Color and nutrient variation in stratified beef feedyard pond sludge
1998
Parker, D.B.
Samples of stratified sludge were collected from a feedyard runoff storage pond to assess variation in nutrient concentrations for land application. Sludge layers were subdivided based on visual color differences. Colors were identified visually using Munsell charts and electronically using a Minolta CR-300 electronic tristimulus color analyzer. Each sludge layer was analyzed for moisture content, organic matter, volatile solids, chloride, nitrate, ammonium, total Kjeldahl nitrogen (TKN), potassium, phosphorus, sulfate, electrical conductivity, and pH. Correlation analyses were performed to determine if sludge color was related to any of these parameters. Primary nutrient concentrations varied considerably among the layers. TKN concentrations ranged from 2200 to 10500 mg/kg dry basis (10.6 to 50.5 lbs/1000 gal). Bray phosphorus ranged from 266 to 656 mg/kg dry basis (1.3 to 3.1 lbs/1000 gal). Potassium ranged from 5322 to 7688 mg/kg dry basis (25.6 to 37.0 lbs/1000 gal). N-P-K ratios were inconsistent among layers. There was little statistical evidence that primary nutrient concentrations were correlated with sludge color (...r... = 0.09 to 0.38 for tristimulus Y values). The wide variation in primary nutrients among layers demonstrates the importance of adequate sampling before selecting land application rates. Rather than sampling based on visual sludge layering, it is recommended that a sample from the entire sludge profile be collected and analyzed prior to developing land application recommendations.
显示更多 [+] 显示较少 [-]