Review
Microbiology
Kendra A. Turk-Kubo, Mary R. Gradoville, Shunyan Cheung, Francisco M. Cornejo-Castillo, Katie J. Harding, Michael Morando, Matthew Mills, Jonathan P. Zehr
Summary: This review paper provides a comprehensive understanding of the biology, ecology, and biogeography of marine non-cyanobacterial diazotrophs (NCDs) through the synthesis of multiple datasets. The authors discuss recent advances in studying the diversity, distribution, and ecophysiology of NCDs, as well as their significance to the nitrogen cycle in well-lit oxygenated euphotic waters.
FEMS MICROBIOLOGY REVIEWS
(2023)
Article
Environmental Sciences
Yanpei Zhuang, Yangjie Li, Ling Chen, Haiyan Jin, Di Qi, Jianfang Chen
Summary: The spatial variability of ammonium concentrations along repeat transects on the Chukchi shelf from 2012 to 2018 was studied. Two distinct near-bottom high ammonium pools (>1 μmol/kg) were identified at 67.5 degrees N and 72.5 degrees N in all years. The accumulation of ammonium in these regions is primarily influenced by a combination of biogeochemical processes (such as dynamic bacterial remineralization of organic matter) and physical controls (such as a strong density-contrast barrier limiting upward mixing of ammonium). The expansion of the ammonium pool on the shelf may have potential impacts on the structure and productivity of the ecosystem on the Chukchi shelf.
MARINE ENVIRONMENTAL RESEARCH
(2023)
Article
Environmental Sciences
You-You Hao, Zhuo-Yi Zhu, Fu-Tao Fang, Tihana Novak, Milan Cankovic, Enis Hrustic, Zrinka Ljubesic, Ming Li, Jin-Zhou Du, Rui-Feng Zhang, Blazenka Gasparovic
Summary: Estuaries play a crucial role in modifying the concentration and composition of riverine nutrients and organic matter, affecting the flux of these materials to coasts. The study of the Wenchang and Krka River estuaries highlights the significance of estuarine processes in removing nitrogen and assimilating organic materials, with implications for nutrient yields from eutrophic rivers in ocean studies.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Biodiversity Conservation
Janet B. Walker, David J. Gillett, Martha Sutula
Summary: Estuaries, lagoons, and embayments are key components of the coastal ecosystem and are commonly affected by eutrophication. This study identified and validated sediment organic carbon and nitrogen concentrations associated with changes in macrobenthic community composition in the Southern California Bight. The findings provide a useful approach for managing coastal ecosystems and setting targets for biostimulatory stressors.
ECOLOGICAL INDICATORS
(2022)
Article
Environmental Sciences
Yongquan Wang, Huizeng Liu, Guofeng Wu
Summary: Satellite ocean color remote sensing can be used to detect particulate organic nitrogen (PON) concentrations in the global ocean, with AOP-based models showing the best performance. PON models were developed to explore the monthly variations of PON concentrations in the global ocean, and further studies will investigate the spatiotemporal variations and driving forces of oceanic PON.
FRONTIERS IN MARINE SCIENCE
(2022)
Review
Polymer Science
Dennis A. Hansell, Monica Orellana
Summary: Marine dissolved organic matter (DOM) holds approximately 660 billion metric tons of carbon, serving as a major carbon reservoir exchangeable with the atmosphere. While the global dynamics of this pool have been better understood in recent decades, the molecular-level control and the role of microgels in this system remain poorly known. This manuscript provides a global context for further insights into this large pool of marine DOM.
Review
Agronomy
Jagdish K. Ladha, Mark B. Peoples, Pallavolu M. Reddy, Jatish C. Biswas, Alan Bennett, Mangi L. Jat, Timothy J. Krupnik
Summary: This review examines the importance of biological nitrogen fixation in crop production and the contribution of nitrogen sources on a global scale. Strategies to enhance the efficiency of biological nitrogen fixation are discussed, along with the challenges and potential of introducing biological nitrogen fixation into conventional and alternative crop management systems.
