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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 homogeneous olive-dominated landscapes. Synthesis and applications. Herb cover is essential to support the fauna of permanent croplands and their sustainable production. Hence, Agri-Environmental Schemes (AES) in these croplands should promote management practices favouring the diversity and functionality of herb assemblages. Such AES should be particularly prioritized in homogeneous landscapes, where ground herb cover composition and function has long been homogenized to a great extent.

Anthropogenic‐driven perturbations such as agricultural intensification can affect simultaneously and distinctly several species groups and ecosystem functions. Unveiling these concurrent effects on interdependent species groups connected by different types of ecological interactions is a key challenge for ecologists. To this endeavour, hybrid ecological networks arise as a promising tool. In this study, we used bee trap nests to sample hybrid networks that combined mutualistic and antagonistic interactions to explore agricultural intensification effects on the representation of network motifs (i.e. subnetworks showing different interaction types between a small number of species). Also, we assessed the variability of network motif's frequencies on farms under similar management regimes and the dissimilarity between farms under different ones. For this, we implemented a novel approach, calculating network functional spaces based on probability density estimates of network motif's frequencies, using network motifs as traits. Results showed that environmentally friendly practices maximize the representation of mutualistic (cavity nesting bees–plants) and predation (wasps–prey and bees/wasps–antagonists) motifs. In contrast, intensive agriculture favoured generalist and intraguild predation interactions. Lastly, the frequency of motifs representing antagonistic interactions was more inconsistent and unpredictable across sites than mutualistic motifs, especially on intensified farms. Our novel approach, dissecting hybrid networks into their motifs and analysing the functional space defined by these, reported detailed and contrasting effects of agricultural intensification on network motifs that represent the mutualistic and antagonistic interactions in this system. A free plain language summary can be found within the Supporting Information of this article.

The mechanism(s) that generate measurement error matter to inference. Survey measurement error is typically thought to represent simple misreporting correctable through improved measurement. But errors might also or alternatively reflect respondent misperceptions that materially affect the respondent decisions under study. We show analytically that these alternate data generating processes imply different appropriate regression specifications and have distinct effects on the bias in parameter estimates. We introduce a simple empirical technique to generate unbiased estimates under more general conditions and to apportion measurement error between misreporting and misperceptions in measurement error when one has both self-reported and objectively-measured observations of the same explanatory variable. We then apply these techniques to the longstanding question of agricultural intensification: do farmers increase input application rates per unit area as the size of the plots they cultivate decreases? Using nationally representative data from four sub-Saharan African countries, we find strong evidence that measurement error in plot size reflects a mixture of farmer misreporting and misperceptions. The results matter to inference around the intensification hypothesis and call into question whether more objective, precise measures are always preferable when estimating behavioral parameters.

Los autores de la UAM pertenecen al Terrestrial Ecology Group (TEG), Agricultural intensification is one of the main drivers of species loss worldwide, but there is still a lack of information about its effect on functional diversity of arable weed communities. Using a large-scale pan European study including 786 fields within 261 farms from eight countries, we analysed differences in the taxonomic and functional diversity of arable weeds assemblages across different levels of agricultural intensification. We estimated weed species frequency in each field, and collected species' traits (vegetative height, SLA and seed mass) from the TRY plant trait database. With this information, we estimated taxonomic (species richness), functional composition (community weighted means) and functional diversity (functional richness, evenness, divergence and redundancy). We used indicators of agricultural management intensity at the individual field scale (e.g. yield, inputs of nitrogen fertilizer and herbicides, frequency of mechanical weed control practices) and at the landscape scale surrounding the field (i.e. number of crop types, mean field size and proportion of arable land cover within a radius of 500 m from the sampling points). The effects of agricultural intensification on species and functional richness at the field scale were stronger than those of intensification at the landscape scale, and we did not observe evidence of interacting effects between the two scales. Overall, assemblages in more intensified areas had fewer species, a higher prevalence of species with ruderal strategies (low stature, high leaf area, light seeds), and lower functional redundancy. Maintaining the diversity of Europe's arable weed communities requires some simple management interventions, for example, reducing the high intensity of field-level agricultural management across Europe, which could be complemented by interventions that increase landscape complexity. A free Plain Language Summary can be found within the Supporting Information of this article

