title: Modeling sustainable reuse of nitrogen-laden wastewater by poplar.
abstract: Numerical modeling was used to simulate the leaching of nitrogen (N) to groundwater as a consequence of irrigating food processing wastewater onto grass and poplar under various management scenarios. Under current management practices for a large food processor, a simulated annual N loading of 540 kg ha(-1) yielded 93 kg ha(-1) of N leaching for grass and no N leaching for poplar during the growing season. Increasing the annual growing season N loading to approximately 1,550 kg ha(-1) for poplar only, using "weekly", "daily" and "calculated" irrigation scenarios, yielded N leaching of 17 kg ha(-1), 6 kg ha(-1), and 4 kg ha(-1), respectively. Constraining the simulated irrigation schedule by the current onsite wastewater storage capacity of approximately 757 megaliters (Ml) yielded N leaching of 146 kg ha(-1) yr(-1) while storage capacity scenarios of 3,024 and 4,536 Ml yielded N leaching of 65 and 13 kg ha(-1) yr(-1), respectively, for a loading of 1,550 kg ha(-1) yr(-1). Further constraining the model by the current wastewater storage volume and the available land area (approximately 1,000 hectares) required a "diverse" irrigation schedule that was predicted to leach a weighted average of 13 kg-N ha(-1) yr(-1) when dosed with 1,063 kg-N ha(-1) yr(-1).
authors.affiliation: a University of Iowa , Department of Civil and Environmental Engineering , Seamans Center, Iowa City , IA.
authors.forename: Yusong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: a University of Iowa , Department of Civil and Environmental Engineering , Seamans Center, Iowa City , IA.
authors.forename: Louis
authors.initials: L
authors.lastname: Licht
authors.affiliation: a University of Iowa , Department of Civil and Environmental Engineering , Seamans Center, Iowa City , IA.
authors.forename: Craig
authors.initials: C
authors.lastname: Just
mesh_terms: D001673:Biodegradation, Environmental; D005308:Fertilizers; D007700:Kinetics; D008962:Models, Theoretical; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism*; D032107:Populus / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D012621:Seasons; D062065:Wastewater / Q000737:chemistry*
chemical_list: D005308:Fertilizers; D009584:Nitrogen; D062065:Wastewater
keywords: HYDRUS 1D; nitrogen management; poplar; sustainable water reuse