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Simple Summary: Improving floral margins around crops can help to maintain and conserve populations of wild pollinators, mainly insects, in agroecosystems, and can improve the ecosystem services they provide, such as pollination of many crops and wild plants. Some crops, such as melon, depend on insects for reproduction, which is why they are at risk, as pollination services are declining. Our study shows that the implementation of margins around melon crops showed a positive effect on the abundance and richness of pollinating insects in general, which was stronger in the second year after establishment. Specifically, managed shrubby margins favored the populations of Syrphidae, Andrenidae, Apidae (excl. Apis mellifera), and other pollinator groups, and bee richness, suggesting that this type of margin increases pollinators' activity to a greater extent than the other two types of margins (managed and unmanaged herbaceous margins). However, the type of margin did not show any added advantages for melon yield. Melon is among the most consumed fruits in the world, being a crop that depends almost entirely on insects for its reproduction, which is why it is especially sensitive to declining pollination services. Restoration and maintenance of hedgerows and agricultural borders around crops are generally carried out by sowing flowering herbaceous plants or establishing shrubby species; however, a cost-effective and lower-maintenance alternative for farmers could be as simple as allowing vegetation to regenerate naturally without any management actions. This work aimed to test the effects of three different types of margins (managed herbaceous, managed shrubby, and unmanaged herbaceous) on the overall abundance and richness of wild pollinators in melon crops. The work was performed in three localities in southern Spain over two years. Pollinators were monitored visually using 1 × 1 m sampling squares and pan traps within melon fields. Moreover, crop yield was estimated by measuring fruit weight and the number of seeds. In general, higher abundances of pollinators were observed in melon fields during the second year. In addition, the abundances of Syrphidae, Andrenidae, Apidae (excl. Apis mellifera), and pollinators other than bees, belonging to the orders Diptera, Coleoptera, Hymenoptera, and Lepidoptera, showed higher values in melon fields with shrubby margins than in fields with herbaceous margins (managed or unmanaged). However, no effect of floral margins on the yield of melon crops was found. [ABSTRACT FROM AUTHOR]

Farmland ecosystem services frequently result from different ecological functions simultaneous provided by specific biodiversity groups such as birds. These bundles of ecosystem services may be approached from inter-specific interaction networks, which inform about the structure of interactions while identifying the species more relevant for combining ecosystem services. Here, we studied how birds provide pest control in apple orchards, and seed dispersal in orchard-adjacent hedgerows and forests. For this, we used field data and DNA-metabarcoding of bird fecal samples, obtained across a whole year from three orchards in northern Spain, to build interaction networks between birds and arthropod apple pests, and between birds and non-crop fleshy-fruited plants. We addressed the structure of the different networks underpinning pest control and seed dispersal. We also combined both ecosystem services through a hybrid network to assess, by means of centrality measures, the topological roles of individual bird species and their ecological determinants. Interaction networks differed in structure, with pest-control network showing higher modularity and specialization than seed-dispersal network, otherwise characterized by high nestedness. These differences emerged from the different typologies, i.e. antagonistic vs. mutualistic, of the bird-pest and bird-plant interactions. The hybrid network integrating pest control and seed dispersal evidenced strong variability across birds in their role to connect ecosystem services, depending on their central or peripheral positions. Bird centrality was positively related with species abundance and independent of body size or diet diversity. This finding suggests the relevance of neutral processes (i.e. the random encounters of organisms) for driving inter-specific interactions, and it highlights the relevance of common birds for sustaining ecosystem service bundles in agroecosystems. The preservation of fruit-rich hedgerows and forest patches around apple orchards is an action recommended to maintain the populations of common bird species, responsible of both agricultural pest control and the natural regeneration of these habitats. • Interactions networks inform about pest control and seed dispersal in apple orchards. • Bird-pest network was highly modular whereas bird-plant network was highly nested. • Pest control and seed dispersal connected through bird species in a hybrid network. • Role of bird species for combining ecosystem services depends on relative abundance.. [ABSTRACT FROM AUTHOR]

