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Excess NO3 leaching from the agricultural Midwest via tile drainage water has contributed to both local drinking water and national Gulf of Mexico benthic hypoxia concerns. Both in‐field and edge‐of‐field practices have been designed to help mitigate NO3 flux to surface waters. Edge‐of‐field practices focus on maximizing microbial denitrification, the conversion of NO3 to N2 gas. This study assessed denitrification rates from two saturated riparian buffers (SRBs) for 2 yr and a third SRB for 1 yr, for a total of five sample years. These SRBs were created by diverting NO3–rich tile drainage water into riparian buffers soils. The SRBs in this study removed between 27 and 96% of the total diverted NO3 load. Measured cumulative average denitrification rate for each SRB sample year accounted for between 3.7 and 77.3% of the total NO3 removed. Both the cumulative maximum and 90% confidence interval denitrification rates accounted for all of the NO3 removed by the SRBs in three of the five sample years, indicating that denitrification can be a dominant NO3 removal mechanism in this edge‐of‐field practice. When adding the top 20 cm of each core to the cumulative denitrification rates for each SRB, denitrification accounted for between 33 and over 100% of the total NO3 removed. Buffer age (time since establishment) was speculated to enhance denitrification rates, and there was a trend of the soil closer to the surface making up the majority of the total denitrification rate. Finally, both NO3 and C could limit denitrification in these SRBs. Core Ideas: Denitrification accounted for 3.7 to 77.3% of NO3 removal within saturated riparian buffers.We hypothesized that saturated riparian buffer denitrification increased with buffer age.Soil surface horizons had a greater denitrification rate than deeper horizons.A higher water table led to greater NO3 removal through denitrification.The saturation status of a buffer did not significantly affect denitrification rates. [ABSTRACT FROM AUTHOR]

Background: Medication synchronization (med-sync) aligns patients' monthly or quarterly chronic medications to a predetermined single pickup date at a community pharmacy. The study objective was to examine med-sync enrollment disparities based on Medicare beneficiaries' predisposing, enabling, and need characteristics.Methods: This was a retrospective cohort study using a Medicare dataset of beneficiaries receiving medications from pharmacies that self-identified as providing med-sync. Medicare beneficiaries who were continuously enrolled in fee-for-service medical and pharmacy benefits during the study period (2014-2016) were included. Study cohorts (med-sync and non-med-sync patients) were defined, and bivariate and multivariable logistic regression analyses were performed. Andersen's Health Services Utilization Model guided our inclusion of predisposing, enabling, and need characteristics to examine for association with med-sync enrollment.Results: A total of 170,180 beneficiaries were included, of which 13,193 comprised the med-sync cohort and 156,987 comprised the non-med-sync cohort. Bivariate logistic regression analysis revealed statistically significant differences (P < 0.05) in cohorts based on age, geographic region, type of residence, number of unique chronic medications, comorbidities, outpatient visits, and inpatient hospitalizations. Beneficiaries had higher odds of being enrolled in med-sync with increasing age (adjusted odds ratio [AOR] 1.003 [95% CI 1.001-1.005]) and if they resided in the Northeast (AOR 1.094 [95% CI 1.018-1.175]), South (AOR 1.109 [95% CI 1.035-1.188]), and West (AOR 1.113 [95% CI 1.020-1.215]) than those in the Midwest. Beneficiaries residing in nonmetro areas had lower odds of enrollment (AOR 0.914 [95% CI 0.863-0.969]) than those in metro areas. Beneficiaries with previous fewer inpatient hospitalizations (AOR 0.945 [95% CI 0.914-0.977]) were more likely to be enrolled, and those with more outpatient visits (AOR 1.003 [95% CI 1.001-1.004]) were more likely to be enrolled. Those taking a higher number of oral chronic medications (AOR 1.005 [95% CI 1.002-1.008]) had greater odds of enrollment in med-sync.Conclusions: Med-sync program expansion opportunities exist to address potential enrollment disparities based on age, geographic region, metropolitan area, and prior health utilization. Further studies are needed to develop and examine strategies among pharmacies to improve med-sync enrollment outreach to these subgroups of patients. [ABSTRACT FROM AUTHOR]

The article presents a study on the effects of nitrogen fertilizer on soil carbon balances in the agricultural systems in Midwestern U.S. The impacts of two major processes that determine the soil carbon balance, the rates of organic-carbon inputs and decay at four levels of nitrogen fertilization were evaluated. The study found that the selection of crops with high belowground net primary production is a more effective management practice for increasing soil carbon sequestration. It states that the best predictor of long-term soil carbon storage is the quantity of belowground organic-carbon inputs.

This article discusses the use of rye cover and gamagrass strips to reduce the nitrate runoff of subsurface tiled drainage in the Midwest U.S. According to the authors, nitrate concentrations and nitrate loads were significantly reduced in subsurface drainage after rye winter cover treatments but cumulative annual drainage was not reduced. However, permanent gamagrass strips did not significantly reduce nitrate concentrations, nitrate loads or annual drainage. They concluded that rye winter cover after soybean and corn crops can reduce nitrates in surface waters impacted by subsurface drainage systems.

The article presents a comparison of carbon substrates for denitrification of subsurface drainage water. Contamination of surface waters is in part due to the water nitrate in the fields of tile drained corn and soybean in the U.S. Midwest. Reducing nitrate concentrations can be done by biofilters based on denitrification although external carbon supply is needed. A laboratory study was conducted to look at the capacity four organic materials to carbon substrates for denitrification biofilters. In the laboratory study, woodchips, woodchips with soybean oil, cornstalks, and cardboard fibers were used. Cornstalks supported more denitrification than the others.