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Agricultural intensification not only increases food production but also drives widespread biodiversity decline. Increasing landscape heterogeneity has been suggested to increase biodiversity across habitats, while increasing crop heterogeneity may support biodiversity within agroecosystems. These spatial heterogeneity effects can be partitioned into compositional (land-cover type diversity) and configurational heterogeneity (land-cover type arrangement), measured either for the crop mosaic or across the landscape for both crops and semi-natural habitats. However, studies have reported mixed responses of biodiversity to increases in these heterogeneity components across taxa and contexts. Our meta-analysis covering 6397 fields across 122 studies conducted in Asia, Europe, North and South America reveals consistently positive effects of crop and landscape heterogeneity, as well as compositional and configurational heterogeneity for plant, invertebrate, vertebrate, pollinator and predator biodiversity. Vertebrates and plants benefit more from landscape heterogeneity, while invertebrates derive similar benefits from both crop and landscape heterogeneity. Pollinators benefit more from configurational heterogeneity, but predators favour compositional heterogeneity. These positive effects are consistent for invertebrates and vertebrates in both tropical/subtropical and temperate agroecosystems, and in annual and perennial cropping systems, and at small to large spatial scales. Our results suggest that promoting increased landscape heterogeneity by diversifying crops and semi-natural habitats, as suggested in the current UN Decade on Ecosystem Restoration, is key for restoring biodiversity in agricultural landscapes.

Our aim was to assess the effect of agricultural management and landscape context of the olive groves on the flower-visiting insect community.

Our aim was to characterize the seeds of fleshy fruit species mobilized by avian frugivores in the olive grove farms of the Guadalquivir valley in Andalusia (South Spain), considering a landscape homogenization gradient. We further assessed the contribution of different frugivores to this function by mist-netting and scat collection. We differentiated two habitats within olive farms: olive grove matrix and seminatural woodland patches.

[ES] Las abejas son un grupo extremadamente diverso con más de 1000 especies descritas en la península ibérica. Además, son excelentes polinizadores y aportan numerosos servicios ecosistémicos fundamentales para la mayoría de ecosistemas terrestres. Debido a los diversos cambios ambientales inducidos por el ser humano, existen evidencias del declive de algunas de sus poblaciones para ciertas especies. Sin embargo, conocemos muy poco del estado de conservación de la mayoría de especies y de muchas de ellas ignoramos cuál es su distribución en la península ibérica. En este trabajo presentamos un esfuerzo colaborativo para crear una base de datos de ocurrencias de abejas que abarca la península ibérica e islas Baleares que permitirá resolver cuestiones como la distribución de las diferentes especies, preferencia de hábitat, fenología o tendencias históricas. En su versión actual, esta base de datos contiene un total de 87 684 registros de 923 especies recolectados entre 1830 y 2022, de los cuales un 87% presentan información georreferenciada. Para cada registro se incluye información relativa a la localidad de muestreo (89%), identificador y colector de la especie (64%), fecha de captura (54%) y planta donde se recolectó (20%). Creemos que esta base de datos es el punto de partida para conocer y conservar mejor la biodiversidad de abejas en la península ibérica e Islas Baleares, [EN] Bees are a diverse group with more than 1000 species known from the Iberian Peninsula. They have increasingly received special attention due to their important role as pollinators and providers of ecosystem services. In addition, various rapid human-induced environmental changes are leading to the decline of some of its populations. However, we know very little about the conservation status of most species and for many species, we hardly know their true distributions across the Iberian Peninsula. Here, we present a collaborative effort to collate and curate a database of Iberian bee occurrences to answer questions about their distribution, habitat preference, phenology, or historical trends. In total we have accumulated 87 684 records from the Iberian Peninsula and the Balearic Islands of 923 different species with 87% of georeferenced records collected between 1830 and 2022. In addition, each record has associated information such as the sampling location (89%), collector and person who identified the species (64%), date of the capture (54%) and plant species where the bees were captured (20%). We believe that this database is the starting point to better understand and conserve bee biodiversity in the Iberian Peninsula.

Enhancing the diversity of mass-flowering crops (i.e. crop diversity) in agricultural landscapes is often proposed as a measure to favour pollinators and pollination, but it is uncertain whether crop diversity enhances pollinator richness on the wide landscape level. Here, we surveyed pollinator communities in semi-natural habitats and mass-flowering crops throughout the whole growing season in 26 agricultural landscapes to examine how the temporal and spatial heterogeneity in semi-natural habitats and crop diversity support pollinator species richness. Crop diversity was unrelated to pollinator richness in the wider landscape, and temporal and spatial heterogeneity in semi-natural habitats were equally important in determining pollinator richness. Surprisingly, the crop pollinator species pool size was a fixed proportion of the landscape pollinator species pool along a 0%–72% semi-natural habitat cover gradient. Synthesis and applications. Our results suggest that increasing crop diversity alone does not contribute to maintaining diverse wild pollinator communities in agricultural landscapes and emphasize the key role of temporally stable habitats such as semi-natural habitats to maintain rich pollinator communities.

