Rapid denitrification of nitrate-contaminated groundwater in a low-gradient blackwater stream valley

Raulerson, Scott; Jeffers, Johnson B.; Griffiths, Natalie A.; Rau, Benjamin M.; Matteson, Cody; Jackson, C. Rhett

doi:10.1007/s10533-023-01077-0

Cited by 1 publication

(1 citation statement)

References 81 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Despite substantial measurements conducted using laboratory and field techniques to understand the impact of litter application on nutrient leaching, little is known about how the topographical positions (e.g., effect of slope position) across agricultural landscapes affect nutrient leaching dynamics (Julich et al, 2017;Ortega-Pieck et al, 2020;Raulerson et al, 2023;Sigua et al, 2011). To our knowledge, no study has been conducted in no-till pasture systems to evaluate the impact of litter application and preferential flow pathways on nutrient leaching at different topographical positions.…”

Section: Introductionmentioning

confidence: 99%

Preferential flow of phosphorus and nitrogen under steady‐state saturated conditions

Malhotra,

Lamba,

Way

et al. 2024

Vadose Zone Journal

View full text Add to dashboard Cite

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.

show abstract

Section: Introductionmentioning

confidence: 99%