Organic matter (OM) is an important component of sediment. Bioturbation/bioirrigation can remobilize OM and heavy metals that were previously buried in the sediment. The remobilization of buried organic matter, thallium (Tl), cadmium (Cd), copper (Cu) and zinc (Zn) from sediment was studied in a laboratory experiment with three organisms: tubificid, chironomid larvae and loach. Results showed that bioturbation/bioirrigation promoted the release of dissolved organic matter (DOM) and dissolved Tl, Cd, Cu and Zn, but only dissolved Zn concentrations decreased with exposure time in overlying water. The presence of organisms altered the compositions of DOM released from sediment, considerably increasing the percentage of fulvic acid-like materials (FA) and humic acid-like materials (HA). In addition, bioturbation/bioirrigation accelerated the growth and reproduction of bacteria to enhance the proportion of soluble microbial byproduct-like materials (SMP). The DOM was divided into five regions in the three-dimensional excitation emission matrix (3D-EEM), and each part had different correlation with the dissolved heavy metal concentrations. Dissolved Cu had the best correlation with each of the DOM compositions, indicating that Cu in the sediment was in the organic-bound form. Furthermore, the organism type and heavy metal characteristics both played a role in influencing the remobilization of heavy metal.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jes.2018.03.031 | DOI Listing |
Sci Total Environ
January 2025
China National Environmental Monitoring Centre, Beijing 100012, China.
The riverine dissolved organic matter (DOM) pool constitutes the largest and most dynamic organic carbon reservoir within inland aquatic systems. Human activities significantly alter the distribution of organic matter (OM) in rivers, thereby affecting the availability of DOM. However, the impact of total suspended solids (TSS) on DOM under anthropogenic influence remains insufficiently elucidated.
View Article and Find Full Text PDFSci Total Environ
January 2025
College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address:
The increasing frequency of cyanobacterial blooms, particularly those induced by Microcystis aeruginosa (M. aeruginosa), poses severe economic, ecological and health challenges due to the production of microcystins (MCs). Environmental parameters such as light and nutrient availability influence MCs production, while the role of dissolved organic matter (DOM) photochemical processes in regulating these remains unclear.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Chemistry, Physics, Environmental and Soil Sciences, University of Lleida - AGROTECNIO-CERCA Center, Rovira Roure 191, 25198 Lleida, Spain.
There is limited research on the influence of environmental variables on the interactions of biodegradable microplastics with chromium. This study reports the results of adsorption experiments with Cr and poly(lactic acid) (PLA) in synthetic aqueous solutions. It addresses the influence of the initial oxidation state, Cr(III) or Cr(VI), the effects of UV irradiation and the presence of organic matter.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling 712100, China. Electronic address:
The interactions between microplastic-derived dissolved organic matter (MPs-DOM) and heavy metals (Cu, Pb, and Cd) regulate the complex environmental transport behavior of pollutants in terrestrial and aquatic environments. In this study, fluorescence excited emission matrix spectroscopy combined with parallel factor analysis (EEM-PARAFAC) and electrospray ionization coupled Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) were employed to investigate the complexation mechanism of MPs-DOM with heavy metals, as well as the effects of different environmental occurrences of MPs-DOM on the transport behaviors of heavy metals in saturated porous medium. The findings demonstrated that MPs-DOM, particularly humic-like substances containing aromatic structures and various oxygen functional groups, could form stable complexes with heavy metals.
View Article and Find Full Text PDFSmall
January 2025
Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, 28049, Spain.
Conductive metal-organic frameworks (MOFs) are crystalline, intrinsically porous materials that combine remarkable electrical conductivity with exceptional structural and chemical versatility. This rare combination makes these materials highly suitable for a wide range of energy-related applications. However, the electrical conductivity in MOF-based devices is often limited by the presence of different types of structural disorder.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!