FIELD CROPS RESEARCH
(2022)
Article
Environmental Sciences
Kyra A. St. Pierre, Brian P. V. Hunt, Ian J. W. Giesbrecht, Suzanne E. Tank, Ken P. Lertzman, Justin Del Bel Belluz, Margot L. Hessing-Lewis, Angeleen Olson, Tyrel Froese
Summary: Coastal waters are biogeochemical hotspots globally, and the Northeast Pacific Coastal Temperate Rainforest (NPCTR) region is no exception. This study investigates the relative contributions of different ecosystems to surface ocean organic matter pools in the NPCTR, using a four-year dataset. The results show that the contributions vary seasonally and spatially, highlighting the need to consider coastal waters as integrated land-ocean meta-ecosystems.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
J. Severino P. Ibanhez, Xose Anton Alvarez-Salgado, Carlos Rocha
Summary: Coastal groundwater contamination due to fertilizers has led to submarine groundwater discharge (SGD) being considered a significant source of dissolved inorganic nitrogen (DIN) to the ocean. Observations show increased availability of NO3- in the subterranean estuary (STE) with DIN enrichment, leading to enhanced metabolic turnover of sedimentary organic matter.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Geochemistry & Geophysics
Yong Du, Huyue Song, Stephen E. Grasby, Teng Xing, Haijun Song, Li Tian, Daoliang Chu, Yuyang Wu, Jacopo Dal Corso, Thomas J. Algeo, Jinnan Tong
Summary: Global warming, oceanic anoxia, and carbon cycle perturbations characterized the end-Permian to Middle Triassic interval. Nitrogen isotope data indicate the presence of nitrate-limited and ammonium-dominated conditions in Early Triassic oceans, contributing to delayed marine biotic recovery. The nitrogen cycle in South China experienced earlier and more rapid changes than northwestern Pangea, with a return to aerobic conditions during the Middle Triassic.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Environmental Sciences
J. Blake Clark, Antonio Mannino, Robert G. M. Spencer, Suzanne E. Tank, James W. Mcclelland
Summary: Long-term increases in Arctic river discharge have been observed, and there are positive correlations between dissolved organic carbon (DOC) concentration, river discharge, and chromophoric dissolved organic matter (CDOM) content in the largest Arctic rivers. The study estimated chromophoric DOC (CDOC) concentrations in six Arctic rivers using data collected from 2009 to 2019. The modeled results showed an increase in DOC and CDOC exports, with CDOC increasing at a faster rate than total DOC.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Soil Science
Wenting Jiang, Haikuo Zhang, Yunying Fang, Youchao Chen, Shoujia Zhuo, Zhihao Chen, Chenfei Liang, Lukas Van Zwieten, Shenglei Fu, Yongfu Li, Bing Yu, Yanjiang Cai, Scott X. Chang
Summary: Deposition of atmospheric nitrogen increases soil nitrous oxide emissions, and the commonly used understory nitrogen application methods underestimate the actual impacts due to overlooking nitrogen interception by forest canopies. Our study compared different nitrogen deposition simulation approaches and forms of nitrogen in a Moso bamboo forest, and found that the cumulative nitrous oxide emissions were higher in understory nitrogen application treatments compared to canopy treatments, with greater emissions under inorganic nitrogen application. Considering canopy processes is important for future studies on nitrogen deposition and soil nitrous oxide emissions.
