Surrounding Landscape Structure Research Articles

A multi-scale analysis on the importance of patch-surroundings for farmland birds

Agricultural intensification has profoundly changed agricultural landscapes with important biodiversity impacts. There is increasing knowledge on the general effects of landscape structure and management practices on plant and animal species but understanding the role of surrounding landscape structure for patch-scale biodiversity is more complex. While it can be reasonably assumed, that adjacent habitats are more important than more distant ones, the importance of landscape structure has often been tested at the landscape scale but rarely at smaller scales such as patch-surroundings. We assessed the influence and interdependences of landscape composition and configuration (LCC) and land use/land cover (LULC) on bird species richness and abundance through a multi-scale analysis with specific focus on the surrounding patches. In two agricultural regions in Switzerland, we collected point data of birds on 36 transects (500 m) and combined them with detailed spatial data on LULC. Bird richness and abundance were correlated to sets of landscape metrics as proxies for LCC computed at the transect-scale as well as for the patch surroundings. We analysed patch LULC as well as the most important patch-surrounding metrics using generalized linear mixed models. The results illustrate that patch LULC is the most important predictor of bird richness and abundance. Woody structures increase bird richness, followed by extensive management on patch scale. On the transect-scale semi-natural structure and heterogeneous LCCs are beneficial for bird richness and abundance. The effect of patch-surrounding structure LCCs is only small and interacts with patch LULC. Birds in grassland benefit from fallows in the surroundings, while in cropland they tend to respond positively to surrounding extensive grassland. Our results highlight that considering surroundings can help improve patch-based biodiversity assessments, which will then better predict the consequences of farmland management and make the outcome more applicable for practice.

Prays oleae (Bernard), its potential predators and biocontrol depend on the structure of the surrounding landscape

Arthropod populations from agricultural fields sometimes depend on the surrounding landscape structure, both composition and configuration, which affects multiple life-history traits of arthropods such as resources for survival, dispersion or death risk (e.g., predation or parasitism). Moreover, the effect of the landscape may vary with the distance to the crop, depending on factors such as the organism requirements and dispersion capabilities. This work addresses the effect of landscape (at five different scales from 250 to 1500 m) on the olive moth (Prays oleae Bernard, a key pest in olive orchards), some of its most relevant natural enemies, and biological control. The two-years study in 15 olive groves in southeastern Madrid, Spain shows that landscape complexity favours control of the olive moth, P. oleae. Simple landscapes favour P. oleae attack to the crop (measured as oviposition of the anthophagous generation) and that egg predation of the carpophagous generation is in some cases enhanced in complex landscapes. Lacewings (Neuroptera: Chrysopidae) are responsible for egg predation and populations increase in complex landscapes. On the other hand, the role of pirate bugs (Hemiptera: Anthocoridae) as a biological control agent of this part of the life cycle of P. oleae was not demonstrated. They respond primarily to Euphyllura olivina (Costa) (Hemiptera: Psyllidae) populations and are more abundant in simple landscapes. Most of the significant relationships of pest attack were detected at 750–1000 m radii buffers around the sampled olive groves suggesting that this is the main activity range for adults of P. oleae anthophagous generation. In sum, our results suggest complex configurations of the landscape enhance the biological control of P. oleae through favouring lacewings and egg predation of the carpophagous generation.

Strong relationships between urbanization, landscape structure, and ecosystem service multifunctionality in urban forest fragments

Urban forest fragments are highly multifunctional and provide many ecosystem services to people. However, the expansion and densification of cities is threatening this particular type of urban forest, resulting in further fragmentation, degradation and a change in forest function. Understanding how urbanization affects urban forests fragments and the multiple ecosystem services they provide is important for the creation of livable cities. We used an urban-to-rural gradient in Maple Ridge, Canada, to explore relationships between urban forest structure, urbanization, surrounding landscape structure, and the supply of eight different ecosystem services, including merchantable timber, carbon storage, flood control, food (berries), non-native shrub control, cultural use, and habitat provision. We found that the supply of multiple ecosystem services was higher at the rural end of our gradient and that forest fragments spaced closer together showed strong negative associations with most services. Crucially, forest fragment size had very weak effects on most services, emphasizing the importance of conserving small urban forest fragments with large trees. We also identified key tree genera, including Picea and Thuja, that could be retained or planted in urban forests to maximize individual services and multifunctionality. Our results highlight the potential for strategically managing urban landscapes to maintain forest fragments and enhance their ability to provide ecosystem services and multifunctionality. Our findings are relevant to inform urban conservation and greening strategies in cities around the world that are currently expanding into surrounding forests or losing greenspace through densification.

