A5006131662- Toxic Organic Pollutants Impact
- Geology and Paleoclimatology Research
- Marine and coastal ecosystems
- Atmospheric and Environmental Gas Dynamics
- Isotope Analysis in Ecology
- Coastal wetland ecosystem dynamics
- Methane Hydrates and Related Phenomena
- Atmospheric chemistry and aerosols
- Archaeology and ancient environmental studies
- Microbial Community Ecology and Physiology
- Archaeology and Historical Studies
- Pharmaceutical and Antibiotic Environmental Impacts
- Hydrocarbon exploration and reservoir analysis
- Environmental Toxicology and Ecotoxicology
- Coastal and Marine Dynamics
- Effects and risks of endocrine disrupting chemicals
- Analytical chemistry methods development
- Crime, Illicit Activities, and Governance
- Corruption and Economic Development
- Oil Spill Detection and Mitigation
- ICT Impact and Policies
- Geological formations and processes
- Groundwater flow and contamination studies
- Heavy metals in environment
- Tropical and Extratropical Cyclones Research
East Carolina University
2014-2025
William & Mary
1997-2023
Bharat Petroleum (India)
2021
Jadavpur University
2020
North Carolina State University
2019
Institute of Geological Sciences
2017
Mitchell Institute
2013
Binghamton University
2003-2012
Cary Institute of Ecosystem Studies
2010
CUTS International
2009
Black carbon (BC), the product of incomplete combustion fossil fuels and biomass (called elemental (EC) in atmospheric sciences), was quantified 12 different materials by 17 laboratories from disciplines, using seven methods. The were divided into three classes: (1) potentially interfering materials, (2) laboratory‐produced BC‐rich (3) BC‐containing environmental matrices (from soil, water, sediment, atmosphere). This is first comprehensive intercomparison this type (multimethod, multilab,...
The Younger Dryas boundary (YDB) cosmic-impact hypothesis is based on considerable evidence that Earth collided with fragments of a disintegrating ≥100-km-diameter comet, the remnants which persist within inner solar system ∼12,800 y later. Evidence suggests YDB cosmic impact triggered an "impact winter" and subsequent (YD) climate episode, biomass burning, late Pleistocene megafaunal extinctions, human cultural shifts population declines. deposited anomalously high concentrations platinum...
Part 1 of this study investigated evidence biomass burning in global ice records, and here we continue to test the hypothesis that an impact event at Younger Dryas boundary (YDB) caused anomalously intense episode ∼12.8 ka on a multicontinental scale (North South America, Europe, Asia). Quantitative analyses charcoal soot records from 152 lakes, marine cores, terrestrial sequences reveal major peak (YD) onset appears be highest during latest Quaternary. For Cretaceous-Tertiary (K-Pg) event,...
Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have found influence its cycling longevity in the environment. Dissolution via leaching may main control on loss processes such as microbial or abiotic oxidation, mineral sorption, export aquatic systems. Yet, little is known controls dissolved organic matter (pyDOM) generation composition. Here, yield composition pyDOM generated through batch a thermal series oak...
Abstract Pyrogenic dissolved organic matter (pyDOM) is known to be an important biogeochemical constituent of aquatic ecosystems and the carbon cycle. While recent studies have examined how pyDOM production, composition, photolability varies with parent pyrogenic solid material type, we lack understanding potential microbial mineralization transformation in biogeosphere. Thus, leachates oak, charred at 400 °C 650 °C, as well their photodegraded counterparts were incubated a soil‐extracted...
Black carbon (BC) may be a major component of riverine exported to the ocean, but its flux from large rivers is unknown. Furthermore, global distribution BC between natural and anthropogenic sources remains uncertain. We have determined concentrations in suspended sediments Mississippi River, 7th largest river world terms sediment water discharge, during high flow low 1999. The 1999 annual River was 5 × 10-4 petagrams (1 Pg = 1015 g 1 gigaton). also applied principal components analysis...
