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Agricultural intensification has greatly affected biodiversity in recent decades. One common and recent transformation that has taken place in Mediterranean countries is olive grove intensification, although its effects on biodiversity have rarely been studied.In the present study, we investigated the effect of soil management practices, with versus without soil cover crops, on the arthropod abundance, richness, diversity and species composition in Andalusia olive groves, South Spain.The results obtained show that these soil cover crops positively affect the diversity of arthropods, along with other variables such as the diversity of the plant community and Shannon index of the landscape. By contrast, the number of arthropods was higher in olive groves with bare ground as a result of the abundance of two families (Entomobryidae and Aeolothripidae), which comprised more than 50% of all the individuals collected.Rank abundance diagrams and multivariate analyses showed differences between the two types of soil management systems with respect to the composition of families.In conclusion, soil cover crops strongly improve the diversity of arthropods in olive orchards, which helps to maintain biodiversity in these intensive agroecosystems at the same time as improving other ecosystems services, such as soil fertility and the prevention of soil erosion. [ABSTRACT FROM AUTHOR]

Abstract: Environmentally friendly control measures are necessary for the olive fruit fly Bactrocera oleae (Rossi). Predation of pupae in soil should be better understood because it contributes to the natural control of pest populations. A time course field trial was carried out in 2015 and 2016 in 15 olive orchards selected to represent a gradient of landscape complexity. Exclusion cages were used to estimate predation rate. A combination of tillage intensity and soil coverage by herbaceous vegetation, hereafter referred to as soil condition, was also assessed as a factor affecting predation rate. The viability of the pupae recovered from the field was also evaluated. Predation was higher in the autumn than in late winter–early spring, although predation rate values were generally quite low. Landscape structure affected predation. In the autumn, the area of Mediterranean scrublands promoted predation in the olive groves. In late winter–early spring, weak tendencies were registered. Soil condition affected predation in autumn as well. The intense tillage and poor soil coverage were related to lower values of predation rate. To favour conservation biological control of B. oleae by pupae predation, it is advisable to reduce the intensity of soil management, especially in autumn, and to preserve areas of scrublands surrounding the olive groves. [ABSTRACT FROM AUTHOR]

Landscape ecology studies on pest control have focused mainly on annual crops and natural enemies, whereas more studies measuring pest pressure on perennial crops are needed., The relationships between the abundance and damage by Bactrocera oleae ( Rossi) and different landscape indices were analyzed using data gathered by a regional network during 2009, 2010 and 2011 in Jaén, Spain. Eleven indices of landscape composition and configuration calculated at six different spatial scales (radii of 500, 600, 750, 1000, 1500 and 2000 m) were used in correlation analyses., Significant correlations between abundance and some indices were observed primarily during Julian days 236-264 (24 August to 21 September) 2010. These correlations were negative with edge density, the Shannon landscape diversity index and the number of patches, and were positive with patch size standard deviation and mean patch size., Linear mixed-effects models were used to identify the indices most strongly related to the abundance of olive flies. These indices were mean patch size, edge density at 500-750 m and the Shannon landscape diversity index, as well as the number of patches at 1000-2000 m., These results suggest that greater landscape complexity may contribute to reduced numbers of B. oleae. More studies are needed to establish how to reduce olive fruit fly damage. [ABSTRACT FROM AUTHOR]