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Permafrost thaw in Arctic watersheds threatens to mobilize hitherto sequestered carbon. We examine the radiocarbon activity (FC) of dissolved organic carbon (DOC) in the northern Mackenzie River basin. From 2003-2017, DOC-FC signatures (1.00 ± 0.04; = 39) tracked atmospheric CO, indicating export of "modern" carbon. This trend was interrupted in June 2018 by the widespread release of aged DOC (0.85 ± 0.16, = 28) measured across three separate catchment areas. Increased nitrate concentrations in June 2018 lead us to attribute this pulse of C-depleted DOC to mobilization of previously frozen soil organic matter. We propose export through lateral perennial thaw zones that occurred at the base of the active layer weakened by preceding warm summer and winter seasons. Although we are not yet able to ascertain the broader significance of this "anomalous" mobilization event, it highlights the potential for rapid and large-scale release of aged carbon from permafrost.
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http://dx.doi.org/10.1029/2020GL088823 | DOI Listing |
Integr Environ Assess Manag
September 2025
Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa.
Pesticides are widely used to meet the food demands of a growing population, with various types used to control pests depending on the crops grown. Rainfall, overspray, and runoff from agricultural fields can wash these insecticides into water bodies, posing documented environmental risks. Imidacloprid is commonly used in Afrotropical regions such as South Africa, yet limited information is available on its toxicity to aquatic ecosystems within this climate region.
View Article and Find Full Text PDFEnviron Toxicol Chem
September 2025
Statistical Ecotoxicology, University of Bayreuth, Bayreuth, Germany.
Several micro- and nanoplastic particle (MNP) traits, like polymer type, size, and shape, have been shown to influence MNP toxicity. However, the direction and strength of these moderating effects are often unclear, and generalizations from single studies are challenging to establish. Meta-analyses increase generalizability and derive more accurate and precise effect size estimates by combining measurements from published studies.
View Article and Find Full Text PDFFront Plant Sci
August 2025
Department Soil Science and Environmental Analyses, Institute of Soil Science and Plant Cultivation-State Research Institute, Puławy, Poland.
Introduction: Soil dissolved organic matter (DOM) regulates nutrient cycling and carbon sequestration, yet how cropping systems (rotation vs. monoculture) shape the vertical distribution and molecular traits of DOM remains unclear.
Methods: We leveraged a long-term experiment (est.
Water Res
August 2025
State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Phosphorus is recognized as a major pollutant in municipal and domestic wastewater, but the effective removal of organic phosphorus (OP) using conventional wastewater treatment technologies is difficult. Herein, a novel visible light-enhanced Ti electrocoagulation (EC) technology was proposed for the removal of OP using 2-amino-ethyl phosphonic acid (AEP) as a model compound to elucidate the removal efficiency and mechanisms. The results showed that the irradiation under visible light (670 Lux) effectively enhanced the removal of AEP by Ti EC.
View Article and Find Full Text PDFPestic Biochem Physiol
November 2025
National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Key Laboratory of Agricultural Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, 61 Daizong Road, Tai'an 271018, PR China. Electronic address: wj
Difenoconazole (DFC) is a commonly used triazole fungicide known for its high efficiency and environmental persistence. A thorough understanding of its environmental behavior, particularly sorption in soil, is critical to obtain a comprehensive assessment of the ecological risk of DFC. In this study, three soils with distinct physicochemical properties (brown soil, cinnamon soil, and fluvo-aquic soil) were used to elucidate the adsorption mechanisms of DFC on soil.
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