Within ecological communities, species engage in myriad interaction types, yet empirical examples of hybrid species interaction networks composed of multiple types of interactions are still scarce. A key knowledge gap is understanding how the structure and stability of such hybrid networks are affected by anthropogenic disturbance. Using 15,169 interaction observations, we constructed 16 hybrid herbivore-plant-pollinator networks along an agricultural intensification gradient to explore changes in network structure and robustness to local extinctions. We found that agricultural intensification led to declines in modularity but increases in nestedness and connectance. Notably, network connectance, a structural feature typically thought to increase robustness, caused declines in hybrid network robustness, but the directionality of changes in robustness along the gradient depended on the order of local species extinctions. Our results not only demonstrate the impacts of anthropogenic disturbance on hybrid network structure, but they also provide unexpected insights into the structure-stability relationship of hybrid networks.

The central tenet of European farmland ecology is that agricultural intensification during the 20th century was largely responsible for dramatic declines in species abundances. However, during this time, human rural settlements were also undergoing radical changes through modernization, with undocumented biodiversity impacts in this important wildlife habitat. We performed the first ever large‐scale study to disentangle the impact of these simultaneous processes on farmland bird diversity in 104 Polish villages. We show that modernized villages and their surrounding agricultural fields had 50–60% fewer birds than those in and around comparable older villages. The relative contribution of modernization versus agricultural intensification to predicted bird declines was 88% versus 12% for bird communities in villages and 56% versus 44% in surrounding croplands, with considerable variation among ecological species subgroups. These results challenge our current understanding of agricultural ecosystem ecology and how best to implement conservation measures costing billions of euros annually.

In seasonal environments, increasing spring temperatures lead many taxa to advance the timing of reproduction. Species that do not may suffer lower fitness. We investigated why black-tailed godwits (Limosa limosa limosa), a ground-breeding agricultural grassland shorebird, have not advanced timing of reproduction during the last three decades in the face of climate change and human-induced habitat degradation. We used data from an 11-year field study to parameterize an Integral Projection Model to predict how spring temperature and habitat quality simultaneously influence the timing of reproduction and population dynamics. We found apparent selection for earlier laying, but not a correlation between the laying dates of parents and their offspring. Nevertheless, in warmer springs, laying dates of adults show a stronger positive correlation with laying date in previous springs than in cooler ones, and this leads us to predict a slight advance in the timing of reproduction if spring temperatures continue to increase. We also show that only in landscapes with low agricultural activity, the population can continue to act as a source. This study shows how climate change and declining habitat quality may enhance extinction risk.

Farmland birds are among the most threatened bird species in Europe, largely as a result of agricultural intensification which has driven widespread biodiversity losses. Breeding waders associated with grassland and arable habitats are particularly vulnerable and a frequent focus of agri‐environment schemes (AES) designed to halt and reverse population declines. We review existing literature, providing a quantitative assessment of the effectiveness of policy and management interventions used throughout Europe to improve population and demographic metrics of grassland‐breeding waders. Targeted AES and site protection measures were more likely to be effective than less targeted AES and were ten times more likely to be effective than would be expected by chance, particularly for population trend and productivity metrics. Positive effects of AES and site protection did not appear synergistic. Management interventions which had the greatest chance of increasing population growth or productivity included modification of mowing regimes, increasing wet conditions, and the use of nest protection. Success rates varied according to the species and metric being evaluated. None of the policy or management interventions we evaluated were associated with a significant risk of negative impacts on breeding waders. Our findings support the use of agri‐environment schemes, site protection, and management measures for grassland‐breeding wader conservation in Europe. Due to publication bias, our findings are most applicable to intensively managed agricultural landscapes. More studies are needed to identify measures that increase chick survival. Despite broadly effective conservation measures already in use, grassland‐breeding waders in Europe continue to decline. More research is needed to improve the likelihood and magnitude of positive outcomes, coupled with wider implementation of effective measures to substantially increase favorable land management for these species.

