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European farmland serves as a crucial habitat for many organisms, but the transition from extensive to intensive agriculture has led to a loss of biodiversity that also concerned farmland birds. Intensification has various aspects including landscape homogenisation, whereby large field blocks are created in once heterogeneous landscapes that traditionally consisted of small fields. However, some farmland specialists may indeed benefit from homogeneous landscapes, as they contain a greater share of preferred open habitats. To elucidate this paradox, we focused on a farmland specialist ground-nesting insectivorous bird, the Eurasian Skylark (Alauda arvensis), unravelling its abundance in different landscape structures. The contrasting landscape structures are found in a lowland region along the border between two countries: Slovakia with large fields and Austria with small fields. In this ''natural experiment'', bird censuses, food supply assessments, and vegetation structure analyses were carried out during the Skylark breeding season. Austria showed significantly higher local abundance of Skylark compared to Slovakia, which persisted whole season. The Skylark numbers were positively correlated with an increasing number of crop types. This positive effect of crop number was likely associated with higher food availability at sites with more crops, highlighting the role of diverse crop compositions in fostering a stable food supply for farmland birds. These results indicate that even open-habitat farmland specialists benefit from the landscape heterogeneity provided by small fields composed of different crops. Slovakia-Austria differences highlight the need for context-specific conservation that should also be a concern for agri-environmental measures within the EU’s Common Agricultural Policy.

Semi-natural habitats (SNHs) surrounding agricultural fields contribute significantly to biodiversity in agricultural landscapes. SNHs can be divided into large habitat patches such as contiguous patches of forests, and smaller, interspersed linear habitat types such as grassy field margins. Traditional small-holder agricultural farmlands in China, replete with rich linear habitats, are notably beneficial for biodiversity. However, as these farmlands undergo consolidation to enhance the efficiency of machinery, linear habitats are being removed, a process that could adversely affect biodiversity. Appropriate agri-environmental measures (AEM), such as the restoration of field margins via strategic planting, could serve as an effective countermeasure to maintain biodiversity in consolidated land. This paper discusses how biodiversity monitoring can aid in evaluating the impact of land consolidation and the efficacy of AEM in China, from species richness and species composition perspectives. The paper also discusses the function of linear habitats and how they interact with large habitat patches in promoting biodiversity, while noting that outcomes are likely to vary among taxa. Long-term, multiple-taxa and comprehensive assessments are recommended in further studies, and a collaborative approach that involves multiple stakeholders is essential to ensure a success implication of AEM in China.

Agricultural intensification reduces the taxonomic diversity of bird communities, but its influence on functional diversity has been less studied. Here, we analyze the response of functional diversity of different cereal farmland bird communities across Europe to a gradient of agricultural intensification. We collected bibliographical information on life history traits (i.e. body mass, brain size, age of sexual maturity, clutch size, number of clutches, lifespan) of 30 species of birds recorded during field surveys in eight European countries. The index ''brood value'' was calculated to know each species’ level of reproductive investment per clutch. Intensification gradients at two spatial scales were obtained from field data through PCA, related to management practices at the field scale and the variation in structure and composition of farmland at the landscape scale respectively. We calculated the functional diversity index (FD) and the community-weighted mean (CWM) for each trait and sampling area, and linear mixed models in relation to the two intensification gradients were performed. Results showed that stronger intensification at the field level favors the assembly of shorter-lived communities and bird species with smaller relative brain sizes, also decreasing overall trait diversity. It also restricts the range of strategies for parental investment, reducing the functional diversity of the brood value index. More intensive field management would favor bird communities dominated by generalist and even introduced and/or managed hunting species, while putting at risk those farmland- and grassland-adapted species, typically more associated with the provision of ecosystem services. This highlights the relevance of field management (agrochemicals use, ploughing frequency) for the functional composition of bird communities and the conservation of farmland biodiversity. These findings add to existing knowledge on how species’ pace of life and cognitive capacity interact with drivers of global change, such as agricultural intensification.

Wildflower areas are a popular agri-environment scheme to counteract agro-biodiversity loss. Yet, their benefits are controversially discussed. Since inconsistent benefits may be owed to landscape context and temporal dynamics, we applied a multi-year study to unravel effects of permanent and transient habitats on ground-dwelling arthropods in wildflower areas and cereal fields.Across three consecutive years, we studied activity density, species richness and community composition of rove beetles, carabid beetles and spiders in ten pairs of wildflower areas and cereal fields along independent gradients of proportions of permanent semi-natural habitats or transient wildflower areas.Arthropod responses to the proportions of permanent semi-natural habitats often followed a hump-shaped pattern, whereas transient wildflower areas seemed to drive linear responses. An interactive effect on rove beetle richness in wildflower areas implies that benefits were highest either at intermediate proportions of permanent semi-natural habitats or at lower proportions, but with additional availability of transient wildflower areas or in landscapes with low proportions of permanent semi-natural habitats, but high proportions of wildflower areas. However, ground-dwelling arthropod activity density or species richness did not systematically increase over the three study years.Our results suggest that both permanent and transient habitats differ in how they affect biodiversity, possibly due to different temporal continuity and resource diversity. Benefits of permanent semi-natural habitats seemed highest at an equilibrium between an increasing resource-related species pool and an increasing diversity dilution, whereas benefits of transient wildflower areas seemed to increase with resource complementarity and connectivity at the landscape scale. Nevertheless, both habitats seem to complement each other and considered in concert, seem to be most effective in promoting benefits of wildflower areas to ground-dwelling arthropods at intermediate landscape complexity. The substantial variation in diversity patterns among years with weather extremes, suggests that optimizing benefits of wildflower areas requires further multi-year studies.

