Estimation of soil mobilization rates by a rainy period and intense tillage practices in vineyards—A case study in the Maule region (Chile)

Abstract

Winemaking in Chile is a long tradition that is recognized around the world. It is especially important in the Maule region where more than 40% of the total wine in the country is produced. However, there is a lack of studies related to soil erosion in vineyards in Chile, especially considering the extreme rainfall events that occur in the country. This research estimates soil erosion mobilization rates before and after a rainy season between April 2020 and May 2020 using the "improved stock unearthing method" on two inter-row plots in a vineyard located in the Maule region of Chile. This method relies on the graft union as a bioindicator for assessing soil surface-level changes. Maps of the soil surface were obtained to show how soil depletion and accumulation points within the inter-row areas could be detected. It has been estimated that a total soil mobilization of 85.7 and 130 Mg ha yr(-1) had occurred in the inter-row areas 1 and 2, respectively, since the establishment of the plantation. However, a single rain event mobilized soil at rates of 5.5 and 3.5 Mg ha yr(-1), respectively, in the inter-row areas 1 and 2. We have demonstrated that erosive processes present in the study area exceed the rates of soil formation and the tolerable rates of erosion on a global scale. The results allow re-thinking of agricultural practices and management of soil systems to improve the sustainability of conventional Chilean vineyards and their soils.