Mass-flowering crops (MFCs) and beekeeping are increasing across agroecosystems globally. Managed honeybees could spillover after the blooming of MFCs into nearby natural habitats, especially if hive numbers are associated with the cover of MFCs at the landscape scale. Nevertheless, this phenomenon has been largely overlooked despite the potential impacts of honeybees on local wildlife. We assessed this ‘MFC-beekeeping’ association and honeybee spillover into woodland patches in 17 fragmented landscapes in SW Spain with contrasting cover of orange groves as MFC. Hive densities were almost four times greater in landscapes with high cover of orange groves and, after the orange-tree bloom, mean honeybee densities were eight times higher in woodland patches within these landscapes, as compared to landscapes with no/low cover. Seemingly, this spillover was resource-mediated since it mirrored the temporal changes in flower cover at habitat and landscape scales. Our study demonstrates for the first time a consistent spillover of managed honeybees from a MFC into nearby natural habitats. These findings are a warning about the potential detrimental effects of magnified honeybee densities on local fauna and flora, especially on wild bees. [ABSTRACT FROM AUTHOR]

• This work aims to compare the effects of three types of floral margins (managed herbaceous, managed shrubby, and unmanaged herbaceous) on the abundance and diversity of bees in order to propose a management strategy for the conservation of pollinating insects. • Managed margins supported higher abundances and richness than unmanaged ones, and specifically, supported at least 30% more rare bee genera than unmanaged margins. • Here we highlight the importance of floral margins management for the enhancement and conservation of bee communities, restoring habitat and food resources for pollinators across the Mediterranean agricultural landscape. Floral resources on crop field margins are a well-accepted measure to increase bee abundance in agricultural landscapes. However, studies have mainly focused on managed margins, while studies on the effect of unmanaged floral margins for the conservation of bees are still scarce. This work aims to test and compare the effects of three types of floral margins (managed herbaceous, managed shrubby, and unmanaged herbaceous) on the abundance and diversity of bees in order to propose a management strategy for the conservation of pollinating insects. Bee abundance was recorded by visual samplings in plots of 2 × 2 square meters over two years in the three margin types in four localities in southern Spain. The diversity of plant species and the flowers they supported were measured to explain the associated bee communities. Differences in the relative abundances of bee families and the number and abundance of bee genera were observed between margin types. Andrenidae was generally more abundant in the herbaceous margins regardless of whether these were managed or not. With the exception of the Halictidae, the majority of bees families (wild Apidae, Apis mellifera , Colletidae and Megachilidae) were more abundant in the managed than unmanaged margins. Moreover, the number of bee genera was higher in managed than in unmanaged margins. In addition, here we show that managed margins supported at least 30% more rare bee genera than unmanaged margins, highlighting the importance of floral margins management for the enhancement and conservation of bee communities, restoring habitat and food resources for pollinators across the Mediterranean agricultural landscape. [ABSTRACT FROM AUTHOR]

The strength of the behavioural processes associated with competitor coexistence may vary when different physical environments, and their biotic communities, come into contact, although empirical evidence of how interference varies across gradients of environmental complexity is still scarce in vertebrates. Here, I analyse how behavioural interactions and habitat selection regulate the local distribution of steppeland larks (Alaudidae) in a gradient from simple to heterogeneous agricultural landscapes in Spain, using crested lark Galerida cristata and Thekla lark G. theklae as study models. Galerida larks significantly partitioned by habitat but frequently co-occurred in heterogeneous environments. Irrespective of habitat divergence, however, the local densities of the two larks were negatively correlated, and the mechanisms beyond this pattern were investigated by means of playback experiments. When simulating the intrusion of the congener by broadcasting the species territorial calls, both larks responded with an aggressive response as intense with respect to warning and approach behaviour as when responding to the intrusion of a conspecific. However, birds promptly responded to playbacks only when congener territories were nearby, a phenomenon that points to learning as the mechanisms through which individuals finely tune their aggressive responses to the local competition levels. Heterospecifics occurred in closer proximity in diverse agro-ecosystems, possibly because of more abundant or diverse resources, and here engage in antagonistic interactions. The drop of species diversity associated with agricultural homogenisation is therefore likely to also bring about the disappearance of the behavioural repertoires associated with species interactions. [ABSTRACT FROM AUTHOR]

Because of its potential role in providing ecosystem services and private benefits (food security), the concern about the loss of agrobiodiversity has grown. We explore the links between agrobiodiversity and farm financial benefits in small-scale agroecosystems. We measured crop diversity in a subsistence-oriented agricultural production system: home gardens (n = 250) in the Iberian Peninsula. We calculated the imputed market value of home gardens' edible crops and estimated the association between agrobiodiversity and home gardens' gross financial value. Temperate home gardens harbor levels of agrobiodiversity comparable to those of tropical home gardens. Data suggest that an increase in crop diversity is associated with an increase in the gross financial value generated by home gardens. Our findings suggest that in non-commercially oriented agricultural systems, there is a positive link between agrobiodiversity and financial benefits, highlighting the contribution of agrobiodiversity to the provision of private benefits. [ABSTRACT FROM AUTHOR]

