NUTRIENT AND β_(17)-ESTRADIOL LOSS IN RUNOFF WATER FROM POULTRY LITTERS

摘要

A main water quality concern is accelerated eutrophi-cation of fresh waters from nonpoint source pollution, particularly nutrient transport in surface runoff from agricultural areas and confined animal feeding operations. This study examined nutrient and β_(17)-estradiol concentrations in runoff from small plots where six poultry litters were applied at a rate of about 67 kg/ha of total phosphorus (TP). The six poultry litter treatments included pelleted compost, pelleted litter, raw litter, alum (treated) litter, pelleted alum litter, and normal litter (no alum). Four replicates of the six poultry litter treatments and a control (plots without poultry litter application) were used in this study. Rainfall simulations at intensity of 50 mm/hr were conducted immediately following poultry litter application to the plots and again 30 days later. Composite runoff samples were analyzed for soluble reactive phosphorus (SRP), ammonia (NH_4), nitrate (NO_3), TP, total nitrogen (TN) and β_(17)-estradiol concentrations. In general, poultry litter applications increased nutrient and β_(17)-estradiol concentrations in runoff water. Ammonia and P concentrations in runoff water from the first simulation were correlated to application rates of water extractable NH_4 (R~2 = 0.70) and P (R~2 = 0.68) in the manure. Results suggest that alum applications to poultry litter in houses inbetween flocks is an effective best management practice for reducing phosphorus (P) and β_(17)-estradiol concentrations in runoff and that pelleted poultry litters may increase the potential for P and β_(17)-estradiol loss in runoff water. Inferences regarding pelleted poultry litters should be viewed cautiously, because the environmental consequence of pelleting poultry litters needs additional investigation.