Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: November 1, 2004
Publication Date: November 1, 2004
Citation: Torbert III, H.A., King, K.W., Harmel, R.D. 2004. Potential of some soil amendments on reducing soluble p losses from manure. [abstract] American Society of Agronomy Meetings. 2004 CDROM Technical Abstract: To study the potential benefit of chemical amendments to prevent nutrient losses following manure application, a greenhouse study was conducted to examine the interaction between one of three soil amendments (lime, gypsum, and iron sulfate) and manure application as it relates to nutrient transformations and transport from water flow. Run-over boxes (2.2 m2 surface area) were constructed and fitted with water dispersion devices which provided water runoff rate equivalent to 124 mm/hr. The boxes were prepared with Bermuda grass sod and four rates of manure (0, 4.5, 9, and 13.5 Mg/ha) and amendment rates corresponding to the stochiometric requirement to precipitate P at the highest manure application rate (280 kg/ha gypsum, 206 kg/ha lime, 400 kg/ha FeSO4). Run-over events lasting for 30 min were conducted and water samples, collected at 10 min intervals, were analyzed for DRP, NH4, NO3, and heavy metals. Results indicate that the addition of iron sulfate was very effective at reducing the level of soluble P in runoff water. Unlike the lime and gypsum additions, with the addition of iron sulfate, no significant differences were noted for soluble P concentrations between the boxes receiving 13.5 Mg/ha manure and those with no manure application. The results from this study indicate that the addition of iron sulfate at the time of manure application may greatly reduce P losses in runoff from sod.