Abstract: Water performs essential ecological functions in agroecosystems and supplies an array of hydrologic ecosystem services (HES). The nature and quantity of HES is intimately linked with the management of the territory, and the capacity of the different land uses to partition rainfall into green (evapotranspiration) and blue (runoff) freshwater flows. This paper presents an innovative method to empirically assess the underlying relationship between the use and management of Mediterranean agroecosystems, their spatial pattern of green and blue freshwater flow generation and the provision of HES. We test this approach in Sierra Norte de Sevilla, a characteristic Spanish agro-forestry system. To assess the hydrological functioning we used the spatially explicit hydrologic model BalanceMED. HES’ identification and societal valuation was done through an expert panel. The hydrologic performance and the social values ascribed to the different services were combined to identify key provisioning areas or HES hotspots. Our results show that multifunctional agroecosystems, where agrarian and forestry activities co-exist, optimize the partition and use of freshwater flows and supply the largest bundles of HES at a wide range of spatial scales. The often low profitability of these extensive activities is prompting either the intensification or the abandonment of many Mediterranean agro ecosystems. We discuss the trade-offs in HES associated with these land use trends, and we illustrate the potential options available for implementing payments for ecosystem services (PES) schemes to pursue “win–win” management solutions. [Copyright &y& Elsevier]

Interest in ecosystem services provided by agroecosystems has grown over the last decades with research focusing on the type of environmental, economic and social benefits delivered by agroecosystems. Researchers suggest that, besides the provisioning of food, fuel, and fiber, agroecosystems provide habitat, cultural, and regulating services. One type of agroecosystem that remains relatively unexplored from an ecosystem service perspective is home gardens. In this paper, we aim at advancing the understanding of the value of home gardens by conducting an assessment of home gardens ecosystem services. For the empirical analysis we use home gardens in Vall Fosca (Catalan Pyrenees). We identify and characterize the most important ecosystem services provided by home gardens, and conduct a valuation of the social importance of home garden ecosystem services. The methodological approach for this work included an in-depth literature review, participant observation, semi-structured interviews, a valuation questionnaire, and a scientific panel consultation. We identified and characterized 19 ecosystem functions and related services. According to our informants, home gardens provide a large set of ecosystem services, being cultural services the category most valued. We found that the most important ecosystem services provided by home gardens differ from those provided by other types of agroecosystems. [Copyright &y& Elsevier]

Sewage sludge used as agricultural fertilizer has been identified as an important source of microplastics (MPs) to the environment. However, the fate of MPs added to agricultural soils is largely unknown. This study investigated the fate of MPs in agricultural soils amended with sewage sludge and the role of surface water runoff as a mechanism driving their transfer to aquatic ecosystems. This was assessed using three experimental plots located in a semi-arid area of Central Spain, which were planted with barley. The experimental plots received the following treatments: (1) control or no sludge application; (2) historical sludge application, five years prior to the experiment; and (3) sludge application at the beginning of the experiment. MPs were analyzed in surface water runoff and in different soil layers to investigate transport and infiltration for one year. The sewage sludge used in our experiment contained 5972–7771 MPs/kg dw. Based on this, we estimated that about 16,000 MPs were added to the agricultural plot amended with sludge. As expected, the sludge application significantly increased the MP concentration in soils. The control plot contained low MP concentrations (31–120 MPs kg−1 dw), potentially originating from atmospheric deposition. The plot treated five years prior to the experiment contained 226–412 and 177–235 MPs kg−1 dw at the start and end of the experiment, respectively; while the recently treated plot contained 182–231 and 138–288 MPs kg−1 dw. Our study shows that MP concentrations remain relatively constant in agricultural soils and that the MP infiltration capacity is very low. Surface water runoff had a negligible influence on the export of MPs from agricultural soils, mobilizing only 0.2–0.4% of the MPs added with sludge. We conclude that, in semi-arid regions, agricultural soils can be considered as long-term accumulators of MPs. [Display omitted] • Sewage sludge increases the concentration of microplastics in agricultural soils. • Microplastic concentrations remain relatively constant over time. • Microplastic infiltration to deeper soil horizons is very low. • Only about 0.2–0.4% of microplastics are mobilized by water runoff in one year. • The impacts of microplastic build-up on soil ecosystems should be further investigated. [ABSTRACT FROM AUTHOR]