Extensively managed grasslands are globally recognized for their high biodiversity value. Over the past century, a continuous loss and degradation of grassland habitats has been observed across Europe that is mainly attributable to agricultural intensification and land abandonment. Particularly insects have suffered from the loss of grassland habitats due to land-use change and the decrease in habitat quality, either due to an increase in livestock density, higher mowing frequency, and an increase in nitrogen fertilization, or by abandonment. However, only a few studies have used nationwide datasets to analyse the effects of land cover and land-use intensity on insects. It further remains largely unexplored how these effects are modulated by species traits, i.e. habitat specialisation and mobility. Using nationwide butterfly data originating from the German Butterfly Monitoring Scheme, we investigated the effect of three indicators related to land cover and agricultural land-use intensity on species richness as well as trait composition of butterfly communities. Based on agricultural census data at the municipality scale, we calculated the share of permanent grasslands (measure of habitat availability), the total livestock density (proxy for organic fertilization) and the livestock density of domestic herbivores (proxy for management intensity in grasslands) within a 2 km buffer surrounding each butterfly transect. To analyse the relationships between butterflies and indicators of land cover and land-use intensity, we applied generalised linear mixed effect models. We found a negative relationship between butterfly species richness and the livestock density of domestic herbivores. Further, the ratio of butterfly generalist to specialist species shifted towards generalists and the size of butterflies increased with higher herbivore livestock density, indicating a shift in communities towards mobile habitat generalists. Our results are in accordance with previous studies carried out across smaller geographic extents, highlighting the importance of low herbivore livestock densities to halt the loss of pollinating insects and safeguard biodiversity and associated ecosystem services in agricultural landscapes. We here demonstrate that indicators based on livestock distribution data at the municipality scale can provide insights into processes and spatial diversity patterns of butterflies at the national level. Further, we highlight potentials and limitations of using agricultural census data to quantify and assess effects of land cover and land-use intensity on butterflies, and make recommendations for further research needs.

Conservation of biodiversity alongside agriculture is now a global priority. Tree-nesting waterbirds have a tenuous relationship with farmlands because their survival requires farmers to retain trees and wetlands amid croplands. Research on such birds is rare on tropical and sub-tropical agricultural landscapes where high human densities and intensive farming ostensibly deteriorate breeding conditions. We explored breeding ecology and nest site selection by the single-nesting Woolly-necked Stork (Ciconia episcopus) in Haryana, north India using 298 nests from 166 locations discovered between 2016 and 2020. We determined the relative strengths of association of nest locations with natural features (trees, wetlands), human presence (habitation) and artificial water sources (irrigation canals) to understand cues used by breeding storks to situate nests. Woolly-necked Stork brood size from 42 successful nests was relatively high (3.1 ± 0.9 SD), with nests close to human habitation and wetlands having smaller broods. Storks showed high nest site fidelity (44.5% of sites used > 1 year), rarely nested on man-made structures (electricity pylons; 8.4%), and distributed nests in a clumped pattern. Woolly-necked Storks situated nests ambivalent to natural features but associated strongly with man-made features (positively with irrigation canals; negatively with human habitation). Contrary to expectations, most nests were not on the tallest trees but on the medium sized, native Dalbergia sissoo though storks situated nests on two tall trees (native Ficus religiosa and exotic Eucalyptus sp.) far more than the trees’ availability. All three tree species were favoured either for traditional agroforestry or local religious beliefs. Traditional agriculture in Haryana supported a substantial breeding population of Woolly-necked Storks facilitated by agriculture-related components rather than existing natural features. This novel scenario contradicts conventional narratives that suggest multi-season small holder tropical and sub-tropical agriculture degrades breeding conditions for waterbirds. Our findings in Haryana reiterate the need to assemble a diverse conservation toolkit of different locally relevant mechanisms supporting biodiversity amid cultivation.

Super high-density olive groves (>800 trees ha -1 ) are rapidly expanding in olive oil producer countries, which entails a strong modification of the olive growing system with important agronomic, economic, sociocultural, and environmental consequences. Among them, the latter is particularly unknown. The aim of this paper is to bring the attention on the environmental impacts of super high-density olive groves, by systematically reviewing the current evidence and identifying knowledge gaps yet to be filled. As a result, we can argue that new super high-density olive plantations reduce habitat heterogeneity and complexity, and the younger trees of these plantations impoverish habitat quality for farmland biodiversity. In addition, the high input use (e.g. phytosanitary treatments, fertilisers and water supply) may entail ecological impacts as well. Therefore, we conclude that i) new highly intensive olive groves should be limited to areas with lower ecological value; ii) consumers should have more information concerning how is produced the olive oil they buy, including the environmental impacts produced; iii) agricultural policies should be reformulated following the provider-gets principle; iv) input use (fertilisers, pesticides, water, etc.) should be gradually optimised to reduce the environmental impact; and finally, v) more research is necessary to foster decisions based on science., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)