ID 1369 HYDROLOGICAL IMPACT OF THE GREEN GOLD (AVOCADO CULTURE) IN CENTRAL MEXICO; RAINFALL PARTITION AND WATER USE COMPARISON WITH NATIVE FOREST

Abstract

Mexico is the largest producer of avocado (Persea americana) in the world with one third of global fruit production and 180.5 thousand hectares dedicated to this culture, 90% of these are located in the central highlands. In recent years a considerable proportion of this culture had replaced native highland temperate affinity forests. The hydrological impact of the replacement of native forests by avocado plantations is yet to be addressed. We present the first results of the comparison of water consumption between avocado (2 year) saplings and pine native species (Pinus devoniana, P. pseudostrobus) (2.5 year) saplings under field experimental conditions as well as the comparison of rainfall partition between an avocado orchard and a reference native forest site. Sapling water consumption measured gravimetrically to the nearest 5.0 g was normalized by sapling leaf area (m²). Mean normalized water use of avocado was higher 0.541 to 0.987 L/m²/day than mean water use of P. psudostrobus (0.190 L/m²/day) and P. devoniana (0.123 L/m²/day). Regarding rainfall partition, net precipitation was 81.75 % and 83.0 % for the orchard and forest respectively, while troughfall, interception, interception loss, and stemflow percentages were 81.6 and 80.6, 18.4 and 19.4, 18.23 and 17.2, 0.17 and 2.4 for avocado orchard and forest respectively. The largest difference occurred in stemflow, native forest stemflow was nearly 14.1 larger times that of the orchard. The low stemflow proportion at the orchard was attributed to low density of trees 156.2 trees ha-1 and tree morphology. Branch pruning created angles near to 90 º in the lower branches at the orchard preventing intercepted water from flowing into the main stem and dripping off as throughfall. The results suggest that hydrological functioning may be severely affected by land use change from native forest to avocado plantations.

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notch gauges and instruments working in distant areas, quality control of records,
data validation, storage and processing, as well as unplanned changes in
vegetation cover due to Eucalyptus reinvasion, long term funding and institutional
arrays.
CORRESPONDING AUTHOR: Prof. Antonio Lara Aguilar, CHILE,
antoniolaraaguilar@gmail.com
ID 1369
HYDROLOGICAL IMPACT OF THE GREEN GOLD (AVOCADO CULTURE) IN CENTRAL
MEXICO; RAINFALL PARTITION AND WATER USE COMPARISON WITH NATIVE FOREST
Mr. Alberto Gomez-Tagle1, Mr. Rafael Morales-Chavez 2, Mr. Fernando Quiroz3, Mr.
Yonathan García3, Mr. Leonel López-Toledo
1 INIRENA, Universidad Michoacana de San Nicolás de Hidalgo- MEXICO
2 PIDCB, Universidad Michoacana de San Nicolas de Hidalgo – MEXICO
3 Fac. Biol. Universidad Michoacana de San Nicolas de Hidalgo –MEXICO
Mexico is the largest producer of avocado (Persea americana) in the world with
one third of global fruit production and 180.5 thousand hectares dedicated to this
culture, 90% of these are located in the central highlands. In recent years a
considerable proportion of this culture had replaced native highland temperate
affinity forests. The hydrological impact of the replacement of native forests by
avocado plantations is yet to be addressed. We present the first results of the
comparison of water consumption between avocado (2 year) saplings and pine
native species (Pinus devoniana, P. pseudostrobus) (2.5 year) saplings under field
experimental conditions as well as the comparison of rainfall partition between an
avocado orchard and a reference native forest site. Sapling water consumption
measured gravimetrically to the nearest 5.0 g was normalized by sapling leaf area
(m²). Mean normalized water use of avocado was higher 0.541 to 0.987 L/m²/day
than mean water use of P. psudostrobus (0.190 L/m²/day) and P. devoniana (0.123
L/m²/day). Regarding rainfall partition, net precipitation was 81.75 % and 83.0 % for
the orchard and forest respectively, while troughfall, interception, interception loss,
and stemflow percentages were 81.6 and 80.6, 18.4 and 19.4, 18.23 and 17.2, 0.17
and 2.4 for avocado orchard and forest respectively. The largest difference
occurred in stemflow, native forest stemflow was nearly 14.1 larger times that of the
orchard. The low stemflow proportion at the orchard was attributed to low density
of trees 156.2 trees ha-1 and tree morphology. Branch pruning created angles near
to 90 º in the lower branches at the orchard preventing intercepted water from
flowing into the main stem and dripping off as throughfall. The results suggest that
hydrological functioning may be severely affected by land use change from native
forest to avocado plantations.
CORRESPONDING AUTHOR: Mr. Alberto Gomez-Tagle, MEXICO, algomez@umich.mx