Agri‐environment schemes (AES) are the main policy mechanism available for reversing the widespread declines of European farmland biodiversity. We assessed the impact of AES land management on the abundance of bird species whose populations have declined as a consequence of agricultural intensification. The AES involved the deployment of a whole‐farm package of wildlife‐friendly land management options covering an average of 7% of the farmed area. The study was conducted across three English regions and focused on species of conservation concern and on a wider suite of farmland birds comprising the UK Government's Farmland Bird Indicator (FBI). Changes in avian abundance on AES farms were compared with those measured across the wider farmed landscape as part of a national bird monitoring scheme. Twelve out of 17 priority species, and the FBI, showed more positive changes in abundance on AES farms in at least one region. Eight species exhibited sustained responses to AES management in at least one region, and eight species exhibited a temporary enhancement in abundance in at least one region. Temporary responses to AES management followed a large scale failure of key AES options to establish during successive wet and cold summers, and involved species known to depend on the habitats provided by these options. In order to offset ongoing declines of FBI species in the wider farmed countryside of 2.3–4.1% per annum, we estimate 26–33% of FBI populations would need to be subject to AES‐type management. This study demonstrates the potential for AES land management to substantially enhance the abundance of priority farmland birds and highlights the need for option packages that are resilient to the impacts of variable weather conditions.

This article uses panel data from the Living Standards Measurement Study-Integrated Surveys on Agriculture for Uganda to assess the farm-level effects of nonfarm employment on agricultural intensification and productivity change. A sample selection model is used to account for both unobserved heterogeneity and potential simultaneity between agricultural production and nonfarm income. Results show that nonfarm employment can have differential impacts on farm technology intensity and productivity. Nonfarm income is found to have a positive impact on farm hired labor and improved seed intensity; a negative effect on on-farm family labor use; and no significant impact on fertilizer, soil water management, and joint use of farm technologies. The econometric evidence also indicates that agricultural productivity declines as nonfarm income increases. Taken together, our findings reveal important trade-offs between nonfarm employment and income and farm productivity growth under smallholder agriculture. The results indicated that targeted policies are required to reduce these potential trade-offs between nonfarm employment and agricultural intensification and productivity change.

Intensification of land use and management over recent decades has resulted in trade-offs between food or timber production and other ecosystem services (ES). Despite an increase in scholarly publications on ES, the temporal aspects of ES trade-offs have largely been neglected to date. Here we explore how past and future land-use trajectories (pathways of change) influence ES over time, using mountain landscapes as a model. Based on a synthesis of 51 cases of temporal changes in ES within mountain landscapes, we analyze how changes in land-use intensity influence the supply of ten key services and we describe six typical examples (archetypes) of ES change. Our analysis reveals that land-use intensity is an important factor shaping these archetypes. Land-use intensification often degrades ES (eg recreation and water regulation), with the exception of services targeted by intensification (food or timber) and with differences between forest and agricultural intensification. Service degradation following intensification is not always reversed by reductions in land-use intensity (termed “extensification”).

Conservation interventions are being implemented at various spatial scales to reduce the impacts of rising global population and affluence on biodiversity and ecosystems. While the direct impacts of these conservation efforts are considered, the unintended consequences brought about by market feedback effects are often overlooked. Perverse market outcomes could result in reduced or even reversed net impacts of conservation efforts. We develop an economic framework to describe how the intended impacts of conservation interventions could be compromised due to unanticipated reactions to regulations in the market: policies aimed at restricting supply could potentially result in leakage effects through external or unregulated markets. Using this framework, we review how various intervention methods could result in negative feedback impacts on biodiversity, including legal restrictions like protected areas, market-based approaches, and agricultural intensification. Finally, we discuss how conservation management and planning can be designed to ensure the risks of perverse market outcomes are detected, if not overcome, and we address some knowledge gaps that affect our understanding of how market feedbacks vary across spatial and temporal scales, especially with teleconnectedness and increased international trade.

