Eficiencia del uso del agua de un viñedo y su relación con porosidad del suelo

Abstract

The objective of this study was to determine the effect of the waterholding capacity of soil given its porosity (η), and its relationship with the intrinsic water-use efficiency (WUEi) and the marginal productivity of the water (MPW), in a vineyard planted with Vitis vinífera L. (Shiraz variety). This study was conducted in two vineyards having different soil porosity, on land belonging to the San Lorenzo wine company in Parras, Coahuila during the March-September growing cycle, 2014. The ηwas calculated based on the bulk and particle density. Changes in the soil's water content were evaluated at each vineyard using TDR probes, and the WUEi was determined based on CO2 assimilation and evapotranspiration rates, with an Eddy system in each vineyard. The soil porosity reached 0.385 cm3/cm3 (highest value) in one of the vineyards and 0.306 cm3/cm3 in the other, which corresponded to a difference of 25.82%. This difference in soil porosity indicates a large difference in the volumetric soil water content, resulting in higher evapotranspiration and CO2 assimilation rates. The highest water availability did not affect the intrinsic water-use efficiency. And throughout the growing stages of the plants, the marginal productivity of the water was on average 26.64% higher in the vineyard that had more soil porosity.