Article
Geosciences, Multidisciplinary
Junfeng Wang, Xinghui Xia, Shaoda Liu, Sibo Zhang, Ling Zhang, Chenrun Jiang, Zhenrui Zhang, Yuan Xin, Xin Chen, Jing Huang, Jiaao Bao, William H. McDowell, Greg Michalski, Zhifeng Yang, Jun Xia
Summary: This study finds that the water column plays an important role in nitrogen cycling processes in rivers, which is often neglected. Observations across six river networks in China show that the water-air and sediment-water fluxes of N-2 and N2O decrease, while the water column production increases with stream order. The water column contribution increases with stream order and accounts for more than 50% in rivers above fifth order. Neglecting water column processes would lead to an underestimation of N removal and N2O emissions by approximately 50% for these river networks.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Dengzhou Gao, Lijun Hou, Min Liu, Yanling Zheng, Guoyu Yin, Yuhui Niu
Summary: Studying N2O production and consumption processes along an intertidal elevation gradient can improve the understanding of N2O dynamics among coastal wetlands. The results showed that N2O emission rates were higher in high tidal zones compared to middle and low tidal zones. Gross N2O production and consumption rates were greater in high and low tidal zones, whereas N2O consumption proportions generally increased from high to low tidal zones. Bacterial denitrification was the dominant pathway, although NH2OH oxidation/fungal denitrification also contributed substantially to N2O production in high tidal flats. Changes in N2O dynamics along the elevation gradient were affected by carbon and nitrogen substrate availabilities as well as the redox environments.
ENVIRONMENTAL RESEARCH
(2022)
Article
Engineering, Environmental
Minpeng Hu, Bingqing Li, Kaibin Wu, Yufu Zhang, Hao Wu, Jia Zhou, Dingjiang Chen
Summary: Estimates of riverine N2O emission are uncertain due to lack of knowledge on sources and fates. Using a mass-balance model, this study found that N2O in rivers mainly originates from groundwater, surface runoff, and in-stream production, with losses mainly occurring through atmospheric release and complete denitrification.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Biodiversity Conservation
Huanhuan Wei, Xiaotong Song, Yan Liu, Rui Wang, Xunhua Zheng, Klaus Butterbach-Bahl, Rodney T. Venterea, Di Wu, Xiaotang Ju
Summary: Oxygen dynamics play a key role in controlling nitrous oxide (N2O) production processes in arable soils. Bacterial denitrification is the primary source of N2O emissions during the hot-wet summer, while nitrification or fungal denitrification contribute to about 50.0% of total emissions during the cold-dry winter. The findings help improve process models and develop targeted mitigation measures for N2O emissions.
GLOBAL CHANGE BIOLOGY
(2023)
Review
Environmental Sciences
Waqas Qasim, Longlong Xia, Shan Lin, Li Wan, Yiming Zhao, Klaus Butterbach-Bahl
Summary: Excessive nitrogen fertilizer use in greenhouse vegetable production leads to low nitrogen use efficiency and high nitrogen losses, which can be mitigated by reducing fertilizer application rates.
ENVIRONMENTAL POLLUTION
(2021)
Article
Agriculture, Multidisciplinary
Armwell Shumba, Regis Chikowo, Marc Corbeels, Johan Six, Christian Thierfelder, Remi Cardinael
Summary: This study conducted in Zimbabwe examines the impact of conservation agriculture principles on greenhouse gas emissions. The results show that mulching treatments lead to higher nitrous oxide emissions at one site, while rotation treatments result in higher nitrous oxide emissions at the other site. Additionally, the study finds that nitrous oxide loss is low in low nitrogen input cropping systems.