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator-dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes., The study was funded by the EU FP7 project “Status and Trends of European Pollinators” (244 090, www.STEP-project.net) and Biodiversa‐FACCE project “Enhancing biodiversity‐based ecosystem services to crops through optimised densities of green infrastructure in agricultural landscapes” (PCIN‐2014‐048, http://www.cec.lu.se/research/ecodeal). JPGV and MV acknowledge support from the Severo Ochoa Program for Centres of Excellence in R+D+I (SEV‐2012‐0262), and FLORMAS (CGL 2012‐33801). JBW, VJW, SGP and SPMR acknowledge the support of Insect Pollinators Initiative research funded jointly by a grant from BBSRC, Defra, NERC, the Scottish Government and the Wellcome Trust, under the Living with Environmental Change Partnership. HGS and RB were supported by the Swedish Research Council FORMAS. JS and DK were supported by the Dutch Ministry of Economic Affairs (BO‐11‐011.01‐011 and KB‐14‐003‐006), AH and ISD were supported by the DFG Collaborative Research Centre 1047 Insect timing, and ISD and MD through the 2013–2014 BiodivERsA/FACCE – JPI project Ecodeal with national funding from BMBF.

The recent trend of agricultural intensification in tropical landscapes poses a new threat to biodiversity conservation. Conversion of previously heterogeneous agricultural landscapes to intensive plantation agriculture simplifies and homogenizes the landscape, reducing availability, and connectivity of natural habitat for native species. To assess the impact of agricultural intensification on bats, we characterized the bat assemblage in the Sarapiqui region of Costa Rica, where heterogeneous land uses are being converted to intensive, large-scale pineapple plantations. In 2012 and 2013, we sampled bats in 20 remnant forest patches surrounded by varying proportions of pasture, mature forest, and pineapple and captured 1821 individual bats representing 39 species. We used ordination analyses to evaluate changes in species composition, where pineapple is the main component of the agricultural matrix. We identified landscape metrics specifically correlated with pineapple and used multiple linear regression to test their effects on bat species richness, diversity, and guild-specific relative abundance. Results suggest pineapple expansion is driving changes in assemblage composition in remnant forest patches, resulting in new assemblages with higher proportions of frugivorous bats and lower proportions of insectivorous bats than in continuous mature forests. In addition, while pineapple does not diminish total bat species richness and diversity, the reduced forest cover and increased distance between forest patches in pineapple plantations has a significant negative impact on the relative abundance of insectivores. We also identify a potential threshold effect whereby patches surrounded by more than 50 percent forest can retain assemblage composition similar to that found in continuous mature forest. Resumen La tendencia reciente de intensificacion agricola en paisajes tropicales presenta una amenaza nueva a la conservacion de biodiversidad. La conversion de paisajes agricolas que previamente estaban compuestos de usos de suelo diversos a plantaciones intensivos de grandes extensiones simplifica y homogeniza el paisaje, reduciendo la cantidad y conectividad de habitat disponible para especies nativas. Para evaluar el impacto de intensificacion de agricultura en murcielagos, caracterizamos la comunidad de murcielagos en Sarapiqui, Costa Rica, donde usos de suelo heterogeneos estan siendo convertidos a plantaciones intensivas y extensivas de pina. En 2012 y 2013 capturamos murcielagos en 20 parches de bosque remanente rodeados por proporciones diferentes de pasto, bosque maduro, y pina. Capturamos 1821 murcielagos, representando 39 especies. Utilizamos ordinacion para evaluar cambios en composicion de especies donde pina es el componente dominante del matriz. Identificamos metricos de composicion y configuracion del uso de suelo especificamente asociados con pina, y utilizamos regresion lineal para probar los efectos de estos metricos en la riqueza y diversidad de especies y la abundancia de cada gremio. Los resultados indican que la expansion de pina esta impulsando cambios en la composicion de la comunidad de murcielagos en parches del bosque remanente, produciendo comunidades con una proporcion de frugivoros mas alta y una proporcion de insectivoros mas baja que en bosque continuo. Ademas, aunque pina no disminuye la riqueza y diversidad total de especies, tiene un impacto negativo significante en la abundancia de insectivoros. Tambien identificamos un efecto de umbral por lo cual parcelas rodeadas por mas de 50% bosque pueden retener composicion parecida a lo que se encuentra en bosque continuo.

