Monitoring and modelling draining and resident soil water nitrate concentrations to estimate leaching losses

M. van der Laan, R.J. Stirzaker, J.G. Annandale, K.L. Bristow and C.C. du Preez

Agricultural Water Management, 2010, vol. 97, issue 11, 1779-1786

Abstract: Quantifying nitrogen (N) losses below the root zone is highly challenging due to uncertainties associated with estimating drainage fluxes and solute concentrations in the leachate. Active and passive soil water samplers provide solute concentrations but give limited information on water fluxes. Mechanistic models are used to estimate leaching, but require calibration with measured data to ensure their reliability. Data from a drainage lysimeter trial under irrigation in which soil profile nitrate (NO3-) concentrations were monitored using wetting front detectors (passive sampler) and ceramic suction cups (active sampler) were compared to NO3- concentrations in draining and resident soil water as simulated by the research version of the Soil Water Balance model (SWB-Sci). SWB-Sci is a daily time-step, cascading soil water and solute balance model that provides draining NO3- concentrations by accounting for incomplete solute mixing. As hypothesized, suction cup concentrations aligned closely with resident soil water concentrations, while wetting front detector concentrations aligned closely with draining soil water NO3- concentrations. These results demonstrate the power of combining monitoring and modelling to estimate NO3- leaching losses. Access to measured draining and resident NO3- concentrations, especially when complemented with modelled fluxes, can contribute greatly to achieving improved production and environmental objectives.

Keywords: Nitrate; leaching; Monitoring; Modelling; Draining; and; resident; soil; water; SWB-Sci (search for similar items in EconPapers)
Date: 2010
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (7)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0378-3774(10)00209-X
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:97:y:2010:i:11:p:1779-1786

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 ().