Article
Environmental Sciences
Dong-Young Back, Sun-Yong Ha, Brent Else, Mark Hanson, Samantha F. Jones, Kyung-Hoon Shin, Agnieszka Tatarek, Jozef M. Wiktor, Nazim Cicek, Shah Alam, C. J. Mundy
Summary: The study found that the Kitikmeot Sea is one of the most nutrient-depleted regions in the Arctic Ocean, with local primary production in Cambridge Bay significantly influenced by wastewater effluent. Despite not yet being eutrophic, caution is advised for the rapid response of the marine system to wastewater release, with a strong recommendation to develop a research and monitoring plan for the bay.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
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
Environmental Sciences
Maren Voss, Eero Asmala, Ines Bartl, Jacob Carstensen, Daniel J. Conley, Joachim W. Dippner, Christoph Humborg, Kaarina Lukkari, Jolita Petkuviene, Heather Reader, Colin Stedmon, Irma Vybernaite-Lubiene, Nicola Wannicke, Mindaugas Zilius
Summary: Coastal waters exhibit strong gradients in dissolved organic matter (DOM) quantity and characteristics, which originate from terrestrial inputs and autochthonous production. Different coastal systems show varying impacts on DOM, influenced by land use in the catchments, suggesting that the ratio of DOC:DON and DOC:DOP in tributaries may be affected.
Article
Green & Sustainable Science & Technology
Nicholas E. Ray, Robinson W. Fulweiler
Summary: The study found that oysters play a role in removing excess nitrogen and promoting nutrient recycling without contributing greatly to greenhouse gas emissions. However, overfishing, hypoxia, and habitat destruction have led to a significant decline in oyster populations. Efforts have been made to restore oyster reefs and develop oyster aquaculture, with the potential for oysters to help offset excess nitrogen loading and improve coastal water quality.
NATURE SUSTAINABILITY
(2021)
Article
Environmental Sciences
E. J. Chamberlain, A. J. Christ, R. W. Fulweiler
Summary: The study of Lake Eggers in Antarctica reveals that the lake is primarily fed by local snowmelt and has experienced alternating periods of ice accumulation and sublimation during the Late Holocene. The research suggests a strong climatic influence on the hydrologic regime shifts shaping ice formation at Lake Eggers.
Editorial Material
Environmental Sciences
Judith A. Rosentreter, Alia N. Al-Haj, Robinson W. Fulweiler, Phillip Williamson
Summary: Coastal wetlands play a crucial role as natural 'blue carbon' sinks, but their function may be compromised by methane and nitrous oxide emissions. The fluxes of these greenhouse gases show high variability, leading to uncertainties in global estimates. Further research is needed to quantify these emissions accurately and to understand the factors contributing to the variability in order to effectively utilize coastal blue carbon ecosystems for climate mitigation.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Soil Science
Hollie E. Emery, John H. Angell, Akaash Tawade, Robinson W. Fulweiler
Summary: Coastal wetlands exhibit different emission patterns of CO2, CH4, and N2O following tidal inundation and rainfall, and accurately predicting carbon and nitrogen cycling in salt marshes requires considering pulse responses and baseline gas flux rates.
SOIL BIOLOGY & BIOCHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Robinson W. Fulweiler, Sarah W. Davies, Jennifer F. Biddle, Amy J. Burgin, Emily H. G. Cooperdock, Torrance C. Hanley, Carly D. Kenkel, Amy M. Marcarelli, Catherine M. Matassa, Talea L. Mayo, Lory Z. Santiago-Vazquez, Nikki Traylor-Knowles, Maren Ziegler
Summary: The inequalities faced by academic mothers, especially during the COVID-19 pandemic, can be addressed through strategic investments and new strategies. These efforts not only benefit mothers disproportionately impacted by the pandemic, but also have broader implications for creating a more equitable society for all.
Article
Environmental Sciences
S. G. Ayvazian, Nicholas E. Ray, Anna Gerber-Williams, Sinead Grabbert, Adam Pimenta, Boze Hancock, Donald Cobb, Charles Strobel, R. W. Fulweiler
Summary: Efforts to quantify biogeochemical and ecological processes in oyster habitats have shown that oysters may impact nitrogen cycling and ecosystem structure, but competition and refuge effects in habitats need further investigation.
