Monday, November 5, 2007

Surface Runoff Nutrient Losses from Claypan Soil Receiving Fertilizer and Turkey Litter.

Daniel W. Sweeney, Southeast Agricultural Research Center, Kansas State University, PO Box 316, Parsons, KS 67357 and Gary M. Pierzynski, Dept. of Agronomy, Kansas State University, 2004 Throckmorton Hall, Manhattan, KS 66506-5501.

Surface runoff losses of nutrients and sediment are significant threats to surface water quality. Little information is available on relative losses of nutrients from animal wastes as compared to commercial fertilizers, especially in southeastern Kansas. The objectives of this study were: i) to compare surface runoff losses of nutrients and sediment from fertilizer and turkey litter manure nutrient sources and ii) to determine the influence of tillage on nutrient and sediment losses in surface runoff from the use of fertilizer and turkey litter. The experiment was initiated in 2005 near Girard, KS. The soil was a Parsons silt loam overlying a claypan B horizon. The treatments were: 1) control no fertilizer or turkey litter applied, 2) fertilizer only commercial fertilizer to supply N and P with no turkey litter, 3) turkey litter (N based) turkey litter applications to supply all N [that also provides excess P], 4) turkey litter (P based) turkey litter applications to supply all P with supplemental fertilizer N, and 5) turkey litter (P based) same as treatment #4 but with incorporation of litter and fertilizer. Treatments 1 through 4 were planted with no tillage, but treatment #5 was planted after chisel and disk incorporation of the litter and fertilizer. Phosphorus losses were greater when turkey litter was applied based on crop N needs. Applying turkey litter based on crop P needs reduced P losses, especially when incorporated. Nitrogen losses appeared to be a bit more variable, but values seemed low. Incorporation by conventional tillage generally resulted in greater sediment loss, but these losses were small on this soil typical of southeastern Kansas.