Summary 1. The magnitude of the benefits derived from organic farming within contrasting managed landscapes remains unclear and, in particular, the potential scale-dependent response of insect parasitoids is relatively unexplored. Identifying the scale at which parasitoids are affected by organic farming will be an important step to enhance their conservation. 2. We sampled tachinid parasitoids at the centre and margin of arable and grassland fields on paired organic and conventional farms located in landscapes with different proportions of organic land. A total of 192 fields were sampled in two biogeographical regions of the UK. 3. We found that the positive effect of organic farming on tachinid parasitoid diversity can be observed at multiple spatial scales. At the local scale, we found higher abundance and species richness of tachinid parasitoids on organic than on conventional farms and on field margins than on field centres. At the landscape scale, the diversity of tachinids was higher in landscapes with higher proportions of organic land. At both scales, the positive effect of organic farming was clear for arable fields, while it was almost neutral for grasslands. 4. Synthesis and applications. Any attempt to enhance parasitoid diversity in agricultural landscapes needs to consider the local management in relation to the habitat type, location within the field and agricultural management in the surrounding landscape. To restore parasitoid diversity, the promotion of organic agriculture should aim to increase both the total extent of organic farming and the connectivity of individual farms. As the benefits of organic farming to biodiversity clearly spread beyond individual farm boundaries, any assessment of organic farming should consider these positive externalities.

Modern farming practices threaten wildlife in different ways, and failure to identify the complexity of multiple threats acting in synergy may result in ineffective management. To protect ground-nesting birds in farmland, monitoring and mitigating impacts of mechanical harvesting is crucial. Here, we use 6 years of data from a nationwide volunteer-based monitoring scheme of the Montagu's harrier, a ground-nesting raptor, in French farmlands. We assess the effectiveness of alternative nest protection measures and map their potential benefit to the species. We show that unprotected nests in cultivated land are strongly negatively affected by harvesting and thus require active management. Further, we show that protection from harvesting alone (e.g. by leaving a small unharvested buffer around the nest) is impaired by post-harvest predation at nests that become highly conspicuous after harvest. Measures that simultaneously protect from harvesting and predation (by adding a fence around the nest) significantly enhance nest productivity. The map of expected gain from nest protection in relation to available volunteers' workforce pinpoints large areas of high expected gain from nest protection that are not matched by equally high workforce availability. This mismatch suggests that the impact of nest protection can be further improved by increasing volunteer efforts in key areas where they are low relative to the expected gain they could have. Synthesis and applications. This study shows that synergistic interplay of multiple factors (e.g. mechanical harvesting and predation) may completely undermine the success of well-intentioned conservation efforts. However, identifying areas where the greatest expected gains can be achieved relative to effort expended can minimize the risk of wasted volunteer actions. Overall, this study underscores the importance of citizen science for collecting large-scale data useful for producing science and ultimately informs large-scale evidence-based conservation actions within an adaptive management framework. This study shows that synergistic interplay of multiple factors (e.g. mechanical harvesting and predation) may completely undermine the success of well-intentioned conservation efforts. However, identifying areas where the greatest expected gains can be achieved relative to effort expended can minimize the risk of wasted volunteer actions. Overall, this study underscores the importance of citizen science for collecting large-scale data useful for producing science and ultimately informs large-scale evidence-based conservation actions within an adaptive management framework., A.S. was supported by the Finnish School in Wildlife Biology, Conservation and Management (LUOVA) and by the Kone Foundation.

In recent decades, landscape simplification due to agricultural intensification has resulted in biocontrol loss within agroecosystems leading to an increase in pest outbreaks. Empirical experiments have focused on the relationship between landscape pattern and the abundance of specific species. However, fewer studies have examined the varied responses of multiple natural enemy modules to landscape simplification. In the present study, 23 landscapes were examined to determine the effects of landscape simplification on cereal aphids and their natural enemies. Results showed that landscape simplification can increase cereal aphid populations with no significant effects on the total abundance of natural enemies. For each natural enemy module, it was found that the abundance of parasitic wasps was greatly increased by landscape simplification while the abundance of ground-dwelling predators was significantly reduced. In contrast, the abundance of leaf-dwelling predators was not significantly altered by landscape simplification. Therefore, the varied response of the three natural enemy modules to landscape simplification can result in major fluctuations in natural enemy–pest ratios and ultimately disrupt the top-down control of natural predators and biocontrol services within agroecosystems. In conclusion, quantitative food-web analysis could be a promising technique in clarifying the varied response of the three natural enemy modules to landscape pattern changes and species-specific abundance, a field of biological pest control that requires further study.

