Article
Engineering, Environmental
Ehui Tan, Ting-Chang Hsu, Wenbin Zou, Xiuli Yan, Zhixiong Huang, Bin Chen, Yongkai Chang, Zhenzhen Zheng, Liwei Zheng, Min Xu, Li Tian, Shuh-Ji Kao
Summary: The study reveals that sedimentary denitrification is the main nitrogen removal pathway in estuarine environments, with a minor contribution from anammox. Estuarine sediments play a relatively weak role in eliminating nitrogen input, while the excess nitrogen from rivers will eventually be removed through various biological processes.
Article
Environmental Sciences
Jingjie Lin, Anyi Hu, Fenfang Wang, Yiguo Hong, Michael D. Krom, Nengwang Chen
Summary: Storms in subtropical regions like S.E. China have significant impacts on the fluxes of anthropogenic N species from rivers to the coast. Through continuous observations during a storm event in June 2019, it was found that the flux of N greatly increased in the upper Jiulong River Estuary. Additionally, the composition of ammonia-oxidizing archaea changed during the storm, with the dominance of riverine genus Nitrosotenuis.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Yuhong Li, Yang Luo, Jian Liu, Wangwang Ye, Jiexia Zhang, Liyang Zhan
Summary: This study explores the spatial and temporal variations of N2O in the Jiulong River Estuary and finds that it is a strong source of N2O, indicating its significant impact on the environment. The saturation of N2O in the surface water of the estuary varies greatly, ranging from 113% to 2926%, and is influenced by factors such as dissolved inorganic nitrogen (DIN), salinity, and dissolved oxygen concentrations. Despite the decline in DIN inputs since 2011, the study results show that N2O saturation continues to increase.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Jiawei Zhao, Xiangyu Guan, Xiaonan Shi, Wei Guo, Ximing Luo
Summary: This study analyzed the microbial communities in sediments from different levels of the Luan River estuary and found that the abundance and diversity of Nitrospira were highest in the low-level zone and lowest in the high-level zone. The distribution of Nitrospira was also influenced by complex environmental factors such as NH4+, Fe, and Cu cation concentrations.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Environmental Sciences
Jiaojiao Ma, Anyi Niu, Zhenni Liao, Junhao Qin, Songjun Xu, Chuxia Lin
Summary: A 1-year field monitoring program was conducted to study the seasonal variation in N2O fluxes in two different types of mangrove wetlands. The study found that the island-type mangrove wetland had higher levels of heavy metal(loid) contamination and lower levels of salinity compared to the small bay-type wetland. The N2O fluxes showed a similar seasonal variation pattern in both wetlands, with higher fluxes observed in summer. However, the average N2O flux in the island-type wetland was lower than in the small bay-type wetland. The study also found that N2O flux was closely related to soil-borne heavy metal(loid)s and that the activity of anammox bacteria played a key role in affecting the spatial variation of N2O fluxes in the mangrove soils.
MARINE POLLUTION BULLETIN
(2023)
Article
Green & Sustainable Science & Technology
Zhaolei Li, Zhaoqi Zeng, Zhaopeng Song, Dashuan Tian, Xingzhao Huang, Sheng Nie, Jun Wang, Lifen Jiang, Yiqi Luo, Jun Cui, Shuli Niu
Summary: This study provides insights into the geographical variations and primary controlling factors of global soil N2O emissions based on a new dataset of soil N2O emission rates compiled from field observations. It highlights the critical roles of soil N substrates on N2O emissions, contributing to the optimization of process-models for soil N2O emissions.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Ecology
Cynthia Nevison, Peter Hess, Christine Goodale, Qing Zhu, Julius Vira
Summary: This study evaluates the nitrogen cycling in two Earth System Models (ESMs), finding significant differences in global mineralization, immobilization, plant N uptake, nitrification, and denitrification fluxes between the models. The study also suggests underestimated ratios of nitrification:denitrification and highlights the need for more observational constraints on soil nitrogen fluxes.
