Agroforestry as an approach to reduce the water footprint in a profitable way in the Maule Region, Chile

Abstract

The food system is strongly related to the pressure of our planetary boundaries, being responsible for a significant amount of greenhouse gas emissions, land use change, biodiversity loss, biochemical flows, and freshwater use. The dominant system in food production is monoculture, using agrochemicals and motorized equipment. However, monocultures are not the only way to produce food. Agroforestry can reach similar production levels but with environmental benefits such as enhancing biodiversity, reducing erosion, increasing soil carbon sequestration, and reducing agrochemicals pollution. Agroforestry also has a water saving potential, by reduction of runoff and improvement in water infiltration in the soil. The deep roots of trees can access deeper water and redistribute it to the upper layers. Additionally, the increase of shade in the system increases soil moisture and decreases soil evaporation and crop transpiration.

In the Maule Region, Chile, agriculture is strongly focused on fruit monocultures and is the region that consumes most of the fresh water in the country. The region has been affected by a prolonged drought, with an uninterrupted sequence of dry years since 2010. Climate projections estimate that it will get worse in the future, with an increase in temperature and a reduction in precipitation. To address this complex scenario of water scarcity in agriculture, a solution could be to move from conventional agriculture to agroforestry. This study seeks to answer the research question: What is the potential for water savings in the Maule watersheds, moving from conventional agriculture to agroforestry without affecting economic returns?

The study uses the agroforestry project "Huertas A Deo" (HAD) as a case study to analyze the productivity of the agroforestry system, calculate the water footprint, and perform economic and spatial analyses. The results show that the agroforestry system could be highly productive and have a lower water consumption per hectare compared to conventional monocultures. Also, it is economically competitive with the highest profit among the crops analyzed. The spatial analysis shows a five time reduction in the water footprint if all fruit monocultures are transformed to agroforestry. We conclude that the agroforestry system is a powerful tool to face water scarcity in the Maule region while still being competitive against monocultures.