accepted April 2021. Initial validation of a replicated full-size denitrifying bioreactor facility in a boreal environment. Advances in Environmental and Engineering Research.