This study investigates temporal changes in dietary practices in the Caribbean archipelago during the Ceramic Age (400 BC–AD 1500), through analyses of dental wear and pathology. Some previous studies in the region have suggested that diet and subsistence practices changed over time due to increasing sociopolitical complexity, climate change, or adaptation to island environments rich in marine resources. Both horticultural/agricultural intensification and increased marine focus of the diet over time have been posited, based among other things on faunal and botanical remains, and early ethnohistorical accounts. Local and micro-regional stable isotope studies of temporal dietary variation have found few indications for change over time, and large regional isotope studies are still lacking. Dentitions from sites throughout the region dating to the Early Ceramic Age (400 BC–AD 600/800) and the Late Ceramic Age (AD 600/800–1500) were analysed in order to assess temporal differences. Intra-individual rates of wear were calculated using the difference in degree of wear between the adjacent molars and the two groups were compared with principal axis analysis. Caries, antemortem tooth loss, abscesses and dental calculus were recorded per individual and per tooth/socket, and population caries and antemortem tooth loss rates were assessed and compared by age group, tooth class and sex. Comparisons between the two occupation periods revealed significant differences in the rate of dental wear and pathology, indicating a shift in dietary practices over time, coinciding with known social changes. The increase in pathology rates suggests a rise in the consumption of cariogenic foods or preparation techniques that increase cariogenicity. The decrease in rate of wear over time indicates a reduction in abrasivity of the diet. Together these data suggest that there was a growing focus on refined, cariogenic foods, likely horticultural/agricultural produce. Copyright © 2014 John Wiley & Sons, Ltd.

Studies evaluating agri-environmental schemes (AES) usually focus on responses of single species or functional groups. Analyses are generally based on simple habitat measurements but ignore food availability and other important factors. This can limit our understanding of the ultimate causes determining the reactions of birds to AES. We investigated these issues in detail and throughout the main seasons of a bird's annual cycle (mating, postfledging and wintering) in a dry cereal farmland in a Special Protection Area for farmland birds in central Spain. First, we modeled four bird response parameters (abundance, species richness, diversity and "Species of European Conservation Concern" [SPEC]-score), using detailed food availability and vegetation structure measurements (food models). Second, we fitted new models, built using only substrate composition variables (habitat models). Whereas habitat models revealed that both, fields included and not included in the AES benefited birds, food models went a step further and included seed and arthropod biomass as important predictors, respectively, in winter and during the postfledging season. The validation process showed that food models were on average 13% better (up to 20% in some variables) in predicting bird responses. However, the cost of obtaining data for food models was five times higher than for habitat models. This novel approach highlighted the importance of food availability-related causal processes involved in bird responses to AES, which remained undetected when using conventional substrate composition assessment models. Despite their higher costs, measurements of food availability add important details to interpret the reactions of the bird community to AES interventions and thus facilitate evaluating the real efficiency of AES programs.

Although biological conservation has traditionally focused on the protection of pristine areas, it is becoming increasingly evident that efforts should also be made toward the maintenance of biological diversity in human-managed ecosystems. We evaluated the potential role of scattered, remnant trees in enhancing ant diversity in agricultural lands within a biodiversity hotspot, namely the Cerrado savannas of central Brazil. Ant collections were performed in, beneath, and away from the crowns of a native tree species growing in planted pastures, soy fields, and in small (

