Article
Environmental Sciences
Joseph K. Fackrell, Tamara E. C. Kraus, Megan B. Young, Carol Kendall, Sara Peek
Summary: River deltas are increasingly impacted by human inputs of nitrogen, which can lead to harmful phenomena. A study on the Sacramento-San Joaquin Delta in California used a multi-tracer approach to examine nitrogen sources and processes. Results showed that the Sacramento River and its distributaries primarily received nitrogen in the form of NH4+ from treated wastewater effluent, and there were significant biogeochemical processes that affected the downstream transport of nitrogen. The study also highlighted the diversity in nitrogen dynamics and the utility of a multi-tracer approach in complex river delta environments.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Wei Wen Wong, Ian Cartwright, Seng Chee Poh, Perran Cook
Summary: The study utilized stable and radiogenic isotopes along with nitrogen concentrations to evaluate nitrogen sources and cycling processes in Port Phillip Bay, Australia, highlighting the importance of terrestrial-coastal interactions and submarine groundwater discharge as significant pathways of nitrogen inputs. The high nitrogen concentrations were attributed to nitrified sewage effluent, atmospheric deposition, and groundwater and sewage inputs. More efforts are needed to quantify the relative contributions of multiple nitrogen input pathways in future research.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Weiguo Zhou, Junde Dong, Dewen Ding, Lijuan Long, Anning Suo, Xiancheng Lin, Qingsong Yang, Liyun Lin, Yanying Zhang, Juan Ling
Summary: This study investigated the impact of inorganic nitrogen on the rhizosphere microbiome of seagrass through high-throughput sequencing, revealing shifts in relative abundance of specific microbial communities under inorganic nitrogen enrichment. Additionally, it was found that seagrass photosynthetic characteristics were influenced by different nitrogen sources.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Shangjun Cai, Qibin Lao, Guangzhe Jin, Chunqing Chen, Xin Zhou, Qingmei Zhu, Xuan Lu
Summary: This study investigated the sources and biogeochemical processes of nitrate in Xi Bay, a coastal bay in Beibu Gulf, South China, using dual isotopes. The results showed that human activities, such as industrial and port activities, were the main drivers of nutrient enrichment in the bay. Microbial nitrification and external sources, including sewage, manure, soil N, and fertilizer, were identified as the dominant nitrate sources. Atmospheric deposition had a minor contribution to nitrate pollution in the bay.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Plant Sciences
Yi Hu, Robert D. Guy, Raju Y. Soolanayakanahally
Summary: Nitrogen isotope discrimination (ΔN-15) can be used as an indicator of nitrogen use in plants. In this study, a simple isotope mass balance (IMB) model was used to analyze the nitrogen use efficiency of different canola lines. The results showed that commercial hybrids had a higher capability to utilize ammonium as their sole nitrogen source compared to open-pollinated lines.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Engineering, Civil
Zhipeng Gao, Haicheng Weng, Huaming Guo
Summary: The origin and co-cycling of nitrogen species in arsenic-prone groundwater remain poorly understood, which could affect arsenic behavior. This study investigated the geochemical and multi-isotopic characteristics of groundwater in different redox environments to reveal the effects of nitrogen cycling on arsenic mobility.
JOURNAL OF HYDROLOGY
(2021)
Article
Plant Sciences
Anh Quang Dinh, Asif Naeem, Amit Sagervanshi, Monika A. Wimmer, Karl H. Muhling
Summary: The study found that at low boron supply, plants fed with nitrate and ammonium had similar B-10 uptake rates, accumulation, and xylem B-10 concentrations, but these attributes were reduced at high boron supply. Ammonium-induced acidity and nitrate-induced alkalinization led to altered B distribution between roots and shoots as well as different B transport mechanisms in plants.
PLANT PHYSIOLOGY AND BIOCHEMISTRY
(2021)
Article
Environmental Sciences
Abdulhalim Zaryab, Hamid Reza Nassery, Kay Knoeller, Farshad Alijani, Eddy Minet
Summary: This study investigates the geochemistry and stable isotope composition of the Kabul urban aquifer, the main source of drinking water for Kabul city's inhabitants. The findings suggest that nitrate pollution in the aquifer primarily originates from sewage rather than artificial fertilizer. The results highlight the importance of improving sewage collection systems in the Kabul Plain.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Civil
Guillaume Lorette, Mathieu Sebilo, Damien Buquet, Roland Lastennet, Alain Denis, Nicolas Peyraube, Veronique Charriere, Jean-Christophe Studer
Summary: Determining the origins of nitrate is crucial for improving groundwater management in hydrogeological catchments. This study used stable isotopic composition analysis to identify the sources of nitrate in a karst system. The results showed that the upper Jurassic karst confined aquifer and the upper Cretaceous unconfined aquifer have the same nitrate sources. Additionally, the study found that the lower aquifer can be fed by the upper Cretaceous unconfined aquifer, contrary to previous belief. Overall, this work provides important insights for the understanding and management of water quality in karstic hydrogeological catchments.
