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Questions To what extent have semi-natural grassland plant species composition and functional traits changed during the past five decades? Which are the main directions of change? Which environmental, management and landscape factors have determined these changes? Location Central and southern Apennines of Italy. Methods In 2013-2014, we used a stratified random sampling design to revisit 132 semi-natural grasslands originally sampled between 1966 and 1992. The exact locations of the historical plots were not available but they were associated with detailed vegetation maps. Plots were divided in 17 groups based on study area and original community type. To assess changes in species composition we ran PERMANOVA and RDA. The extent of change was estimated by comparing each new plot with the quantitative species pool of the corresponding historical group; species composition changes were calculated using Bray-Curtis coefficient, and shifts in functional traits were quantified as differences in community-weighted means. These measures of change were used as response variables in mixed effects models including climate, topography, management and landscape metrics as explanatory variables. Results The largest changes were related to successional dynamics, which occurred mainly in grasslands developing at low altitude and in the flattest sites where the soil organic horizon was relatively thick. Colonization by shrubs and trees was facilitated by high soil pH and amount of adjacent forests. Also, management factors affected the patterns of shifts in species composition and functional traits: grazing intensity was negatively related to the degree of compositional change as well as to the abundance of woody species, whereas the increase of species associated with frequent grazing disturbance was found at sites with higher values of soil salinity. Conclusions Apennine semi-natural grasslands have undergone substantial changes in species composition and functional traits during recent decades. Compositional changes mainly indicated successional dynamics, likely following a decrease in grazing intensity, whereas some more accessible grasslands experienced an increase in disturbance-tolerant species. The combination of the re-visitation approach with functional traits allowed us to clarify different directions of changes in species composition, adding information on the ecological processes related to these changes. [ABSTRACT FROM AUTHOR]

The extension of forest area is a globally accepted tool to offset CO 2 emissions from deforestation and the combustion of fossil fuels. The common assumption is that in addition to the perceived climate benefits increasing forest area will also support biodiversity, thus making afforestation a “win-win scenario”. Based on the existing scientific evidences, we show that joined climate and biodiversity benefits are strongly context-dependent and that the outcome of afforestation is often highly questionable. In Europe, grasslands managed at low intensity contribute substantially to biodiversity conservation and carbon storage. However, many of these grasslands have been lost due to abandonment and subsequent spontaneous succession towards woody vegetation, or due to land use intensification. Moreover, grasslands are the ecosystems most often deliberately afforested in the context of EU carbon-centered policies that may thus counteract biodiversity conservation programmes. By reviewing the main EU policies targeting forests and grasslands, we found a striking ambivalence between policies and funding schemes addressing grassland conservation on the one hand (e.g. Habitats Directive, green payments within the Common Agricultural Policy) and those supporting afforestation on the other (e.g. rural development funds). We suggest three measures towards a better harmonization of the European Union policies that target forest and grassland ecosystems: (1) promoting the alignment of the decisions taken across different policy sectors; (2) focusing on the whole range of ecosystem services and biodiversity issues rather than on carbon management only; (3) valuing systems managed at low-intensity for their multifunctionality. [ABSTRACT FROM AUTHOR]

Questions What are the main drivers of variation in beta-diversity for Bromus erectus semi-natural dry grasslands of habitat 6210(*) at different scales? How should environmental variables and spatial patterns be taken into account to conserve the maximum possible beta-diversity within the habitat? Location Central Italy. Methods We used 195 vegetation relevés distributed in three nested extents: a single mountain, a mountain chain and southern Lazio. Multiple regression on distance matrices was performed using dissimilarity matrices based on: (1) species abundances as response variables; (2) spatial coordinates and environmental parameters (altitude, slope, percentage of rock and stone coverage, aspect, annual rainfall) as explanatory variables. The two groups of explanatory variables were used separately to partition the variation, and jointly to assess the relative contribution of each individual variable. Those variables found to significantly affect beta-diversity were used to: (1) compare beta-diversity levels between a set of randomly selected and a set of stratified relevés; and (2) analyse the habitat distribution across environmental gradients. These analyses, together with the curves describing the relationships between spatial distances and composition dissimilarities, were used to inform management decisions for the habitat. Results Most of the variance was explained by environmental variables, whose share was higher in the smallest and intermediate extent than in the broadest extent. Community dissimilarity increased in proportion to differences in altitude and spatial distances at every extent. Accordingly, at all the extents, the selection of relevés stratified by altitude or selected taking into account a minimum spatial distance included significantly higher levels of within-habitat beta-diversity, than randomly selected relevés. The relation of beta-diversity to the variation in aspect and annual rainfall varied at different extents. Conclusions Our results demonstrate that dry grassland management plans aimed at conserving the maximum within-habitat beta-diversity should take into account variation in environmental variables, among which altitude proved to be a critical factor at every extent. Also, spatial distances positively affect within-habitat beta-diversity levels, and scale-dependent minimum distances among habitat patches should be taken into account when selecting patches of habitat 6210(*) to be conserved in the study area. [ABSTRACT FROM AUTHOR]

In Europe, the conservation of extensively grazed semi-natural grasslands is addressed by agricultural policies whose effectiveness is questioned. We studied sub-xerophilous Bromus erectus semi-natural grasslands to analyse the interactions among: i) agri-environmental payments, ii) grazing regimes, iii) environmental conditions, iv) habitat conservation state, and v) forage yield and quality. We sampled 98 plots across 19 farms and unmanaged control areas in five regions encompassing Italy and Switzerland. We fitted two piecewise structural equation models (SEM) to infer direct and indirect effects of agri-environmental payments, grazing regimes and environmental conditions on proxies of habitat conservation state, (i.e., the number and cover of diagnostic species), and forage yield and quality (i.e., specific leaf area - SLA, leaf dry-matter content - LDMC, sward height and pastoral value). Agri-environmental payments contributed to maintain grazing management and in turn to preserve the habitat biodiversity and functions. Payments did not affect stocking rates, but determined a more even distribution of grazing intensity, with positive effects on habitat conservation state and negative outcomes for LDMC. Conversely, LDMC increased with stocking rates. Among environmental condition, elevation and soil carbonates content had a positive effect on the habitat conservation state, while slope exerted only indirect effects on forage quality and diagnostic species by reducing fine-scale grazing intensity. Overall, the effectiveness of payments largely depended on the scale of measures' implementation. Farm-level grazing contracts and periodic field monitoring would allow to influence the fine-scale grazing intensity and to implement a result-oriented approach towards the objectives of the post-2020 CAP. • Payments do not influence stocking rates, but fine-scale grazing intensity. • Fine-scale grazing intensity affects habitat conservation and forage provision. • Stocking rates affect forage yield and quality, but not habitat conservation state. • Elevation, soil carbonates and slope influence habitat conservation state. • Payments should include farm specific grazing contracts and habitat monitoring. [ABSTRACT FROM AUTHOR]