GIScience and Historical Cartography for Evaluating Land Use Changes and Resulting Effects on Carbon Balance

Multi-chronological examination of territory using GIScience and historical cartography may reveal a strategic tool for investigating changes in land use and the surrounding landscape structure. In this framework, the soil plays a key role in ecosystem evolution, since it governs all the mechanisms at the basis of vegetal growth, as well as all components of the total environment contributing to the formation of a rural landscape, including the balance of carbon dioxide. The present study was developed using a GIS approach applied to historical maps and aims to assess the environmental impact of land-use change, with particular attention to its effects on agricultural soil and atmospheric carbon dioxide balance. Thanks to a comparison between historical cartographic maps of different periods, this geospatial approach has enabled the assessment of the evolution of the rural land of the study area in the municipality of Ruoti (Basilicata Region—Southern Italy). This area, indeed, has been affected by deep land-use transformations, mainly caused by agricultural activities, with a resulting impact on the atmospheric CO2 balance. These transformations have been analyzed and quantified in order to contribute to the understanding on how the changes in land use for agricultural purposes have led to unforeseen changes in the rural landscape, ecosystems and the environment. The results showed that the greatest changes in land use were caused by the abandonment of large rural areas, resulting in the expansion of urban areas, a decrease in orchard and arable land (about less 25%), and an increase in woodland (more than 30%). These changes have resulted in a doubling in soil carbon fixation value. The final results have therefore confirmed that historical cartography within a GIS approach may decisively offer information useful for more sustainable agricultural activities, so as to reduce their negative contribution to climate change.

Responses of ground beetle (Coleoptera: Carabidae) assemblages to stand characteristics and landscape structure in riparian poplar forests

Abstract Many carabid beetles are among the most important biocontrol agents and are biological indicators of environmental change, although relatively little is known about how local and landscape factors affect forest ground beetle assemblages. Understanding such effects of multi‐scale environmental drivers on ground beetles can promote carabid diversity and conservation. Ground beetles were sampled by pitfall trapping in 40 poplar forest stands (sampling plots) along the Irtysh River in Northwestern China. We investigated responses of carabid activity density, species diversity and functional diversity (FD) to stand characteristics and surrounding landscape structure (the overall diversity and percentage cover of vegetation productivity classes in the surrounding area of each sampling plot based on normalised difference vegetation index). While carabid activity density only responded positively to the overall diversity of vegetation productivity classes, carabid species diversity was positively associated with this landscape factor as well as vegetation cover but negatively associated with the nearest distance from sampling plot to the river. Only carabid FD responded significantly to percentage cover of vegetation productivity classes, showing a positive correlation with the proportion of medium vegetation productivity. Furthermore, overall carabid FD declined with increasing tree canopy cover. Our results can help predicting spatial patterns of ground beetles according to landscape diversity and proportions of surrounding vegetation types and improve the design of conservation strategies (such as altering canopy cover) of carabids, especially forest specialist species. Any forest management strategies for promoting carabid diversity should consider the pervasive effects of landscape composition and configuration besides local stand characteristics.

Qualitative and Quantitative Loss of Habitat at Different Spatial Scales Affects Functional Moth Diversity

Land use change has led to large-scale insect decline, threatening ecosystem resilience through reduced functional diversity. Even in nature reserves, losses in insect diversity have been detected. Hereby, changes in local habitat quality and landscape-scale habitat quantity can play a role driving functional diversity toward erosion. Our aim was to analyze how local and landscape-scale factors simultaneously affect functional insect diversity. Therefore, we sampled moths in two Italian coastal forest reserves at 60 sites. Our focus was on functional richness, redundancy and niche occupation, being important for ecosystem resilience, following the insurance framework. Ecological information about 387 species and 14 traits was used to analyze functional diversity. Twenty-five functional groups were recognized and used to estimate niche occupation and redundancy. Fourteen local and 12 landscape-scale factors were measured and condensed by using Principal Components Analysis. The resulting PC-axes served as predictors in linear mixed effects models. Functional richness, redundancy and niche occupation of moths were lower at sites with low habitat quality and quantity, indicating reduced ecosystem resilience. Especially landscape diversity and habitat structure, viz. a humidity-nutrient gradient, but also plant diversity, were promoting functional richness. Landscape fragmentation, indicating increased impermeability for insects, reduced local functional richness, redundancy and niche occupation. Local habitat quality and landscape-wide habitat quantity are both important for maintaining functional insect diversity inside reserves. Therefore, small and isolated nature reserves might fail in preserving biodiversity and ecosystem functions through adverse effects acting from the surrounding landscape structure and configuration.