Lumbriculus variegatus and Diporeia spp. were exposed to two contaminant pairs 3H-benzo[a]pyrene (BaP) 14C-2,4,5,2'4',5'-hexachlorobiphenyl (HCBP), 3H-pyrene (PY) 14C-3,4,3',4'-tetrachlorobiphenyl (TCBP) sorbed each of seven field-collected sediments varying composition. Toxicokinetic coefficients, bioaccumulation factors (BAF), biota-sediment accumulation ([BSAF], BAF normalized the organism lipid content sediment organic carbon content) determined. The desorption rates from measured with a...
Our understanding of the cycling fire-derived, i.e. pyrogenic organic matter (pyOM), as well goals community researchers who study it, may be inhibited by many terms and methods currently used in its quantification characterization. Terms for pyOM have evolved convention, but are often poorly defined. Further, each different now to quantify solid dissolved carbon (pyC) comes with own biases artifacts. That is, detects only a fraction total products produced fire, while, at same time, include...
We present evidence that in ~ 1650 BCE (~ 3600 years ago), a cosmic airburst destroyed Tall el-Hammam, Middle-Bronze-Age city the southern Jordan Valley northeast of Dead Sea. The proposed was larger than 1908 explosion over Tunguska, Russia, where 50-m-wide bolide detonated with 1000× more energy Hiroshima atomic bomb. A city-wide 1.5-m-thick carbon-and-ash-rich destruction layer contains peak concentrations shocked quartz 5-10 GPa); melted pottery and mudbricks; diamond-like carbon; soot;...
Measures of desorption are currently considered important as potential surrogates for bioaccumulation measures the bioavailability sediment-sorbed contaminants. This study determined rates four laboratory spiked compounds, benzo[a]pyrene (BaP), 2,4,5,2',4',5'-hexachlorobiphenyl (HCBP), 3,4,3',4'-tetrachlorobiphenyl (TCBP), and pyrene (PY), to evaluate effect sediment characteristics. The compounds were sorbed onto seven sediments with a broad range Desorption was measured by Tenax-TA...
Biota-sediment accumulation factors (BSAF) were calculated for Diporeia spp. and oligochaete worms exposed to polychlorinated biphenyls (PCBs) polycyclic aromatic hydrocarbons (PAHs) from field-collected sediment. These data compared the contaminant fraction extracted sediment with Tenax resin using a 24 h extraction. A previous laboratory study suggested linear relationship between log BSAF rapidly desorbed However, in our did not fit this relationship. Better predictive regressions both...
Mesozooplankton (>200 μ m) collected in August and September of 2010 from the northern Gulf Mexico show evidence exposure to polycyclic aromatic hydrocarbons (PAHs). Multivariate statistical analysis revealed that distributions PAHs extracted mesozooplankton were related oil released ruptured British Petroleum Macondo‐1 (M‐1) well associated with R/V Deepwater Horizon blowout. contained 0.03–97.9 ng g −1 total ratios fluoranthene + pyrene less than 0.44, indicating a liquid fossil fuel...
Abstract. With the increased occurrence of wildfires around world, interest in chemistry pyrogenic organic matter (pyOM) and its fate environment has increased. Upon leaching from soils by rain events, significant amounts dissolved pyOM (pyDOM) enter aquatic interact with microbial communities that are essential for cycling within different biogeochemical cycles. To evaluate biodegradability pyDOM, aqueous extracts laboratory-produced biochars were incubated soil microbes, molecular changes...
Abstract Black carbon is ubiquitous in the marine environment. However, whether it accumulates deepest ocean region, hadal zone, unknown. Here we measure concentration and isotopes (δ 13 C Δ 14 C) of black total organic sediments from six trenches. constituted 10% trench carbon, its δ were more negative than those suggesting that was predominantly derived terrestrial C3 plants fossil fuels. The contribution to pool spatially heterogeneous, which could be related differences distance...