Root seasonal pattern, spatial distribution, and C:N ratio of matgrasspasture (Nardus stricta L.) in the Lombardy Prealps

The aim of the present study was to investigate carbon and nutrient cycling and the role of root dynamics in terrestrial ecosystems such as large abandoned pastures and natural grasslands present in the Prealps, for which below-ground processes are currently enigmatic. In particular, we quantified root/leaf biomass and C:N ratio throughout two growing seasons. Additionally, root traits such as root length density (RLD), root mass density (RMD), and root diameter classes (RDC) were also investigated with the aim of understanding the spatial distribution of roots in the soil. In our samples, we found that the roots could be divided into three main diameter classes and hence quantified the presence of each class along the soil profile. With regard to total root biomass, we found the occurrence of two peaks of biomass accumulation during the growth season, and when biomass accumulation was compared with climatic data, it was impossible to obtain a clear indication of the root turnover rate. In fact, the strong influence of grazing on the above-ground biomass could have affected, in turn, root biomass. In future, this possible complication will be avoided by repeating the measurements within enclosures to avoid grazing interference. We found that C:N ratio remained constant, with a single peak, suggesting a lower root decomposition during the warmest period (August 2006). The concentration of nitrogen in roots decreased with depth as a result of a decrease in roots with smaller diameters. The reverse was found for carbon content, which increased with depth, probably due to an increase in roots with larger diameters. This study represents the first attempt to estimate root turnover rates in this prealpine ecosystem, which have been analysed to date only for the above-ground biomass

Characterization of native hayseed: guaranteeing a seed mixture for habitat and species conservation

Here we present data on hayseed quality (purity, seed content and germination rate of seeds) for lots collected from different vegetation types and with different brush harvester types. We show that it is possible to provide labelling information with regard to hayseed quality, to calculate sowing denisties and help consumers understand the quality and performance of the product they have bought

Characterisation of brush-harvested hayseed quality (purity, seed content and germination) for the calculation of optimal sowing densities

Several projects demonstrate the utility of hayseed for ecological restoration, but how hayseed should be employed remains ambiguous as no standard procedure currently exists for hayseed characterisation. In Europe an absence of guidelines partly reflects the lack of a requirement by EC Directive 2010/60/EU for specific data quality parameters for directly harvested seed mixtures. However, the Directive states that directly harvested seed mixtures should be appropriate for restoration of each given habitat, and a density of 8000 established seedlings m-2 has been shown as a requirement for successful revegetation in alpine grasslands (Florineth 2007). We developed a method for the standardised characterisation of hayseed lots to allow labelling of recommended sowing densities for hayseed from different grassland types, inspired by the quality tests usually applied to commercial seed (such as those of the International Seed Testing Association; ISTA 2017). Hayseed was collected from 49 grassland donor sites in Lombardy, northern Italy, using three different types of brush harvester, and characterised in terms of purity (seed:inert plant material), seed content (number of seeds per unit hayseed weight) and germination capacity (density of seedlings emerging over a given area). Hayseed was also used for restoration and restored areas monitored in terms of seedling density and cover. The mean yield across all donor sites was 60.6 kg ha-1 (min./max. 19.6 to 131.8 kg ha-1). Seed content exhibited a mean of 536.5 seeds g-l, ranging from 82.4 to 2635.0 seeds g-l, and differed between brush harvester types. The mean purity across sites was 28% seed, ranging from 5 to 68%, and was also affected by brush harvester type (p<0.05). Mean germinability was 7000 seedlings m-2 (at 30d from sowing). Recent tests conducted on sub-lots of hayseed preserved for several years (3, 4 or 5), demonstrate a significant increase in germination during short term storage (germination differences in the first and fifth years for three hayseed lots): similar effects have been noted for single species of Poaceae (e.g. Shaidaee et al. 1969). During revegetation trials, complete soil cover was generally achieved after three months, associated with declining seedling density due to shifts in competitive dominance. Monitoring of sites over several years shows the progressive and spontaneous ingress of other species from surrounding vegetation, leading to floristic enrichment and development of the grassland. Optimal sowing density for each hayseed lot ranged between 5 and 94 g of hayseed per m2: values for most lots were below the sowing densities for commercial seed mixtures advised by ERSAF (2001) for establishment of vegetation for erosion control (30 to 50 g m2). Standardised characterisation of hayseed lot quality is possible in a way that allows sowing density recommendations and labelling to be carried out for each type of donor grassland

The functional approach in the analysis of herbaceous communities: an example from highly biodiverse Prealpine grasslands.