ECOLOGICAL APPLICATIONS
(2022)
Article
Environmental Sciences
Cheng Chen, Guoyu Yin, Lijun Hou, Min Liu, Yinghui Jiang, Dongsheng Zheng, Dengzhou Gao, Cheng Liu, Yanling Zheng, Ping Han
Summary: This study investigated the effects of sulfamethoxazole (SMX) at near in situ concentration on nitrogen removal processes coupled with nitrification. The results demonstrated that SMX significantly decreased nitrogen removal rates, increased N2O production, and nitrite accumulation. The inhibition of nitrogen transformation functional genes by SMX was more pronounced in heterotrophic denitrification processes.
ENVIRONMENTAL POLLUTION
(2021)
Article
Engineering, Environmental
Yuanyuan Miao, Liang Zhang, Deshuang Yu, Jianhua Zhang, Wenke Zhang, Guocheng Ma, Xinchao Zhao, Yongzhen Peng
Summary: Intermittent aeration is an effective strategy for biological wastewater treatment, allowing for advanced nitrogen removal and reduced energy consumption. It is suitable for partial nitrification and denitrification processes.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Ecology
Cynthia Nevison, Christine Goodale, Peter Hess, William R. Wieder, Julius Vira, Peter M. Groffman
Summary: This study compares model simulations with observations and highlights the need for adjustments to better represent nitrogen fluxes in terrestrial systems.
ECOLOGICAL APPLICATIONS
(2022)
Article
Soil Science
Alexandra Meister, Kristin Bohm, Maria Jesus Gutierrez-Gines, Sally Gaw, Nicholas Dickinson, Brett Robinson
Summary: Plants have the ability to modify the nitrogen cycle in soil through various mechanisms, such as N uptake, root exudation, and nitrification inhibition. This study aimed to investigate the impact of New Zealand native plant species on the abundance of nitrifying and denitrifying microorganisms in the soil. The results showed that plant species had a significant effect on the abundance of certain functional genes and the chemical properties of the soil.
APPLIED SOIL ECOLOGY
(2023)
Review
Environmental Sciences
Babita Aryal, Roshni Gurung, Aline F. Camargo, Gislaine Fongaro, Helen Treichel, Bandita Mainali, Michael J. Angove, Huu Hao Ngo, Wenshan Guo, Shukra Raj Puadel
Summary: The acceleration of the nitrogen cycle and nitrous oxide (N2O) emissions at an unprecedented rate has serious implications for the global ecosystem and climate change. The paper reviews how anthropogenic activities have disrupted the nitrogen cycle and estimates the future N2O-N emissions. The study emphasizes the importance of holistic mitigation strategies, policy reforms, and public awareness to tackle N2O emissions and their consequences.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Yongkai Chang, Guoyu Yin, Lijun Hou, Min Liu, Yanling Zheng, Ping Han, Hongpo Dong, Xia Liang, Dengzhou Gao, Cheng Liu
Summary: This study investigated the rates of denitrification and anammox in coastal sediments off the north East China Sea, finding that nitrate was a critical factor influencing the ratio between coupled and uncoupled nitrogen removal, and that ammonia oxidizing bacteria may play an important role in the coupled nitrification-denitrification process. These results emphasize the importance of nitrification in nitrogen removal in coastal ecosystems.
JOURNAL OF SOILS AND SEDIMENTS
(2021)
Article
Environmental Sciences
Lifei Sun, Chao Wang, Haoming Yu, Dongwei Liu, Benjamin Z. Houlton, Shaofeng Wang, Xiangfeng Zeng, Edith Bai, Yunting Fang, Yongfeng Jia
Summary: Through molecular and isotopic methods, the study found that denitrification is the dominant pathway of sedimentary N-2 production along the continental shelf of China, while anaerobic ammonium oxidation rate is correlated with hzsB gene abundance; temperature and dissolved oxygen regulate denitrification rates by influencing biotic factors such as functional genes and microbial biomass.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Microbiology
Rohini Mattoo, B. M. Suman
Summary: Soil microorganisms play a crucial role in regulating the nitrogen cycle and impacting climate change. These microorganisms contribute to the transformation of nitrogen into various bio-available forms, which are essential for metabolic reactions. Recent discoveries have furthered our understanding of microbial involvement in nitrogen cycle reactions in soil and aquatic systems, shedding light on their influence on climate change. This review also emphasizes how anthropogenic activities disrupt the nitrogen cycle and suggests the potential use of beneficial microbes for nitrogen replenishment in agricultural ecosystems.
FEMS MICROBIOLOGY LETTERS
(2023)