A5038788861- Peatlands and Wetlands Ecology
- Mercury impact and mitigation studies
- Mine drainage and remediation techniques
- Microbial Community Ecology and Physiology
- Coastal wetland ecosystem dynamics
- Methane Hydrates and Related Phenomena
- Heavy metals in environment
- Atmospheric and Environmental Gas Dynamics
- Groundwater and Isotope Geochemistry
- Soil and Water Nutrient Dynamics
- Climate change and permafrost
- Atmospheric chemistry and aerosols
- Heavy Metal Exposure and Toxicity
- Geochemistry and Geologic Mapping
- Marine and coastal ecosystems
- Toxic Organic Pollutants Impact
- Water Treatment and Disinfection
- Geochemistry and Elemental Analysis
- Microbial Fuel Cells and Bioremediation
- Hydrocarbon exploration and reservoir analysis
- Wastewater Treatment and Nitrogen Removal
- Marine Biology and Ecology Research
- Geology and Paleoclimatology Research
- Odor and Emission Control Technologies
- Anaerobic Digestion and Biogas Production
University of Massachusetts Lowell
2012-2021
Exponent (United States)
2009
Syracuse University
2009
Upstate Freshwater Institute
2009
University of Hawaiʻi at Mānoa
2008
University of Alaska Anchorage
1997-2004
United States Geological Survey
2004
University of Castilla-La Mancha
2004
Providence College
2004
University of New Hampshire
1990-1999
Speciation of Hg and conversion to methyl-Hg were evaluated in mine wastes, sediments, water collected from the Almadén District, Spain, world's largest producing region. Our data for methyl-Hg, a neurotoxin hazardous humans, are first reported sediment area. Concentrations waste, sediment, among highest found at mines worldwide. Mine wastes contain highly elevated concentrations, ranging 160 34 000 μg/g, varies <0.20 3100 ng/g. Isotopic tracer methods indicate that one site (Almadenejos)...
Sulfate reduction rates, dissolved iron and sulfide concentrations, titration alkalinity were measured in salt marsh soils along a transect that included areas inhabited by both the tall short forms of Spartina alterniflora patens. Pore waters collected with situ “sippers” to acquire temporal data from same location without disturbing plant roots. During 1984, at weekly intervals showed rapid changes belowground biogeochemical processes coincided S. physiology. Rates SO 4 2 increased...
We found a consistent distribution pattern for radiocarbon in dissolved organic carbon (DOC), inorganic (DIC), and methane replicated across spatial temporal scales northern peatlands from Minnesota to Alaska. The 14 C content of DOC is relatively modern throughout the peat column, depths 3 m. In sedge‐dominated peatlands, contents products respiration, CH 4 DIC, are essentially same similar that DOC. Sphagnum ‐ woody plant–dominated with few sedges, however, respiration but intermediate...
ABSTRACT Methylmercury (MeHg), a neurotoxic substance that accumulates in aquatic food chains and poses risk to human health, is synthesized by anaerobic microorganisms the environment. To date, mercury (Hg) methylation has been attributed sulfate- iron-reducing bacteria (SRB IRB, respectively). Here we report methanogen, Methanospirillum hungatei JF-1, methylated Hg sulfide-free medium at comparable rates, but with higher yields, than those observed for some SRB IRB. Phylogenetic analyses...
Microbial fuel cells (MFCs) offer the potential for generating electricity, mitigating greenhouse gas emissions, and bioremediating pollutants through utilization of a plentiful renewable resource: soil organic carbon. We analyzed bacterial community structure, MFC performance, characteristics in different microhabitats within MFCs constructed from agricultural or forest soils order to determine how type dynamics influence performance. Our results indicated that had power output about 17...
The population composition and biogeochemistry of sulfate-reducing bacteria (SRB) in the rhizosphere marsh grass Spartina alterniflora was investigated over two growing seasons by molecular probing, enumerations culturable SRB, measurements SO42- reduction rates geochemical parameters. rapid sediments with up to 3.5 &mgr;mol ml-1 day-1. Rates increased greatly when plant growth began April decreased again plants flowered late July. Results nucleic acid probes revealed that SRB rRNA accounted...
