Modeling the Impacts of Manure on Phosphorus Loss in Surface Runoff and Subsurface Drainage

Abstract

Simulation of phosphorus (P) transfer from manured agricultural lands to water bodies via surface runoff and subsurface drainage is potentially of great help in evaluating the risks and effects of eutrophication under a range of best management practice scenarios. However, it remains a challenge since few models are capable of providing a reasonably accurate prediction of P losses under manure treatment. The Environmental Policy Integrated Climate (EPIC) model was applied to simulate the impacts on dissolved reactive P (DRP) losses through surface runoff and subsurface drainage from a solid cattle manure–amended corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation on a clay loam soil (Vertisol) located in the Lake Erie region. Simulations of DRP loss in surface runoff and tile drainage were satisfactory; however, EPIC did not consider DRP loss directly from manure, weakening its accuracy in the prediction of DRP loss in surface runoff. Having previously drawn on EPIC‐predicted surface runoff to initiate SurPhos (Surface Phosphorus and Runoff Model) predictions of DRP losses strictly in surface runoff, no comparison had been made of differences in manure application impacts on EPIC‐ or SurPhos‐predicted DRP losses—accordingly, this was assessed. The SurPhos improved the estimation of DRP loss in surface runoff (Nash–Sutcliffe coefficient, 0.53), especially when large rain events occurred immediately after or within 6 wk of manure application. Generally, EPIC can capture the impacts of manure application on DRP loss in surface runoff and subsurface drainage; however, coupling of the EPIC and SurPhos models increased the accuracy of simulation of runoff DRP losses. Core Ideas Simulations of DRP loss in surface runoff and tile drainage using EPIC were satisfactory. Simulations of DRP loss in surface runoff between EPIC and SurPhos were compared. Coupling SurPhos and EPIC improved surface DRP loss prediction with manure addition.

A review of the current state of process-based and data-driven modelling: guidelines for Lake Erie managers and watershed modellers

“…The spatial granularity should also shift from lumped approaches in BMP analysis, such as HRU in SWAT, towards field-level analysis of geographically fixed BMPs in order predict the post-implementation trends in tributary water quality. Some of the critical processes for modelling nutrient losses in individual watersheds in the Great Lakes can include simulation of runoff in sub-field areas (e.g., MIKE-SHE, SWAT-VSA in Easton et al, 2008), tracking nutrient losses at EOF and EOS nodes (APEX, AnnAGNPS, SWAT+), representing field-and farm-level structural BMPs as spatial objects (APEX, AnnAGNPS, MIKE-SHE, SWAT+, field-scale SWAT in Merriman et al, 2018), improved representation of groundwater and surface-water interactions in tile-drained landscapes with high water tables (HYPE, MIKE-SHE, SWAT+) and related simulation of tile-drainage nutrient losses (e.g., SWATDRAIN modification in Golmohammadi et al, 2016), consideration of spatiotemporally explicit soil erosion routines (SWAT modification by Qi et al, 2017; AnnAGNPS, MIKE-SHE), augmentation of reactive nutrient transport dynamics in agricultural land, such as the modified SWAT in Collick et al (2016) or the modified EPIC in Wang et al (2019).…”

Modeling of phosphorus loss from field to watershed: A review

“…After including labile P in PSC calculation (Equation 8, Table 2), Vadas and White (2010) presented increased accuracy in simulation of soil P dynamics, especially for several weeks after P addition. Thus, the updated P sorption–desorption processes were coded into the SurPhos (Surface Phosphorus and Runoff Model) and APLE (Annual P Loss Estimator) models, which have been applied to confirm and show their enhanced accuracy in simulating P levels (Collick et al., 2016; Fiorellino, McGrath, Vadas, Bolster, & Coale, 2017; Mulkey, Coale, Vadas, Shenk, & Bhatt, 2017; Wang, Zhang, Tan, Vadas, et al., 2018; Wang et al., 2019).…”

“…Most of the models derived from EPIC assume P added from manure to be well mixed with soil and to quickly become part of soil P pools, thereby underpredicting P losses in runoff, especially when intense precipitation events occur shortly after manure application (Wang et al., 2019). Vadas, Haggard, & Gburek (2005) and Vadas, Kleinman, and Sharpley (2004) developed a model that enables us to accurately predict P loss in runoff directly from surface‐applied unincorporated manures by adding a specific manure pool.…”

“…The RZWQM2 model features Hooghoudt's equation for steady‐state drainage, Poiseuille's law for preferential flow, Richards’ equation for soil water redistribution, the freeze–thaw process, and many field management practices. Even though a few papers (Wang, Zhang, Tan, Taylor, et al., 2018; Wang et al., 2019) have shown the capacity of EPIC to simulate P loss in tile drainage by adjusting the crack flow coefficient to mimic preferential flow, there remain some limitations to this approach due to the constant crack flow coefficient and simplified tile drainage as lateral subsurface flow. Incorporation of preferential flow into current existing models seems a feasible way to guarantee accurate prediction of P loss regardless of its complexity.…”

Assessment of Soil and Water Conservation Practices in the Loess Hilly Region Using a Coupled Rainfall-Runoff-Erosion Model

“…The use of fertilizers in the farmlands with soils prone to erosion risk may affect groundwater and surface water quality. For example, the dissolved reactive phosphorus from fertilizers will transport with surface runoff from farmlands, accelerating eutrophication in receiving water bodies [8]. The release of heavy metals such as Zn, Cr, Cd, Hg, and Pb from soil erosion may also pose a risk for human health [9].…”