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Previous studies have indicated that soil properties and texture could lead to differences in N mineralization from applied organic materials. We conducted a 100-day (d) incubation study to measure net N mineralized from feather meal (14–0.1–0.1) and pellet mix (10–1–6) at 150 mg N kg soil −1 (approximately 72 kg N ha−1) incorporated into four common southeastern soils: Cecil 1, Cecil 2, Greenville, and Tifton. A second 23-d study was conducted to determine pH dynamics and the potential for ammonia volatilization from the same soils and materials. There were no differences in net N mineralized from pellet mix among soils, but net N mineralized from feather meal was lower in Greenville soil, which had the greatest clay content. Analysis of the first-order dynamics of N mineralization indicated that even in soils that differ in clay content it may be possible to describe N mineralization from feather meal and pellet mix with a single model. Our results also suggest that the effect of pH on the N mineralization dynamics of these fertilizers may be more important than the effect of clay content. No ammonia loss was observed regardless of soil texture, soil pH buffering capacity, or initial soil pH. [ABSTRACT FROM AUTHOR]

Flumioxazin is a preemergence, N -phenylpththalimide herbicide that can be applied to control a broad spectrum of weeds in a variety of cropping systems. Limited information exists concerning the environmental fate of flumioxazin, therefore the present studies investigated the kinetic behavior of flumioxazin in soil and aqueous solution using field and analytical techniques to establish its degradation properties. Flumioxazin half-life in a Greenville sandy clay loam and Faceville loamy sand was 26.6 d. Flumioxazin was determined to have a groundwater ubiquity score of 1.79, indicating a low leachability potential. There was an inverse correlation between flumioxazin concentration in soil, rainfall, and solar radiation. There was no direct correlation between flumioxazin concentration and soil temperature. Flumioxazin activation energy was 58.4 (±1.2) kJ mol−1 with a Q 10 value of 2.2. Even at the lowest amount of solar radiation and soil temperature, the energy from these environmental measures exceeded the activation energy needed for flumioxazin degradation. Flumioxazin stability in solution and field dissipation indicate that, with the input of thermal energy, degradation can be rapid. [Display omitted] • Flumioxazin half-life in two Georgia soils was determined to be 26.6 d with a GUS score of 1.79. • The activation energy of flumioxazin was 58.4 (±1.2) kJ mol−1 with a Q 10 value of 2.2. • Flumioxazin concentration in soil decreased over time as rainfall and solar radiation increased. • Flumioxazin stability in aqueous solution indicated that degradation increased as the input of thermal energy rose. [ABSTRACT FROM AUTHOR]