Supply and Transport Limitations on Phosphorus Losses from Agricultural Fields in the Lower Great Lakes Region, Canada
| Autor: | Christopher J. Van Esbroeck, Genevieve Ali, Ivan P. O'Halloran, Richard R. Brunke, Kevin McKague, Merrin L. Macrae, Janina M. Plach, Gilian Opolko, Gabrielle Ferguson, Tatianna M. Lozier, W. Vito Lam, M. C. English |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Canada
Biogeochemical cycle Environmental Engineering Soil texture 010501 environmental sciences Management Monitoring Policy and Law engineering.material 01 natural sciences Soil Water Movements Dominance (ecology) Waste Management and Disposal 0105 earth and related environmental sciences Water Science and Technology Hydrology Agriculture Phosphorus 04 agricultural and veterinary sciences Pollution Loam Tile drainage Soil water 040103 agronomy & agriculture engineering 0401 agriculture forestry and fisheries Environmental science Fertilizer Great Lakes Region Surface runoff |
| Zdroj: | Journal of Environmental Quality. 47:96-105 |
| ISSN: | 0047-2425 |
| Popis: | Phosphorus (P) mobilization in agricultural landscapes is regulated by both hydrologic (transport) and biogeochemical (supply) processes interacting within soils; however, the dominance of these controls can vary spatially and temporally. In this study, we analyzed a 5-yr dataset of stormflow events across nine agricultural fields in the lower Great Lakes region of Ontario, Canada, to determine if edge-of-field surface runoff and tile drainage losses (total and dissolved reactive P) were limited by transport mechanisms or P supply. Field sites ranged from clay loam, silt loam, to sandy loam textures. Findings indicate that biogeochemical processes (P supply) were more important for tile drain P loading patterns (i.e., variable flow-weighted mean concentrations ([]) across a range of flow regimes) relative to surface runoff, which trended toward a more chemostatic or transport-limited response. At two sites with the same soil texture, higher tile [] and greater transport limitations were apparent at the site with higher soil available P (STP); however, STP did not significantly correlate with tile [] or P loading patterns across the nine sites. This may reflect that the fields were all within a narrow STP range and were not elevated in STP concentrations (Olsen-P, ≤25 mg kg). For the study sites where STP was maintained at reasonable concentrations, hydrology was less of a driving factor for tile P loadings, and thus management strategies that limit P supply may be an effective way to reduce P losses from fields (e.g., timing of fertilizer application). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text