Wild bee and floral diversity co-vary in response to the direct and indirect impacts of land use

Loss of habitat area and diversity poses a threat to communities of wild pollinators and flowering plants in agricultural landscapes. Pollinators, such as wild bees, and insect‐pollinated plants are two groups of organisms that closely interact. Nevertheless, it is still not clear how species richness and functional diversity, in terms of pollination‐relevant traits, of these two groups influence each other and how they respond to land use change. In the present study, we used data from 24 agricultural landscapes in seven European countries to investigate the effect of landscape composition and habitat richness on species richness and functional diversity of wild bees and insect‐pollinated plants. We characterized the relationships between the diversity of bees and flowering plants and identified indirect effects of landscape on bees and plants mediated by these relationships. We found that increasing cover of arable land negatively affected flowering plant species richness, while increasing habitat richness positively affected the species richness and functional diversity of bees. In contrast, the functional diversity of insect‐pollinated plants (when corrected for species richness) was unaffected by landscape composition, and habitat richness showed little relation to bee functional diversity. We additionally found that bee species richness positively affected plant species richness and that bee functional diversity was positively affected by both species richness and functional diversity of plants. The relationships between flowering plant and bee diversity were modulated by indirect effects of landscape characteristics on the biotic communities. In conclusion, our findings demonstrate that landscape properties affect plant and bee communities in both direct and indirect ways. The interconnection between the diversities of wild bees and insect‐pollinated plants increases the risk for parallel declines, extinctions, and functional depletion. Our study highlights the necessity of considering the interplay between interacting species groups when assessing the response of entire communities to land use changes

Vegetation Re-development After Fen Meadow Restoration by Topsoil Removal and Hay Transfer

We investigated the effects of different restoration treatments on the development of fen meadow communities: (1) depth of topsoil removal, with shallow (circa 20 cm) and deep (circa 40 cm) soil removal applied, (2) transfer of seed-containing hay, and (3) access of large animals. We carried out a full factorial experiment with all combinations of these factors and monitored it for 4 years. We studied the effect of seed availability in the soil seed bank on species abundance in the vegetation and compared it to the effect of species introduction by hay. We observed large differences in species composition between different treatments after 4 years. The combination of hay transfer, deep soil removal, and exclusion of large animals resulted in a community with highest similarity to the target vegetation. We found that the transfer of seeds with hay had a larger effect on species abundance than the soil seed bank. Hay transfer appeared to have important consequences on vegetation development because it speeded up the establishment of the target vegetation.

Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

An Ant-Plant Mesocosm Experiment Reveals Dispersal Patterns of Myrmecochorous Plants

For Central European herbs, ants are one common dispersal vector acting at relatively small spatial scales. Though extensively studied concerning the different benefits to plants, specific dispersal patterns mediated by ants have been reportedly very sparsely and without any validation. Thus, we studied the seed dispersal pattern of a set of myrmecochorous plant species in a novel mesocosm experiment. We examined the seed dispersal distances of four forest herbs (Hollow Root-Corydalis cava (L.) Schweigg. & Korte, Alpine Squill-Scilla bifolia L., and Common Dog-violet-Viola riviniana Rchb. and the annual Ivy-leaved Speedwell-Veronica hederifolia L.) by the red ant Myrmica ruginodis Nylander in 8.25 m2 large plots under natural conditions with and without ants. In the presence of Myrmica ants, the bulb geophytes C. cava and S. bifolia showed a significantly higher fraction of dispersed seedlings and a maximum dispersal distance of 322 cm. Estimated by nearest neighbor analyses, distances between single C. cava seedlings were significantly higher in ant plots than in exclosures without ants. The annual species Veronica hederifolia showed a few dispersed seedlings in ant plots only, while the diplochorous hemicryptophyte Viola riviniana germinated in a widely scattered manner with distances up to 241 cm due to ballochorous dispersal in both ant and exclosure plots, but with a maximum of 324 cm only by means of ants. Our results indicate the escape from the mother plant and dispersal for distance as an important benefit for myrmecochorous species, potentially accompanied by benefits through reduced competition

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

Creation of micro-topographic features: a new tool for introducing specialist species of calcareous grassland to restored sites?

Questions: What types of pre-sowing disturbance are most suitable to establish specialist forbs of calcareous grassland at previously agriculturally improved restored sites? What impact does management regime have on post-establishment abundance-dynamics? Location: Pegsdon Hills, Bedfordshire, UK. Methods: We set up a 4-yr experiment using a split-plot design to combine pre-sowing disturbance treatments at sub-plot level (undisturbed control, glyphosate spraying, harrowing, and creation of ridge-and-furrow features) with three post-establishment management regimes applied at main plot level in years 2–4, involving either summer cutting or summer cattle grazing, and presence or absence of spring sheep grazing, along with autumn cattle grazing in all regimes. After disturbance application, we sowed a seed mixture containing ten specialist species of calcareous grassland. Using quadrat-based methods, we monitored first-year establishment and subsequent dynamics, including reproductive status of species at quadrat level. Initial establishment and subsequent dynamics were analysed separately using LMM. Results: Initial establishment of sown species was promoted both by harrowing and by ridge-and-furrow creation. While some species were about equally promoted by both, several other species benefited more strongly or exclusively from ridge-and-furrow creation. Effects of disturbance largely persisted in subsequent years, but for some species, different dynamics were observed for harrowed and ridge-and-furrow treatments. Thymus pulegioides and Hippocrepis comosa gradually achieved higher abundances in the ridge-and-furrow treatment, in which notable levels of bare ground persisted for much longer than in the harrowed treatment. In contrast, Filipendula vulgaris and Pimpinella saxifraga achieved higher abundance in the harrowed treatment. Sown species tended to reach reproductive stage faster in the ridge-and-furrow treatment than in the harrowed treatment. By the end of the study, management regimes had resulted in few effects on species dynamics. Conclusions: Establishment of specialist species of calcareous grassland crucially depended on bare ground creation prior to sowing. Ridge-and-furrow creation resulted in more persistent reduction of competition than the standard practice of harrowing, provided more suitable conditions for low-statured specialist species, and generally enabled faster transition of introduced specialist species to reproductive stage. Our results thus illustrate potential benefits of using more severe disturbance when introducing specialist species of calcareous grassland at restored sites