Legacies of Nutrient Accumulation and Depletion in Residential Ecosystems

Abstract

In residential ecosystems, land management can help regulate climate and improve water quality by promoting the accumulation of nutrients in the soil. We tested how varying intensity of residential land use and management altered nutrient (Ca, K, Mg, P, S) pools. We studied soils and vegetation across twelve land use-intensity gradients (yards-perennial old fields-forests) established 15–227 y. ago in the native ecosystems of temperate forests. We found that yard soils were enriched with nutrients relative to fields and forests, regardless of recent yard management intensity. Yard soils from 0- to 40-cm depth contained an average 72–93% more Ca, 11–22% more Mg and 18–50% more P than fields and forests. In the upper 20 cm of soil, where land-use effects were pronounced, 200-year-old yards contained 24% more soil P than one decade-old yards. Yards where managers exported grass clippings for forty years contained less soil K and Mg than yards managed similarly for ten years. Yard soil cation exchange capacity and C were not correlated, suggesting the importance of inorganic mechanisms of nutrient accumulation. With more intense land use, across yards-fields-forests and within yards, soil S and C tightly covaried indicating these nutrients may limit or stimulate organic nutrient cycling. Our research suggests residential land management can contribute to nutrient legacies that support resilient responses to global change.