To address the complex biogeochemical processes and potential function of dissolved organic matter (DOM) in estuaries before it enters the sea, water samples were collected seasonally in a dozen Laizhou Bay estuaries and in the Yellow River estuary, North China. The results showed that chromophoric dissolved organic matter (CDOM) varied in abundance but had consistent spectral slopes at the same sampling time. Gradually, CDOM decreased while spectral slopes increased from freshwater to seawater. The spectral slope of CDOM varied temporally (higher in October and lower in August) more than it varied spatially. The fluorescent components and biological indices of CDOM indicated that in situ biological activities were the dominant sources in the waters examined in this study. The CDOM was generally more variable than the dissolved organic carbon (DOC) in most of the estuaries. However, marine CDOM may obviously increase in estuaries when indirectly stimulated by rapidly decomposing terrestrial DOM.
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http://dx.doi.org/10.1016/j.marenvres.2023.106102 | DOI Listing |
J Environ Manage
January 2025
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom.
Tree-planting is increasingly presented as a cost-effective strategy to maximise ecosystem carbon (C) storage and thus mitigate climate change. Its success largely depends on the associated response of soil C stocks, where most terrestrial C is stored. Yet, we lack a precise understanding of how soil C stocks develop following tree planting, and particularly how it affects the form in which soil C is stored and its associated stability and resistance to climate change.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir, Chongqing Three Georges University, Chongqing, 404100, PR China.
Nitrogen and phosphorus depositions and global warming have continuously intensified, impacting soil respiration. However, the response mechanisms of soil respiration rate (R) and its temperature sensitivity (Q) to nitrogen and phosphorus depositions are still unclear, especially for riparian zones. Intact Fluvisols were collected at different water-level elevations (150, 160, 170, and 180 m) of the riparian zone of the Three Gorges Reservoir, China and incubated under 20 and 30 °C with additions of nitrogen (36 kg N ha yr), phosphorus (0.
View Article and Find Full Text PDFChemosphere
January 2025
Department of Civil and Environmental Engineering, Institute of Science Tokyo, Meguro-ku, Tokyo, 152-8552, Japan. Electronic address:
Anaerobic digestion (AD) offers great potential for pollutant removal and bioenergy recovery. However, it faces challenges when using livestock manure (LSM) as a feedstock given its high content of refractory materials (e.g.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo 315211, China.
Viruses are considered to regulate bacterial communities and terrestrial nutrient cycling, yet their effects on bacterial metabolism and the mechanisms of carbon (C) dynamics during dissolved organic matter (DOM) mineralization remain unknown. Here, we added active and inactive bacteriophages (phages) to soil DOM with original bacterial communities and incubated them at 18 or 23 °C for 35 days. Phages initially (1-4 days) reduced CO efflux rate by 13-21% at 18 °C and 3-30% at 23 °C but significantly ( < 0.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Aquatic Ecology, Netherlands Institute of Ecology, Wageningen 6708 PB, The Netherlands.
Arctic ecosystems are affected by accelerated warming as well as the intensification of the hydrologic cycle, yet understanding of the impacts of compound climate extremes (e.g., simultaneous extreme heat and rainfall) remains limited, despite their high potential to alter ecosystems.
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