Spatially Distributed Water Fluxes in an Andisol under Banana Plants: Experiments and Three‐Dimensional Modeling

Abstract

means, electronic or mechanical, including photocopying, recording, or any informa on storage and retrieval system, without permission in wri ng from the publisher. S S : V Z M Water fl uxes in the subsurface of forested and agricultural ecosystems vary spa ally across wide ranges because of several interconnected phenomena. On the one hand, subsurface environments are o en highly heterogeneous. On the other hand, infi ltra on water is o en distributed unevenly due to aboveground intercep on and redistribu on of rainfall by the plant canopy. These phenomena have important hydro-ecological consequences because they signifi cantly aff ect groundwater recharge and nutrient leaching. Field experiments involving subsurface lysimeters and tensiometers were performed to quan fy the spa al distribu on of fl uxes in an Andisol under a banana plant (Musa acuminata Colla).Wick lysimeters were installed at a depth of 70 cm at several loca ons with respect to the banana stem to measure the spa al distribu on of subsurface water fl uxes. Collected experimental data were simulated using the HYDRUS so ware package, which numerically solves the Richards equa on describing three-dimensional variably saturated water fl ow in the subsurface. Spa ally distributed drainage fl uxes were well reproduced with the numerical model. Due to the impact of stemfl ow, drainage volumes under the banana stem were up to six mes higher than in the row downstream from the stem, as well as between rows, as these areas were sheltered from direct rainfall by the banana leaves and received only throughfall.

Evaluation of water movement and nitrate dynamics in a lysimeter planted with an orange tree

“…Additionally, since in the present study we dealt with a tree, for which the root distribution development over time is not as fast as observed for seasonal crops like cereals, the root development was considered relatively constant for the modelling purpose. Hence, a static root distribution and variable atmospheric conditions produced a good approximation of plant uptake, as has been revealed in a number of earlier studies that used HYDRUS for modelling purposes (Sansoulet et al, 2008;Phogat et al, 2012Phogat et al, , 2013Ramos et al, 2011Ramos et al, , 2012Tournebize et al, 2012) …”

Inverse estimation of soil hydraulic properties under oil palm trees

“…Liang et al (2007) observed that cumulative stemflow per unit infiltration area along the downslope side of a tree trunk was nearly 20 times cumulative open-area rainfall. Sansoulet et al (2008) similarly found that stemflow caused the infiltration rates around a banana stem to be up to six times higher than in the throughfall areas. Several other studies observed differences between stemflow and throughfall rates, including for olive trees (Gomez et al, 2002), banana plants (Cattan et al, 2009), tall stewartia (Liang et al, 2009), and ponderosa pine (Guan et al, 2010).…”

“…Previous studies have shown that stemflow can be a major source of tree-induced infiltration and subsequent flow in and below the soil root zone, including recharge (Aboal et al, 1999;Gomez et al, 2002;Liang et al, 2007Liang et al, , 2011Pressland, 1976;Sansoulet et al, 2008;Tanaka et al, 1996). Liang et al (2007) observed that cumulative stemflow per unit infiltration area along the downslope side of a tree trunk was nearly 20 times cumulative open-area rainfall.…”

Selected HYDRUS modules for modeling subsurface flow and contaminant transport as influenced by biological processes at various scales

“…In addition to natural subsurface heterogeneity, infiltrating water is often distributed unevenly due to above-ground interception and redistribution of rainfall by plant canopies (Sansoulet et al 2008). Transpiration and evaporation often also vary widely over the landscape as a function of geographical location, slope exposure, plant species, and many other factors.…”