AGRICULTURE ECOSYSTEMS & ENVIRONMENT
(2023)
Article
Engineering, Environmental
Qianqian Tu, Yiyihui Hong, Yinying Zhu, Hong Cheng, Xiaoliu Huangfu, Qiang He
Summary: In this study, a simplified mathematical model was developed and applied to the BAF system, optimizing operational parameters and successfully predicting N2O emissions and nitrogen removal.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Engineering, Environmental
Yanying He, Yingrui Liu, Min Yan, Tianhang Zhao, Yiwen Liu, Tingting Zhu, Bing-Jie Ni
Summary: Long-term exposure to PET microplastics in wastewater reduces both N2O production and reduction during denitrification and nitrification processes, but overall N2O emission factors remain stable. Microplastics alter microbial activity pathways and N2O production pathways significantly under stress.
Article
Engineering, Environmental
Rui Yang, Lin-jiang Yuan, Ru Wang, Zhi-xian He, Xi Chen
Summary: This study focuses on the metabolism of N2O in biological wastewater treatment, finding that the main metabolic mechanism is heterotrophic denitrification, influenced by the amount of organic matter and pH value. Under aerobic conditions, N2O emissions mainly come from nitrifiers.
JOURNAL OF WATER PROCESS ENGINEERING
(2021)
Article
Environmental Sciences
Iris Feigenwinter, Lukas Hortnagl, Nina Buchmann
Summary: This study investigated the drivers of net ecosystem N2O and CH4 fluxes in a temperate grassland and found that reducing nitrogen fertilizer application and increasing the proportion of leguminous plants are effective measures to reduce N2O emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Forestry
Xin Rao, Chang-An Liu, Jian-Wei Tang, Yu Nie, Ming-Yue Liang, Wei-Jun Shen, Kadambot H. M. Siddique
Summary: Rubber plantations cover a vast area globally, and introducing leguminous shrubs can help reduce CO2 and CH4 emissions while increasing N2O emissions, ultimately improving soil environments. As trees in rubber plantations age, there is a significant decrease in annual emissions of CO2, N2O, and CH4, with rubber-leguminous shrub systems showing potential for enhancing soil organic carbon sequestration.
FOREST ECOLOGY AND MANAGEMENT
(2021)
Article
Multidisciplinary Sciences
Chen Wang, Xuehong Ma, Gang Wang, Guitong Li, Kun Zhu
Summary: This study used O-2-specific planar optodes to visualize the spatial and temporal distribution of oxygen in soils treated with biological soil disinfestation (BSD), revealing its impact on emissions of N2O and CH4. The decrease in oxygen levels in soil was rapid, but significantly affected by the addition of straw and biochar. Co-application of biochar with straw delayed the development of anoxia and reduced emissions of N2O and CH4. Understanding soil O-2 dynamics is crucial for optimizing organic amendments in BSD techniques.
SCIENTIFIC REPORTS
(2021)
Article
Biotechnology & Applied Microbiology
Xinyu Wan, Eveline I. P. Volcke
Summary: This study applied mathematical modeling to analyze the formation and emission dynamics of N2O in a partial nitritation-anammox reactor, and developed strategies to mitigate N2O emissions. The model accurately predicted and characterized N2O emissions through calibration and validation.
BIOTECHNOLOGY AND BIOENGINEERING
(2022)
Article
Environmental Sciences
Morten Lykkegaard Christensen, Anne Hojmark Jakobsen, Cecilie Sofie Kragelund Hansen, Mads Skovbjerg, Rikke Bruun Munk Andersen, Mette Dam Jensen, Kim Sundmark
Summary: This article describes a wastewater treatment plant designed to focus equally on energy production, water quality, and reduced emissions of greenhouse gases. The plant utilizes a disk filter to remove carbon during primary treatment, followed by hydrolysis and centrifugation to produce a hydrolysate centrate that can be used for secondary wastewater treatment or biogas production.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Civil
Madison K. Flint, Jonathan B. Martin, Tatiana Summerall, Adrian Barry-Sosa, Brent C. Christner
Summary: The presence of anthropogenic reactive nitrogen species in the environment may lead to an increase in atmospheric nitrous oxide concentrations, contributing to global warming and ozone depletion. The cycling of N2O in karst aquifers is complex and influenced by factors such as dissolved organic carbon and dissolved oxygen concentrations, as well as the residence time for nitrogen processing in the subsurface.
JOURNAL OF HYDROLOGY
(2021)