Aim Species–area relationships (SARs) are fundamental scaling laws in ecology although their shape is still disputed. At larger areas, power laws best represent SARs. Yet, it remains unclear whether SARs follow other shapes at finer spatial grains in continuous vegetation. We asked which function describes SARs best at small grains and explored how sampling methodology or the environment influence SAR shape. Location Palaearctic grasslands and other non‐forested habitats. Taxa Vascular plants, bryophytes and lichens. Methods We used the GrassPlot database, containing standardized vegetation‐plot data from vascular plants, bryophytes and lichens spanning a wide range of grassland types throughout the Palaearctic and including 2,057 nested‐plot series with at least seven grain sizes ranging from 1 cm2 to 1,024 m2. Using nonlinear regression, we assessed the appropriateness of different SAR functions (power, power quadratic, power breakpoint, logarithmic, Michaelis–Menten). Based on AICc, we tested whether the ranking of functions differed among taxonomic groups, methodological settings, biomes or vegetation types. Results The power function was the most suitable function across the studied taxonomic groups. The superiority of this function increased from lichens to bryophytes to vascular plants to all three taxonomic groups together. The sampling method was highly influential as rooted presence sampling decreased the performance of the power function. By contrast, biome and vegetation type had practically no influence on the superiority of the power law. Main conclusions We conclude that SARs of sessile organisms at smaller spatial grains are best approximated by a power function. This coincides with several other comprehensive studies of SARs at different grain sizes and for different taxa, thus supporting the general appropriateness of the power function for modelling species diversity over a wide range of grain sizes. The poor performance of the Michaelis–Menten function demonstrates that richness within plant communities generally does not approach any saturation, thus calling into question the concept of minimal area.

Periodic monitoring of biodiversity changes at a landscape scale constitutes a key issue for conservation managers. Earth observation (EO) data offer a potential solution, through direct or indirect mapping of species or habitats. Most national and international programs rely on the use of land cover (LC) and/or land use (LU) classification systems. Yet, these are not as clearly relatable to biodiversity in comparison to habitat classifications, and provide less scope for monitoring. While a conversion from LC/LU classification to habitat classification can be of great utility, differences in definitions and criteria have so far limited the establishment of a unified approach for such translation between these two classification systems.Focusing on five Mediterranean NATURA 2000 sites, this paper considers the scope for three of the most commonly used global LC/LU taxonomies-CORINE Land Cover, the Food and Agricultural Organisation (FAO) land cover classification system (LCCS) and the International Geosphere-Biosphere Programme to be translated to habitat taxonomies. Through both quantitative and expert knowledge based qualitative analysis of selected taxonomies, FAO-LCCS turns out to be the best candidate to cope with the complexity of habitat description and provides a framework for EO and in situ data integration for habitat mapping, reducing uncertainties and class overlaps and bridging the gap between LC/LU and habitats domains for 123Landscape Ecol (2013) 28:905-930 DOI 10.1007 landscape monitoring-a major issue for conservation. This study also highlights the need to modify the FAO-LCCS hierarchical class description process to permit the addition of attributes based on class-specific expert knowledge to select multi-temporal (seasonal) EO data and improve classification. An application of LC/LU to habitat mapping is provided for a coastal Natura 2000 site with high classification accuracy as a result.

Aims Understanding fine‐grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine‐grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location Palaearctic biogeographic realm. Methods We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi‐natural) grasslands and natural grasslands are the richest vegetation type. The open‐access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions The GrassPlot Diversity Benchmarks provide high‐quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation‐plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology.

Questions Which environmental factors influence fine‐grain beta diversity of vegetation and do they vary among taxonomic groups? Location Palaearctic biogeographic realm. Methods We extracted 4,654 nested‐plot series with at least four different grain sizes between 0.0001 m² and 1,024 m² from the GrassPlot database, covering a wide range of different grassland and other open habitat types. We derived extensive environmental and structural information for these series. For each series and four taxonomic groups (vascular plants, bryophytes, lichens, all), we calculated the slope parameter (z‐value) of the power law species–area relationship (SAR), as a beta diversity measure. We tested whether z‐values differed among taxonomic groups and with respect to biogeographic gradients (latitude, elevation, macroclimate), ecological (site) characteristics (several stress–productivity, disturbance and heterogeneity measures, including land use) and alpha diversity (c‐value of the power law SAR). Results Mean z‐values were highest for lichens, intermediate for vascular plants and lowest for bryophytes. Bivariate regressions of z‐values against environmental variables had rather low predictive power (mean R² = 0.07 for vascular plants, less for other taxa). For vascular plants, the strongest predictors of z‐values were herb layer cover (negative), elevation (positive), rock and stone cover (positive) and the c‐value (U‐shaped). All tested metrics related to land use (fertilization, livestock grazing, mowing, burning, decrease in naturalness) led to a decrease in z‐values. Other predictors had little or no impact on z‐values. The patterns for bryophytes, lichens and all taxa combined were similar but weaker than those for vascular plants. Conclusions We conclude that productivity has negative and heterogeneity positive effects on z‐values, while the effect of disturbance varies depending on type and intensity. These patterns and the differences among taxonomic groups can be explained via the effects of these drivers on the mean occupancy of species, which is mathematically linked to beta diversity.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, and status changes for Italy or for Italian administrative regions of taxa in the genera Abies, Actinidia, Aloe, Amaryllis, Anredera, Arctotheca, Bidens, Cardiospermum, Celosia, Commelina, Cotoneaster, Cyclamen, Eclipta, Euphorbia, Grevillea, Hedera, Hibiscus, Impatiens, Juglans, Kalanchoe, Koelreuteria, Lindernia, Melinis, Myriophyllum, Nandina, Nicotiana, Oenothera, Oxalis, Parthenocissus, Phoenix, Phyllanthus, Physalis, Plumbago, Pteris, Quercus, Setaria, Symphytum, Tagetes, and Washingtonia. Nomenclatural and distribution updates, published elsewhere are provided as Suppl. material 1.

