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Heterostyly is a genetically determined floral polymorphism of style length promoting outcrossing between individuals of different morphs, which usually coexist within populations at equal frequencies. Loss in the area and connectivity of suitable habitats may cause deviations from the expected equal morph frequencies. However, there is a need to evaluate the generality of this pattern at larger spatial extents and to identify possible underlying mechanisms. A citizen‐science approach was used to study morph frequencies in populations of the heterostylous grassland plant Primula veris across Estonia. We developed an online platform to facilitate an easy upload of the data. We examined the effect of the following variables in the surroundings of the study populations reflecting the landscape context on the deviation of morph ratios: (a) semi‐natural grasslands, (b) forests and shrubs, (c) human population density and (d) a proxy for plant population size. The citizen‐science approach provided unprecedented density of data from 1,700 localities. Nearly half of these observations, which were maintained for further analysis after data filtering, included over 62,000 short‐styled morphs and about 54,000 long‐styled morphs. Small populations were characterized by higher overall deviation of morph ratios from isoplethy (equal morph ratio). Deviation increased in semi‐natural grasslands located in regions with high human population density. The significant effect of human population density and plant population size on deviations of morph frequencies suggests the role of stochastic demographic effects of habitat fragmentation on morph ratios. Overall lower proportion of long‐styled morphs indicates that partial intra‐morph compatibility shown in long‐styled morphs may lead to higher inbreeding and related decline in fitness and abundance. Synthesis. Citizen‐science data about the morph type of Primula veris across Estonia obtained with the help of thousands of people demonstrates that in addition to plant population size, landscape context may affect plant reproductive traits, such as heterostyly. Larger population size of P. veris can help to buffer against random fluctuations in this trait. Increasing impact of human activities may have a negative impact on both small and large populations. The exact underlying mechanisms of the prevalence of one morph over the other, however, pose novel questions for further research.

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

ispartof: Functional Ecology vol:35 issue:12 pages:1-14 status: Published online

Aim Habitat loss threatens plant diversity globally. Lack of plant functional connectivity between isolated populations is often pinpointed as one of the major underlying mechanisms driving subsequ ...

In the era of ongoing global change, it is highly important that restoration efforts lead to functioning, self-sustainable ecosystems that are resilient to disturbance and resistant to environmental changes. Therefore, it is necessary that restoration aims at achieving high genetic diversity of plant populations in addition to the recovery of characteristic species composition and diversity. Nevertheless, species- and gene-level biodiversity are rarely examined together in the context of restoration, although high genetic diversity of plant populations is a fundamental factor ensuring long-term success of restoration. Landscape-scale dispersal is the key process linked to the recovery of vegetation and maintaining both species and genetic diversity following restoration. In fragmented landscapes, dispersal of seeds and genetic material is often disrupted, leading to failure in spontaneous recovery of species richness as well as in establishment and maintenance of genetically diverse populations. Here, we review the linkages between landscape-scale dispersal of plants and the recovery of species richness and genetic diversity of plants during habitat restoration. We propose recommendations for restoration planners and practitioners to consider while aiming to restore self-sustainable ecosystems with high species- and gene-level biodiversity.

Wildflower seed mixtures are widely used for restoration of grasslands. However, the genetic and fitness consequences of using seed mixes have not been fully evaluated. Here, we studied the role of genetic diversity, origin (commercial regional seed mixtures, natural populations), and environmental conditions for the fitness of a grassland species Lychnis flos-cuculi. First, we examined the relationship between genetic diversity, environmental parameters, and fitness in sown and natural populations of this species in a Swiss agricultural landscape. Second, we established an experiment in the study area and in an experimental garden to study the implications of local adaptation for plant fitness. Third, to examine the response of plants to different soil properties, we conducted an experiment in climate chambers, where we grew plants from sown and natural populations of L. flos-cuculi as well as from seed suppliers on soils with different nutrient and moisture content. We detected no significant effect of genetic diversity on the fitness of sown and natural populations. There was no clear indication that plants from natural populations were better adapted to local environment than plants from sown populations or seed suppliers. However, plants of natural origin invested more into generative reproduction than plants from sown populations or seed suppliers. Furthermore, in the climate chamber, plants originating from natural populations tended to flower earlier. Our results indicate that using nonlocal seeds for habitat recreation may influence restoration success even if the seeds originate from the same seed zone as the restored site.

