Cardinal chains 9911/14/2022 Intensification has also involved major changes in orchard structure, with intensive orchards characterized by high densities of relatively small and young trees (200–450 trees ha −1) planted at regular intervals, and superintensive orchards characterized by very high densities (1500–2000 trees ha −1) of dwarf tree varieties planted as hedgerows 21, 22. Over the past decades, these orchards have been replaced by larger and more intensively managed ones, that are irrigated, spray insecticides to control pests and herbicides to reduce the herbaceous layer, and have mechanical harvesting 15, 16. The soil is often tilled to remove vegetative cover between trees 17, 18, but a herbaceous layer may be retained under organic production models 19, 20. 100 trees ha −1), and are managed with reduced or no use of agrochemicals and mechanisation 15, 16. Traditional orchards are rain fed, typically composed of large and old trees (> 50 years) planted at low densities (ca. Cultivation of this crop is largely concentrated in the Mediterranean biodiversity hotspot 10, 11, where olive orchards have been part of rural landscapes for millennia 12 and harbour considerable arthropod diversity 13, 14. 1753) is one of the crops that has rapidly expanded and intensified in recent decades, mainly due to a combination of agricultural policies and market mechanisms 8, 9. Addressing these issues is thus critical to understand if and how intensified agriculture can be managed to mitigate negative impacts on arthropods. Moreover, little is known about whether different arthropod taxa and trophic groups are equally vulnerable to intensification 3. However, information about the impacts of intensification is still lacking for many crops. #Cardinal chains 99 drivers#Agricultural intensification is considered one of the main drivers of arthropod declines, both at local and landscape scales 3, 7. Overall, results suggest that retaining herbaceous cover, reducing agrochemical inputs and preserving natural woody elements in the landscape, may contribute to mitigate impacts of olive farming intensification on canopy arthropods, particularly on beneficial species.Īrthropods are declining in many terrestrial ecosystems 1, 2, 3, posing a serious threat to ecosystem functioning and human wellbeing, given their key role in ecosystem processes and services 4, 5, 6. The negative effects of intensification were stronger in spring and summer than in autumn, and parasitoids and predators were particularly affected. The abundance of a specialized olive pest was lower in landscapes with higher woodland cover. Decreased abundance was associated with changes in orchard structure, lower herbaceous cover, and higher herbicide and insecticide use. We found no changes in the diversity of arthropod taxa across intensification levels after correcting for sample coverage, but arthropod abundance declined markedly along the intensification gradient. We evaluated how the arthropod community varied across intensification levels, and in response to orchard structure, management and landscape context. Canopy arthropods were vacuum-sampled at 53 sites representing the three orchard intensification levels, in spring, summer and autumn 2017. Intensification involves the increased use of agrochemicals, mechanisation and irrigation, but also structural changes from traditional orchards with low densities of large and old trees, to intensive and superintensive orchards with high to very high densities of smaller and younger trees, respectively. We investigated the impacts of olive farming intensification on canopy-dwelling arthropods in the Mediterranean region. However, information about the impacts of intensification is still limited for many crops, as is our understanding of the responses of different arthropod taxa and trophic groups, thus hindering the development of effective mitigation measures. Arthropod declines have been linked to agricultural intensification.
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