A Bayesian framework to unravel food, groundwater, and climate linkages: A case study from Louisiana.

Advancing our understanding of the connections among groundwater, food, and climate is critical to meet global food demands while optimizing water resources usage. However, our understanding of the linkages among groundwater, food, and climate is still limited. Here, we offer a Bayesian framework to simulate crop yield at a regional scale and quantify its relationships and associated uncertainty with climate, groundwater, agricultural, and energy-related variables.

A Granger causality analysis of groundwater patterns over a half-century.

Groundwater depletion in many areas of the world has been broadly attributed to irrigation. However, more formal, data-driven, causal mechanisms of long-term groundwater patterns have not been assessed. Here, we conducted the first Granger causality analysis to identify the "causes" of groundwater patterns using the rice-producing parishes of Louisiana, USA, as an example.

Zinc isotopic signatures in eight lake sediment cores from across the United States.

Zinc is an important trace element pollutant in urban environments; however, the extent of Zn contamination and the sources of urban Zn pollution are often unclear. We measured Zn concentrations and isotopes in sediment cores collected from eight lakes or reservoirs across the United States. We paired these data with historical records of land use within each watershed to calculate a mean Zn concentration and δ(66)Zn for natural (less than 5% urban land use; 123 ± 21.

Zinc isotope investigation of surface and pore waters in a mountain watershed impacted by acid rock drainage.

The pollution of natural waters with metals derived from the oxidation of sulfide minerals like pyrite is a global environmental problem. However, the metal loading pathways and transport mechanisms associated with acid rock drainage reactions are often difficult to characterize using bulk chemical data alone. In this study, we evaluated the use of zinc (Zn) isotopes to complement traditional geochemical tools in the investigation of contaminated waters at the former Waldorf mining site in the Rocky Mountains, Colorado, U.

Copper isotope fractionation during surface adsorption and intracellular incorporation by bacteria.

Copper isotopes may prove to be a useful tool for investigating bacteria-metal interactions recorded in natural waters, soils, and rocks. However, experimental data which attempt to constrain Cu isotope fractionation in biologic systems are limited and unclear. In this study, we utilized Cu isotopes (δ(65)Cu) to investigate Cu-bacteria interactions, including surface adsorption and intracellular incorporation.

Zinc isotopic composition of particulate matter generated during the combustion of coal and coal + tire-derived fuels.

Atmospheric Zn emissions from the burning of coal and tire-derived fuel (TDF) for power generation can be considerable. In an effort to lay the foundation for tracking these contributions, we evaluated the Zn isotopes of coal, a mixture of 95 wt % coal + 5 wt % TDF, and the particulate matter (PM) derived from their combustion in a power-generating plant. The average Zn concentrations and δ(66)Zn were 36 mg/kg and 183 mg/kg and +0.

Zn and Cu isotopes as tracers of anthropogenic contamination in a sediment core from an urban lake.

In this work, we use stable Zn and Cu isotopes to identify the sources and timing of the deposition of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core predates settlement in the region, while the upper sections record the effects of atmospheric emissions from a nearby smelter and rapid urbanization of the watershed. delta(66)Zn and delta(65)Cu varied by 0.

Cd and proton adsorption onto bacterial consortia grown from industrial wastes and contaminated geologic settings.

To model the effects of bacterial metal adsorption in contaminated environments, results from metal adsorption experiments involving individual pure stains of bacteria must be extrapolated to systems in which potentially dozens of bacterial species are present. This extrapolation may be made easier because bacterial consortia from natural environments appear to exhibit similar metal binding properties. However, bacteria that thrive in highly perturbed contaminated environments may exhibit significantly different adsorptive behavior.