A5087030683- Pleistocene-Era Hominins and Archaeology
- Geology and Paleoclimatology Research
- Evolution and Paleontology Studies
- Primate Behavior and Ecology
- Isotope Analysis in Ecology
- Atmospheric and Environmental Gas Dynamics
- Karst Systems and Hydrogeology
- Forensic Anthropology and Bioarchaeology Studies
- Ocean Acidification Effects and Responses
- Archaeology and ancient environmental studies
- Groundwater and Isotope Geochemistry
- Wildlife Ecology and Conservation
- Marine and environmental studies
- Soil Carbon and Nitrogen Dynamics
- Methane Hydrates and Related Phenomena
- Fire effects on ecosystems
- Maritime and Coastal Archaeology
- Bat Biology and Ecology Studies
- Geological and Geophysical Studies Worldwide
- Hydrocarbon exploration and reservoir analysis
- Climate change and permafrost
- Marine and coastal ecosystems
- Arctic and Antarctic ice dynamics
- Pacific and Southeast Asian Studies
- Soil and Water Nutrient Dynamics
U.S. National Science Foundation
2016-2025
University of South Florida
2011-2024
Carnegie Institution for Science
2021
Babeș-Bolyai University
2016
Division of Earth Sciences
2016
University of St Andrews
2004-2008
Australian National University
2002-2006
United States Geological Survey
2005
University of Oregon
2000-2003
GTx (United States)
2003
Pyrogenic carbon (PyC; includes soot, char, black carbon, and biochar) is produced by the incomplete combustion of organic matter accompanying biomass burning fossil fuel consumption. PyC pervasive in environment, distributed throughout atmosphere as well soils, sediments, water both marine terrestrial environment. The physicochemical characteristics are complex highly variable, dependent on precursor conditions formation. A component recalcitrant persists environment for millennia. However,...
Carbon isotope studies of early hominins from southern Africa showed that their diets differed markedly the extant apes. Only recently, however, has a major influx isotopic data eastern allowed for broad taxonomic, temporal, and regional comparisons among hominins. Before 4 Ma, had were dominated by C 3 resources were, in sense, similar to chimpanzees. By about 3.5 multiple hominin taxa began incorporating 13 C-enriched [C or crassulacean acid metabolism (CAM)] foods highly variable carbon...
Abstract New stable carbon isotope measurements, coupled with paleoprecipitation estimates, both from Plio‐Pleistocene paleosols of the Turkana Basin, Kenya, provide a high‐resolution record aridification and increasing C 4 biomass during past 4.3 Ma. This trend is marked by several punctuations at 3.58–3.35, 2.52–2, 1.81–1.58 Ma, which running mean variance δ 13 paleoaridity estimates increase, suggesting that proportion increases in savanna mosaics periods heightened aridity. Increase...
Abstract The large difference in the degree of discrimination stable carbon isotopes between C3 and C4 plants is widely exploited global change cycle research, often with assumption that retains isotopic signature its photosynthetic pathway during later stages decomposition soil sediments. We applied long‐term incubation experiments natural 13 C‐labelling C4‐derived organic (SOC) collected from across major environmental gradients Australia to elucidate a significant rate C3‐ SOC. find...
We present data on soil organic carbon (SOC) inventory for 7050 cores collected from a wide range of environmental conditions throughout Australia. The set is stratified over the spatial distribution trees and grass to account variability SOC with vegetation distribution. model controls using an index water availability mean annual temperature represent climatic control rate C input into pool decomposition SOC, in addition fraction particles <63 μm diameter as measure textural...
Abstract Among abundant reconstructions of Holocene climate in Europe, only a handful has addressed winter conditions, and most these are restricted length and/or resolution. Here we present record late autumn through early air temperature moisture source changes East-Central Europe for the Holocene, based on stable isotopic analysis an ice core recovered from cave Romanian Carpathian Mountains. During past 10,000 years, reconstructed followed insolation, with minimum by gradual continuous...
Abstract. The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest controversy among paleoanthropologists for decades. Prior attempts to understand side this equation centered around study outcrop sediments fossils adjacent where fossil hominins (ancestors or close relatives modern humans) are found, from deep sea drill cores. However, often highly weathered thus unsuitable some types paleoclimatic records,...
The enhanced dietary flexibility of early hominins to include consumption C 4 /crassulacean acid metabolism (CAM) foods (i.e., derived from grasses, sedges, and succulents common in tropical savannas deserts) likely represents a significant ecological behavioral distinction both extant great apes the last ancestor that we shared with apes. Here, use stable carbon isotopic data 20 samples Australopithecus afarensis Hadar Dikika, Ethiopia (>3.4–2.9 Ma) show this species consumed diet /CAM...
[1] Recently, a series of studies have targeted the stable isotopic composition cave ice as possible source paleoclimatic information, but none presented an explanation for way in which external climatic signal is transferred to ice. While relation between precipitation and drip water can be relatively easily determined, more complex problem arises, i.e., alteration primary recorded by oxygen hydrogen isotopes during freezing form Here we report results first detailed investigations isotope...
Abstract. Widespread burning of mixed tree–grass ecosystems represents the major natural locus pyrogenic carbon (PyC) production. PyC is a significant, pervasive and yet poorly understood "slow-cycling" form present in atmosphere, hydrosphere, soils sediments. We conducted 16 experimental burns on rainfall transect through northern Australian savannas with C4 grasses ranging from 35 to 99% total biomass. Residues each fire were partitioned into further recalcitrant (HyPyC) components, these...
Abstract Despite recent evidence suggesting that groundwater inputs of dissolved inorganic carbon (DIC) to rivers can contribute substantially the fluvial evasion dioxide (CO 2 ), is seldom integrated into budgets. Also, unclear way equilibria between CO and ionic forms carbonate will affect from rivers. We conducted longitudinal river surveys radon along two tropical Australia developed a mass balance framework assess influence groundwater‐derived buffering on rates. The mean flux totaled...