Molecular and Dual-Isotopic Profiling of the Microbial Controls on Nitrogen Leaching in Agricultural Soils under Managed Aquifer Recharge.

Nitrate (NO) leaching is a serious health and ecological concern in global agroecosystems, particularly those under the application of agricultural-managed aquifer recharge (Ag-MAR); however, there is an absence of information on microbial controls affecting NO leaching outcomes. We combine natural dual isotopes of NO (N/N and O/O) with metagenomics, quantitative polymerase chain reaction (PCR), and a threshold indicator taxa analysis (TITAN) to investigate the activities, taxon profiles, and environmental controls of soil microbiome associated with NO leaching at different depths from Californian vineyards under Ag-MAR application. The isotopic signatures demonstrated a significant priming effect ( < 0.

Nitrogen fate during agricultural managed aquifer recharge: Linking plant response, hydrologic, and geochemical processes.

Agricultural managed aquifer recharge (Ag-MAR, on-farm recharge), where farmland is flooded with excess surface water to intentionally recharge groundwater, has received increasing attention by policy makers and researchers in recent years. However, there remain concerns about the potential for Ag-MAR to exacerbate nitrate (NO) contamination of groundwater, and additional risks, such as greenhouse gas emissions and crop tolerance to prolonged flooding. Here, we conducted a large-scale, replicated winter groundwater recharge experiment to quantify the effect of Ag-MAR on soil N biogeochemical transformations, potential NO leaching to groundwater, soil physico-chemical conditions, and crop yield.

eGreenhouse: Robotically positioned, low-cost, open-source CO analyzer and sensor device for greenhouse applications.

Advances in gas sensors and open-source hardware are enabling new options for low-cost and light-weight gas sampling devices that are also robust and easy to use and construct. Although the number of studies investigating these sensors has been increasing in the last few years, they are still scarce with respect to agricultural applications. Here, we present a complete system for high-accuracy measurements of temperature, relative humidity, luminosity, and CO concentrations.

The role of atmospheric conditions in CO and radon emissions from an abandoned water well.

Boreholes and wells are complex boundary features at the earth-atmosphere interface, connecting the subsurface hydrosphere, lithosphere, and biosphere to the atmosphere above it. It is important to understand and quantify the air exchange rate of these features and, consequently their contribution as sources for greenhouse gas (GHG) emissions to the atmosphere. Here, we investigate the effect of atmospheric conditions, namely atmospheric pressure and temperature, on air, CO, and radon transport across the borehole-ambient atmosphere interface and inside a 110-m deep by 1-m diameter borehole in northern Israel.