Field measurements and incubation techniques were used to determine the dynamics of acetate formation, iron reduction, methanogenesis in surficial peat an Alaskan bog. Acetate concentrations ∼100 μ M early season decreased ∼20 July when water table decreased. levels increased rapidly ∼1000 rose surface August. production anaerobic slurries occurred at rates 2.8–420 nmol carbon mL −1 day , which was 7–120 times more rapid than CH 4 production. Experiments utilizing 14 C‐acetate confirmed that...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInteractions of .alpha.-lactalbumin and bovine serum albumin with .beta.-lactoglobulin in thermally induced gelationMark E. Hines Allen. FoegedingCite this: J. Agric. Food Chem. 1993, 41, 3, 341–346Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://doi.org/10.1021/jf00027a001Request reuse permissionsArticle Views762Altmetric-Citations120LEARN ABOUT THESE METRICSArticle Views are...
Laboratory incubations, gas and solute analyses, stable isotope methods were used to investigate the pathway of methanogenesis in 25 wetland peats varying vegetation composition along a latitudinal gradient Alaska. Sites divided into gross classes indicative tropic status: mostly Sphagnum (class 1); plus vascular plants (i.e., Carex ) 2); plants, but still containing 3), and; sites dominated by with no visible species 4). The magnitude CO 2 , acetate CH 4 as end products anaerobic metabolism...
Although northern peatlands contribute significantly to natural methane emissions, recent studies of the importance and type methanogenesis in these systems have provided conflicting results. Mechanisms controlling remain poorly understood, despite as a greenhouse gas. We used 16S rRNA gene retrieval denaturing gradient gel electrophoresis (DGGE) analyse archaeal communities 15 high-latitude peatland sites Alaska three mid-latitude Massachusetts. Archaeal community composition was analysed...
Phylogenetic diversity and community composition of sulfate-reducing bacteria in a salt marsh sediment the rhizosphere Spartina alterniflora were investigated. Uncultivated Desulfobacteriaceae family-related phylotypes studied by selectively amplifying 16S rRNA gene fragments from DNA extracted samples. Two novel retrieved samples, with A01 having 89.1% sequence similarity Desulfococcus multivorans 4D19 96.3% Desulfosarcina variabilis. Additionally, six sequences that extremely closely...
Microbial Fe reduction in acetate- and succinate-containing enrichment cultures initiated with an estuarine sediment inoculum was studied. unaffected when SO 4 2− inhibited by MoO , indicating that both processes could occur independently. Bacterially produced sulfide precipitated as FeS but not completely responsible for reduction. The separation of oxidized particles from bacteria dialysis tubing demonstrated direct bacterial contact necessary amended NO 3 − delayed until 2 were removed....
Research Article| October 01, 1984 Calcification of cyanobacterial mats in Solar Lake, Sinai W. Berry Lyons; Lyons 1Department Earth Sciences and Ocean Process Analysis Laboratory, University New Hampshire, Durham, Hampshire 03824 Search for other works by this author on: GSW Google Scholar David T. Long; Long 2Department Geological Sciences, Michigan State University, East Lansing, 48824 Mark E. Hines; Hines 3Department Jackson Estuarine Henri Gaudette; Gaudette 4Department Peter B....
The accumulation of monomethyl mercury (CH3Hg+) in aquatic ecosystems is a redox sensitive process that accelerated under sulfate-reducing conditions. While nitrate (NO3−) reduction energetically favored over sulfate reduction, the influence NO3− on CH3Hg+ has not been reported literature. We examined temporal and vertical patterns constituents concentrations hypolimnion dimictic lake, Onondaga Lake, prior to following increases inputs. Detailed water-column profiles long-term record...
Peat bogs dominated by Sphagnum spp. have relatively high areal rates of dimethyl sulfide (DMS) emission to the atmosphere. DMS was produced in anoxic slurries peat with a linear time course and an average rate 40.4 (range, 22.0 68.6) nmol per liter slurry (middot) day(sup-1) observed nine batches slurry. Methanethiol (MeSH) at roughly similar over typical 4- 8-day incubations. MeSH production these acidic (pH 4.2 4.6) peats were biological, as they stopped completely autoclaving inhibited...
High latitude wetlands are significant sources of atmospheric methane, with emission rates that susceptible to effects climate change. Our data demonstrate unlike mid‐latitude wetlands, methane in northern peatlands is not derived from acetate or C 1 compounds. These latter compounds accumulate high levels as the primary organic end product anaerobic decomposition. Acetate ultimately degraded aerobically carbon dioxide after diffusion into oxic regions peat. Therefore, precursors destined...