TY - JOUR
T1 - Occurrence of anammox on suspended sediment (SPS) in oxic river water
T2 - Effect of the SPS particle size
AU - Xia, Xinghui
AU - Li, Zhihuang
AU - Zhang, Sibo
AU - Zhang, Liwei
AU - Zhang, Ling
AU - Wang, Gongqin
N1 - Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2019/11
Y1 - 2019/11
N2 - Anammox is a newly discovered nitrogen transformation process. However, its role in nitrogen removal in fresh water is far from understood. Here, we hypothesized that anammox could occur on suspended sediment in oxic river water. To test this hypothesis, simulation experiments with a nitrogen stable (15N) isotopic tracer technique were conducted to study the occurrence of anammox on suspended sediment (SPS) in oxic river water, and the effects of the SPS particle size, including <20 μm, 20–63 μm, 63–100 μm, 100–200 μm, and <200 μm (original SPS) size fractions, were investigated. The results showed that anammox occurred in oxic water with SPS due to the existence of low oxygen microsites around/on SPS, and the anammox rate was even higher than the denitrification rate. The anammox rate increased with the SPS concentration, and it was negatively correlated with the particle size and was positively correlated with the organic carbon content of SPS (p < 0.05). The 29N2 produced by anammox in a system containing 1.0 g L−1 SPS with a particle size below 20 μm was 0.27 mg-N/m3·d, which was 5.3 times higher than that produced with a particle size of 100–200 μm. The anammox rate was significantly positively correlated with the anammox bacterial abundance (p < 0.01), and Ca. Brocadia was the dominant species. This study suggests that the SPS in oxic water may be a ‘hotspot’ for the anammox process and that its role in nitrogen removal should be considered in future studies.
AB - Anammox is a newly discovered nitrogen transformation process. However, its role in nitrogen removal in fresh water is far from understood. Here, we hypothesized that anammox could occur on suspended sediment in oxic river water. To test this hypothesis, simulation experiments with a nitrogen stable (15N) isotopic tracer technique were conducted to study the occurrence of anammox on suspended sediment (SPS) in oxic river water, and the effects of the SPS particle size, including <20 μm, 20–63 μm, 63–100 μm, 100–200 μm, and <200 μm (original SPS) size fractions, were investigated. The results showed that anammox occurred in oxic water with SPS due to the existence of low oxygen microsites around/on SPS, and the anammox rate was even higher than the denitrification rate. The anammox rate increased with the SPS concentration, and it was negatively correlated with the particle size and was positively correlated with the organic carbon content of SPS (p < 0.05). The 29N2 produced by anammox in a system containing 1.0 g L−1 SPS with a particle size below 20 μm was 0.27 mg-N/m3·d, which was 5.3 times higher than that produced with a particle size of 100–200 μm. The anammox rate was significantly positively correlated with the anammox bacterial abundance (p < 0.01), and Ca. Brocadia was the dominant species. This study suggests that the SPS in oxic water may be a ‘hotspot’ for the anammox process and that its role in nitrogen removal should be considered in future studies.
KW - Anammox
KW - Greenhouse gases
KW - Nitrogen cycle
KW - River
KW - Suspended sediment
UR - https://www.scopus.com/pages/publications/85067899938
U2 - 10.1016/j.chemosphere.2019.06.161
DO - 10.1016/j.chemosphere.2019.06.161
M3 - 文章
C2 - 31255764
AN - SCOPUS:85067899938
SN - 0045-6535
VL - 235
SP - 40
EP - 48
JO - Chemosphere
JF - Chemosphere
ER -
