The role of vegetation in the redistribution of infiltration in a semi-arid zone
Résumé
The effect of vegetation on the volumes of water that infiltrates into the soil has been extensively
studied, but not the redistribution that occurs radially from trees. This is especially important in
arid and semi-arid areas where water volumes are scarce and water resources management must
be more scrupulous. In the present study, the influence of native vegetation (huizache trees) on
the redistribution of infiltration in a semi-arid zone in the central Mexican plateau was analyzed.
Single ring infiltration tests were carried out with a radial distribution in 2 trees: 4 located inside
the crown of the tree and 4 outside it, in 4 different axes, giving a total of 32 tests per tree.
Likewise, particle size distribution and soil texture analysis were carried out in 4 orthogonal
directions and dry bulk density and initial water content tests at each sampling point were
performed. The results showed a zone of influence located between r / 2 and r of the tree canopy,
where the infiltration is much greater compared to the other points. Based on these results, the
methodology for a third tree was redesigned, in order to characterize various infiltration areas. So
that 3 zones were established within the tree: near, intermediate and far, taking 2 tests in each
zone, in orthogonal direction, and taking a test in each zone of 4 additional axes, a total of 36 tests.
The results of the infiltration tests with this methodology showed similar results to the other two
trees: low infiltration rates close to the tree trunk, high infiltration rates in the area between r / 2
and r of the canopy and again low rates of infiltration in the area outside the crown. Additionally,
the particle size distribution analyzes showed the presence of 4 types of soil: loam, sandy-loam,
clay-loam and silt-loam soil. On the other hand, the initial water content and dry bulk density do
not seem to affect the infiltration process to a greater extent and they vary indiscriminately. The
above suggests that the area between r / 2 and r is the one that captures the highest infiltration
volumes, it may be due to the shadow effect produced by the treetops, although the soil texture
has an influence on the infiltration rates, it does not influence the form of radial redistribution of
tree infiltration.
Domaines
Sciences de l'environnementOrigine | Fichiers produits par l'(les) auteur(s) |
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