100073 Temporal Changes of Nitrification and Nitrifying Microbes Induced By Dicyandiamide Application to a Soil Applied with Anaerobic Digestion Effluents.

Poster Number 177-431

See more from this Division: SSSA Division: Soil Biology and Biochemistry
See more from this Session: Soil Biology and Biochemistry Poster I (includes student competition)

Monday, November 7, 2016
Phoenix Convention Center North, Exhibit Hall CDE

Shuta Karino, Environmental Engineering, Soka University, Hachioji, TOKYO, JAPAN and Shinjiro Sato, Environmental Engineering, Soka University, Hachioji-shi, Tokyo, JAPAN
Abstract:
Anaerobic digestion effluents (ADEs) are remaining liquid residuals after organic biomass are anaerobically digested. The ADEs contain abundant plant nutrients such as nitrogen (N) and potassium, and have proven to have similar fertilizer effects as chemical fertilizers. However, it has also been reported that ADEs application to soils can cause more NO3--N leaching and NO emission from soils compared to chemical fertilizers. Reducing NO3--N leaching and N2O emission from ADEs-applied soils needs to be improved for alternative use of ADEs to chemical fertilizers. NO3--N and N2O are produced by nitrification in soils, presumably mediated by ammonia-oxidizing bacteria (AOB) and archaea (AOA). Therefore, in this study, an incubation study was conducted to examine the effect of nitrification inhibitor on nitrification and the dynamics of microbes in a soil applied with ADE.

A soil used in this study was Typic Dystrochrept (Tokyo, Japan), oven-dried, and sieved by 2 mm. The ADEs were derived from food waste (FW), cow manure (CM), and sewage water (SW) digestion plant, and applied as 140 kg N ha-1 based on N recommended rate for Japanese mustard spinach (Brassica rapa). Dicyandiamide (DCD) was used as nitrification inhibitor, applied at 10% of total N applied from chemical fertilizer (CF) or ADE. Nine treatments were included: no amendments, CF only, ADEs only (FW, CM or SW), CF with DCD (CF+DCD), and ADEs with DCD (FW+DCD, CM+DCD or SW+DCD). Soil NH4+-N, NO3--N, and pH were analyzed on 0, 3, 7, 14, 21, 28, 42 and 56 day, and AOB and AOA abundance were analyzed on 0, 7, 14, 28 and 56 day of the incubation.

High NH4+-N and low NO3--N in the soil are expected accordingly to decreased AOB and AOA abundance in the soil applied with DCD.

See more from this Division: SSSA Division: Soil Biology and Biochemistry
See more from this Session: Soil Biology and Biochemistry Poster I (includes student competition)