Summary The success of ecological restoration is often judged by the number and abundance of species, especially rare ones that have established since restoration. However, the effects of habitat improvement upon connectivity are rarely assessed, although this can readily be performed using modern molecular genetic methods. We evaluated the functional connectivity of populations of a wet grassland plant Lychnis flos-cuculi in an intensively managed agricultural landscape in Switzerland. One third of the study populations had been recently restored by sowing wildflower seed mixtures, while all other populations were of natural origin. We used assignment tests to identify first-generation migrants and to estimate recent patterns of gene flow among the populations of L. flos-cuculi. Assignment tests revealed higher levels of recent gene flow among natural populations of L. flos-cuculi than between sown and natural populations. Most probably, this result simply reflected the formerly good connectivity of natural populations in the study landscape. We detected a few first-generation migrants between sown and natural populations and among natural populations, suggesting that functional connectivity was now rather restricted. Migration among sown and natural populations was more likely to occur when natural and sown populations were nearby and when source populations were large. Synthesis and applications. We demonstrated that genetic methods offer a valuable tool for examining the effects of restoration measures on functional connectivity of plant populations. The connectivity of wet grasslands is likely to be best enhanced by establishing a relatively dense network of large habitat patches.

1. Organic farming in Europe has been shown to enhance biodiversity locally, but potential interactions with the surrounding landscape and the potential effects on ecosystem services are less well known. 2. In cereal fields on 153 farms in five European regions, we examined how the species richness and abundance of wild plants, ground beetles and breeding birds, and the biological control potential of the area, were affected by organic and conventional farming, and how these effects were modified by landscape complexity (percentage of arable crops within 1000 m of the study plots). Information on biodiversity was gathered from vegetation plots, pitfall traps and by bird territory mapping. The biological control potential was measured as the percentage of glued, live aphids removed from plastic labels exposed in cereal fields for 24 h. 3. Predation on aphids was highest in organic fields in complex landscapes, and declined with increasing landscape homogeneity. The biological control potential in conventional fields was not affected by landscape complexity, and in homogenous landscapes it was higher in conventional fields than in organic fields, as indicated by an interaction between farming practice and landscape complexity. 4. A simplification of the landscape, from 20% to 100% arable land, reduced plant species richness by about 16% and cover by 14% in organic fields, and 33% and 5·5% in conventional fields. For birds, landscape simplification reduced species richness and abundance by 34% and 32% in organic fields and by 45·5% and 39% in conventional fields. Ground beetles were more abundant in simple landscapes, but were unaffected by farming practice. 5. Synthesis and applications. This Europe-wide study shows that organic farming enhanced the biodiversity of plants and birds in all landscapes, but only improved the potential for biological control in heterogeneous landscapes. These mixed results stress the importance of taking both local management and regional landscape complexity into consideration when developing future agri-environment schemes, and suggest that local-regional interactions may affect other ecosystem services and functions. This study also shows that it is not enough to design and monitor agri-environment schemes on the basis of biodiversity, but that ecosystem services should be considered too.

Question: How distinct is the flora of field boundaries? How does the structure of field boundaries determine the composition of vegetation? Location: Estonia, six 4 km × 4 km agricultural areas. Methods: We studied the vegetation of fields and field boundaries using 2 m × 2 m sample plots. We estimated the frequency of species in both habitat types, applied an MRPP test to analyse the vegetation composition of field boundaries with various combinations of landscape features (ditches, roads, tree and bush layers) illustrating this by DCA ordination, and used indicator species analysis to determine the characteristic species of each boundary type. Results: Ca. 45% of the flora of field boundaries comprised species found on agricultural land. Most typical species in fields – agrotolerants – were also the most common in field boundaries. The vegetation of road verges and grassy boundaries consisted mainly of disturbance-tolerant species. Woody boundaries were characterised by shade-tolerant and nitr...