Which landscape and abiotic site factors influence vegetation succession across seres at a country scale?

AbstractQuestions(1) How much do abiotic site factors and land‐cover categories influence the course of succession across successional series at a country scale? (2) Are there any differences in the abiotic site factors and land‐cover categories which are responsible for driving primary and secondary seres? (3) Which of the factors influence species richness and participation of target species?LocationVarious disturbed sites in the Czech Republic, Central Europe.MethodsThe Database of Successional Series (DaSS) was compiled of 21 different types of succession, comprising 2,846 phytosociological relevés. The stages ranged from 1 to >150 years in age. Abiotic site factors included macroclimate characteristics and substrate; landscape factors comprised various land‐cover categories in a radius of 1 km around each sampled site. Principal Coordinate Analysis of Neighbour Matrices (PCNM) was performed to quantify the effect of abiotic site factors and landscape factors on seral vegetation, also regarding the primary or secondary status of succession. The relationships between number of species, number and proportion of target species and abiotic site and landscape factors were further assessed using generalised linear model analysis.ResultsAll considered abiotic and landscape factors were found to have significant effects on the course of succession. The effects of abiotic site factors appeared to be more important than those of the surrounding landscape structure. Species richness was higher on basic substrates. The proportion of target species increased with increasing woodland area in the surrounding and with a wetter and colder climate, and decreased with urbanisation rate of the landscape.ConclusionNot only local but landscape factors, such as climate and land cover, should be considered in any study of succession, as they substantially influence the general successional pattern. Quantification of the role of these environmental factors may help to decide where a spontaneous restoration is a viable option for the restoration of disturbed sites. The primary or secondary status of succession is less relevant than has usually been supposed.

Contentious eye-catchers: Perceptions of landscapes changed by solar power plants in Slovenia

While renewable energy sources enjoy high public support, projects are rarely implemented without opposition. The term energy landscapes indicates that landscape change is amongst the most frequent issues. This study researched lay people’s perceptions of landscapes changed by solar power plants. The first objective was to discover how likely solar power plants are to be noticed in the landscape. The second objective was to determine the associations observers make when spotting a solar power plant. The data was collected by participatory photography and focus groups. Participants visited six solar power plants. The results show that they are highly noticeable and contentious objects. Participants who understood the landscape as a rural idyll disapproved of solar power plants, while for those who perceived the landscape through a utilitarian narrative, the (mis)fit of the solar power plant depended on its relation to the surrounding landscape structure. Landscape degradation was contrasted with low-carbon energy and developmental benefits. The results provide evidence on the interdependence of visual and non-visual factors and suggest improvements in planning and design of solar power plants. While the method gives a rich in-depth insight into landscape perception, it is also context dependent and needs further research to obtain more generalisable results.

Landscape structure influences browsing on a keystone tree species in conservation areas

Aspen is a keystone species in boreal forests. The future of aspen in many conservation areas is threatened by ungulate browsing. Our aim was to study the effect of browsing on aspen regeneration and population structure in conservation areas in Central Finland, and the effect of surrounding landscape structure on browsing. Aspen density varied greatly among and within conservation areas. In about half of the conservation areas, middle-sized aspens were scarce or missing, which indicates heavy browsing in the recent past. In addition, the number of dead, large aspens in advanced decay stages were rare. Browsing pressure varied greatly among the areas, but on average, a bit more than half of the living aspens had been browsed. Landscape structure influenced browsing so that increasing proportion of farmland within 1 km and 3 km of the conservation areas decreased browsing pressure. The poor recruitment of aspen in many conservation areas jeopardizes the accumulation of large living and dead aspens. This means that many aspen-associated threatened species are in the risk of local extinction, unless aspen recruitment is enhanced by management.