In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations and status changes to the Italian administrative regions for taxa in the generaAlchemilla,Arundo,Bupleurum,Clematis,Clinopodium,Cota,Crassula,Cytisus,Euphorbia,Hieracium,Isoëtes,Lamium,Leontodon,Linaria,Lychnis,Middendorfia,Ophrys,Philadelphus,Pinus,Sagina,Sedum,Taeniatherum,Tofieldia,Triticum,Veronica, andVicia. Nomenclature and distribution updates, published elsewhere, and corrigenda are provided as supplementary material.

The Scorzoneretalia villosae (= Scorzonero-Chrysopogonetalia) order was originally defined to describe the sub-Mediterranean grasslands of western Croatia, but its distribution range has since been extended to Albania, Bosnia and Herzegovina, Bulgaria, Italy, Kosovo, Montenegro, Slovenia and Serbia. Major syntaxonomic revisions of the order have been performed at the regional or national scale and show inconsistencies both for the syntaxonomic schemes and relative diagnostic taxa. This situation presents some difficulties in comparing or transferring findings between regions or when using syntaxonomic information for practical purposes. To tackle these inconsistencies, nearly nine hundred relevés already assigned to the Scorzoneretalia villosae were classified with the goal of establishing syntaxonomic relationships among associations. Diagnostic taxa of the main clusters of relevés were identified via Indicator Species Analysis (ISA). Results of statistical analyses were then interpreted from a syntaxonomic standpoint. Associations were ordinated (non-metric multidimensional scaling) on the basis of taxa frequencies in order to visualise their floristic and chorological relationships. Based on the results, associations were grouped within four alliances: Scorzonerion villosae, Chrysopogono-Saturejion subspicatae, Saturejion subspicatae and Centaureion dichroanthae were assigned to two new suborders, the meso-xerophytic Scorzonerenalia villosae and the xerophytic Koelerienalia splendentis, classified within the Scorzoneretalia villosae of the Festuco-Brometea. The order covers the western part of the Balkan Peninsula and, in the northern part of its range, the southeastern portion of the pre-Alpine sectors. Floristic similarities between the Scorzonerenalia villosae and other eastern meso-xerophytic syntaxa of the class have been highlighted. I review the nomenclature for the order, describing or validating two suborders and four associations for the first time, and lectotypifying three syntaxa.

This paper reports a survey on the weed flora and seed bank in an almond orchard sited in Apulia region (Southern Italy), where the following soil management practices have been compared for over 30 yrs: no-tillage, keeping the soil totally weed-free throughout the year by using pre-emergence herbicides to prevent plant emergence or post-emergence herbicides in case of weeds already emerged; no-tillage, with post-emergence herbicides; no-tillage, with mowing of natural weed flora in spring; cover cropping, with faba bean sown in November and green manured in springtime; conventional soil tillage. The different management techniques influenced significantly the weed flora in experimental plots, both in terms of quantity and quality. The seed bank was clearly impoverished after the long-term applications of pre-emergence herbicides, both in terms of richness and of diversity. During the fall period, the plots of conventional tillage or pre-emergence herbicides had less natural ground-flora than the others. During springtime, prior to the sward control practices, the plots treated by foliar herbicides or mowing had the highest total weed cover. We conclude that post-emergence weed control by mowing or using chemical herbicides or the green manure of the cover crop may be proposed to reduce impact to the soil and to promote the growth of abundant and sufficiently diversified and balanced flora. If appropriately managed, this flora can provide potential ecological services, without competing with the orchard, as suggested by the literature. During the autumn, natural flora can uptake soil nitrogen thus preventing leaching in the rainy season. In springtime, after the sward has been destroyed, natural flora can supply a substantial amount of biomass to the soil. Indicator species analysis was also used to find the species characterizing each treatment and some of their combinations. Weeds belonging to the Poaceae botanical family were significantly associated with post-emergence herbicides and mowing treatments. These species produce a substantial amount of biomass and have bunched roots; consequently, they supply beneficial effects by improving porosity and structure of the soil and reducing erosion hazard