Cornelis, W.M.

Gabriel, D.

McLaren, Rob. G.

Soto, G.

Verbist, K.

English

Wageningen UR (University & Research Centre): Publication System

21st century hydrological modelling for optimizing ancient water 
harvesting techniques 
K. Verbist1, W.M. Cornelis1, Rob G.McLaren2, G. Soto3, D. Gabriels1 
1 Dept. of Soil Management - International Centre for Eremology, Ghent University, Coupure links, 653, B-
9000 Gent, Belgium 
2 Department of Earth Sciences, University of Waterloo, Canada 
3 Centro del Agua para Zonas Áridas y Semiáridas de América La� na y el Caribe, La Serena, Chile 
 
ABSTRACT 
In order to increase dryland productivity, water harvesting techniques (WHT) have received renewed attention, 
leading to their massive implementation in marginal drylands. However, the tools to evaluate their efficiency 
under a wide range of conditions still need to be developed. For a case study in the arid central-northern zone of 
Chile, a fully coupled 3D surface-subsurface hydrological model based on the Richards’ and the Saint Venant 
equations was parameterized with detailed runoff and soil-water content data collected during simulated rainfall 
from a 6 x 2 m experimental plot including a catchment area and infiltration trench. Using six responsive 
parameters identified by a global sensitivity analysis surface and subsurface flow processes were calibrated 
simultaneously. The calibrated model accurately reproduced observed soil moisture contents (R2 0.92) and 
runoff amounts (R2 0.97), and represented the overflowing infiltration trench, which is a clear improvement over 
existing frameworks. A comparative analysis with a natural slope demonstrated that the trench was efficient in 
capturing runoff under high rainfall intensities, such as the one simulated, resulting in a significant decrease 
(46%) of runoff. However, when extended to natural rainfall seasons, runoff water harvesting was insufficient in 
dry, normal and wet years, while only under very wet conditions 55% of the potential runoff was effectively 
harvested and stored in the soil profile. As such, this test case shows the importance of correct water harvesting 
design to become an effective tool in dryland management, taking both soil physical and climatic constraints 
into account. The model was further tested on a much larger scale of two ca. 3 ha large catchments in semi-arid 
Chile, one with infiltration trenches for rainwater harvesting and one without. Good agreement was observed 
between measured and simulated runoff out the catchment outlet.  
 
Keywords: hydrological model, water harvesting, surface flow, subsurface flow, parameterization, Chile  


21st century hydrological modelling for optimizing ancient water harvesting techniques

https://library.wur.nl/ojs/index.php/AE2012/article/download/12413/11918

21st century hydrological modelling for optimizing ancient water harvesting techniques

Abstract

Similar works

Full text

Available Versions

Wageningen UR (University & Research Centre): Publication System