280-8 Effect of Tillage On Phosphorus Leaching Through Coastal Plain Soils.

Poster Number 1408

See more from this Division: S04 Soil Fertility & Plant Nutrition
See more from this Session: Nutrient Management and Environmental Risk
Tuesday, October 23, 2012
Duke Energy Convention Center, Exhibit Hall AB, Level 1
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Kun Han1, Peter Kleinman2, Ray Bryant2, Mark S. Reiter3, Joshua McGrath4, Clinton Church2 and Arthur Allen5, (1)College of Resources and Environment, Northwest Agriculture and Forestry University, Yangling, China
(2)Curtin Road, USDA-ARS, University Park, PA
(3)Eastern Shore Agricultural Research and Extension Center, Virginia Tech, Painter, VA
(4)University of Maryland, College Park, MD
(5)Agriculture, Food and Resource Sciences, University of Maryland Eastern Shore, Princess Anne, MD
Leaching of phosphorus (P) is a primary water quality concern in soils of the Atlantic Coastal plain where lateral subsurface flow is the dominant P transport pathway. We hypothesize that very high soil P in the upper 2 cm of no-till soils contributes to P leaching via macropore flow and that cultivation will result in overall lower soil P values and less P leaching. We investigated the effect of tillage as a means of reducing P leaching in selected agricultural soils of the Delmarva Peninsula. Intact soil columns of 30-cm diameter and 50-cm length (five replicates) were collected from the Bojac (coarse-loamy, mixed, semiactive, thermic Typic Hapludult), Evesboro (mesic, coated Lamellic Quartzipsamment), and Sassafrass (fine-loamy, siliceous, semiactive, mesic Typic Hapludult) soils. Soil properties range from excessive to somewhat poorly drained and from sand to silty clay loam texure. Soil P stratification with depth was determined by testing the 0-2 cm, 2-10 cm and 10-20 cm layers. To achieve uniform conditions before tillage, soils were pre-irrigated once a week indoors (22-26o C) with 2 mm of water having simulated rainwater chemistry. Tillage was simulated by gently removing and mixing the upper 20 cm of soil and replacing it in the column. Soils were subsequently leached. Differences due to mixing across high and low P soils and soils of varying texture will be presented.
See more from this Division: S04 Soil Fertility & Plant Nutrition
See more from this Session: Nutrient Management and Environmental Risk