title: Can urban P conservation help to prevent the brown devolution?
abstract: Achieving better understanding phosphorus (P) flows through urban ecosystems is needed to conserve P, as non-renewable phosphate rock deposits become depleted and the global human population increases. A baseline mass flow analysis (MFA) for P developed for the Twin Cities Watershed (TCW, which includes most of the Minneapolis-St. Paul metropolitan region) showed that most P input was stored in the system (65%) or leaked from it (31%); only 4% was deliberately exported as useful products. In a realistic, comprehensive conservation scenario P input was reduced by 15%; deliberate export of P in the form of sewage sludge, food waste, and landscape waste was 68% of P input. In this scenario, increased deliberate export was accomplished by decreasing leakage (to 9% of input) and storage (to 23% of input). If used as agricultural fertilizer, the deliberately exported P in the conservation scenario would support about half of the food production required by the TCW.
authors.affiliation: Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, United States. baker127@umn.edu
authors.forename: Lawrence A
authors.initials: LA
authors.lastname: Baker
mesh_terms: D002947:Cities; D003247:Conservation of Natural Resources / Q000379:methods*; D055669:Ecological and Environmental Phenomena; D004777:Environment; D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000706:statistics & numerical data; D010758:Phosphorus / Q000032:analysis*
chemical_list: D010758:Phosphorus