A perfusion technique was used to study the effects of l) simulated acid rain on the mineralization and nitrification of glycine (NH 2-N) or ammonium sulfate (NH4-N) by adjusting the pH of the perfusates to 3.0, 2.5, or 2.0 with H 2S0 4 ; and 2) 0, 50, I 00, 500, and I ,000 1-1-g Cd!g dry weight of soil on the mineralization and nitrification of NH 2-N, both in soil adjusted with H 2S04 to pH 3...

The spatial distribution and diversity of archaeal and bacterial ammonia oxidizers (AOA and AOB) were evaluated targeting amoA genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling. Here we found high spatial heterogeneity in the nitrification rate and abundance of ammonia oxidizers in the five sampling sites. The bacterial amoA gene was numerical...

In the external nitrification (EN) biological nutrient removal (BNR) activated sludge (AS) system, the nitrification process is removed from the BNR activated sludge system and performed ‘externally’ on an integrated nitrifying trickling filter (NTF). As such, optimum design and operation of the NTF is essential for reliable performance of the ENBNRAS system. Although information on the design ...

Removal of ammonia nitrogen and nitrate nitrogen by an heterotrophic nitrification-aerobic denitrification strain is an economical and effective method. In this article, a kind of heterotrophic nitrification-aerobic denitrification strain which has aerobic denitrification and heterotrophic nitrification ability was selected, and then was identified as rhodococcus sp. by 16S rRNA sequencing anal...

Both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) play an important role in nitrification in terrestrial environments. Most often AOA outnumber AOB, but the relative contribution of AOA and AOB to nitrification rates remains unclear. The aim of this experiment was to test the hypotheses that high nitrogen availability would favor AOB and result in high gross nitrificatio...

Nitrification is a necessary and often limiting process in animal waste treatment for removal of nitrogen as N2 through biological nitrification/denitrification systems. We evaluated three technologies for enhancing nitrification of pig lagoon wastewater prior to denitrification: overland flow, trickling filter, and a bioreactor using nitrifying pellets. The overland flow system consisted of a ...