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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. In Press 2019. Denitrifying bioreactor inflow manifold design influences treatment of aquacultural wastewater. Aquacultural Engineering.
  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 in press.


Non-Peer Reviewed Outreach Publications Available Online

  1. Christianson, L., and M. Helmers. 2011. Woodchip bioreactors for nitrate in agricultural drainage. Iowa State University Extension Publication PMR 1008 (double blind expert-reviewed). Available at:
  2. Christianson, L. 2016. Nutrient loss reduction: Using science to find the right practices for your field. Illinois Extension and Illinois Water Resources Center (4-pg factsheet). Available at:
  3. Christianson, L., J. Frankenberger, C. Hay, M. Helmers, and G. Sands (Eds.). 2016. Ten ways to reduce nitrogen loads from drained cropland in the Midwest. Urbana, IL: Illinois Extension. (Open peer review). Available at:
  4. Hertzberger, A. and L. Christianson. 2018. Concentrating on nutrient loss: A review of tile drainage nutrient concentrations. University of Illinois Extension, Urbana, Illinois (2-pg factsheet).
  5. Christianson, L., J. Frankenberger, C. Hay, M. Helmers, and G. Sands. 2018. Ten ways to reduce nitrogen loads from drained cropland in the Midwest: A summary factsheet. University of Illinois Extension, Urbana, Illinois (4-pg factsheet).
  6. Christianson, L., K. Addy, A. Gold, and L. Schipper. 2018 Woodchip Bioreactors: A science-based option to reduce nitrate loss. University of Illinois Extension, Urbana, Illinois (2-pg factsheet).
  7. Woodyard, J., L. Christianson, C. Penn, M. Kalcic, K. W. King, M. R. Williams, M. L. Macrae, Fausey, J. Frankenberger, D. R. Smith, P. J. A. Kleinman, and L. C. Brown. 2020. Solutions to minimize phosphorus loss through subsurface tile drains. University of Illinois Extension factsheet CSWQ-0120. Available at: