|Strock, J - UNIVERSITY OF MINNESOTA|
|Porter, P - UNIVERSITY OF MINNESOTA|
Submitted to: Ecological Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 8, 2001
Publication Date: N/A
Technical Abstract: Nitrate contamination impairs surface and ground water quality. Surface water is affected in areas where surface and ground waters are hydrologically connected, and this is especially the case where artificial drainage is necessary for crop production. An experiment was initiated in 1998 to determine whether a fall-seeded winter rye (Secale cereale) cover crop following corn (Zea mays) might be an option for controlling nitrate- nitrogen losses through subsurface drainage in a corn-soybean (Glycine max) rotation. This experiment was conducted in southwest Minnesota on a Webster clay loam (Typic Endoaquoll) soil. The cover crop was planted annually in the fall following corn from the period 1998 to 2000. Considerable variation in climatic conditions from year to year during the project resulted in uneven water flow and nitrate-nitrogen losses from subsurface tile discharge. Variation in environmental conditions also impacted rye biomass, nitrogen uptake by the rye, and residual soil nitrate levels. During the project the rye cover crop reduced water loss from subsurface tile lines with cover crop treatments by up to 23% and lowered nitrate- nitrogen loss by 40 to 50% compared with the corn-soybean rotation without the cover crop. Presence or absence of the cover crop did not affect subsequent soybean yield.