Contrasting Effects of Tillage and Landscape Structure on Spiders and Springtails in Vineyards

Interactions between predatory species and their potential prey are little studied in vineyards, especially considering the surrounding landscape structure. We examined the effects of soil tillage intensities in vineyard inter-rows on the activity density and diversity of spiders (Araneae) and springtails (Collembola), their potential preys, and assessed whether these effects are altered by non-crop elements in the surrounding landscape. We collected data in 16 vineyards in Austria; eight were periodically mechanically disturbed (PMD), eight had permanent green cover (PGC). The study vineyards were embedded in landscapes ranging from structurally simple to complex. Both, spiders and springtails were collected with pitfall traps. Data analyses using generalized linear mixed models (GLMM) showed different effects of soil tillage intensities on spiders and springtails and an interaction with semi-natural elements (SNEs) in the surrounding landscape. Activities of springtails were higher under PMD than under PGC while spider activity density remained unaffected. Spider family Shannon diversity was lower under PMD than under PGC, while springtail species Shannon diversity was unaffected by tillage. Under PMD, spider activity and family diversity decreased with increasing SNEs in the surroundings indicating spider emigration away from vineyards. Under PGC, spider activity density increased with increasing SNE proportions in the surroundings when springtail activity density was high. Our findings suggest that recommendations on sustainable vineyard management should include both site and landscape factors.

Effects of landscape structure and temporal habitat dynamics on wintering mallard abundance

Management of wintering waterfowl in North America requires adaptability because constant landscape and environmental change challenges existing management strategies regarding waterfowl habitat use at large spatial scales. Migratory waterfowl including mallards (Anas platyrhynchos) use the lower Mississippi Alluvial Valley (MAV) for wintering habitat, making this an important area of emphasis for improving wetland conservation strategies, while enhancing the understanding of landscape-use patterns. We used aerial survey data collected in the Arkansas portion of the MAV (ARMAV) to explain the abundance and distribution of mallards in relation to variable landscape conditions. We used two-stage, hierarchical spatio-temporal models with a random spatial effect to identify covariates related to changes in mallard abundance and distribution within and among years. We found distinct spatio-temporal patterns existed for mallard distributions across the ARMAV and these distributions are dependent on the surrounding landscape structure and changing environmental conditions. Models performing best indicated seasonal surface water extent, rice field, wetland and fallow (uncultivated) fields positively influenced mallard presence. Rice fields, surface water and weather were found to influence mallard abundance. Additionally, the results suggest weather and changing surface water affects mallard presence and abundance throughout the winter. Using novel datasets to identify which environmental factors drive changes in regional wildlife distribution and abundance can improve management by providing managers additional information to manage land over landscapes spanning private and public lands. We suggest our analytical approach may be informative in other areas and for other wildlife species.

Flight morphology corresponds to both surrounding landscape structure and local patch conditions in a highly specialized peatland butterfly (Lycaena epixanthe)

1. Movement mediates the response of populations and communities to landscape and habitat spatial structure, yet movement capability may itself be modified by selection pressures accompanying landscape change. Insect flight morphology can be affected by both the landscape surrounding habitat patches and the distribution of resources within habitat patches.2. This study investigated the relative influence of local habitat patch conditions and surrounding landscape structure on variation in morphological traits associated with flight in the bog copper (Lycaena epixanthe), a butterfly endemic to temperate Nearctic peatlands.3. Eight habitat patches were sampled to assess the influence of the surrounding landscape (connectivity of potential habitat and matrix composition) and patch size (an integrated proxy of resource density and spatial distribution) on investment into flight, measured by thorax and abdomen mass, and wing area.4. The results revealed an effect of both local habitat conditions and landscape structure on flight‐related morphological traits. Increasing forest cover in the surrounding landscape, indicative of increased habitat patch isolation, corresponded with less mobile phenotypes in both sexes. Surrounding landscapes with more water were also generally associated with less mobile phenotypes. Investment into flight was greater in smaller peatlands in which host plant density is higher and more homogeneously distributed.5. The present study highlights that morphological traits associated with mobility may be responding to both local habitat patch characteristics and surrounding landscape structure. It also supports the hypothesis that local habitat conditions contribute to morphological variation in butterflies.

Landscape Effects on Reproduction of Euschistus servus (Hemiptera: Pentatomidae), a Mobile, Polyphagous, Multivoltine Arthropod Herbivore.

Landscape factors can significantly influence arthropod populations. The economically important brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), is a native mobile, polyphagous and multivoltine pest of many crops in southeastern United States and understanding the relative influence of local and landscape factors on their reproduction may facilitate population management. Finite rate of population increase (λ) was estimated in four major crop hosts-maize, peanut, cotton, and soybean-over 3 yr in 16 landscapes of southern Georgia. A geographic information system (GIS) was used to characterize the surrounding landscape structure. LASSO regression was used to identify the subset of local and landscape characteristics and predator densities that account for variation in λ. The percentage area of maize, peanut and woodland and pasture in the landscape and the connectivity of cropland had no influence on E. servus λ. The best model for explaining variation in λ included only four predictor variables: whether or not the sampled field was a soybean field, mean natural enemy density in the field, percentage area of cotton in the landscape and the percentage area of soybean in the landscape. Soybean was the single most important variable for determining E. servus λ, with much greater reproduction in soybean fields than in other crop species. Penalized regression and post-selection inference provide conservative estimates of the landscape-scale determinants of E. servus reproduction and indicate that a relatively simple set of in-field and landscape variables influences reproduction in this species.

Amphibian and reptile road-kills on tertiary roads in relation to landscape structure: using a citizen science approach with open-access land cover data

BackgroundAmphibians and reptiles are among the most endangered vertebrate species worldwide. However, little is known how they are affected by road-kills on tertiary roads and whether the surrounding landscape structure can explain road-kill patterns. The aim of our study was to examine the applicability of open-access remote sensing data for a large-scale citizen science approach to describe spatial patterns of road-killed amphibians and reptiles on tertiary roads. Using a citizen science app we monitored road-kills of amphibians and reptiles along 97.5 km of tertiary roads covering agricultural, municipal and interurban roads as well as cycling paths in eastern Austria over two seasons. Surrounding landscape was assessed using open access land cover classes for the region (Coordination of Information on the Environment, CORINE). Hotspot analysis was performed using kernel density estimation (KDE+). Relations between land cover classes and amphibian and reptile road-kills were analysed with conditional probabilities and general linear models (GLM). We also estimated the potential cost-efficiency of a large scale citizen science monitoring project.ResultsWe recorded 180 amphibian and 72 reptile road-kills comprising eight species mainly occurring on agricultural roads. KDE+ analyses revealed a significant clustering of road-killed amphibians and reptiles, which is an important information for authorities aiming to mitigate road-kills. Overall, hotspots of amphibian and reptile road-kills were next to the land cover classes arable land, suburban areas and vineyards. Conditional probabilities and GLMs identified road-kills especially next to preferred habitats of green toad, common toad and grass snake, the most often found road-killed species. A citizen science approach appeared to be more cost-efficient than monitoring by professional researchers only when more than 400 km of road are monitored.ConclusionsOur findings showed that freely available remote sensing data in combination with a citizen science approach would be a cost-efficient method aiming to identify and monitor road-kill hotspots of amphibians and reptiles on a larger scale.

Evaluating conceptual models of landscape change

A variety of landscape models are used to conceptualize and interpret human impacts on ecosystems and their biodiversity. The simplest, a ‘patch‐matrix’ model, is rooted in island biogeography theory and assumes a dichotomy between generic, easily‐defined habitat patches and a surrounding matrix that is completely inhospitable. This dichotomy between patch and matrix habitats has been recently relaxed, with the ‘continuum’ model taking this relaxation to its extreme and logical endpoint – a species‐based model with no a priori definition of habitat or matrix, but rather focusing on ecological gradients. Yet, because few empirical comparisons of these bookending models exist, we lack understanding of their relative utility or the merits of hybrid approaches that combine attributes of patch‐matrix and continuum models. To guide such considerations, we first develop a decision‐making framework for the application of patch‐matrix, continuum, and hybrid models. The framework takes into account study objectives, attributes of the landscape, and species traits. We then evaluate this framework by empirically comparing how continuum, patch‐matrix, and hybrid models explain beetle distributions across two contrasting fragmented landscapes, for species differing in trophic level and habitat specificity. Within the Hope River Forest Fragmentation Project, a system with strong landscape contrast and distinct (‘hard’) structural edges between forest fragments and grassland, we find broad support for hybrid models, particularly those incorporating surrounding landscape structure. Conversely, within the Wog Wog Habitat Fragmentation Experiment, a system with weak landscape contrast and ‘soft’ structural edges between natural and plantation forest, we find co‐support for continuum and hybrid models. We find no support in either system for patch‐matrix, relative to continuum and hybrid models. We conclude by considering key questions and areas of research for advancing the application of models to understand species responses and biodiversity patterns associated with land‐use change.

Very high resolution Earth Observation features for testing the direct and indirect effects of landscape structure on local habitat quality

Modelling the empirical relationships between habitat quality and species distribution patterns is the first step to understanding human impacts on biodiversity. It is important to build on this understanding to develop a broader conceptual appreciation of the influence of surrounding landscape structure on local habitat quality, across multiple spatial scales. Traditional models which report that ‘habitat amount’ in the landscape is sufficient to explain patterns of biodiversity, irrespective of habitat configuration or spatial variation in habitat quality at edges, implicitly treat each unit of habitat as interchangeable and ignore the high degree of interdependence between spatial components of land-use change. Here, we test the contrasting hypothesis, that local habitat units are not interchangeable in their habitat attributes, but are instead dependent on variation in surrounding habitat structure at both patch- and landscape levels. As the statistical approaches needed to implement such hierarchical causal models are observation-intensive, we utilise very high resolution (VHR) Earth Observation (EO) images to rapidly generate fine-grained measures of habitat patch internal heterogeneities over large spatial extents. We use linear mixed-effects models to test whether these remotely-sensed proxies for habitat quality were influenced by surrounding patch or landscape structure. The results demonstrate the significant influence of surrounding patch and landscape context on local habitat quality. They further indicate that such an influence can be direct, when a landscape variable alone influences the habitat structure variable, and/or indirect when the landscape and patch attributes have a conjoined effect on the response variable. We conclude that a substantial degree of interaction among spatial configuration effects is likely to be the norm in determining the ecological consequences of habitat fragmentation, thus corroborating the notion of the spatial context dependence of habitat quality.

THE ROLE OF SURROUNDING LANDSCAPE IN DETERMINING SPECIES RICHNESS OF MESIC GRASSLANDS IN PANNONIAN BASIN AND CARPATHIAN MOUNTAINS

Alpha diversity of mesic grasslands of the Arrhenatheretalia order was related to the surrounding landscape structure. The following questions were addressed: i) Does structure of surrounding landscape affect local species richness? How important is the influence of surrounding landscape in comparison with influence of climatic-topographical and soil-geological variables? ii) Do the landscape effects differ in climatically distinct regions (Pannonian, Carpathian colline-submontane and Carpathian montane-subalpine)? iii) Which of the surrounding habitats contribute to species richness and which species immigrate to grasslands most frequently? Species data were extracted from Slovak vegetation plot database. Surrounding land-use (in terms of cover and diversity of various habitat types in plot neighbourhood of 4 km) was derived from CORINE land cover maps and National Grassland Inventory. Both, percentage cover and diversity of different habitat types in plot neighbourhood affected local species richness. In the Pannonian Basin, mesic grasslands had the lowest species richness but the landscape factors explained the highest proportion of its variance. In the montane-subalpine Carpathian region, the effect of landscape factors was least pronounced. The surrounding landscape affected number, proportion and cover of satellite species in plots. Mesic grasslands of the Pannonian Basin hosted the largest number, proportion and cover of archaeophytes and neophytes.

Non-linear responses of functional diversity and redundancy to agricultural intensification at the field scale in Mediterranean arable plant communities

Despite their key roles in agroecosystems, species diversity of arable plants is being severely reduced by agricultural intensification, although it remains unclear whether functional diversity is affected in a similar way. We analyzed the response of four functional traits of arable plants (specific leaf area, canopy height, seed mass and flowering onset) to agricultural intensification in Mediterranean arable plant communities. Two intensification gradients were obtained by PCA analysis on variables related either to management practices at the individual field scale or to the surrounding landscape structure and composition. Shifts in the community weighted mean (CWM) and the functional diversity (FD) of each trait along these intensification gradients were explored. The relationship between species richness and the FD of each trait (i.e. functional redundancy) along the same gradients was also analyzed. The responses of species richness and the considered functional traits were driven by intensification at the individual field scale, but not by intensification at the scale of the surrounding landscape. Species richness and FD of all the studied traits decreased with intensification, which favoured tall, heavy-seeded and early flowering species. The decrease of FD was non-linear for specific leaf area and seed mass, with maximum reductions at intermediate levels of intensification. Species richness and FD responses were decoupled, indicating that the functional redundancy in the studied communities responds to agricultural intensification in a non-linear fashion. Along the first stages of intensification, there was an important reduction in species richness that was not accompanied by changes in FD. Further levels of intensification resulted in substantial reductions in FD without changes in species richness. These findings provide new insights on how agricultural management interacts with plant communities through its non-linear effects on functional diversity and functional redundancy.

