Phosphorus availability and leaching losses in annual and perennial cropping systems in an upper US Midwest landscape

• Published in: Scientific reports Vol. 11; no. 1; pp. 20367 - 12
• Main Authors: Hussain, Mir Zaman, Hamilton, Stephen K., Robertson, G. Philip, Basso, Bruno
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13.10.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 704/172; 704/242; 704/47; Agricultural land; biogeochemistry; Cereal crops; Corn; Crop management; Cropping systems; ENVIRONMENTAL SCIENCES; Eutrophication; Fertilization; Groundwater; Growing season; Humanities and Social Sciences; hydrology; Lakes; Leaching; Lysimeters; Moisture content; multidisciplinary; Panicum virgatum; Phosphorus; Science; Science (multidisciplinary); Soil testing; Soil water; Streams; Surface runoff; Surface water; Water depth; United States > US
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-99877-7

Excessive phosphorus (P) applications to croplands can contribute to eutrophication of surface waters through surface runoff and subsurface (leaching) losses. We analyzed leaching losses of total dissolved P (TDP) from no-till corn, hybrid poplar ( Populus nigra X P. maximowiczii ), switchgrass ( Panicum virgatum ), miscanthus ( Miscanthus giganteus ), native grasses, and restored prairie, all planted in 2008 on former cropland in Michigan, USA. All crops except corn (13 kg P ha −1  year −1 ) were grown without P fertilization. Biomass was harvested at the end of each growing season except for poplar. Soil water at 1.2 m depth was sampled weekly to biweekly for TDP determination during March–November 2009–2016 using tension lysimeters. Soil test P (0–25 cm depth) was measured every autumn. Soil water TDP concentrations were usually below levels where eutrophication of surface waters is frequently observed (> 0.02 mg L −1 ) but often higher than in deep groundwater or nearby streams and lakes. Rates of P leaching, estimated from measured concentrations and modeled drainage, did not differ statistically among cropping systems across years; 7-year cropping system means ranged from 0.035 to 0.072 kg P ha −1  year −1 with large interannual variation. Leached P was positively related to STP, which decreased over the 7 years in all systems. These results indicate that both P-fertilized and unfertilized cropping systems may leach legacy P from past cropland management.