Publications by authors named "Leslie L Baker"

Recognizing controlling factors of groundwater chemistry in the ophiolite region of the southeastern area of Kermanshah is the aim of this study. The findings reveal that some samples' calcium, magnesium, and sodium absorption risk is higher than the standard range. Besides, statistical relationships of the data were investigated to recognize the key factors controlling water chemistry.

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The ancient rock record for Mars has long been at odds with climate modelling. The presence of valley networks, dendritic channels and deltas on ancient terrains points towards running water and fluvial erosion on early Mars, but climate modelling indicates that long-term warm conditions were not sustainable. Widespread phyllosilicates and other aqueous minerals on the Martian surface provide additional evidence that an early wet Martian climate resulted in surface weathering.

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In confined animal feeding operations, such as dairies, manure is amended to soils at high rates leading to increases in P and organic matter in the soils. Phosphorus reacts with soil-Ca to form Ca-P minerals, which controls P availability for leaching and transport through the watershed. In this research, the effects of manure sourced dissolved organic matter (DOM) on P sorption on calcite were measured at different reaction times and concentrations.

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Biochar is a renewable energy byproduct that shows promise for remediating contaminated mine sites. A common contaminant at mine sites is arsenic (As). In this study, the effects of biochar amendments to a mine-contaminated soil on As concentrations in mountain brome ( Nees ex Steud.

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Over a century of mining activities in the Coeur d'Alene mining district in Idaho have contaminated soils of the downstream basin with lead, arsenic, zinc, and cadmium. Elevated soil-Pb levels are a significant hazard to the health of humans and wildlife in the region. One in situ treatment approach for remediating Pb-contaminated soils is application of phosphorus to promote the formation of lead phosphate minerals that have low solubility.

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Lead (Pb) is frequently present in urban soils at concentrations of concern for human health. Regulations for this metal are based on total soil concentrations as determined by acid digestion, but a less expensive screening test for Pb would be useful in facilitating more thorough soil testing of urban areas if it could be shown to correlate strongly to total soil Pb. In this study, three extractants (0.

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Charcoal is well known to accumulate contaminants, but its association with metals and other toxic elements in natural settings has not been well studied. Association of contaminants with charcoal in soil and sediment may affect their mobility, bioavailability, and fate in the environment. In this paper, natural wildfire charcoal samples collected from a wetland site that has been heavily contaminated by mine waste were analyzed for elemental contents and compared to the surrounding soil.

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Bioavailability of Cu in the soil is a function of its speciation. In this paper we investigated Cu speciation in six soils using X-ray absorption near edge structure (XANES), extended X-ray absorption fine structure (EXAFS), and synchrotron-based micro X-ray fluorescence (mu-XRF). The XANES and EXAFS spectra in all of the soils were the same.

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Contamination of agricultural soils with Cu as a result of fungicide application and spills threatens environmental quality and reduces soil quality for crop growth. In this paper advanced spectroscopic and microscopic methods were used to elucidate the Cu speciation in a calcareous soil contaminated since the 1940s. Microscopically focused synchrotron-based XRF (micro-SXRF) was used to map the elemental distribution in the soils.

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