The functional approach for community description and analysis is now widespread among plant ecologists. Functional analysis has a key role at different levels, as shifts in functional traits that currently result from changes in climate, soil and/or management, have predictable effects in rates and magnitudes of ecosystem processes. Moreover, plant functional types represent a useful means to deal with communities characterised by high species diversity, and could be fundamental in conservation ecology and community management. A functional investigation was performed on calcareous grasslands from Monte Barro, a small mountain in Lombard Prealpine District. Plant attributes for several vegetative traits were gathered on 151 species from field and laboratory measurements. Ordination (PCA) and fuzzy clustering then led to species allocation to plant strategies according to Grime\u2019s C-S-R triangular scheme (GRIME, 2001). According to the results of multivariate analysis, two main axes of variation act among species from Prealpine calcareous grasslands, the first one referring to competitive ability and the second one to effective resource use. As to the functional characterisation of the examined communities, species mainly belong to stress-tolerant strategy, while ruderality is almost not represented. A clear pattern of variation in strategy distribution among vegetation types was recorded by plotting different grasslands along possible light/soil moisture gradients: increase in nutrient and water availability is related to a reduction in the stress-tolerant species while competitors increase, with a consistent progressive decrease in species number.Moreover, a strong association between functional types and species richness was recorded, as the communities with the highest species number were also characterised by the most even distribution of different strategies

The survival strategy of the alpine endemic Primula glaucescens is fundamentally unchanged throughout its climate envelope despite superficial phenotypic variability.

The survival of alpine species in changing climates depends on dispersal or adaptation. However, it is unclear whether trait variability along elevation/climatic gradients is adaptive or represents stress towards lower/warmer elevations, particularly for the endangered endemics for which protected status and plant longevity preclude experimental study. We chose one such species, known for its phenotypic variability (Primula glaucescens, endemic to the southern Alps), and quantified key functional traits in situ throughout its range, correlating these with elevation as a proxy for climate. Larger leaves were evident towards lower elevations, but tissue nitrogen dilution and limited regenerative fitness were symptomatic of stress. Specific leaf area, a correlate of relative growth rate, was consistently low: the entire species exhibits conservative leaf economy and inherently slow growth. This seemingly variable species exhibits superficial variability around a fundamentally conservative, cold-adapted survival strategy, and thus phenotypic variability is unlikely to facilitate the persistence of alpine endemics during rapid climate warming

Are morpho-functional traits reliable indicators of inherent relative growth rate for prealpine calcareous grassland species?

Relative growth rate (RGR) is a fundamental trait for comparative plant ecology but cannot be measured in situ, leading to problems in interpreting vegetation function. However, the components of RGR (net assimilation rate (NAR), leaf area ratio (LAR), leaf weight ratio (LWR), and specific leaf area (SLA)) can be calculated for wild plants from morphological measurements (leaf area, leaf dry mass, whole plant dry mass), which potentially reflect RGR. Seeds of 19 species from Italian prealpine calcareous grasslands were collected and seedlings were cultivated under controlled conditions. RGR, NAR, LAR, LWR and SLA were analysed. The results demonstrated that RGR was positively correlated with SLA and LAR (p<0.01). Furthermore, LAR was positively correlated with LWR and negatively with NAR (p<0.05). Monocotyledons showed significantly higher LAR, LWR and NAR than dicotyledons, as the latter allocated a greater proportion of biomass to stems, but RGR and SLA showed no such phylogenetic constraint. Therefore SLA is the most reliable indicator of RGR in ecological and functional surveys of prealpine calcareous grasslands, and has the additional advantage that it can be measured from leaf material alone. Lower mean RGR and SLA for calcareous grassland species suggests that this vegetation is less likely to recover from the effects of disturbance than meadows and dry meadows

Il Centro Regionale per la Flora Autoctona della Lombardia.

Lombardy is characterised by a remarkable variety of plant communities and landscapes that often show a high species richness with the presence of several endemic and rare species. However the region is one of the first areas for density of population, development rate and productive activities in Italy and Europe as well: very particular ecosystems (limestone prairies, lowland heathlands, peat bogs, etc.) often intermingle with towns, factories, quarries and so on. Beyond the traditional enterprises for the conservation of biological diversity based on the creation of protected areas, the regional administration has recently founded the \u201cCentro per la Flora Autoctona\u201d (Wild Plants Centre), whose main aim is the acquisition of knowledge and techniques to warrant the availability of wild shrubs and herbs suited to 1) environmental restoration, and 2) rare and/or endangered species conservation project