Modeling agricultural land drainage under spring snowmelt conditions with DRAINMOD

Abstract

There are few computer models that can simulate winter freeze-thaw conditions and spring snowmelt hydrology for agricultural tile drained lands. DRAINMOD, which is used widely to simulate tile drainage flows, has not been extensively applied during colder periods in eastern Canada. This study analyzes the performance of DRAINMOD for surface runoff and subsurface drainage predictions in southern Quebec during spring snowmelt. The model was tested with five years of field data. DRAINMOD was found to be adequate in predicting spring snowmelt hydrology, except for subsurface drainage at one site. It was found that soil characteristics had a major influence on model performance.Résumé : Il existe peu de modèles informatiques qui simulent le gel/dégel d'hiver et l'hydrologie de la fonte des neiges printanière pour les terres agricoles ayant un réseau de drainage par canalisation souterraine. Le modèle DRAINMOD, largement utilisé pour simuler les écoulements des réseaux de drainage par canalisation souterraine, n'a pas été utilisé de manière extensive durant les périodes froides dans l'Est du Canada. La présente étude analyse le rendement de DRAINMOD à prédire de drainage sous la surface et l'écoulement de surface dans le Sud du Québec durant la fonte des neiges printanière. Le modèle a été validé en utilisant cinq années de données de terrain. DRAINMOD s'est révélé être adéquat pour prédire l'hydrologie de la fonte des neiges printanière, sauf pour le drainage sous la surface à un seul site. Les caractéristiques des sols influencent grandement le rendement du modèle. [Traduit par la Rédaction]

Modeling Tile Drainage Outflow in Thin Agricultural Soils with Impermeable under Layer in Newfoundland and Labrador, Canada

“…DRAINMOD is a field-scale hydrologic model first developed by Skaggs R. W. [13] and widely applied in poorly drained agricultural lands [6]. It can simulate surface runoff, subsurface drainage, evapotranspiration (ET), infiltration and WTD (DRAINMOD 6.1).…”

“…where ∆ is the change in the water-free pore space or air volume (cm), D is the lateral drainage (cm), ET is the evapotranspiration (cm), DS is the deep and lateral seepage (cm), F is infiltration (cm), P is the precipitation (cm), RO is the surface runoff (cm) and ∆S is the change in surface water storage (cm). By using the equations, subsurface drainage rates and surface runoff output can be obtained [6]. Infiltration is estimated using the Green-Ampt equation and deep seepage is estimated using Darcy's law.…”

“…It is evident that the soil systems are more complex due to great variations of non-linear processes occur at different rates [5]. Agricultural drainage has several well documented benefits for improving the condition of land for farming operations including better trafficability of soils, permitting farmers to begin field operations earlier in the spring and continue later into the fall [6,7]. Improved drainage [8] is often needed in NL soils is obvious since to help remove surplus water due to precipitation (1000 to 1600 mm annually) greatly exceeding ET.…”

“…While DRAINMOD [22] has been widely applied to drainage design and performance in agricultural fields in mild areas, the model underestimates the effects of soil freezing, and thawing [6]. Freezing and thawing processes [23] affect field hydrology, such as infiltration-runoff relationship during snow melting or rainfall.…”

Development and application of a solute transport model to describe field-scale nitrogen processes during autumn rains

“…The Hooghoudt drainage equation is popular in 1D models (e.g. Mollerup et al, 2014;Morrison et al, 2014) and even in some 2D applications (Abbaspour et al, 2001), but it does not take into account the effect of unsaturated water flow on drain discharge (Yousfi et al, 2014). Mollerup et al (2014) showed that the modeling results were similar when using the Hooghoudt equation in 1D and the Darcy approach in 2D to simulate drain discharge.…”