Quality of Runoff from Fescuegrass Plots Treated with Poultry Litter and Inorganic Fertilizer
- D. R. Edwards * and
- T. C. Daniel
Recent application of either organic or inorganic fertilizers can promote increased runoff concentrations of nutrients, organic matter, and/or suspended sofids. This experiment assessed the impacts of fertilizer treatment (control, poultry litter, and inorganic fertilizer) and simulated rainfalls (four events, one each at 7, 14, 36, and 68 d after application) on quality of runoff from fescuegrass (Festuca arundinacea Schreber) plots. Runoff was produced by simulated rainfall (50 mm h−1) and sampled at 0.08-h intervals during runoff. Composite runoff samples from each plot were analyzed for NO3-N, NH3-N, total Kjeldahl (TKN), ortho-P (PO4-P), total P, chemical oxygen demand (COD), and total suspended solids (TSS). For the first simulated rainfall event, runoff concentrations of NO3-N, NH3-N, TKN, PO4-P, and total P were highest from the plots that received inorganic fertilizer, while the highest concentrations of COD and TSS occurred in runoff from plots treated with poultry litter. Mean concentrations of NO3-N, NH3-N, TKN, PO4-P, and total P in runoff from the litter-treated plots during the second simulated rainfall were not significantly different than observed in runoff from the control plots. Runoff quality from the plots receiving poultry litter and inorganic fertilizer did not significantly differ from background (control) levels during the third simulated rainfall (with natural runoff occurring twice between the second and third simulated rainfalls). Runoff losses of parameters investigated were generally highest for the first simulated rainfall. Losses of N and P from the treated plots summed over all four simulated rainfalls were very small proportions of amounts applied (≈1.4 and 2.7%, respectively).Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .