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Landscape heterogeneity is considered a promising option for building resilient and sustainable agroecosystems. Understanding the relationships between farmland soil organic carbon (SOC) and landscape heterogeneity can support soil carbon sequestration and better serve food security and climate change. However, the influence extent and optimal scale of farmland landscape heterogeneity (i.e. landscape composition and landscape configuration heterogeneity) on SOC remains unclear. In this study, we established the relationships between multi-scale landscape heterogeneity and SOC in a typical grain-production county of northeast China. Stepwise regression results showed that when the buffer radius was 2000 m, the interpretation of SOC by landscape heterogeneity was the largest. The effects of landscape composition and landscape configuration on SOC were further decomposed by Variance Partitioning Analysis, and we found that independent interpretation ability of landscape configuration (8%) exceeded landscape composition (7%). The result of soil mapping combined with landscape indexes also showed that landscape configuration contributed more to the increased accuracy. Moreover, we found that correlation between configuration indexes and SOC at the class level was less related than that at the landscape level, among which the two most important indexes were Mean Fractal Dimension Index (FRAC_MN) and Number of Patches (NP). FRAC_MN was even more important than natural factors, indicating the validity of landscape as an indicator of human activities should not be ignored when considering farmland SOC. Overall, the results of this study revealed that the negative effects of agricultural intensification on SOC can be buffered to a certain extent by increasing the complexity of patch shape and reducing the degree of landscape fragmentation at the landscape level, providing hope for the sustainable development in intensive agricultural areas. In addition, due to the scale effect of landscape heterogeneity on farmland SOC, we suggest that decision makers should consider the spatial scale in landscape allocation and planning. This study provides a scientific reference for realizing the balance between grain production and ecological function in intensive agricultural areas., Competing Interests: Declaration of competing interest No conflict of interest exists in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Agricultural systems have been continuously intensified to meet rising demand for agricultural products. However, there are increasing concerns that larger, more connected crop fields and loss of seminatural areas exacerbate pest pressure, but findings to date have been inconclusive. Even less is known about whether increased pest pressure results in measurable effects for farmers, such as increased insecticide use and decreased crop yield. Using extensive spatiotemporal data sampled every 2 to 3 d throughout five growing seasons in 373 cotton fields, we show that pests immigrated earlier and were more likely to occur in larger cotton fields embedded in landscapes with little seminatural area (<10%). Earlier pest immigration resulted in earlier spraying that was further linked to more sprays per season. Importantly, crop yield was the lowest in these intensified landscapes. Our results demonstrate that both environmental conservation and production objectives can be achieved in conventional agriculture by decreasing field sizes and maintaining seminatural vegetation in the surrounding landscapes., Competing Interests: The authors declare no competing interest.

European nature conservation has a strong focus on farmland harbouring threatened species that mainly co-occur with traditional agriculture shaped way before the green revolution. Increased land-use intensity in agriculture has caused an alarming decline in farmland biodiversity during the last century. How can a landscape perspective contribute to fostering our understanding on causes and consequences of farmland biodiversity decline and improving the effectiveness of conservation measures? To answer these questions, we discuss the importance of landscape compositional and configurational heterogeneity, understanding ecological mechanisms determining how landscape structure affects farmland biodiversity and considering the interplay of farmland biodiversity and ecosystem service conservation., (© 2020. The Author(s).)

Intensively managed flowering crops like canola (Brassicales: Brassicaceae) (oilseed rape, OSR) provide significant short-term nectar resources for pollen consumers. They may also play important roles as annual "service strips" in temporarily promoting predatory invertebrates. We set out to test this assumption by comparing overall and functional group-specific species richness, activity density, and assemblage composition of carabids (Coleoptera: Carabidae) and spiders (Araneae), in three types of service strips-OSR, woody, and grassy strips established in direct vicinity to cropland. OSR strips were found to harbor the highest carabid species richness and activity density of small carabids. The activity density of carabids overall and of omnivorous species, the species richness and activity density of spiders across size classes and feeding strategies were all significantly reduced in woody strips. The percentage of seminatural habitat in the wider landscape was positively linked to the activity density of spiders overall, ground hunting and large spiders, whereas in carabids, positive effects were limited to large species occurring in grassy strips. Habitat type was the main predictor of both carabid and spider assemblage composition. Our results indicate that carabid and spider activity density across functional groups responded more strongly to changes in the landscape composition than the diversity of individual taxonomic groups. For agricultural landscape management, the establishment of habitat mosaics that include regular OSR could promote abundant, species-rich predatory invertebrates particularly in early spring. In contrast, structurally homogenous woody strips represent limited value in promoting the investigated biological pest control agents., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America.)

Background: Landscape crop composition surrounding agricultural fields is known to affect the density of crop pests, but quantifying these effects, as well as measuring how they translate to changes in yield, is difficult. Using a large dataset consisting of 1498 records of commercial cotton production in California between 1997 and 2008, we explored the relationship between landscape composition and cotton yield, the density of Lygus hesperus (a key cotton pest) at field-level and within-field spatial scales and pesticide use., Results: We found that the crop composition immediately adjacent to a cotton field was associated with substantial differences in cotton yield, L. hesperus density and pesticide use. Furthermore, crops that tended to be associated with increased L. hesperus density also tended to be associated with increased pesticide use and decreased cotton yield., Conclusion: Our results suggest a possible mechanism by which landscape composition can affect cotton yield: by increasing the density of pests which in turn damage cotton plants. Our quantification of how surrounding crops affect pest densities, and in turn yield, in cotton fields has significant impacts for cotton farmers, who can use this information to help optimize crop selection and ranch layout. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

The expansion of pollinator-dependent crops, especially in the developing world, together with reports of worldwide pollinator declines, raises concern of possible yield gaps. Farmers directly reliant on pollination services for food supply often live in regions where our knowledge of pollination services is poor. In a manipulative experiment replicated at 23 sites across an Ethiopian agricultural landscape, we found poor pollination services and severe pollen limitation in a common oil crop. With supplementary pollination, the yield increased on average by 91%. Despite the heterogeneous agricultural matrix, we found a low bee abundance, which may explain poor pollination services. The variation in pollen limitation was unrelated to surrounding forest cover, local bee richness and bee abundance. While practices that commonly increase pollinators (restricted pesticide use, flower strips) are an integral part of the landscape, these elements are apparently insufficient. Management to increase pollination services is therefore in need of urgent investigation., (© 2016 The Authors.)

Understanding the impact of herbivores on croplands is critical to developing sustainable agricultural landscapes. Here, we test the hypothesis that field size and landscape structure modulate the levels of herbivory in cowpea and maize subsistence croplands in Brazilian drylands. We conducted the study in nine small-scale farms with varying levels of landscape structure and field sizes (0.10–1.67 ha). In each farm, we haphazardly sampled 20 plants of maize and cowpea. The frequency of foliar herbivory was high for both crops (0.45–0.72), but the average magnitude of damage was low (<3% of leaf surface in both crops), indicating that herbivory is not an ecosystem disservice. Nonetheless, the field size and level of human impact on the landscape matrix were positively related to the frequency and magnitude of damage on maize foliage and cowpea foliage and pods. Landscape composition (proportion of woodland/forest surrounding the field) and configuration (number of surrounding woodland/forest patches) had weaker effects on herbivory levels, mixing positive and negative effects on both crops. Our findings indicate that herbivory attack is not concerning in the agricultural fields studied, but suggest that maize and cowpea should be preferably grown in small fields surrounded by an environmental-friendly matrix and patches of conserved ecosystems. [ABSTRACT FROM AUTHOR]

Pest‐regulating natural enemies often require crop and non‐crop habitats to persist and be effective. These habitats offer hibernation sites, alternative prey or floral resources but can also be complementary in when they provide resources. The relative contribution of these different habitats to the performance of pest‐regulating insects is largely unknown, since it is difficult to study empirically. Landscape‐based population‐dynamical modelling can fill this research gap.In this study, we modelled the dynamics of predatory hoverflies (Diptera: Syrphinae) and their aphid prey in a collection of habitats. These hoverflies are dependent on different habitats for different reasons. While their larvae predate on aphids, adult hoverflies require floral resources. Resources are often segregated in different habitats. In addition, they are only temporarily available in any habitat type. In our model, hoverflies move between different habitats and select where to feed and where to produce off‐spring based on optimal foraging considerations. The model represents habitats common in arable landscapes and their temporal availability of resources is parameterized based on field observations.The model shows that effective pest suppression will only occur in the presence of at least three different habitats, including two crops that provide prey resources at different times of the year. A woody habitat with shrubs and trees provide aphid prey very early and late in the season, whereas an early crop and a late crop cover the period in between. In addition, these habitats need to provide floral resources in the same period as aphids, for example by flower strips in the margins of crop fields or blossoming trees or shrubs in the woody habitat. Under the model assumptions, the best pest suppression is obtained when the woody habitats take up 6% to 10% of the landscape. In addition to yearly population fluctuations, also bi‐ or multi‐yearly cycles may occur, depending on the composition of the landscape.Synthesis and applications. Our model shows when an agricultural landscape is 'complete' for natural enemies (and for effective pest control). For this, it needs to contain multiple habitats that supply floral and prey resources in different periods of the year. [ABSTRACT FROM AUTHOR]

Bumble bees are integral pollinators of native and cultivated plant communities, but species are undergoing significant changes in range and abundance on a global scale. Climate change and land cover alteration are key drivers in pollinator declines; however, limited research has evaluated the cumulative effects of these factors on bumble bee assemblages. This study tests bumble bee assemblage (calculated as richness and abundance) responses to climate and land use by modeling species‐specific habitat requirements, and assemblage‐level responses across geographic regions. We integrated species richness, abundance, and distribution data for 18 bumble bee species with site‐specific bioclimatic, landscape composition, and landscape configuration data to evaluate the effects of multiple environmental stressors on bumble bee assemblages throughout 433 agricultural fields in Florida, Indiana, Kansas, Kentucky, Maryland, South Carolina, Utah, Virginia, and West Virginia from 2018 to 2020. Distinct east versus west groupings emerged when evaluating species‐specific habitat associations, prompting a detailed evaluation of bumble bee assemblages by geographic region. Maximum temperature of warmest month and precipitation of driest month had a positive impact on bumble bee assemblages in the Corn Belt/Appalachian/northeast, southeast, and northern plains regions, but a negative impact on the mountain region. Further, forest land cover surrounding agricultural fields was highlighted as supporting more rich and abundant bumble bee assemblages. Overall, climate and land use combine to drive bumble bee assemblages, but how those processes operate is idiosyncratic and spatially contingent across regions. From these findings, we suggested regionally specific management practices to best support rich and abundant bumble bee assemblages in agroecosystems. Results from this study contribute to a better understanding of climate and landscape factors affecting bumble bees and their habitats throughout the United States. [ABSTRACT FROM AUTHOR]

Conversion of land for agricultural use is a leading driver of global biodiversity loss. Natural and semi‐natural lands within agricultural landscapes are targeted for protection because they provide habitat for many organisms.Pothole (or kettle) wetlands occur across the Northern Hemisphere and are a focus for conservation both because of their location within agriculturally intensive landscapes and their importance to vertebrates, especially migratory birds.Recent evidence suggests that wetlands may also be an important habitat for arthropods, including insects that provide ecosystem services. To understand how insects associate with wetlands and landscape features, we examine the relationship between bumblebees (Bombus), and wetland area, cropland area and wetland perimeter‐area ratio.We found that wetland area is significantly positively associated with the occurrence and abundance of the species studied. We also found that the relationship between bumblebees and wetland perimeter‐area ratio varied across the growing season. This suggests that the importance of wetland edge as a foraging habitat varies across the season.These results show the utility of wetlands to bees, though their resources are likely not being used uniformly by all bumblebee species or across the entire growing season. Our results also suggest that pothole wetlands in agricultural landscapes are likely to support biodiversity, and their conservation contributes to overall ecosystem health and function. [ABSTRACT FROM AUTHOR]

The loss and fragmentation of natural habitats due to agricultural intensification have a strong negative impact on farmland biodiversity. The concomitant isolation of essential resources may exert selection pressures toward increased dispersal performance in flying insects, possibly resulting in differences in flight morphology and dispersal propensity across landscapes. Here, we compared condition, flight morphology, dispersal capacity, and propensity of the common butterfly Pieris rapae among four pairs of highly fragmented "modern" and less fragmented "traditional" agricultural landscapes. We did not find differences between landscape types, but between locations and sexes. These results are not entirely unexpected, as P. rapae is a highly mobile generalist species, able to exploit temporarily available resources such as rapeseed in modern agricultural landscapes. In addition, our negative results may suggest a lack of time for evolutionary change such that differences may appear in the future. However, more specialized species with low dispersal ability may show clearer patterns and may well suffer from habitat fragmentation, and investigating such interrelation is an important task for future research. [ABSTRACT FROM AUTHOR]

Biological control is a key ecosystem service in arable lands, but its effectiveness varies according to environmental and biotic contexts. Cascading interactions between several trophic levels can affect natural enemies and their efficacy.Here, we analysed how multitrophic interactions drive weed seed control under contrasting farming systems and landscapes. In particular, we analyse how the presence of higher‐order predators and alternative prey affects the weed seed consumption by seed predators. We monitored 30 cereal fields organised into 15 pairs, each comprising one conventional and one conservation agriculture field, sampled along a gradient of proportion of conservation agriculture in the landscape.We found that local and landscape management under conservation agriculture favours the presence of seed predators like carabids and rodents, higher‐order predators like shrews and alternative animal prey. Weed seed predation is promoted by conservation agriculture through an increase in the number of seed predators. However, alternative animal prey reduces the efficacy of carabids to consume seeds, probably due to a prey‐switching behaviour. Similarly, shrews negatively affect the activity‐density of carabids, resulting in an indirect negative effect on seed predation.Synthesis and applications: Our study highlights that the implementation of conservation agriculture can improve the provision of biological control but the resulting effect may be partially limited by the increased complexity of trophic interactions. The different trophic levels respond to local management and/or the surrounding landscape with cascading effects on the delivery of weed control. Our study highlights the importance of considering not only the direct effects of seed predators, but also the indirect effects of higher‐order predators and alternative prey when predicting the level of weed biological control. [ABSTRACT FROM AUTHOR]

Intensively managed agricultural landscapes often lack suitable habitats to support diverse wildlife, particularly harming pollinator communities. Besides mass flowering crops, remnant patches of natural and semi‐natural vegetation may play a key role in maintaining and conserving biodiversity. Yet, the effects of different natural habitats, including forests and grasslands, on different pollinator communities are poorly understood at the landscape scale.We examined the abundance, richness, and diversity of wild bees and hoverflies, two key pollinator groups, across a land‐use gradient spanning forest edges, grassland, wildflower strips, and sunflower monoculture. We also examined the distribution of hoverfly larvae trophic guilds and wild bee nesting traits across the above‐mentioned land‐use gradient. Finally, we evaluated the impact of landscape structure (forest, grassland, and water cover in the surrounding landscape) on pollinator community composition.Our results indicate that forest and grassland habitats supported a higher abundance and greater richness of pollinators than wildflower strips and sunflower monocultures. Furthermore, hoverflies were more sensitive to habitat and floristic homogenization than wild bees. Sunflower and wildflower habitats also hosted a lower diversity of larvae trophic guilds and wild bee nesting guilds as compared to forests and grasslands.Our study suggests that conserving and restoring forest and grassland habitats within agricultural mosaics may serve as the main 'refuge' for wild pollinators. [ABSTRACT FROM AUTHOR]

Agricultural intensification and expansion has been suggested to be a major driver of the loss of biodiversity and associated ecosystem services. Recent studies have shown that landscape‐level effects in addition to on‐site management are of significant importance for insect declines.We here compared carabid beetle (Coleoptera, Carabidae) assemblages of wet meadows among three pairs of highly fragmented 'modern' and less fragmented 'traditional' agricultural landscapes, using pitfall trapping.Taxonomic diversity and abundance of Carabidae did not differ between modern and traditional landscapes, whereas the proportions of brachypterous, large‐bodied, and habitat specialist species were lower in modern compared to traditional landscapes.These results suggest that landscape type affects functional rather than taxonomic carabid beetle diversity, based on species turnover.To preserve functional diversity in agricultural landscapes, conservation strategies should consider the landscape level in addition to on‐site management, by securing connectivity between remnants of semi‐natural habitats. [ABSTRACT FROM AUTHOR]

More sustainable and environmentally friendly agricultural practices, including ecological intensification, are needed to reduce biodiversity loss and environmental degradation.We evaluated the potential of ecological intensification through the enhancement of pollination services in an intensively managed and insect‐pollinated crop, Macadamia integrifolia. We compared the effects and importance of agronomic practices that include agronomic input (i.e. irrigation and managed honeybees), orchard design requiring no external inputs (i.e. spatial orchard structure) and landscape factors in 10 South African macadamia orchards.In comparison to experimental pollinator exclusion, insect pollination increased the initial and final nut set by 304% and 23%, respectively. However, nut set was pollination limited as hand pollination further improved nut set.Flower visitation rates increased with the cover of semi‐natural habitats in the surrounding landscape (1 km radius). This effect was outperforming the effect of the number of managed honeybee colonies, as agronomic practice.Initial nut set increased with orchard design and flower visitation rates. Perpendicular orientation of the planted macadamia rows towards the semi‐natural habitats increased initial nut set more than threefold compared to parallel row orientation. The initial nut set was 80% higher at the edge to semi‐natural habitats than in the orchard centre. In contrast, agronomic practices, such as irrigation, did not increase initial nut set. Final nut set depended on the preconditions of the initial nut set, additionally, high altitudes and the position in the centre of the orchard had positive effects.Synthesis and applications: Pollination services were prerequisites for high yields in macadamia and could be improved without further agronomic input. Especially, the orchard design, that is, spatial arrangement of tree rows and semi‐natural habitats at local and landscape scales, was more important to boost insect pollination and the initial development of macadamia nuts than agronomic practices, such as high levels of irrigation. Considering the urgency to reduce the environmental impacts of agricultural production, we highlight the high potential of ecological intensification by a smart orchard design and the restoration and conservation of semi‐natural habitats in the orchards and their surrounding landscape. [ABSTRACT FROM AUTHOR]

Migratory bird populations can be limited by events in disparate parts of the world. Birds wintering in tropical regions are facing rapid habitat loss, climate change, and intensive agricultural regimes, potentially contributing to population declines. However, an understanding of basic nonbreeding ecology of species, such as habitat and space use, is critical for determining if this is the case. Populations of the nocturnal/crepuscular Eastern Whip-poor-will (Antrostomus vociferus) have declined by 70% since the 1960’s, yet data on the species are sparse outside of the breeding season. We extracted data from 41 archival GPS tags deployed on whip-poor-wills and estimated nonbreeding home ranges and land covers used. We used satellite imagery and stable carbon and nitrogen isotope values from claws grown during the nonbreeding season to analyze how land cover and habitat moisture impacted home range size and relative trophic level. Forest was by far the most prevalent land cover used by whip-poor-wills, occurring in all home ranges and accounting for >80% of diurnal roosting points. We found that less forest, the presence of agriculture, and more edge (irrespective of land cover) were associated with larger home ranges. Stable isotope values differed by broadscale ecoregion but not local land cover characteristics in our study, indicating that regional idiosyncrasies or broadscale processes can be more important in determining stable isotope ratios. Our findings suggest that the loss, fragmentation, and replacement of forest by agriculture in the core of the whip-poor-will’s nonbreeding range may represent a threat to the species, as they rely heavily upon forest, and appear to alter space use in response to changes in forest cover. [ABSTRACT FROM AUTHOR]

The majority of the world's plants rely on animal pollinators for reproduction, making pollination a key ecosystem service for the maintenance of natural and cultivated plant communities. Mutual interactions between plants and pollinators, also called "plant-pollinator networks", are becoming increasingly vulnerable due to the intensification of anthropogenic land use and climate change. Thus, due to the rapid decline of semi-natural grasslands in the Northern Apennines (Italy), we aimed at understanding how the fragmentation of these habitats, the spatial distribution, and the amount of semi- and natural areas surrounding them, could affect species diversity and plant-pollinator networks. Specifically, in the Northern Apennines, we monitored semi-natural grasslands belonging to the EU habitat type 6510 to evaluate the effect of fragmentation on plant and pollinator richness and on the plant-pollinator network. We carried out generalized linear models considering three taxonomical and six network descriptors as response variables and the combinations of grasslands size and isolation, as well as 10 other factors describing landscape composition as explanatory variables. We found a well-structured plant-pollinator network, characterized by a high diversity of both plants and pollinators, with mutual relations marginally specialized, highly affected by habitat fragmentation and the land use of surrounding grasslands. Moreover, large and neighboring patches increased pollinator richness and improved the overall network structure while the occurrence of meadows and shrubs around fragmented patches was important to ensure the continuity of floristic resources. Finally, extensive croplands and agricultural settlements significantly reduced plant and pollinator diversity, favoring generalist (probably invasive) species, which however increased the strength and stability of the network. [ABSTRACT FROM AUTHOR]

Context: Manipulating crop diversity in the landscape has been suggested as a promising management option to enhance biocontrol but how crop diversity independently of other important aspects of landscape structure affects predator and pest abundances remain largely unexplored. Objectives: Our study assessed the relative and interactive effects of crop composition and configuration on aphids and their generalist predators, i.e. ladybirds, spiders and lacewings. Methods: We sampled arthropods in 47 cotton fields and 21 wheat fields in Hebei, China, located along three landscape gradients: crop diversity (Shannon diversity of crops ranging from 0.27 to 1.32 corresponding to a crop richness varying from 2 to 7 different crops), crop configurational (crop edge density varying from 0.0012 m/ha to 0.066 m/ha) and proportion of semi-natural habitats (varying from 0.5% to 56%). Results: Crop diversity never had any effect on arthropod communities and we found no effect of the proportion of semi-natural habitats on natural enemies' abundances. Aphid abundance was positively correlated with the proportion of semi-natural habitats both in cotton and wheat fields. Lacewing abundance benefited from configurational heterogeneity as abundances increased with crop edge density. Conclusions: Our result provide evidence that crop diversity is probably not the best management option to enhance biocontrol of aphids in Chinese landscapes and confirms that the amount of semi-natural habitats in the landscape is a critical aspect shaping arthropod communities. It also indicates that manipulating crop edge density by promoting agricultural landscapes with small field size for instance can benefit natural enemies of crop pests. [ABSTRACT FROM AUTHOR]

The majority of the world’s plants rely on animal pollinators for reproduction, making pollination a key ecosystem service for the maintenance of natural and cultivated plant communities. Mutual interactions between plants and pollinators, also called “plant-pollinator networks”, are becoming increasingly vulnerable due to the intensification of anthropogenic land use and climate change. Thus, due to the rapid decline of semi-natural grasslands in the Northern Apennines (Italy), we aimed at understanding how the fragmentation of these habitats, the spatial distribution, and the amount of semi- and natural areas surrounding them, could affect species diversity and plant-pollinator networks. Specifically, in the Northern Apennines, we monitored semi-natural grasslands belonging to the EU habitat type 6510 to evaluate the effect of fragmentation on plant and pollinator richness and on the plant-pollinator network. We carried out generalized linear models considering three taxonomical and six network descriptors as response variables and the combinations of grasslands size and isolation, as well as 10 other factors describing landscape composition as explanatory variables. We found a well-structured plant-pollinator network, characterized by a high diversity of both plants and pollinators, with mutual relations marginally specialized, highly affected by habitat fragmentation and the land use of surrounding grasslands. Moreover, large and neighboring patches increased pollinator richness and improved the overall network structure while the occurrence of meadows and shrubs around fragmented patches was important to ensure the continuity of floristic resources. Finally, extensive croplands and agricultural settlements significantly reduced plant and pollinator diversity, favoring generalist (probably invasive) species, which however increased the strength and stability of the network.

Different variables operate simultaneously at different spatial scales, influencing community composition and species distribution. This knowledge could improve management and conservation practices in managed menaced forests. The objective of this work was to determine the influence of landscape and stand variables on the bird assemblage of the managed Nothofagus antarctica forest of Tierra del Fuego (Argentina). We used data from bird point counts (three or four censuses during middle summer of two consecutive years) located at 48 sites distributed at four ranches. At each site, we extracted landscape variables with Fragstat software from the forest patches, the cover classes, and the whole landscape. We also evaluated local stand characteristics, such as forest structure, ground cover, and food availability, including understory plant cover usually consumed by birds and available arthropods. Data were evaluated by detrended and canonical correspondence analyses. We found that landscape configuration (e.g., forest patch shape) and local stand variables (e.g., canopy cover) influenced bird assemblage more than landscape composition. Moreover, bird functional groups responded differently to different spatial scale variables (e.g., forest specialist species were associated with forest structure, but species that use low strata to nest and feed were associated with landscape configuration variables), demonstrating the importance of using multiple spatial scales to better understand bird species requirements. The combination of practices that promote some local characteristics (e.g., high canopy cover) and more complex landscape configurations could simultaneously favor different bird species groups and improve the effectiveness of management and conservation strategies.

Reconciling biodiversity conservation with increasing demand for agricultural production is a major challenge. A long-running discourse that addresses this challenge is the land-sparing vs land-sharing debate. However, the land-sparing vs land-sharing framework has also been criticized for favouring a dichotomous worldview, which contradicts the real-world complexity of agricultural landscapes. Here, we review land-sparing and land-sharing measures with a focus on European landscapes. Land-sparing is needed to preserve the last of Europe's wilderness (2.2% of the land) but will fail to conserve traditional agroecosystems and a wealth of synanthropic species with a long-history of human land-use influence. This is why land sparing should be combined with wildlife-friendly land-sharing practices needed for the preservation of these low-intensity agroecosystems, including European High Nature Value Farmland (15-25% of the land), which is of outstanding conservation value. By promoting generalist species associated with wildlife-friendly farming, land-sharing also enhances ecosystem services provision to agriculture, including pollination and biological pest control. Current land-sharing practices cover multiple spatial scales from local (e.g. wildflower strips) to field (e.g. organic farming) to landscape scale (e.g. diversified farming systems). In addition, productivity outcomes of land-sharing vary greatly, from comparatively high productivity (e.g. pastures for organic production) to agroecosystems that no longer provide any economic returns and are managed mostly for conservation purposes (e.g. dry grasslands). From an economic point of view, the latter may even be defined as land-sparing, highlighting that land-sparing and land-sharing sensu stricto are merely the endpoints of a spare-share continuum of the many agricultural practices in European landscapes. The best biodiversity outcomes and potentially smallest ecological-economic trade-offs result from landscape management that combines measures like agri-environment schemes and organic farming with small field sizes and high crop diversity to enhance spatial and temporal resource complementarity for associated species. Despite increasing progress towards win-win solutions, biodiversity-productivity trade-offs remain widespread, nonetheless. Multifunctional landscapes should therefore include elements from both land-sparing (e.g. natural ecosystems, intensively managed arable fields) and land-sharing (e.g. organic agriculture, agri-environment schemes) to halt declines of farmland biodiversity under increasing agricultural demand. Landscape heterogeneity is key to facilitate landscape connectivity, to avoid species extinctions in spared natural habitats and to promote spillover of organisms and ecosystem services from shared landscape elements to agricultural land. To halt ongoing losses of farmland biodiversity and to promote sustainable multifunctional landscapes, the post-2020 Common Agricultural Policy of the European Union should better reflect the need for agricultural diversification, sustainable agricultural practices and greater landscape heterogeneity. [ABSTRACT FROM AUTHOR]

We present evidence of plasticity in habitat use and range extension of the striped hog-nosed skunk (Conepatus semistriatus) in Brazil. We first compiled literature records of C. semistriatus across its known distribution (N = 390), added new records from primary data (N = 10), and compared the main landscape composition (forest, savannah, grassland, agriculture) among these occurrence sites (N = 400). We unveil that landscape composition among occurrence sites varied widely within and among biomes in Brazil (Caatinga, Cerrado and Atlantic Forest), indicating C. semistriatus presence from dense forested habitats to grasslands and anthropogenic areas (especially agricultural landscapes). Almost 30% of the occurrence records of C. semistriatus are outside of the species known distribution, including records in ecotones between Cerrado-Amazonia biomes, extending its occurrence area in 449,118 km2. We conclude that habitat modification is a driver for the occurrence of C. semistriatus in dense forested habitats, facilitating its distribution expansion to previously unexpected areas. [ABSTRACT FROM AUTHOR]

Abstract The intensification of agricultural practices that Western nations have experienced after World War II has led to an alarming decline in farmland biodiversity. With the aim of stopping and even reversing this decline, agri-environment schemes (AES) have been implemented in many European countries since the 1990s. In Switzerland, farmers are required to manage at least 7% of their land in the form of biodiversity promotion areas (BPA), which are extensively managed, wildlife-friendly farmland habitats such as hay meadows and traditional orchards. We investigated how the occurrence and characteristics of these BPA influence birds and butterflies in the Swiss lowlands. Butterfly species richness and abundance increased by 22% and 60%, respectively, when the proportion of BPA in the landscape increased from 5% to 15%. Likewise, bird species richness increased, but to a lesser extent, with the proportion of BPA in the landscape. For birds, the proportion of BPA characterized by a high ecological quality played a role in promoting both priority-farmland and red-listed species. For both taxonomic groups, the amount and quality of BPA habitats contributed more to species richness than their spatial configuration, connectivity included. This study shows that AES measures implemented at the field scale have positive effects on mobile species that are noticeable at the landscape scale, and that the fraction of AES in the cultivated landscape matters more than their spatial configuration, which has strong implications for designing multi-functional agro-ecosystems. [ABSTRACT FROM AUTHOR]

Targeted conservation and promotion of wild bees in agroecosystems requires understanding of relationships between different groups of bees and available floral resources across land-use types during the season and at the landscape scale. Here, we quantified floral resource amount and diversity across habitat types at different times during the season at the scale of entire landscapes (500 m radius) across 20 different agricultural landscapes. Moreover, we examined whether floral resource metrics obtained from these high-resolution floral resource maps are more suitable to assess and predict abundance and species richness of different bee pollinator groups, including rare species and important crop pollinators, sampled in these agricultural landscapes compared to traditional land-cover metrics. Floral resource availability shifted from flower-rich woody vegetation early in the season to herbaceous vegetation such as grasslands and crops later in the season, which was associated with a ten-fold decline in overall floral resource availability. Forest edges had highest per-area floral contributions in spring, whereas floral diversity of grasslands, in particular if extensively managed, was continuously high. Total wild bee species richness, as well as rare species richness and abundance of important crop pollinators, increased with floral resource availability and/or diversity contributed by forest edges and floral diversity of permanent grasslands. Rare bee richness was also positively related to floral resource amount provided by crops. Total bee richness and important crop pollinator abundance, but not rare bee richness, were positively related to overall floral resource amount, but not floral diversity, in the landscape. Floral resource maps based on floral resource supply by major habitat types early or late in the season predicted wild bee species richness (R 2 =0.61) better than traditional descriptors of landscape composition such as proportion of semi-natural habitat. The pronounced temporal shifts in floral resource availability for pollinators from woody towards herbaceous vegetation during the season highlights the importance of taking a landscape-scale perspective on pollinator conservation. Our findings indicate that both rare bees and important crop pollinators benefit from complementary floral resources of forest edges and grasslands in agroecosystems. This reveals a potential synergy between the conservation of endangered species and the landscape scale management to promote pollination services. Our study also highlights that floral resource maps are useful tools in supporting more targeted pollinator conservation and pollination service management at the landscape level. • Floral resource complementarity across habitats during the season supports bees. • Pronounced floral resource shifts from woody to herbaceous vegetation during season. • Floral resources of forest edges and grasslands key for rare bees and crop pollinators. • Floral resource maps better predict wild bees than landscape composition. • Functional resource maps are useful tools for targeted pollinator conservation. [ABSTRACT FROM AUTHOR]

Wild bumblebees are key pollinators of crops and wild plants that rely on the continuous availability of floral resources. A better understanding of the spatio-temporal availability and use of floral food resources may help to promote bumblebees and their pollination services in agricultural landscapes. We placed colonies of Bombus terrestris L. in 24 agricultural landscapes with various degrees of floral resource availability and assessed different parameters of colony growth and fitness. We estimated pollen availability during different periods of colony development based on detailed information of the bumblebee pollen diet and the spatial distribution of the visited plant species. Total pollen availability did not significantly explain colony growth or fitness. However, when using habitat maps, the weight gain of colonies, the number of queen cells, and colony survival decreased with increasing distance from the forest. The better explanation of bumblebee performance by forest proximity than by (plant-inferred) pollen availability indicates that other functions of forests than pollen provision were important. The conservation of forests next to agricultural land might help to sustain high populations of these important wild pollinators and enhance their crop pollination services. Combining different mapping approaches might help to further disentangle complex relationships between B. terrestris and their environment in agricultural landscapes.

Abstract: The landscape heterogeneity hypothesis posits that increasing variance of land cover types in agricultural landscapes will increase landscape level biodiversity. This hypothesis, however, does not detail which component of landscape structural heterogeneity, compositional (the type and amount) or configurational (the shape and arrangement) has the greatest influence on biodiversity and at what spatial scale(s). We investigated how dung beetle (Scarabaeidae) alpha‐diversity responded to landscape structural heterogeneity at a variety of spatial scales in an agricultural mosaic‐landscape in north‐eastern Swaziland. We also compared the effect of these components to the effect of variation in the amounts of major land‐cover types in the landscape and plot level vegetation structure. We used pitfall traps to sample the dung beetle community along a gradient of heterogeneity and used linear mixed effects models to compare the effect of each component on dung beetle richness and Shannon diversity at four separate spatial scales (i.e. 1‐,1.5‐, 2‐ & 3‐km). Land‐cover diversity and number of patches represented compositional and configurational landscape heterogeneity respectively. Landscape compositional heterogeneity was negatively correlated with dung beetle richness at the 1.5‐km and 2‐km spatial scales. The percentage savanna in the landscape was positively correlated with dung beetle richness at the 3‐km and 2‐km scales. Landscape level heterogeneity may enhance diversity of some taxonomic groups, but this was not the case for dung beetles in a southern African savanna. The best way to maintain their diversity is to create or maintain large continuous blocks of savanna while limiting intensive agriculture. [ABSTRACT FROM AUTHOR]

In the past centuries, farmland has undergone a fundamental transformation through changed farming practices, such as the use of agrochemicals and advanced machine processing. Particularly since the 1970s, agriculturally driven land-use change has caused destruction of natural and semi-natural habitats, and as a consequence, severe loss of biodiversity. Hence, identifying landscape patterns and habitats that enhance species richness, and detecting species and traits that are most vulnerable to intensive land-use are prerequisites for conservation. To evaluate the effects of agricultural land-use and landscape composition on wild bees, we investigated 340 cross-transects in 34 test areas in the main agricultural regions of Austria within the framework of the biodiversity monitoring program BINATS. Using multivariate models (GLM, DCA), wild bees and potential explanatory parameters (e.g. Shannon landscape diversity index, plant diversity, flower cover) were documented, and their interrelationships analyzed. We found strong negative effects of increased agricultural land cover on species richness, abundance and functional richness. Species richness was positively correlated with an increasing area of semi-natural elements (e.g. extensive grassland, hedgerows, fallows) and the number of different habitat types, while wild bee abundance was best explained by the presence of semi-natural habitats and flower cover. Colletidae were significantly associated with the area of semi-natural elements, and were especially sensitive to agricultural intensification. Many species from communities that are present in complex landscapes disappeared in intensively managed farmland, and the majority of species decreased in response to simplified landscapes. A few species, however, even benefited. Our results emphasize the importance of diverse semi-natural elements and high regional flower cover within farmland for maintaining and enhancing species richness and abundance, and for promoting a positive spillover effect of pollinators to the surrounding agricultural landscape. Especially members of the family Colletidae, with a high proportion of specialized species, will benefit from diverse semi-natural habitat types. Given the unique importance of wild bees as pollinators of wildflowers and crops, it is crucial to improve and expand agri-environmental schemes to combat ongoing biodiversity loss in farmland. • Agricultural land-use had negative effects on species richness and abundance. • Bees were promoted by semi-natural elements, diverse habitat types and flower cover. • The family Colletidae was most positively affected by semi-natural elements. • The majority of species decreased in response to intensively managed farmland. • Agri-environmental schemes must be improved to combat biodiversity loss in farmland. [ABSTRACT FROM AUTHOR]

Ecology studies often require large datasets. The benefits of citizen science for collecting such datasets include the extension of spatial and temporal scales, and cost reduction. In classical citizen science, citizens collect data and send them directly to scientists. This may not be possible for the many biological groups for which specimen identification is difficult and requires high-level expertise. Here we report the results of an expert-assisted citizen science program where teachers from 20 French agricultural high schools collected bees, which were identified to species level by a panel of expert bee taxonomists. Overall the dataset included 70 collections (year × sampling site combinations) that resulted in 4574 specimens belonging to 195 species. We analysed this dataset using data freely available at a national scale on agriculture intensity and landscape composition. We found that species richness increased with increasing proportion of herbaceous semi-natural elements; species dominance decreased with increasing crop diversity; the proportion of above ground nesting species and specimens increased as the intensity of agricultural practices decreased. Comparing the results obtained with identification to species level and those obtained with higher taxa or parataxonomic approaches, we found that the loss of taxonomic resolution resulted in the non-significance of some results on the effects of environmental variables on bee assemblage-level attributes. Our study suggests that identification to species level is of great importance to detect the effects of global change on bees and that an expert-assisted citizen science paradigm could provide relevant results to guide conservation measures at a national scale. [ABSTRACT FROM AUTHOR]

Introduction: Long-term drought in the southern Great Plains increases the vulnerability of coupled human-environment systems at a variety of scales. Developing better understandings of the dynamics at regional scales will become increasingly important as long-established land-use regimes break down in the face of climate change, resource depletion, and evolving governance. To demonstrate differential vulnerability during drought periods, this study hypothesized that observed increases in woody vegetation in grasslands would vary across land-tenure regimes. We argue that differences in State Trust Land governance, in part, lead to differential land management practices that contribute to landscape change. Methods: The study area encompasses adjacent counties, Cimarron County in Oklahoma and Union County in New Mexico, with similar climate variability and agricultural economies. We analyzed National Land Cover Database (NLCD) land-cover maps from 1992 and 2011 to assess changes in landscape composition and structure between 1992 and 2011. Results: During both years under consideration, each county in the study region, across various land-tenure regimes, was dominated by herbaceous vegetation. However, there were changes in both composition and structure across the whole study area, in particular losses of herbaceous vegetation and increases in woody vegetation. The greatest gains in woody vegetation occurred in State Trust Lands of Cimarron County. Overall, the data suggest a fragmentation of herbaceous vegetation and a coalescing of shrubland patches. Conclusions: Research about the influence of land tenure on land management decisions, specifically the role of State Trust Land leases in overgrazing, informs the broader context of drought management in the southern Great Plains. Recommendations include continued research to highlight the specific mechanisms of land-tenure governance that drive landscape change. [ABSTRACT FROM AUTHOR]

Organic farming is credited as having numerous positive influences on the environment, among others the support of greater landscape diversity. This potential benefit is of particularly great relevance in the case of countries in Central and Eastern Europe, in which the agricultural landscape was damaged by the process of homogenization as a result of the collectivization of agricultural production. This article presents research focusing on the relationship between organic farming and landscape composition in selected locations with varying natural conditions within the Czech Republic. The first part of the research evaluates the overall development of landscape structure during the period of transition from socialist mass-production to farm management based on private companies and family farms. Analysis making use of the landscape metrics proved an increase in the heterogeneity and diversity of landscape between the years 1985 and 2006. The second part of the analysis focused on the relationship between farm management and changes in landscape use. The results showed differing trends in the studied locations, which do not depend on farm management alone, but also on other factors, especially natural conditions in agricultural landscape. [ABSTRACT FROM PUBLISHER]

Agricultural landscapes worldwide are under increased pressure to provide food, feed, fiber, and fuel for a growing human population. These demands are leading to changes in agricultural landscapes and subsequent declines in biodiversity. We used citizen science data from the North American Butterfly Association and remotely-sensed land cover data from the US Department of Agriculture to study relationships between agricultural landscape composition and butterfly community structure in the Midwestern US. Landscape-level butterfly species richness (based on rarefaction estimates) was highest in agricultural landscapes with relatively low amounts of cropland, relatively high amounts of woodland, and intermediate amounts of grassland and wetland. Rarefied richness generally declined with the dominance of any of these land cover types. Unlike other land cover types, urban development had a consistent negative effect on rarefied richness. Butterfly community structure (based on relative abundance) was also significantly related to the amount of cropland, woodland, grassland, and wetland in the landscape. The rarest butterfly species were associated with woodland-, grassland-, and wetland-dominated landscapes, likely due to their association with plant species occurring in savannahs, prairies, and marshes, respectively. Assuming that variation across space reflects changes over time, our results support conclusions from previous studies that removal of natural and seminatural habitats alters butterfly community structure and decreases species diversity in agricultural landscapes. [ABSTRACT FROM AUTHOR]

While landscape trajectories are increasingly used for tracking change in processes such as agricultural intensification and urbanization, analyses that combine environmental and human disturbances remain scarce. The aim of this study was to investigate the relationship between Shannon evenness, a measure of landscape composition, and spatial contagion, a measure of landscape configuration, within sixteen Canadian regions covering a gradient of land-uses and human disturbances: natural, semi-natural, urban, and agricultural. The agricultural regions showed generally lower variation in contagion and evenness and overall lower contagion values (smaller patches), leading to steeper contagion-evenness slopes than in the other region categories. In addition, the sampled agricultural regions were much more similar to each other than were the sampled regions within each of the other three region categories. These results indicate that the process of agricultural development (at least in western Canada) leads to a reduction in pattern variation and an alteration of the expected relationships among pattern metrics in agricultural regions. This possibility is supported by a neutral model of patch dynamics, suggesting that the characteristic scale of disturbances is a generic structuring process of landscape trajectories. [ABSTRACT FROM AUTHOR]

Abstract: Increases in farming practice intensity and landscape simplification are two well-known threats for many farmland bird species. Nevertheless, the effects of these two factors may differ strongly among species. Here, we propose to use the specialist–generalist concept to assess which bird species are most affected by these two factors. Bird density and intensity of farming practices were assessed within a sample of 58 farms across the Seine-et-Marne region in France, using point counts and a standardised farmer survey. The local abundance of 41 farmland and non-farmland species was related to farming intensity (pesticide applications) and landscape simplification (proportion of arable land), which was quantified using generalised least square models to account for spatial autocorrelation. The more specialised the farmland and non-farmland birds were, the more negatively affected they were by the intensity of farming practices, relative to the generalist bird species. Local habitat simplification had a more positive effect on abundance of the most specialist farmland bird species. This latter relationship was not significant when tested at a landscape scale, which strongly suggests that the sensitivity of farmland specialists to landscape simplification is scale-dependent. Some non-farmland species’ abundance was also reduced by farming intensity and local landscape simplification suggesting that low-input agri-environmental measures could benefit both farmland and non-farmland specialists, regardless of local and landscape habitat context. However, if diversity-enhancing measures should benefit non-farmland populations, it is likely that they do not favour farmland specialist species which are more at risk. We suggest designing of priority areas for farmland specialist birds, and landscape managing accordingly. [Copyright &y& Elsevier]

The Conservation Reserve Program (CRP) has converted just over 36 million acres of cropland into potential wildlife habitat, primarily grassland. Thus, the CRP should benefit grassland songbirds, a group of species that is declining across the United States and is of conservation concern. Additionally, the CRP is an important part of multi-agency, regional efforts to restore northern bobwhite populations. However, comprehensive assessments of the wildlife benefits of CRP at regional scales are lacking. We used Breeding Bird Survey and National Resources Inventory data to assess the potential for the CRP to benefit northern bobwhite and other grassland birds with overlapping ranges and similar habitat associations. We built regression models for 15 species in seven different ecological regions. Forty-nine of 108 total models contained significant CRP effects ( P < 0.05), and 48 of the 49 contained positive effects. Responses to CRP varied across ecological regions. Only eastern meadowlark was positively-related to CRP in all the ecological regions, and western meadowlark was the only species never related to CRP. CRP was a strong predictor of bird abundance compared to other land cover types. The potential for CRP habitat as a regional conservation tool to benefit declining grassland bird populations should continue to be assessed at a variety of spatial scales. We caution that bird-CRP relations varied from region to region and among species. Because the NRI provides relatively coarse resolution information on CRP, more detailed information about CRP habitats (spatial arrangement, age of the habitat (time since planting), specific conservation practices used) should be included in future assessments to fully understand where and to what extent CRP can benefit grassland birds. [ABSTRACT FROM AUTHOR]

Abstract: In this study territory densities of field-breeding farmland birds were compared on pairwise-selected organic and conventional arable farms for two years. Differences in territory densities between the two farm types were explained examining the effects of three factors on territory densities: (1) non-crop habitats, (2) crop types and (3) within-crop factors. In both years, densities of most species did not differ between organic and conventional farms. Only skylark and lapwing were more abundant on organic farms, but only skylarks showed a consistent pattern over both years. Differences in crop types grown between the two systems were the only explaining factor for differences in densities of skylark. For lapwing, the difference was only partly due to differences in crop type, but differences in within-crop factors (probably as a result of crop management) were likely to have had an effect as well. There were no significant differences in abundance of non-crop habitats between the two farming systems, so this could not explain differences in territory densities. [Copyright &y& Elsevier]

Measuring edge effects in complex landscapes is often confounded by the presence of different kinds of natural and anthropogenic edges, each of which may act differently on organisms inhabiting habitat patches. In such landscapes, proportions of different habitats surrounding nests within patches often vary and may affect nesting success independently of distance to edges. We developed methods to measure and study the effects of multiple edges and varying habitat composition around nests on the breeding success of the Acadian flycatcher (Empidonax virescens), an understory, open-cup nesting songbird. The Kaskaskia River in Southwestern Illinois was our study area and consists of wide (>1000-m) floodplain corridors embedded in an agricultural matrix with a variety of natural (wide rivers, backwater swamps, and oxbow lakes) and anthropogenic (internal openings, and agricultural) habitats. We also measured vegetation structure around each nest. Nest survival increased with increasing nest concealment, and probabilities of brood parasitism increased with increasing distances from anthropogenic and natural water-related openings surrounding nests. The magnitude of these effects was small, probably because the landscape is saturated with nest predators and brood parasites. These results illustrate the importance of considering both larger landscape context and details of natural and anthropogenic disturbances when studying the effects of habitat fragmentation on wildlife. [ABSTRACT FROM AUTHOR]

Aim Factors acting at various scales may affect biodiversity, demanding analyses at multiple spatial scales in order to understand how community richness is determined. Here, we adopted a hierarchical approach to test the contribution of region, landscape heterogeneity, local management (organic vs. conventional) and location within field (edge vs. centre) to the species richness and abundance of spiders in cereals. Location Three regions of western and central Germany: Leine Bergland, Soester Boerde, and Lahn-Dill Bergland. Methods Forty-two paired organic and conventional winter wheat fields were compared. Field pairs were located in areas ranging from structurally simple to structurally complex landscapes. In May and June 2003, spiders were sampled using pitfall traps. Linear mixed models were used to determine the relationship of spider diversity and abundance with regional spatial factors and landscape heterogeneity within a 500-m radius, as well as with local management and within-field location . Results Within-field location of the traps and landscape heterogeneity were the best predictors of species richness: more species were found in field edges and in heterogeneous landscapes. Region and local management had no effect on species richness. Activity density was higher in field edges and differed among regions. Main conclusions The diversity of farmland spiders was influenced by differences at two of the spatial scales (edge vs. centre, simple vs. complex landscapes), but not at the two others (field management, region), emphasizing the importance of analyses at a variety of spatial scales for an adequate explanation of patterns in biodiversity. Our study suggests that promoting heterogeneity in land use at landscape scales is one of the keys to promoting spider diversity in agroecosystems. [ABSTRACT FROM AUTHOR]