title: Evaluating causes of trends in long-term dissolved reactive phosphorus loads to Lake Erie.
abstract: Renewed harmful algal blooms and hypoxia in Lake Erie have drawn significant attention to phosphorus loads, particularly increased dissolved reactive phosphorus (DRP) from highly agricultural watersheds. We use the Soil and Water Assessment Tool (SWAT) to model DRP in the agriculture-dominated Sandusky watershed for 1970-2010 to explore potential reasons for the recent increased DRP load from Lake Erie watersheds. We demonstrate that recent increased storm events, interacting with changes in fertilizer application timing and rate, as well as management practices that increase soil stratification and phosphorus accumulation at the soil surface, appear to drive the increasing DRP trend after the mid-1990s. This study is the first long-term, detailed analysis of DRP load estimation using SWAT.
authors.affiliation: School of Natural Resources & Environment, University of Michigan, Ann Arbor, Michigan 48109, United States. daloglu@umich.edu
authors.forename: Irem
authors.initials: I
authors.lastname: Daloğlu
authors.forename: Kyung Hwa
authors.initials: KH
authors.lastname: Cho
authors.forename: Donald
authors.initials: D
authors.lastname: Scavia
mesh_terms: D000383:Agriculture; D004784:Environmental Monitoring; D005308:Fertilizers; D006114:Great Lakes Region; D008962:Models, Theoretical; D009820:Ohio; D010758:Phosphorus; D014876:Water Pollution; D014887:Weather
chemical_list: D005308:Fertilizers; D010758:Phosphorus