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

Abstract

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.

Soil phosphorus drawdown by perennial bioenergy cropping systems in the Midwestern US

“…P leaching losses (kg P ha −1 ), which were previously reported by Hussain et al (2021), were calculated by multiplying the total dissolved P concentration (mg L −1 ) in the soil leachates by daily drainage (percolation) rates (m 3 ha −1 ) estimated with the Systems Approach for Land Use Sustainability (SALUS) crop growth model (Basso & Ritchie, 2015). The SALUS water balance sub-model simulates daily surface runoff, saturated and unsaturated water flow, drainage, root water uptake, and evapotranspiration during growing and non-growing seasons and has been well calibrated for KBS soil and climatic conditions.…”

“…The SALUS water balance sub-model simulates daily surface runoff, saturated and unsaturated water flow, drainage, root water uptake, and evapotranspiration during growing and non-growing seasons and has been well calibrated for KBS soil and climatic conditions. The SALUS model was originally developed at KBS and has been used in studies of evapotranspiration (Hamilton, 2015;Hamilton et al, 2018;Hussain et al, 2019) and nutrient leaching (Hussain et al, 2019(Hussain et al, , 2020(Hussain et al, , 2021 from KBS soils. SALUS predictions of growingseason evapotranspiration-and hence percolation as the balance between precipitation and evapotranspirationare consistent with independent measurement based on eddy covariance (Abraha et al, 2015).…”

Restoring Soil Functions and Agroecosystem Services Through Phytotechnologies

“…Perennial plants that have a higher root-to-shoot ratio (24), higher root biomass production (84-86), and higher rootassociated C input through exudation and turnover (87,88) can improve soil properties that are closely linked to soil fertility, such as soil aggregation, water-holding capacity, and microbial biomass and diversity. In addition, perennial plants are known to make better use of nitrogen, as their deeper and more extensive root systems optimize inorganic N and P retention in the soil, thus reducing leaching of these elements (81,(89)(90)(91)(92). In addition, some species contribute to N retention by translocating N in their belowground biomass, such as in rhizomes at the end of the growing season (24).…”

Effect of alfalfa on subsurface (tile) nitrogen and phosphorus loss in Ohio, USA

“…(1997) found that nitrate‐nitrogen (NO 3 − –N) loads in subsurface drainage from continuous corn and corn–soybean systems were 37 and 35 times greater, respectively, than from perennial crops. In contrast, few studies have examined the effects of perennial crops on subsurface P loss, and the results have been inconsistent and dependent on crop type and management (Brye et al., 2002; Daigh et al., 2015; Hussain, 2021; T. Q. Zhang et al., 2015). For example, Daigh et al.…”