Response of farmland biodiversity to the introduction of bioenergy crops: effects of local factors and surrounding landscape context

AbstractThe recent growth in bioenergy crop cultivation, stimulated by the need to implement measures to reduce net CO2 emissions, is driving major land‐use changes with consequences for biodiversity and ecosystem service provision. Although the type of bioenergy crop and its associated management is likely to affect biodiversity at the local (field) scale, landscape context and its interaction with crop type may also influence biodiversity on farms. In this study, we assessed the impact of replacing conventional agricultural crops with two model bioenergy crops (either oilseed rape Brassica napus or Miscanthus × giganteus) on vascular plant, bumblebee, solitary bee, hoverfly and carabid beetle richness, diversity and abundance in 50 sites in Ireland. We assessed whether within‐field biodiversity was also related to surrounding landscape structure. We found that local‐ and landscape‐scale variables correlated with biodiversity in these agricultural landscapes. Overall, the differences between the bioenergy crops and the conventional crops on farmland biodiversity were mostly positive (e.g. higher vascular plant richness in Miscanthus planted on former conventional tillage, higher solitary bee abundance and richness in Miscanthus and oilseed rape compared with conventional crops) or neutral (e.g. no differences between crop types for hoverflies and bumblebees). We showed that these crop type effects were independent of (i.e. no interactions with) the surrounding landscape composition and configuration. However, surrounding landscape context did relate to biodiversity in these farms, negatively for carabid beetles and positively for hoverflies. Although we conclude that the bioenergy crops compared favourably with conventional crops in terms of biodiversity of the taxa studied at the field scale, the effects of large‐scale planting in these landscapes could result in very different impacts. Maintaining ecosystem functioning and the delivery of ecosystem services will require a greater understanding of impacts at the landscape scale to ensure the sustainable development of climate change mitigation measures.

Landscape effects on diversity of semi-natural grasslands

We studied how the landscape structure (percentage cover and diversity of surrounding habitats) affects different components of species diversity (alpha, beta and gamma) of vascular plants in semi-natural grasslands in the Slovak Republic. We analyzed all grasslands combined as well as four main types delimited according to their position along a moisture gradient (xerophilous, sub-xerophilous, mesophilous and wet grasslands). We used grassland records stored in the Slovak Vegetation Database. The geographically stratified dataset included 3795 plots with 1221 species of vascular plants. Along with the total number of species in the vegetation plots, we considered the numbers of target grassland species, forest species, archaeophytes, neophytes and species with high fidelity to non-natural habitats. The landscape parameters based on CORINE land cover maps and the National Grassland Inventory, were calculated for plot neighbourhoods of 4km2. Spatially constrained rarefaction curves were constructed to examine how different diversity components behave with changing structure of the surrounding landscape. Our study revealed that alpha diversity was affected by both percentage cover and diversity of different habitats in the plot neighbourhood. It increased with increasing proportion or diversity of different natural and semi-natural habitats and decreased with increasing proportion or diversity of non-natural habitats in the surrounding landscape. Beta and gamma diversities showed opposite pattern to that of alpha diversity for most analyzed factors. Alpha diversity in sub-xerophilous and mesophilous grasslands was more susceptible to changes in landscape structure than alpha diversity in xerophilous or wet grasslands. Regression trees and linear or quadratic regression models revealed that in xerophilous or wet grasslands, high alpha diversity was best predicted by a high proportion of ecologically valuable grasslands in the surroundings. In sub-xerophilous and mesophilous grasslands, the best predictor was proportion of natural and semi-natural habitats followed by the proportion of non-natural habitats. The detected pattern regarding alpha, beta and gamma diversity calculated for grassland target species did not differ from the pattern for the whole species assemblage. However, the surrounding landscape affected the number, proportion and cover of species typical of forest or non-natural habitats (including alien species) in the plots. We explain the results by the interplay of two main mechanisms: species pool and spatial mass effects. In our study, the effect of species pool on alpha diversity was stronger than the spatial mass effect. Based on differences indicated in the responses of various grassland types to the surrounding landscape structure, we suggest adoption of community type specific conservation measures