Grazed pastures represent a potential source of non‐point pollution. In comparison to other nonpoint sources (e.g., row‐cropped lands), relatively little information exists regarding possible magnitudes of pollution from grazed pasture; how that pollution is affected by weather, soil, management and other variables; and how the pollution can be minimized. The objective of this study was to assess how the quality of runoff from fescue plots is influenced by duration of cattle manure application (4–12 weeks) and manure application strategy (none, weekly application of 1.4 kg/plot, and monthly application at 5.6 kg/plot). Additional analyses were performed to relate runoff quality to the timing of sample collection. The study was conducted at the University of Kentucky Maine Chance Agricultural Experiment Station north of Lexington. Plots (2.4 m wide by 6.1 m long) were constructed and established in Kentucky 31 fescue (Festuca arundinacea Schreb.) to represent pasture. Grazing was simulated by application of beef cattle manure to the plots. Runoff was generated by applying simulated rainfall approximately 4, S and 12 weeks following initiation of manure application. Runoff samples were collected and analyzed according to standard methods for nitrogen (N), phosphorus (P) and fecal coliforms (FC). Runoff concentrations of N and P from manure‐treated plots were low and generally not consistently different from control plot concentrations or related to manure application strategy. Runoff FC concentrations from manure‐treated plots were higher than from control plot concentrations. Runoff concentrations of ammonia N, total Kjeldahl N, ortho‐P and FC decreased approximately exponentially in response to increasing time of sample collection. These findings suggest that manure deposition on well‐managed pasture at the rates used in this study might have a negligible impact on nutrient content of runoff.

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Ammonia (NH3) emission from a grow‐finish swine (Sus scrofa) building with an underfloor manure storage pit was evaluated during warm weather from 26 June to 25 September. Average daily mean (ADM, covering all measurement days) outdoor temperature was 21.8°C. Ammonia concentrations, ventilation rates, and temperatures were continuously measured or recorded and 88 d of reliable data were obtained. Air samples were taken at wall and pit exhaust fans and in the pit headspace. The NH3 concentrations were monitored on‐site with a chemiluminescence NH3 analyzer. Ventilation rates were calculated based on operation of five wall fans, four pit fans, and the fan static pressure. The NH3 emission rates were calculated by multiplying simultaneously measured NH3 concentrations and ventilation rates of wall and pit exhaust fans. The ADM of building NH3 concentration (mean concentration of all sampling locations) was 3.9 mg m−1. The ADM building NH, emission (sum of the emissions from all ventilation fans) was 11.2 kg d−1, equivalent to 145 g d−1 per AU (animal unit = 500 kg animal weight). The ADM emission per AU was higher than other reported values, probably due to warmer temperatures and higher ventilation rates. The building NH3 concentrations were inversely proportional to the indoor temperatures (r = −0.66) and ventilation rates (r = −0.59) and correlated well to total pig weight (r = 0.49). The building NH3 emission rates were correlated to total pig weights (r = 0.52) and ventilation rates (r = 0.41) and were not well correlated to indoor temperatures (r = 0.12).

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Federally funded, multistate field studies were initiated in 2002 to measure emissions of particulate matter (PM) Ͻ10 m (PM 10 ) and total suspended particulate (TSP), ammonia, hydrogen sulfide, carbon dioxide, methane, nonmethane hydrocarbons, and odor from swine and poultry production buildings in the United States. This paper describes the use of a continuous PM analyzer based on the tapered element oscillating microbalance (TEOM). In these studies, the TEOM was used to measure PM emissions at identical locations in paired barns. Measuring PM concentrations in swine and poultry barns, compared with measuring PM in ambient air, required more frequent maintenance of the TEOM. External screens were used to prevent rapid plugging of the insect screen in the PM 10 preseparator inlet. Minute means of mass concentrations exhibited a sinusoidal pattern that followed the variation of relative humidity, indicating that mass concentration measurements were affected by water vapor condensation onto and evaporation of moisture from the TEOM filter. Filter loading increased the humidity effect, most likely because of increased water vapor adsorption capacity of added PM. In a single layer barn study, collocated TEOMs, equipped with TSP and PM 10 inlets, corresponded well when placed near the inlets of exhaust fans in a layer barn. Initial data showed that average daily mean concentrations of TSP, PM 10 , and PM 2.5 concentrations at a layer barn were 1440 Ϯ 182 g/m 3 (n ϭ 2), 553 Ϯ 79 g/m 3 (n ϭ 4), and 33 Ϯ 75 g/m 3 (n ϭ 1), respectively. The daily mean TSP concentration (n ϭ 1) of a swine barn sprinkled with soybean oil was 67% lower than an untreated swine barn, which had a daily mean TSP concentration of 1143 Ϯ 619 g/m 3 . The daily mean ambient TSP concentration (n ϭ 1) near the swine barns was 25 Ϯ 8 g/m 3 . Concentrations of PM inside the swine barns were correlated to pig activity. INTRODUCTIONAlthough several studies of total suspended particulate (TSP) concentrations have been conducted, data concerning emissions of TSP and particulate matter (PM) Ͻ10 m (PM 10 ) from livestock buildings are rare. 1,2 It is well established that emissions are highly variable both diurnally and seasonally; therefore, measuring mass concentrations continuously or in real time is advantageous. Concentrations of PM 10 , particulate matter Ͻ2.5 m (PM 2.5 ), and TSP were measured during a 6-month measurement campaign in a single-layer barn (SLB) study. 3 Most recently, a six-state U.S. Department of Agriculture study (APECAB: