Habitat fragmentation increases the proportion of forest borders in the landscape and many forest borders lose their structural complexity due to modern forestry practices. However, remnants of structurally complex deciduous forests can remain as ecotones between plantations and agricultural fields. In this study we used terrestrial laser scanning to measure structural complexity of different forest borders, measured microclimate, and surveyed bats and macro-moths to understand how these taxa are affected. Our aim is to disentangle the main drivers, direct or indirect, that influence bat and moth assemblages. We studied 79 forest borders, and surrounding landscapes and compared them with adjacent agricultural fields and coniferous plantations. Overall, we found less bat activity and lower macro-moth diversity in simple compared to complex borders. Using structural equation modelling, we show the contrasting responses of forest-specialist bats and moths to structural complexity; with bats responding positively and moths negatively. We found similar divergent results in relation to understorey openness; with increasing forest-specialist bat activity but a lower diversity of forest-specialist moths in more open borders. Understorey vegetation also appears to regulate microclimate with more open borders being warmer and less humid. This has a potential knock-on effect for bats as they favoured borders that were warmer and more humid. Surrounding land-cover was more important than structural complexity for generalist species; with increasing generalist bat activity due to a higher proportion of local deciduous forest cover and increasing generalist moth diversity in landscapes with more forest borders. Overall, these complex relationships between forest structure, microclimate and landscape factors, coupled with divergent responses of both taxa highlight their diverse ecological needs. Therefore, we highlight the importance of managing forest borders to retain complexity and connectivity within multifunctional landscapes.

1. Agricultural intensification, afforestation and land abandonment are major drivers of biodiversity loss in semi-natural grasslands across Europe. Reversing these losses requires the reinstatement of plant–animal interactions such as pollination. Here we assessed the differences in species composition and patterns of plant-pollinator interactions in ancient and restored grasslands and how these patterns are influenced by landscape connectivity, across three European regions (Belgium, Germany and Sweden).
2. We evaluated the differences in pollinator community assemblage, abundance and interaction network structure between 24 ancient and restored grasslands. We then assessed the effect of surrounding landscape functional connectivity (i.e. green infrastructure, GI) on these variables and tested possible consequences on the reproduction of two model plants, Lotus corniculatus and Salvia pratensis.
3. Neither pollinator richness nor species composition differed between ancient and restored grasslands. A high turnover of interactions across grasslands was detected but was mainly due to replacement of pollinator and plant species. The impact of grassland restoration was consistent across various pollinator functional groups, whereas the surrounding GI had differential effects. Notably, bees, butterflies, beetles, and dipterans (excluding hoverflies) exhibited the most significant responses to GI variations. Interestingly, networks in restored grasslands were more specialised (i.e. less functionally redundant) than in ancient ones and also showed a higher number of insect visits to habitat-generalist plant species. Landscape connectivity had a similar effect, with habitat-specialist plant species receiving fewer visits at higher GI values.
4. Fruit set in S. pratensis and L. corniculatus was unaffected by grassland type or GI. However, the fruit set in the specialist S. pratensis increased with the number of pollinator visits, indicating a positive correlation between pollinator activity and reproductive success in this particular species.
5. Synthesis and applications. Our findings provide evidence of the necessity to enhance ecosystem functions while avoiding biotic homogenisation. Restoration programs should aim at increasing landscape connectivity which influences plant communities, pollinator assemblages and their interaction patterns. To avoid generalist species taking over from specialists in restored grasslands, we suggest reinforcing the presence of specialist species in the latter, for instance by means of introductions, as well as increasing the connectivity to source populations.

In recent years, restoration on former grassland sites has been widely encouraged globally, aiming to address the historical loss of 90% of ancient species-rich grasslands, and to mitigate the associated threat to grassland biodiversity. The objective of our study was to investigate on a small-scale how plant species spontaneously colonize restored grasslands. We inventoried 275 permanent plots twice (in 2019 and 2021) in a restored grassland, following the removal of a conifer plantation. Species richness and vegetation cover in surveyed plots were dependent on grazing activity and distance to adjacent grassland. Plant species associated with forest habitats declined, while the occurrence of generalist species together with a few grassland specialists generally increased. However, not all grassland specialists gained occurrence and the colonization pattern was not consistent over time, possibly due to the lack of continuous seed arrival and low livestock activity and hence lack of disturbance. These results suggest that successful colonization of plant species benefits from links to species-rich sites adjacent to the restoration target, with spatial dispersal and improved conditions for species establishment being key to species occurrence. Both dispersal and establishment potential are likely facilitated through the presence of grazing livestock with access to both species-rich grasslands and restoration targets. However, the shift towards a more typical grassland community takes place gradually, with vulnerable populations of early colonizing grassland species prone to local extinction in short-term. As a result, continued functional connectivity provided by grazing animals is necessary to improve the diversity of the restored site and ensure the establishment of grassland specialists and to maintain the plant community composition.

Questions: Baltic coastal meadows are ecologically unique habitats that have been severely impacted by habitat loss and environmental change. To determine the effects of habitat loss and isolation on their plant communities, we analysed the relationships between species richness and habitat size and amount. Because coastal meadows host species with a vast array of traits, we expected responses to vary between species groups. Location: Swedish Baltic coast. Methods: We inventoried the presence of vascular plant species in twenty-eight 1-m2 plots placed along edaphically defined transects in fifteen coastal meadows. We determined the richness of three species groups: all species, halophytes and inland grassland specialists. We then mapped the habitat for coastal grassland plants using GIS overlay analysis. Using this habitat map, we calculated two variables: “habitat size” and “habitat amount”. We tested correlations between species richness measures and habitat variables, as well as determining the distribution of species traits within meadows. Results: We recorded 174 plant species, of which 6 were halophytes and 35 were inland grassland specialists. Species traits coincided with edaphic sea-to-land gradients. Halophyte and inland grassland specialist richness were significantly correlated with both habitat variables (r = 0.52–0.71). No correlations were found with total species richness. Our habitat map showed that there are 8,900 ha of managed Baltic coastal meadow left in Sweden, mostly in the south. Conclusions: Species traits and distribution play a major role in determining persistence in the face of habitat loss and environmental change. This is especially true for some halophyte populations, which are more susceptible to habitat size and isolation because of their specialisation. Furthermore, they risk being squeezed between the dual threats of encroaching succession and sea-level rise. Preventing habitat loss, restoring meadows and increasing connectivity is crucial for the persistence of specialist plant species.

Understanding the establishment of plant species is important to inform management of restored grasslands and to preserve biodiversity in ancient grasslands. In grassland communities, plant species can establish from seeds arriving via spatial dispersal, from seeds in the soil seed bank or through vegetative spread from nearby source individuals. However, this colonization potential and the likelihood of species establishment can vary in grasslands with different land-use history. We investigated the relative importance of local species recruitment sources, such as dispersal in space and time and species presence in adjacent grasslands, in determining establishment of plant species in eight grasslands with different land-use history (paired ancient grasslands continuously managed as pasture vs. restored grasslands on former forest). At each grassland, we established plots (0.25 m2) to monitor seedling emergence from seed dispersal, seed bank, and recorded clonal growth over two growing periods. We found that the likelihood of species establishment was highest from local seed rain, and that species present in the local species pool were more able to germinate and establish in both type of grasslands. Species from the seed bank and clonal growth contributed to a lesser extent to species establishment, but represented a greater proportion of the recolonization and regeneration of species in ancient grasslands. These results demonstrate that surrounding grasslands serve as a source for colonizing species and that dispersal from the adjacent grasslands is the key process in regeneration and colonization of plants. These results imply that the recovery of grasslands depends heavily upon to links to species source in grasslands, especially in restored grasslands. Therefore, management plans should incorporate rotational livestock grazing and larger networks of grassland in restoration efforts, which will enable to desirable species to establish and persist in grasslands.

Ancient semi-natural grasslands in Europe are important for ecosystem service (ES) provision. Often, the surrounding matrix contains ‘Grassland Green Infrastructure’ (GGI) that contain grassland species which have the potential to supplement grassland ES provision across the landscape. Here we investigate the potential for GGI to deliver a set of complementary ES, driven by plant composition.We surveyed 36 landscapes across three European countries comprising core grasslands and their surrounding GGI. We calculated community-level values of plant species characteristics to provide indicators for four ES: nature conservation value, pollination, carbon storage and aesthetic appeal.Inferred ES delivery for GGI was substantially lower than in core grasslands for conservation, pollination and aesthetic appeal indicators, but not for carbon storage. These differences were driven by the GGI having 17% fewer plant species, and compositional differences, with 61% of species unique to the core grasslands. In addition, connectivity to the core, the amount of GGI and inferred seed dispersal distances by livestock, were strongly positively correlated with conservation value, pollination and aesthetic indicators. All ES indicators showed similar responses to the GGI spatial structure and distance to the core, suggesting robust effects of these drivers on ES. We projected that improved landscape-wide delivery of nature conservation value and pollination could be achieved through targeted GGI management. Reductions in the distances seeds would need to disperse, more GGI, along with a diversification of the GGI elements, were predicted to enhance service credits.We conclude that for vegetation-related ES, species surveys can be employed to assess potential ES delivery. Creating and enhancing GGI is a useful landscape management strategy to supplement the ES delivered by ancient grasslands.

Background: Winters are expected to warm more than summers in central and northern Europe, with largely unknown effects on grassland plant communities.

Aims: By studying the interactions between winter warming and summer grazing, we aimed to disentangle their effects and give recommendations for future grassland management.

Methods: Our study area Upper Teesdale, England has winter temperatures close to 0°C and a well-studied vegetation, known for its arctic-alpine species growing at their climatic warm range limits. We set up a winter warming experiment using open top chambers (ca. +0.5°C) from mid-September until mid-May 2019 to 2022 and excluded sheep grazing during summer in a fully factorial design.

Results: Graminoid biomass increased, and bryophyte biomass decreased with winter warming. There was little to no evidence that winter warming affected any of the other plant response variables we measured, neither did grazing nor the interaction between winter warming and grazing.

Conclusions: Our experiment was relatively short in duration and treatments were realistic in magnitude, therefore the plant communities responded only slightly. Nevertheless, our data suggest a change towards more dominant vascular species and less bryophytes with winter warming, which might lead to lasting changes in the plant communities in the longer-term if not buffered by suitable grazing management.

1. One of the main reasons why insect pollinators are declining is a lack of floral resources. In agricultural landscapes, remaining seminatural grasslands play a key role for providing such resources. However, droughts pose an increasing threat to the abundance and continuity of flowers. Soil amendments are a novel management tool for Swedish grasslands aiming to increase carbon sequestration and soil water holding capacity. In this study, we examined how drought is affecting floral resources (i.e. floral units, nectar quantity and nectar continuity) in grasslands with different mowing regimes, and if soil amendments could mitigate potential negative drought effects.
2. In summer 2019, we set up an experiment combining rain-out shelters (‘drought’), soil amendments (‘compost’) and different mowing regimes (‘mown’ vs. ‘abandoned’) in four extensively managed Swedish grasslands (48 plots, size 2 m²). Between May and August 2021, we counted the floral units nine times in each plot. We derived values for the nectar sugar production per floral unit from an existing database.
3. We observed a decrease in floral units under drought in the mown, but not in the abandoned plots. Nectar quantity and continuity over the season were not significantly affected by drought across both mowing regimes—in the abandoned plots the nectar provision even extended slightly in duration (towards late summer). The compost treatment had positive effects on the floral units, nectar quantity and continuity (extending it towards early summer) in the mown, but not in the abandoned plots. The plant species in our study reacted differently to the treatments. Most of the nectar was provided by only few species (mainly Lathyrus pratensis, Vicia cracca and Anthriscus sylvestris).
4. The results are species specific, thus other plant communities might respond differently. However, our experiment shows that nectar provision (based on database values) in grasslands with a native plant community and natural soil conditions remains relatively stable under drought. We also found that soil amendments increase floral resources in managed grasslands.

Species may benefit from green infrastructure, i.e. the network of natural and anthropogenic habitat remnants in human-dominated landscapes, if it helps isolated populations in remaining habitat patches to be functionally connected. The importance of green infrastructure is therefore increasingly emphasized in conservation policy to counter biodiversity loss. However, there is limited evidence, particularly in plants, that green infrastructure promotes functional connectivity, i.e. supports the colonization of habitat patches across a landscape. We applied landscape genetics to test whether the green infrastructure supports structural and functional connectivity in the grassland perennial Galium verum, in 35 landscapes in Belgium, Germany and Sweden. We used multivariate genetic clustering techniques, nestedness analyses and conditional inference trees to examine landscape-scale patterns in genetic diversity and structure of plant populations in the green infrastructure surrounding semi-natural grasslands. Inferred functional connectivity explained genetic variation better than structural connectivity, yielding positive effects on genetic variation. The road verge network, a major structural component of the green infrastructure and its functional connectivity, most effectively explained genetic diversity and composition in G. verum. Galium verum ramets occupying the surrounding landscape proved to be genetic subsets of focal grassland populations, shaping a nested landscape population genetic structure with focal grasslands, particularly ancient ones, harbouring unique genetic diversity. This nested pattern weakened as road network density increased, suggesting road verge networks enable high landscape occupancy by increased habitat availability and facilitates gene flow into the surrounding landscape. Our study proposes that green infrastructure can promote functional connectivity, providing that a plant species can survive outside of core habitat patches. As this often excludes habitat specialist species, conservation practice and policy should primarily focus on ancient, managed semi-natural grasslands. These grasslands both harbour unique genetic diversity and act as primary gene and propagule sources for the surrounding landscape, highlighting their conservation value.

Semi-natural grasslands harbour many of Europe's species of conservation interest. Although larger grasslands are the focus of most conservation activity, many grassland fragments are scattered across landscapes –in small patches or along linear elements– which can form Grassland Green Infrastructure (GGI). GGI has the potential to enhance landscape diversity by creating functioning metacommunities comprising of large semi-natural grasslands and these surrounding fragments. While often highlighted in conservation policy, little is known about the biodiversity supported by green infrastructure itself and thus its conservation potential.

To address this issue, we contrasted plant communities in 36 ‘core’ grassland sites across three European countries with communities in the surrounding GGI. We related compositional differences to amount and type of GGI habitat (patches or linear), and the distances for seed dispersal by livestock from core sites. We found substantial differences between the GGI and the core sites, with a mean 54% species turn-over. These differences indicated filtering of stress tolerant species characteristic of low nutrient conditions, and semi-natural grassland specialists. Species with poorer dispersal abilities declined strongly with increasing distances from the core sites. The many additional species in the GGI, not found in the core sites, were predominantly those with a competitive strategy and high seed dispersal ability.

We conclude that the biodiversity-supporting role of GGI across Europe is severely constrained by eutrophication, dispersal limitation and external propagule pressure. Actions to improve the quality of GGI might include enhancing dispersal by livestock combined with more type-diversification and less intensively used grassland habitats.