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In stream ecosystems, coarse organic matter from the riparian vegetation, a key food resource, is often retained in the floodplains before reaching the channel. During floodplain exposure, organic matter can be affected by abiotic and biotic processes ("preconditioning"), which alter its quality and affect its subsequent decomposition in streams. We analyzed the effect of floodplain preconditioning on wood quality (lignin, C, N, P, K, among others), and its subsequent aquatic breakdown, paying special attention to microbial activity. We simulated preconditioned standard wooden sticks on one arid stream floodplain for 3 and 4 months, and then monitored their breakdown in three different streams, together with control (non-preconditioned) sticks. Preconditioning reduced lignin mass and C:N and lignin:N ratios, caused the leaching of soluble nutrients such as P and K, as well as N immobilization by microbes. These changes enhanced the breakdown of wood in the first week of immersion, but had no effect on breakdown rates after 4 months of incubation in the streams, although N immobilization was diminished. Our results suggest that terrestrial preconditioning could alter the role of wood as a long-lasting nutrients and energy source for freshwater ecosystem.
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http://dx.doi.org/10.1016/j.scitotenv.2015.11.050 | DOI Listing |
Environ Technol
September 2025
College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, People's Republic of China.
The soil in reclaimed shale gas sites is compacted and suffers from issues like poor drainage, drought conditions, and nutrient deficiency, posing challenges for agricultural production. In this study, rare earth tailings were incorporated into biochar at different mass ratios (rare earth tailings: biochar = 1:1, 1:2, 1:3, 1:4). Subsequently, a series of rare earth tailings-doped biochar materials (REE-BC) were prepared by calcination at 700°C.
View Article and Find Full Text PDFSci Adv
September 2025
Department of Environmental Science, Stockholm University, Stockholm, Sweden.
Organic matter stored in Arctic permafrost represents a key component of the carbon cycle, yet its reactivity across heterogeneous continent-scale permafrost regions remains poorly understood. Here, we leverage the four shelf seas of the Eurasian Arctic as integrative receptor systems to evaluate terrestrial organic matter reactivity, assessed by examining organic carbon preservation as a function of C-constrained cross-shelf transport time. Our findings reveal higher reactivity of terrestrial organic matter released to the Laptev Sea and the eastern East Siberian Sea, lower reactivity in the western East Siberian Sea, and no deducible degradation in the Kara Sea.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Frontiers Science Center for New Organic Matter, State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin 300071, PR China.
Antigen-capturing nanomaterials hold great promise for cancer immunotherapy; however, the need for tumor localized administration and limited antigen-binding affinity remains the "Achilles heel" of this strategy. Herein, we present a tumor microenvironment (TME)-activatable nanoplatform, TDR848@FPB, designed for systemic administration and enhanced covalent capture of tumor-associated antigens (TAAs), enabling effective immunotherapy with minimal off-target effects and independent of localized tumor administration. This platform encapsulates a photosensitizer-conjugated, light-activated toll-like receptor (TLR) agonist, which induces immunogenic cell death and triggers a pro-inflammatory TME conducive to antigen capture upon light irradiation.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China.
Low molecular weight amines promote sulfate (SO and HSO) formation through acid-base reactions, contributing to fine particulate matter (PM). Heterogeneous ozonation converts nontoxic amine salts into highly toxic products, yet the ozonation activation mechanism is unclear. This work reveals a sulfate-dominant ozonation mechanism of amine salts in fine PM by combining advanced mass spectrometry and ab initio calculation methods.
View Article and Find Full Text PDFAnim Sci J
September 2025
Department of Zotechnics and Animal Nutrition, Faculty of Veterinary Medicine, Van Yuzuncu Yil University, Van, Turkey.
The aim of this experiment was to determine the effects of walnut (Juglans regia L.) green husk (WGH) supplemented to ration on rumen fermentation by in vitro gas production technique. WGH was supplemented at different ratios (0%, 2%, 4%, 6%, 8%, and 10%) to the total mixture ration formed from 80%/20% roughage/concentrate feed.
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