341-5 Correspondence of the Phosphorus Saturation Ratio Threshold with Environmental Indicators of Phosphorus Loss Risk.

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Symposium--a Critical Assessment of Phosphorus Reduction Goals and Mitigation Strategies (SERA 17)

Wednesday, November 18, 2015: 9:00 AM
Minneapolis Convention Center, 101 FG

Vimala D. Nair1, Biswanath Dari2, Debolina Chakraborty3 and Willie Harris1, (1)Soil and Water Sciences Dept., University of Florida, Gainesville, FL
(2)#1, University of Florida, Quincy, FL
(3)University of Florida, Gainesville, FL
Abstract:
The controlling influence of aluminum and iron oxides on phosphorus sorption in acid soils is manifested in several environmental indicators of phosphorus loss risk.  These include the phosphorus saturation ratio (PSR), equilibrium phosphorus concentration (EPC0), water soluble P (WSP), and P adsorption model constants (Langmuir and Freundlich). The thresholds of PSR and EPC0 correspond; in effect, EPC0 begins to precipitously increase when the PSR threshold is exceeded.  Biochar and other soil amendments including the detrital material (organic matter) in wetlands have no impact on P retention below the threshold PSR.

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Symposium--a Critical Assessment of Phosphorus Reduction Goals and Mitigation Strategies (SERA 17)