JOURNAL OF HYDROLOGY
(2022)
Article
Engineering, Civil
Hyejung Jung, Yun S. Kim, Jisu Yoo, Bumsung Park, Jeonghoon Lee
Summary: A multi-isotopes approach combining stable nitrate isotopes (delta N-15(NO3) and delta O-18(NO3)) with stable water isotopes (delta O-18(H2O) and delta H-2(H2O)) can help identify nitrogen sources and understand transformation processes in river water systems. Seasonal variations have a significant impact on stable isotope values, leading to uncertainties in estimating the contribution of effluent to the water system.
JOURNAL OF HYDROLOGY
(2021)
Review
Agricultural Engineering
Jae Bok Heo, Yong-Suk Lee, Chung-Han Chung
Summary: This study explores the potential of marine plants, including macroalgae and seagrass, as biorenewable feedstocks for producing 2,5-furandicarboxylic acid (FDCA), a versatile platform chemical. The use of ionic liquid-based solvents (ILS) and deep eutectic solvent (DES) systems, as well as biomodification strategies involving target enzyme-encoding genes, are proposed to enhance FDCA production. The findings pave the way for eco-friendly biorefineries and biorenewable plastics.
BIORESOURCE TECHNOLOGY
(2023)
Article
Environmental Sciences
Risto Vesala, Heikki Kiheri, Erik A. Hobbie, Netty van Dijk, Nancy Dise, Tuula Larmola
Summary: Continuous nitrogen addition over 14 years in ombrotrophic peatlands affected ericoid mycorrhizal (ERM) shrubs at Whim Bog in Scotland. High doses of ammonium alleviated nitrogen deficiency in Calluna vulgaris and Erica tetralix, while low doses of ammonium and nitrate improved plant phosphorus nutrition. Root acid phosphatase activities positively correlated with foliar nitrogen to phosphorus ratios, suggesting enhanced phosphorus uptake due to improved nitrogen nutrition.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Efstratios Kelepertzis, Ioannis Matiatos, Fotini Botsou, Christina Antonopoulou, Ioannis Lappas, Elissavet Dotsika, Vladislav Chrastny, Pascal Boeckx, Sotirios Karavoltsos, Michael Komarek
Summary: The Atalanti basin in central Greece is facing groundwater quality deterioration threats due to both natural and human-induced contamination sources. This study used a combination of statistical and hydrogeochemical techniques, as well as stable isotope compositions, to investigate the origin of salinity and nitrate contamination. The findings showed that irrigation return flow and marine aerosols were the main contributors to high salinity, while fertilizers and sewage waste were the dominant sources of nitrate. The study also revealed the influence of redox conditions on the biogeochemical transformations of nitrogen species and the mobilization of chromium (VI).
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Wentao Wang, Zhiming Yu, Xiuxian Song, Lianbao Chi, Zaixing Wu, Yongquan Yuan
Summary: This study estimated the source apportionment of nitrate on the East China Sea (ECS) shelf by analyzing the nitrogen and oxygen stable isotopes in nitrate and essential parameters. It found that the biogeochemical processes of nitrate were weak in winter and intensive in spring, with significant assimilation accompanying nitrification. The study also revealed the contributions of different sources, such as the Changjiang Diluted Water and Kuroshio Subsurface Water, and the seasonal variations in nitrate inputs from different regions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Geochemistry & Geophysics
Guitao Shi, Hongmei Ma, Zhuoyi Zhu, Zhengyi Hu, Zhenlou Chen, Su Jiang, Chunlei An, Jinhai Yu, Tianming Ma, Yuansheng Li, Bo Sun, Meredith G. Hastings
Summary: The study found that atmospheric nitrate is mainly concentrated on intermediate size particles, with much higher concentrations observed in the northern hemisphere compared to high southern latitudes. Isotope analysis indicated that elevated atmospheric nitrate in coastal areas is associated with human activities, while in high southern latitudes, it is influenced by precursor Antarctic snowpack emissions.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)