Olive Cultivation, its Impact on Soil Erosion and its Progression into Yield Impacts in Southern Spain in the Past as a Key to a Future of Increasing Climate Uncertainty

Abstract

This article is intended as a review of the current situation regarding the impact of olive cultivation in Southern Spain (Andalusia) on soil degradation processes and its progression into yield impacts, due to diminishing soil profile depth and climate change in the sloping areas where it is usually cultivated. Finally, it explores the possible implications in the regional agricultural policy these results might have. It tries to show how the expansion and intensification of olive cultivation in Andalusia, especially since the late 18th century, had as a consequence an acceleration of erosion processes that can be identified by several indicators and techniques. Experimental and model analysis indicates that the rate of soil erosion accelerated since the expansion of mechanization in the late 1950s. In addition, that unsustainable erosion rates have prevailed in the region since the shift to a more intense olive cultivation systems by the end of the 17th Century. Although agroenvironmental measures implemented since the early 2000s have reduced erosion

Characteristics and importance of rill and gully erosion: a case study in a small catchment of a marginal olive grove

“…However, traditional olive orchards were cultivated in hilly areas where other Mediterranean crops were scarce or less productive. Both the erosivity derived from the climate and the flow energy associated to the high slopes, and the low soil cover related with water competition lead to a high susceptibility to water erosion and therefore, a major risk of soil and water degradation (Gómez et al, 2014a). Despite the agro-environmental measures applied since the early 2000s to reduce soil erosion, more effort is needed to provide clear management strategies adapted to the geophysical features of the farms as well as its economic restrictions (Taguas et al, 2011a;Castillo et al, 2013).…”

Exploring the linkage between spontaneous grass cover biodiversity and soil degradation in two olive orchard microcatchments with contrasting environmental and management conditions

“…Over 60 % of the area dedicated to olives is located in Andalusia, the southernmost region of the country. A high risk of soil degradation has been described by multiple authors, such as Goméz-Limón et al (2009) and Gómez et al (2014a), as the result of the interaction of climatological and topographical factors and/or inappropriate soil management. Olive trees have traditionally been cropped under rainfed conditions and on sloping areas where other crops are difficult to grow; they usually provide very low yields or require large investments in order to exploit them properly.…”

“…Olive trees have traditionally been cropped under rainfed conditions and on sloping areas where other crops are difficult to grow; they usually provide very low yields or require large investments in order to exploit them properly. The characteristics of the Mediterranean type of climate, where long dry periods alternate with intense rainfall events, in conjunction with soil management systems that pursue bare soils to minimize water competition by weeds entail a high susceptibility to severe water erosion of the soil (Gómez et al, 2014a). Therefore, the use of cover crops has been promoted for soil protection, given their proven effectiveness in controlling water erosion (Gómez et al, 2004(Gómez et al, , 2009aMárquez-García et al, 2013;Taguas et al, 2013, among others).…”

Assessment of Agri-Environmental Externalities in Spanish Socio-Ecological Landscapes of Olive Groves

“…Several studies [46,47] agree on the importance of improving indicators to quantify these environmental externalities, to be used as a guiding tool both at farm management and environmental policy design levels. In Spain, traditional olive groves are usually located in semi-arid and arid climatic conditions, associated with degraded soils and complex geology and relief [20], with agricultural diffuse pollution being an especially troubling issue [21,48].…”