Agricultural intensification (AI) is a great threat to biodiversity and its negative effects on species richness of different communities have been repeatedly shown. The effects of AI on community composition and variability, however, are important for assessing the predictability of community responses, but have rarely been studied simultaneously and across different taxonomic groups. In this study, we focused on parasitoids (primary and secondary) and predators (hoverflies and carabid beetles) of aphids in winter wheat fields with contrasting AI regimes (low AI, i.e. organic fields in structurally complex landscapes vs. high AI, i.e. conventional fields in structurally simple landscapes). We found divergence in species composition of more specialised, low-dispersing primary and secondary parasitoids within high AI fields, probably due to the disruption of the exchanges of species between local populations in structurally simple landscapes. In contrast, species composition of less specialised, highly dispersing carabid beetles and hoverflies converged in fields with high AI, where they were characterised by the dominance of a single, vagile species adapted to high land-use conditions. Furthermore, temporal community shifts were only pronounced in primary parasitoids and hoverflies, with higher temporal changes in fields with high AI in primary parasitoids. Collectively, our results illustrate that environmental homogenisation due to AI does not necessarily induce spatio-temporal homogenisation of communities, but rather can have contrasting effects on more specialised, low-dispersive parasitoids versus more generalised, high-dispersive predators, thereby demonstrating great differences in the predictability of responses to AI among aphid natural enemies.

"This is the peer reviewed version of the following article: Functional Ecology 31.2 (2017): 427-435, which has been published in final form at https://doi.org/10.1111/1365-2435.12709. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions", Increasing land-use intensification is leading to biodiversity losses world-wide, which can reduce the functioning of ecosystems. However, it is increasingly clear that not all species are equally important for ecosystem processes: whereas the loss of a functionally unique species may reduce the capacity of the community to perform some functions, losing a functionally redundant species should have a much smaller impact. Assessing the vulnerability of functional diversity (FD) to species extinctions can help to predict the impacts of land-use intensification. This approach consists in ranking species according to their risk of extinction and then estimating the trajectory followed by FD as species are lost from local communities. However, the most widely used FD indices are not independent of species richness, being much more sensitive to the loss of species in species-poor than in species-rich sites. This may result in misleading interpretations, affecting our ability to rank communities according to the vulnerability of their FD to species loss, by confounding it with the initial level of species richness. Here, we propose comparing the trajectory of FD under the most plausible order of species loss with that followed under random species losses as an effective way to remove the trivial effect of species richness in the assessments of vulnerability to species loss. After decoupling vulnerability from species richness, we used it to analyse the effect of agricultural intensification on the vulnerability of arable plant communities in Mediterranean agricultural fields. Our results show that management strategies aiming to increase the functionality of these systems should focus on intermediately intensified fields, where small reductions in the level of intensification are likely to benefit arable plant diversity, increasing the number of species and FD and decreasing the vulnerability of FD to species losses. Removing the effect of species richness is essential to attain unbiased estimations of the vulnerability of communities to species loss, especially when species-poor communities are considered. Combining vulnerability with information on taxonomic and functional diversity appears as a promising tool to inform decision-making processes, anticipating the effects of local extinctions

Questions Do diversity components (α, β and γ) differ across contrasting regions? What is the relative contribution of organic and conventional farming practices to the structuring of arable weed species diversity and different functional groups (legumes, grasses and broad-leaves)? To what extent do arable weed communities differ between regions and farming systems (organic vs conventional)? Location Twenty-six farms in total in northeast Spain (Catalonia) and north Germany (Lower Saxony). Methods We examined the weed flora in paired organic and conventional farms at each locality and assessed diversity components by additive partitioning of species richness (α, β and γ). Results The weed species composition differed greatly between the two regions. Only 18 of 135 arable weed species were shared. The α-, β- and γ-diversity of all functional groups was significantly higher under organic farming practices for both regions, indicating an increasing homogenization of local communities by agricultural intensification within each region. β-diversity contributed most to the total observed species richness in both regions (69.8% and 35.8% on organic and conventional farms, respectively, in Catalonia; and 62.4% and 53.0% on organic and conventional farms, respectively, in Lower Saxony). These results demonstrate the great importance of environmental heterogeneity and of farm-specific differences in agricultural practices for the richness of arable weed species. Conclusions Regardless of the substantial differences in arable weed community composition across regions, our study emphasizes the great importance of organic farming for arable weed species richness. Understanding the patterns and causes of the dissimilarity of local communities appears to be a key factor for species conservation and the development of effective European-wide agri-environmental schemes at landscape and regional scales. This approach is in contrast to current nature conservation practices that are restricted primarily to local (field- and farm-scale) implementation.