Effect of winter cover cropping practices on maize yield and nutrient cycling

The Illinois Nutrient Loss Reduction Strategy has set Phase 1 reduction milestones for nitrate-nitrogen and total phosphorus of 15 percent and 25 percent, respectively, to the Mississippi River by the year 2025 with the ultimate goal of a 45 percent reduction for both nutrients when compared to average annual riverine loading for years 1980-1996. With estimated levels of 80 percent and 48 percent of nitrate-N and total-P nutrient loads coming from agriculture, the reduction strategy stresses the importance of farmers’ voluntary implementation of best management strategies in order to reach these goals. The purpose of this study was to compare the differences in nutrient cycling of nitrogen and phosphorus from an annual rye winter cover-cropped treatment to a conventional tillage control (fall chisel and spring field cultivation) by measuring preseason fertility, nutrient flux in subsurface tile lines, end of season soil fertility, and crop yields for each treatment. Best management practices consisted of a no-till cover crop scenario with side-dressed nitrogen application at vegetative growth stage 4 (V4). Soil fertility and crop nutrient uptake was measured prior to cover crop termination and again at crop maturity. Throughout the growing season, tile water was collected and analyzed for nitrate and phosphate concentrations. Cumulative losses from April-July 2015 of nitrate nitrogen were calculated at 10.61 and 11.69 kg ha-1 NO3-N for the annual rye treatment and conventional treatment, respectively. Weighted mean nitrate-nitrite nitrogen concentrations in subsurface drainage tile were 4.41 and 6.10 ppm for annual rye and conventional treatments for the same time period. Soil fertility measures of organic matter, nitrogen, and phosphorus did not have a conclusive impact on the final yields of each representative treatment, however, seven out of the top ten yielding annual rye treatments were on the soil with a higher Illinois Soil Nitrogen Test (ISNT). Nitrogen fertilizer rates and timing had a significant impact on final yields with the highest yield being 16.9 Mg ha-1 (271 bu ac-1) at a nitrogen fertilizer rate of 177 kg ha-1 (158 lb ac-1) for the conventional tillage treatment and 16.4 Mg ha-1 (261 bu ac-1) for the no-till annual rye winter cover treatment at a fertilizer rate of 206 kg ha-1 (184 lb ac-1). These results indicate a higher nitrogen rate is necessary for equal yields when a no till winter cover is compared to a conventional tillage plot if water is not a yield limiting factor

Supercritical water oxidation of dioxins and furans in waste incinerator fly ash, sewage sludge and industrial soil

Three environmental samples containing dioxins and furans have been oxidized in the presence of hydrogen peroxide under supercritical water oxidation conditions. The samples consisted of a waste incinerator fly ash, sewage sludge and contaminated industrial soil. The reactor system was a batch, autoclave reactor operated at temperatures between 350°C and 450°C, corresponding to pressures of ~20-33.5 MPa and with hydrogen peroxide concentrations from 0.0 to 11.25 vol%. Hydrogen peroxide concentration and temperature/pressure had a strong positive effect on the oxidation of dioxins and furans. At the highest temperatures and pressure of supercritical water oxidation of 450°C and 33.5 MPa and with 11.25 vol% of hydrogen peroxide, the destruction efficiencies of the individual polychlorinated dibenzo-ρ-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) isomers were between 90% and 99%. There did not appear to be any significant differences in the PCDD/PCDF destruction efficiencies in relation to the different sample matrices of the waste incinerator fly ash, sewage sludge and contaminated industrial soil

IL-27 signaling is crucial for survival of mice infected with African trypanosomes via preventing lethal effects of CD4+ T cells and IFNγ

African trypanosomes are extracellular protozoan parasites causing a chronic debilitating disease associated with a persistent inflammatory response. Maintaining the balance of the inflammatory response via downregulation of activation of M1-type myeloid cells was previously shown to be crucial to allow prolonged survival. Here we demonstrate that infection with African trypanosomes of IL-27 receptor-deficient (IL-27R(-/-)) mice results in severe liver immunopathology and dramatically reduced survival as compared to wild-type mice. This coincides with the development of an exacerbated Th1-mediated immune response with overactivation of CD4(+) T cells and strongly enhanced production of inflammatory cytokines including IFN-gamma. What is important is that IL-10 production was not impaired in infected IL-27R(-/-) mice. Depletion of CD4(+) T cells in infected IL-27R(-/-) mice resulted in a dramatically reduced production of IFN-gamma, preventing the early mortality of infected IL-27R(-/-) mice. This was accompanied by a significantly reduced inflammatory response and a major amelioration of liver pathology. These results could be mimicked by treating IL-27R(-/-) mice with a neutralizing anti-IFN-gamma antibody. Thus, our data identify IL-27 signaling as a novel pathway to prevent early mortality via inhibiting hyperactivation of CD4(+) Th1 cells and their excessive secretion of IFN-gamma during infection with African trypanosomes. These data are the first to demonstrate the essential role of IL-27 signaling in regulating immune responses to extracellular protozoan infections