The residential landscape: fluxes of elements and the role of household decisions

We assessed biogeochemical cycling of elements through residential household landscapes to evaluate the importance of annual to decadal household-level decisions for element fluxes that contribute to urban and regional pollution. We combined a mailed survey, vegetation measurements, and allometric and biogeochemical models to estimate fluxes and accumulation of carbon (C), nitrogen (N), and phosphorus (P) in landscapes of 360 single-family homes in the Minneapolis-Saint Paul, Minnesota metropolitan area. Carbon inputs and accumulation were strongly influenced by the presence of trees on the property. Nitrogen inputs to the landscape exceeded estimated ecosystem demand for N on average by 51% and were dominated by N fertilizer application. Because Minnesota state law restricts the use of P fertilizer, pet waste was responsible for 84% of P inputs to the landscape. The results have implications for understanding sources of urban pollution and the potential flexibility (i.e., the potential for change) in household behaviors such as tree planting, fertilization, and pet waste management that contribute to such pollution.