A Comparative Analysis of Soil Loss Tolerance and Productivity of the Olive Groves in the Protected Designation of Origin(PDO) Areas Norte Alentejano (Portugal) and Estepa (Andalusia, Spain)

Abstract

Olive groves are Mediterranean systems that occupy more than 2.5 M ha in Spain and 0.352 M ha in Portugal. Assuming the differences between both countries in terms of olive grove regulation and considering their multifunctionality, it is useful to implement agronomic indices to estimate their sustainability. The Soil Loss Tolerance Index (SLTI) and the Soil Productivity Index (SPI) are two such indices. We calculated both indices in the Protected Designation of Origin (PDO) Norte Alentejano (Portugal). The SLTI index was adapted considering specific variables of the analysed olive groves (i.e., SLTIog). The values obtained were compared with those previously estimated for PDO Estepa (Spain). The negative impacts of erosion and the underlying agricultural practices on the sustainability of olive groves became evident, resulting in decreased soil productivity at the regional level. The SLTIog index showed higher values for crops, being a more realistic tool to analyse sustainability. A higher soil loss tolerance was detected for integrated groves in the PDO Norte Alentejano than for PDO Estepa due to the shorter age of olive cultivation in Portugal, with incipient soil impacts. These indices provide information on the degree of soil erosion, allowing farmers and decision-makers to apply practices to maximise the sustainability of olive groves.To the University Complutense of Madrid, for awarding the lead author a short-term fellowship through which this research could be carried out. To MED-Universidade de Évora (Portugal), for providing to the main author with the opportunity to jointly perform field work and analytical tasks in Portugal. The time devoted by J.M.-R. and T.P.-C. to retrieve and treat the data and to write and revise the article has received partial funding from the following sources: (a) FCT—Foundation for Science and Technology (Portugal) under the Project UIDB/05183/2020; (b) SUSTAINOLIVE research project (https://sustainolive.eu/?lang=en [accessed on: 29 March 2021]), funded by the PRIMA EU program. Lastly, we thank María Aurora Rodríguez Sousa for her support and advice