Over two million commercial bumblebee colonies are used on an annual basis to pollinate around 20 crop types worldwide. Despite their use, especially with crops grown in greenhouses, there is mounting evidence that many individuals also forage outside of them. Hence, the use of commercial bumblebees poses a risk to wild pollinators, especially to those who share floral resources and pathogens. To date, however, there is little evidence about the impact of commercial bumblebees on pollinator communities in Europe. We surveyed the abundance of commercial Bombus terrestris and the prevalence of four of its parasites in natural areas at increasing distances from vegetable crops in Cabo de Gata-Níjar (Almería, SE Spain), the most extensive greenhouse cultivation area in the world. We also estimated resource niche overlap (i.e., shared plants used) between commercial bumblebees and the native pollinator community. Finally, we explored whether the abundance and diversity of pollinators in natural habitats were influenced by agricultural expansion (i.e., distance to greenhouses) and bumblebee abundance. We found a sharp reduction in commercial bumblebee densities at increasing distances from greenhouses, with most bumblebees (95%) foraging within a radius of less than 200 m from them. However, these commercial bumblebees had high parasite prevalence (41% of individuals infected) of trypanosomatids, microsporidians and neogregarines. Moreover, their diet particularly overlapped with honeybees and large wild bees. Yet, pollinator density and diversity were not related to the distance from greenhouses or to bumblebee abundance. Although our results suggest that commercial bumblebees do not significantly harm wild pollinators, actions like preventing their escape from greenhouses, monitoring their health and optimising their use should be considered so as to minimise future risks. • Commercial bumblebee densities decreased markedly at increasing distances from greenhouses. • These bumblebees had high parasite prevalence. • The diet of bumblebees particularly overlapped with honeybees and large wild bees. • Wild pollinator density and diversity were not related to bumblebee abundance. [ABSTRACT FROM AUTHOR]

(1) Intensive agriculture has a high impact on pollinating insects, and conservation strategies targeting agricultural landscapes may greatly contribute to their maintenance. The aim of this work was to quantify the effect that the vegetation of crop margins, with either herbaceous or shrubby plants, had on the abundance and diversity of bees in comparison to non-restored margins. (2) The work was carried out in an area of intensive agriculture in southern Spain. Bees were monitored visually and using pan traps, and floral resources were quantified in crop margins for two years. (3) An increase in the abundance and diversity of wild bees in restored margins was registered, compared to non-restored margins. Significant differences in the structure of bee communities were found between shrubby and herbaceous margins. Apis mellifera and mining bees were found to be more polylectic than wild Apidae and Megachilidae. The abundance of A. mellifera and mining bees was correlated to the total floral resources, in particular, to those offered by the Boraginaceae and Brassicaceae; wild Apidae and Megachilidae were associated with the Lamiaceae. (4) This work emphasises the importance of floral diversity and shrubby plants for the maintenance of rich bee communities in Mediterranean agricultural landscapes. [ABSTRACT FROM AUTHOR]

Land use at landscape and field scales can increase the diversity and abundance of natural enemies for pest control. In this study, we investigated interactions between landscape elements (semi-natural vegetation, olive orchards, vineyards, other agricultural areas) and inter-row management (vegetation cover vs. bare soil) in relation to arthropod populations in Andalusian vineyards. Arthropods were collected from grapevine foliage in 15 vineyards using suction sampling. Landscape structure was analyzed within a 750 m radius surrounding the studied vineyards. Arthropods were categorized into functional groups (predators, parasitoids, herbivores), and their responses to the most influencing factors were analyzed by likelihood methods and model selection. Of the total of 650 arthropods collected, 48% were predators, 33% herbivores and 19% parasitoids. Numbers of predatory aeolothrips, parasitoids and herbivorous cicadas in the study vineyards decreased with an increased proportion of vineyards in the surroundings. Spider populations in vineyards increased with increasing proportions of other agricultural fields (non-flowering crops) in the surroundings. Semi-natural elements and olive orchards had no influence on the abundance of collected arthropods. We observed synergistic effects between landscape elements and inter-row management. The total numbers of arthropods, herbivores and parasitoids in vineyards benefitted from inter-row vegetation, while spiders benefitted from bare soil. Our findings underline the importance of both surrounding landscape elements and vineyard ground cover management to promote beneficial arthropods for potential natural pest control. [ABSTRACT FROM AUTHOR]