Bisolation And Identification Of Ammonia Nitrogen-Degrading Microbe And Their Inhibition Effect On Ammonia Volatilization From Chicken Manure

Ammonia(NH3) emission has become a significant environmental and public concern. One the one hand, it harms human and animal health immediate. For instance, it contributes to the formation of small aerosol particles(PM2.5) as well as the respiratory disease. For another, it can result in ecosystem acidity and eutrophication though the reaction with atmospheric acidic compounds.This paper was conducted to screen specialized microbe with ability of ammonia nitrogen removal.Experiment 1: Ammonium sulfate was used as the sole nitrogen source to isolate the ammonia nitrogen-degrading microbe from chicken manure. Fifteen strains with the ability of ammonia removal were isolated from the chicken manure after enrichment, separation and screening process. Among them there are four strains named LSA, YSA, NGH and HL showed high efficient degradation ability. And these four strains were identified as Candida krusei、Candida rugosa、Pichia farinosa、Paecilomyces variotii respectively according to its morphology, physiological and biochemical identification and molecular biology method.Experiment 2: Single factor experiments were conducted to identify its optimum degradation conditions. The temperature was set as 20℃、25℃、30℃、35℃ and 40℃; pH was set as 3、4、5、6、7、8 and 9; The starch, mannitol, sodium citrate, sodium acetate, glucose and sodium bicarbonate was used as sole carbon source, respectively;C/N was set as 5, 10, 20 and 40;initial ammonia concentration was set as 100、300、600 and 1200mg/L. The results showed that optimum conditions for strain LSA is 35℃, pH 3-7, glucose as carbon source, C/N 20. Strain YSA was most effective with the conditions of 35℃, pH 3-7, sodium acetate as carbon source, C/N 20. For strain NGH, the optimal condition was 30-35℃, pH 3-7, glucose as carbon source, C/N 10. The optimum conditions for strain HL was 35℃, pH 4-7, glucose as carbon source, C/N 40. All of the strains could survival well at wide initial ammonia concentrations from 100mg/L to1200mg/L. Rapid degradation period of strains were in accordance with its logarithmic phase. When the initial ammonia concentration was 300mg/L, the ammoniac nitrogen degradation rate of strain LSA, YSA, NGH and HL was 71.83%, 31.89%, 43.01% and 80.53%. When the initial ammonia concentration was 1200mg/L, the ammoniac nitrogen degradation rate of strain LSA, YSA, NGH and HL was 57.44%,18.05%,35.46%,39.80%.Experiment 3: Ammonia emissions from chicken manure inoculated with strain LSA, YSA, NGH, HL and yeast mixture was studied. Ammonia gas, ammonia nitrogen and total nitrogen from chicken manure after fermentation were determinated. Results indicated that the ammonia volatilized from treatment groups were less than that from control groups except the YSA treatment groups. The HL treatment groups worked best in 96 h after inoculation. On the contrary yeast treatment groups, include LSA, NGH and yeast mixture groups, worked best in 24h-48 h after inoculation. In addition, ammonia nitrogen of treatment groups from chicken manure after fermentation was lower compared with control groups.It can be concluded that Candida kruse LSA,Pichia farinos NGH,Candida rugosa YSA �'�Paecilomyces variotii HL can removal NH4+-N effectively. All of the strains inoculated into chicken manure can reduce the NH3 emission rate except strain YSA.