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Repeated broiler litter application on agricultural lands can cause nutrient enrichment of subsurface effluent, especially with the existence of preferential flow through soil macropores. Previous studies quantifying soil macropores have not attempted to establish a connection of soil macropore characteristics with the subsurface nutrient (nitrogen [N] and phosphorus [P]) losses, across different topographical locations in the field. This study investigated the effect of broiler litter application and preferential flow on subsurface nutrient transport (N and P) at different topographical positions (upslope, midslope, and downslope) in a no‐till pasture field located in Alabama, USA. Twelve intact soil columns (150 mm id and 500 mm length) were used, and the nutrient leaching measurements from laboratory experiments were linked to soil macropore characteristics quantified using X‐ray computed tomography image analysis and solute transport modeling. Treatments included surface broadcast broiler litter (5 Mg ha−1, on dry basis) and unamended control. Leachates were analyzed for dissolved reactive P (DRP), total P (TP), and nitrate + nitrite‐N (NO3− + NO2−–N). The bromide breakthrough curves provided evidence of preferential flow in all columns. Litter application significantly increased leachate P concentrations, and average TP and DRP concentrations were significantly higher in the leachate from upslope columns compared to those at downslope location. The NO3−–N concentrations in leachate exceeded the US EPA drinking water standard of 10 mg L−1 in all the treatment columns. The highest flow‐weighted mean concentrations of TP and DRP, at 2.7 and 2.5 mg L−1, respectively, were recorded in the upslope columns. Soil physicochemical properties and nutrient leaching losses varied substantially across topographical positions, indicating a need for variable litter application rates to reduce P build‐up and subsequent leaching in vulnerable locations within the field. The relevance of the effect of topographic position on nutrient leaching found in this study should be further tested by investigating a wider range of slopes and soil types in pastures. Core Ideas: Phosphorus and nitrogen concentrations in the leachate varied as a function of slope position.Breakthrough curves and X‐ray computed tomography (CT) analysis provided evidence of preferential flow.Solute transport was well‐fitted by the two‐region physical nonequilibrium model.Broiler litter application significantly increased phosphorus leaching under saturated conditions. [ABSTRACT FROM AUTHOR]

Use of broiler litter (BL) for agronomic purposes requires balancing the amount of nitrogen (N) needed to maximize crop yield while reducing environmental N footprints. This 2‐yr study (2018–2019) compared the effects of N source (BL or urea), application rate [0, 168, and 336 kg total N ha–1), and application timing (single or split) on corn (Zea mays L.) yield and environmental nitrogen loss (ENL) on three Alabama soil types. A field‐scale partial N budget was developed by accounting for known N inputs and outputs. The difference between the input and output in the partial N budget was considered as ENL, which comprised of N losses via runoff, leaching, volatilization, and denitrification. Application of BL increased corn yield relative to urea at only one site. At the responsive site, BL application rate had no significant effect on corn yield, but pre‐plant single application of BL produced 52% greater corn yield compared with split application. At other two sites where yield was lower for corn receiving BL, corn yield increased significantly with increasing BL application rate. Total N loss to the environment ranged between 32 and 52% of the N input. The influence of N source on ENL varied by site however losses increased with increasing N fertilization rates. Application timing did not influence ENL at two of three sites. This study showed that a lower application rate (168 kg ha–1) of BL prior to planting was a better management strategy for increasing corn yield, while reducing environmental N loss. Core Ideas: Broiler litter increased corn yield relative to urea only where soil N was nonlimiting.Split applications of broiler litter produced lower corn yield than single pre‐plant applications.Total N loss to the environment ranged from 32 to 52% of the N input.Nitrogen losses to the environment increased with increasing N application rate. [ABSTRACT FROM AUTHOR]

We report the synthesis of Sr doped ZnO (Zn1-xSrxO with x=0, 0.01, 0.02, 0.03 and 0.04) by three different methods to study the dependence of synthesis on the structural and optical properties. The study is a comparison of auto combustion, citrate gel and co-precipitation method derived oxide samples. A comparative analysis like this enabled us to identify the right method for doping Sr in the ZnO matrix with minimum additional reflections. Further analysis revealed the formation of defects in the crystal can act as potential phonon scattering centres for thermoelectric application. Absorption data reveal that, while auto combustion method led to excellent absorption in the visible light region, only 3% doped ZnO by citrate gel exhibited the same and was completely absent in the materials derived from traditional co-precipitation technique. Such absorption between 400 to 700 nm by just a mono doped binary oxide may lead to excellent photocatalytic dye degradation properties. Also, it was found that Burstein Moss shift and introduction of Sr-3d levels in conduction band can further enhance the electrical conductivity which again is a way to tune thermoelectric figure of merit. Hence studying such a simple binary oxide doped with Sr becomes important as it can be a very good multi multifunctional material. [ABSTRACT FROM AUTHOR]

Aluminum doped ZnO ( Zn 1 − x AlxO, x = 0. 0 1 , 0.02, 0.03 and 0.04) (AZO) nanoparticles were synthesized using citrate-gel method. We report the effect of aluminum doping along with variation of metal to citrate ratio on structural and optical properties of AZO nanoparticles with crystallite size optimization. The X-ray diffraction analysis confirmed Wurtzite crystal structure wherein the crystallite size was within the range of 15–40 nm. Optical properties were studied with the help of UV-Visible spectroscopy. Bandgap calculated using Tauc plot is found to be between the range of 2.39–2.75 eV and morphological analysis using Scanning Electron Microscopy (SEM) showed the distribution of synthesized material. [ABSTRACT FROM AUTHOR]