Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: March 30, 1998
Publication Date: N/A
Technical Abstract: Incubations of manure-amended soil are frequently utilized to evaluate manure N and C availability. An experiment was designed to determine suitable methods of manure sample storage prior to incubation. Dairy slurries were collected from the BARC dairy facility and seven treatments(fresh, frozen 4 wk), refrigerated (1 d, 1 wk, 4 wk), freeze and oven dried)werecompared for effects on N and C mineralization. Rates and extents of N and 6 C mineralization were determined by incubation of manure-amended soil at 25 degrees C under aerobic conditions. The appearance of NH4+ plus NO3- and the production of CO2 were monitored over a 16 wk period. Refrigeration or freezing had little or no effect on manure N content, however freeze and oven drying resulted in large losses of N (ò50%). CO2-C production followed first-order kinetics for all treatments. Immobilization of N was evident in all treatments, however it was more prominent in dried slurries compared to refrigerated or frozen slurries. Nitrification occurred in all treatments and all NH4+ was converted to NO3- by 112 d. Storage conditions had no effect on inorganic N accumulation patterns and net mineralization was minimal. Results indicate that oven and freeze-drying are unsuitable methods of storage, but the mineralization characteristics of manure are not affected by refrigeration or freezing.