Cover crop effects on nitrogen load in tile drainage from Walnut Creek Iowa using root zone water quality (RZWQ) model

J.W. Singer, R.W. Malone, D.B. Jaynes and L. Ma

Agricultural Water Management, 2011, vol. 98, issue 10, 1622-1628

Abstract: Studies quantifying winter annual cover crop effects on water quality are mostly limited to short-term studies at the plot scale. Long-term studies scaling-up water quality effects of cover crops to the watershed scale provide more integrated spatial responses from the landscape. The objective of this research was to quantify N loads from artificial subsurface drainage (tile drains) in a subbasin of the Walnut Creek, Iowa (Story county) watershed using the hybrid RZWQ-DSSAT model for a maize (Zea mays L.)-soybean [Glycine max (L.) Merr.] and maize-maize-soybean rotations in all phases with and without a winter wheat (Triticum aestivum L.) cover crop during a 25-year period from 1981 to 2005. Simulated cover crop dry matter (DM) and N uptake averaged 1854 and 36 kg ha-1 in the spring in the maize-soybean phase of the 2-year rotation and 1895 and 36 kg ha-1 in the soybean-maize phase during 1981-2005. In the 3-year rotation, cover crop DM and N uptake averaged 2047 and 44 kg ha-1 in the maize-maize-soybean phase, 2039 and 43 kg ha-1 in the soybean-maize-maize phase, and 1963 and 43 kg ha-1 in the maize-soybean-maize phase during the same period. Annual N loads to tile drains averaged 29 kg ha-1 in the maize-soybean phase and 25 kg ha-1 in the soybean-maize phase compared to 21 and 20 kg ha-1 in the same phases with a cover crop. In the 3-year rotation, annual N loads averaged 46, 43, and 45 kg ha-1 in each phase of the rotation without a cover crop and 37, 35, and 35 kg ha-1 with a cover crop. These results indicate using a winter annual cover crop can reduce annual N loads to tile drains 20-28% in the 2-year rotation and 19-22% in the 3-year rotation at the watershed subbasin scale over a 25-year period.

Keywords: Subbasin; scale; Crop; rotation; Winter; wheat; cover; crop; Nitrate; leaching (search for similar items in EconPapers)
Date: 2011
References: View complete reference list from CitEc
Citations: View citations in EconPapers (6)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0378377411001296
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:agiwat:v:98:y:2011:i:10:p:1622-1628

Access Statistics for this article

Agricultural Water Management is currently edited by B.E. Clothier, W. Dierickx, J. Oster and D. Wichelns

More articles in Agricultural Water Management from Elsevier
Bibliographic data for series maintained by Catherine Liu ().