ESTUARIES AND COASTS
(2022)
Article
Engineering, Environmental
Nicholas E. Ray, Robinson W. Fulweiler
Summary: In oyster habitats, the sediments show peak carbon dioxide production in spring and summer, as well as consistent methane release into the water column, while nitrous oxide is generally absorbed with occasional release in spring. The overall impact of oysters on sediment greenhouse gas cycling in temperate regions is considered negligible.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Limnology
Emily J. Chua, Robert Timothy Short, Andres M. Cardenas-Valencia, William Savidge, Robinson W. Fulweiler
Summary: Sandy sediments play a key role in global biogeochemical cycles, but we lack understanding of their functionality and response to climate change. The development of a new pore-water sampler, coupled with a portable mass spectrometer, allows for measuring dissolved gases in sandy sediments and has been validated through laboratory experiments. This new approach has the potential to greatly advance our understanding of biogeochemical processes in aquatic systems with sandy sediments.
LIMNOLOGY AND OCEANOGRAPHY-METHODS
(2021)
Letter
Plant Sciences
Mollie R. Yacano, Sarah Q. Foster, Nicholas E. Ray, Autumn Oczkowski, John A. Raven, Robinson W. Fulweiler
Article
Limnology
Amy M. Marcarelli, Robinson W. Fulweiler, J. Thad Scott
Summary: Nitrogen fixation is a crucial element of the global nitrogen cycle, but its rates and ecological dynamics in inland and coastal aquatic ecosystems are still largely unknown. This is due to the diversity of these habitats and the traditional belief that nitrogen fixation rates in these ecosystems are low or non-existent.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2022)
Article
Limnology
Emily J. Chua, Markus Huettel, Katja Fennel, Robinson W. Fulweiler
Summary: The marine nitrogen cycle is a major factor in ocean productivity and global climate, with recent research suggesting that permeable sandy sediments on continental shelves are key components. Despite decades of study, the role of shelf sediments in marine nitrogen cycling remains unclear and controversial, requiring further investigation to address unresolved issues.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2022)
Review
Multidisciplinary Sciences
Rachel E. Mason, Joseph M. Craine, Nina K. Lany, Mathieu Jonard, Scott Ollinger, Peter M. Groffman, Robinson W. Fulweiler, Jay Angerer, Quentin D. Read, Peter B. Reich, Pamela H. Templer, Andrew J. Elmore
Summary: The productivity and life-supporting capacity of ecosystems depend on access to reactive nitrogen. However, long-term records show that nitrogen availability is declining in many regions of the world. Global changes, such as elevated atmospheric carbon dioxide levels and rising temperatures, are affecting the balance between ecosystem nitrogen supply and demand. This decline in nitrogen availability is limiting primary productivity and reducing the quality of herbivore diets in many ecosystems. We outline the current state of knowledge about declining nitrogen availability and propose actions to address this emerging challenge.
Article
Limnology
Alia N. Al-Haj, Tyler Chidsey, Robinson W. Fulweiler
Summary: Seagrasses are important for mitigating climate change, but their actual carbon sequestration capacity also depends on methane and nitrous oxide fluxes. This study observed methane and nitrous oxide fluxes in seagrass meadows and found that the systems were small net sources of these gases to the atmosphere. The sediments were not likely the source of these gases emitted to the atmosphere.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Limnology
Claudia I. Mazur, Robinson W. Fulweiler
Summary: The impact of coastal acidification on sediment N2O and CH4 fluxes is still unclear. This study exposed temperate estuarine sediments to moderate and extreme acidification and found that low pH had a strong effect on greenhouse gas fluxes, but the response varied depending on the site and nitrogen loading. Sediments from high-nitrogen loading site showed increased N2O fluxes and decreased CH4 fluxes under acidification, while sediments from low-nitrogen loading site exhibited decreased N2O fluxes and both decreased and increased CH4 fluxes. This study highlights the dynamic response of sediment N2O and CH4 fluxes to low pH and emphasizes the need for a deeper understanding of coastal acidification impacts on sediment biogeochemistry.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2023)
