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Reducing Water‐Soluble Phosphorus in Soil through Flue Gas Desulfurization Gypsum Application: Year of Application Effects at Multiple Sites in Wisconsin
Author(s) -
Sindelar Meghan E.,
Wolkowski Richard P.
Publication year - 2019
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq2018.05.0217
Subject(s) - flue gas desulfurization , gypsum , phosphorus , environmental science , environmental chemistry , waste management , environmental engineering , chemistry , hydrology (agriculture) , engineering , metallurgy , geotechnical engineering , materials science , organic chemistry
Phosphorus runoff from agricultural land to surface water bodies, such as the Great Lakes, is an important environmental concern. Soil amendments, such as gypsum, may alter the chemistry of the soil solution to reduce the amount of water‐soluble P (WSP) available for loss to runoff, and as such, the NRCS now recommends gypsum application as a Conservation Practice Standard (Code 333) for improving water quality. Interest in gypsum use has also increased as availability has increased from production of flue gas desulfurization (FGD) gypsum at many coal‐burning power plants throughout the United States. This study tested three rates of unincorporated, surface‐broadcast FGD gypsum application at 23 field sites in Wisconsin. The optimal rate for reducing WSP concentration and the relationship between selected soil properties and the beneficial effect of FGD gypsum application were evaluated. The FGD gypsum reduced WSP ( P < 0.0001), with a significant effect compared with the control at the lowest tested rate of 1120 kg ha −1 at 5 of the 23 sites. Few other sites saw a significant benefit. Correlation indicated that sites showing a beneficial reduction of WSP from FGD gypsum application were those with greater soil test P ( P = 0.0002) and lower cation exchange capacity ( P = 0.0087) values. Core Ideas Not all sites benefit from flue gas desulfurization (FGD) gypsum application. FGD gypsum is useful in reducing water‐soluble P in soil and the potential for P in runoff. Sites with high soil test P and low cation exchange capacity benefit more from FGD gypsum.