Agri-Environmental Schemes (AES) have been proposed to mitigate the impact of agriculture on both taxonomic and functional biodiversity. However, a better knowledge of the mechanisms involved in the loss of agrobiodiversity is needed to implement efficient AES. An unbalanced effort on research towards arable lands compared to permanent crops, and on fauna relative to plants, is patent, which limits the generalization of AES effectiveness. We evaluated the effects of agricultural management and landscape simplification on taxonomic and functional diversity of the ground herb cover of 40 olive groves. We use a recently developed approach based on Hill numbers (rare, common and dominant species based) to analyse taxonomic and functional dissimilarity between farms with contrasting agricultural practices, and its potential attenuation by landscape complexity. We further explore the filtering effect of agricultural intensification on functional traits, and the relationship between functional and species richness across landscapes. We found that taxonomic and functional dissimilarity of herb assemblages between intensively and low-intensively managed fields was mainly due to rare species. Dissimilarity decreased as landscape complexity increased, evidencing that complex landscapes attenuate the impact of agriculture intensification on herb assemblage composition. Agricultural intensification favoured more functionally homogeneous assemblages and disfavoured the herbs pollinated by insects, while it did not seem to affect wind-pollinated species. Overall, functional richness increased exponentially with species richness across landscapes, but the latter was insufficient to drive any clear enhancement in functional richness in simple landscapes. In contrast, high species richness accelerated the enhancement in functional richness in intermediate and complex landscapes. These results highlight the functional filtering that intensive agriculture has generated for decades in h

Farming impacts animal-mediated seed dispersal through mechanisms operating on at least two spatial scales. First, at the landscape scale, through habitat loss and land conversion to agriculture/livestock grazing, and second, at the farm scale, via a local intensification of agricultural practices. These two scales of farming impact seed dispersal function but have rarely been integrated. In particular, studies evaluating the effect of agriculture on the seed dispersal function of frugivorous birds in Mediterranean ecosystems are lacking. This study evaluates the role of landscape transformation, from fruit-rich woodland habitats to olive grove landscapes, together with local intensive practices of soil management on the persistence of the seed dispersal function for Mediterranean fleshy-fruited plants in olive landscapes of south Spain. We used bird censuses, mist-nets, and seed traps to characterize avian frugivore assemblages, frugivory, and seed deposition in the seminatural woodland habitat (SNWH) patches and olive fields of 40 olives farms spanning 20 localities distributed across the whole range of olive cultivation in Andalusia (southern Spain). We found that despite the remarkable dispersal function of olive grove landscapes, avian frugivore abundance and diversity, frugivory, and seed arrival decreased in olive fields compared to SNWH patches. Likewise, SNWH cover loss and/or olive growing expansion decreased avian frugivory and seed arrival. Interestingly, the habitat effects in the olive farms often depended on the landscape context. In particular, less diverse fruit-eating bird assemblages pooled in SNWH patches as olive grove cover increased or SNWH decreased in the landscape, while remaining relatively invariant in the olive fields. Finally, compared to conventional intensive agriculture, low-intensity management increased frugivory and seed deposition. We conclude that olive fields are less permeable to frugivores than expected due to the agroforest

We investigated taxonomic and functional beta diversity of bird communities inhabiting Mediterranean olive groves subject to either intensive or low-intensity management of the ground cover and located in landscapes with different degrees of complexity. Location: Andalusia, southern Spain. Methods: We partitioned taxonomic and functional beta diversity into its two additive components, turnover and nestedness. We also explored the contributions of single sites to overall beta diversity (LCBD) and separated the effects of species replacement (turnover) and richness difference (nestedness) in order to identify ecologically unique sites—keystone communities—within the metacommunity. In a further step, we employed abundance-and functional-based indicator species analyses to characterize bird assemblages. Results: Taxonomic beta diversity increased with landscape complexity. Although both taxonomic and functional differences among assemblages were driven mainly by species replacement (regardless of management or landscape type), the contribution of trait replacement to the total functional beta diversity was much lower, suggesting that species performing similar functions replace each other between sites. There were no differences in LCBD between management types or categories of landscape complexity, but the contributions of sites to beta diversity decreased as the percentage cover of olive groves increased. Species richness was also important in explaining variation in LCBD as species-poor sites tended to contribute the most to the local-to- regional beta diversity. However, some farms displayed high values of LCBD due to the existence of a high replacement component, indicating that some species recorded in these sites were scarce elsewhere. The indicator species analyses of biodiversity in this agro-forestry system. Main conclusions: Our results show that agricultural expansion promotes biotic homogenization and exemplify how the identification of both keystone speci

One of the current challenges for applied ecologists is to understand how to manage/restore agroecosystems in a sustainable and cost-effective way. The intermediate landscape complexity hypothesis (ILCH) predicts that the effectiveness of agri-environmental measures (AES) on biodiversity and ecosystem services recovery is often largest in landscapes of intermediate complexity. This hypothesis has rarely been tested in savanna-like permanent agroecosystems. Focusing on pollinators, we test the ILCH at the regional scale in Mediterranean olive orchards, one of the most important permanent agroecosystems in the world. We inferred abundance of cavity-nesting pollinators in 40 paired olive orchards (extensively vs. intensively managed herbaceous cover) in 20 localities selected across a landscape complexity gradient. We also studied how different magnitudes in local management switches may affect pollinators by considering organic and intensive fields as management extremes in olive orchards. We used 208 trap nests for solitary bees to measure colonization rates. Additionally, we conducted pollinator surveys to ascertain that colonization rate was a representative proxy for pollinator activity. Our results showed that (a) changes in colonization rates due to local herb cover management peaked at intermediate landscape complexity, with extensively managed fields rendering higher colonization rates. (b) Organic fields had higher colonization rates than their control farms regardless of landscape complexity. (c) There was a highly significant correlation between nest colonization rates and density of pollinators foraging on flowers, which suggests that colonization rate is a good estimator of pollinator activity. Policy implications. The maintenance of ground herb cover (main agri-environmental measure in olive orchards) is a cost-effective investment allowing recuperation of pollinators when targeting olive farms located in landscapes of intermediate complexity. Additional