122 research outputs found
Analysis of intraspecific seed diversity in Astragalus aquilanus (Fabaceae), an endemic species of Central Apennine
This work aims to study seeds of the endemic species Astragalus aquilanus from four
different populations of central Italy. We investigated seed morpho-colorimetric features
(shape and size) and chemical differences (through infrared spectroscopy)
among populations and between dark and light seeds.
• Seed morpho-colorimetric quantitative variables, describing shape, size and colour
traits, were measured using image analysis techniques. Fourier transform infrared
(FT-IR) spectroscopy was used to attempt seed chemical characterisation. The measured
data were analysed by step-wise linear discriminant analysis (LDA). Moreover,
we analysed the correlation between the four most important traits and six climatic
variables extracted from WorldClim 2.0.
• The LDA on seeds traits shows clear differentiation of the four populations, which can
be attributed to different chemical composition, as confirmed by Wilk’s lambda test
(P < 0.001). A strong correlation between morphometric traits and temperature (annual
mean temperature, mean temperature of the warmest and coolest quarter), colorimetric
traits and precipitation (annual precipitation, precipitation of wettest and
driest quarter) was observed.
• The characterisation of A. aquilanus seeds shows large intraspecific plasticity both in
morpho-colorimetric and chemical composition. These results confirm the strong
relationship between the type of seed produced and the climatic variables
Short-term functional response to post-fire vegetation dynamic: A case study in a Mediterranean Pinus halepensis forest
Wildfire events significantly affect plant communities. Understanding the post-fire vegetation dynamics and
how native and alien species interact to shape the composition and structure of the community is crucial to
address conservation policy. Dispersal mechanisms and resource exploration strategies are two functional
strategies which can explain variability in species response to disturbance. Here, we investigated how functional
traits shape the short-term dynamic after a wildfire event in a Mediterranean pine forest. We collected
plant co-occurrences and abundances in permanent plots of 100 m2 across four distinct sampling sessions
(from late winter to early autumn, every 2 months). Functionally relevant traits including leaf traits and
dispersal-related traits were also retrieved for the recorded species. We then derived the Grime’s strategies of
the recorded species from the collected leaf traits, and we computed the dispersal ability of each species as a
function of the corresponding dispersal traits. To compare Grime’s strategies and leaf traits across the
monitoring cycles, we calculated the community weighted mean for each cycle as the average of species trait
values in each plot. Further, we estimated variations in species abundances and species composition within
each plot by using temporal turnover analysis, which showed a continuous post-fire increase in communitylevel
vegetation cover and a strong compositional change driven by a spread of alien species. Associating
these patterns to the recorded functional traits revealed that dispersal ability is crucial in post-fire recolonization.
Moreover, ruderal species, being the most represented strategy soon after the fire, give way over time
to more competitive species showing higher leaf area. Thus, short-term vegetation recovery involves different
species-specific strategies that shape the ecological succession over time. Our case study highlights that
knowledge about how functional traits drive plant colonization strategies is critical to assess the post-fire
restoration status of Mediterranean pine forests
Grassland Changes in the Eastern Alps Over Four Decades: Unveiling Patterns Along an Elevation Gradient
Aims
Alpine valleys have faced escalating global changes in recent decades such as a decline of traditional management and rural expansion. Grasslands are likely the type of vegetation most affected by these transformations. This study investigates the multifaceted changes in plant diversity over the past four decades in a major valley of the Italian Eastern Alps and examines whether changes occurred uniformly across different elevations.
Location
Valsugana Valley, Eastern Alps, Italy.
Methods
In 2022, we resurveyed 115 vegetation plots (including vascular plants, mosses, and lichens) originally sampled in 1986–1988. Plots were collected in grasslands and span along an elevation gradient of 2000 m. At each time period, we automatically classified these plots using the EUNIS expert system of habitats. We analysed the variation over time in species richness, species diversity, beta diversity (turnover and nestedness), and relative proportion of life form, woodiness, and neophyte species along an elevation gradient, subdivided in low-, middle-, and high-elevation belts. Lastly, we quantified the number of gained, winning, stable, losing, and lost species.
Results
We found differences in the classification of EUNIS habitats and elevation-dependent changes in community diversity and composition. Many grassland types were transformed into other grassland types or into forests and man-made habitats. Species richness varied along the elevation gradient over time, being constant at lower elevations but markedly increasing at high elevations. Temporal turnover dominated across elevations, especially at lower sites, while nestedness components increased towards high elevations. Neophytes increased and hemicryptophytes decreased in the low-elevation belt, while therophytes and geophytes increased at low- and high-elevation belts. In the middle-elevation belt, many dry grassland species were replaced by nitrophilous and woody species. High-elevation witnessed species replacement with the loss of mountain species and the increase of therophyte and geophyte species.
Conclusions
Grasslands of Valsugana valley have undergone substantial changes over four decades. Different processes likely acted across the elevation gradient. Nonetheless the driver, impoverishment of semi-natural grassland species was observed over time across elevations. Understanding these changes in vegetation is essential for a comprehensive evaluation of ecological variations over time. Conservation management strategies should be tailored to address biodiversity changes at varying elevations to counteract the negative trends of plant diversity loss and the ongoing habitat transformation of grasslands in the Alps
A multitaxonomic assessment of Natura 2000 effectiveness across European biogeographic regions
AbstractThe Natura 2000 (N2K) protected area (PA) network is a crucial tool to limit biodiversity loss in Europe. Despite covering 18% of EU's land area, its effectiveness at conserving biodiversity across taxa and biogeographic regions remains uncertain. Testing this effectiveness is, however, difficult as it requires considering the non‐random location of PAs, and many possible confounding factors. Here, we used propensity score matching accounting for the confounding effects of biogeographic regions, terrain ruggedness, and land cover, when assessing the effectiveness of N2K PAs on the distribution of 1,769 priority species from EU's Birds and Habitats Directives, including mammals, birds, amphibians, reptiles, arthropods, fishes, molluscs, vascular and non‐vascular plants. We compared alpha, beta, and gamma diversity between matched selections of protected and non‐protected areas across EU's biogeographic regions using generalized linear models, generalized mixed models, and non‐parametric tests for paired samples, respectively, for each taxonomic group and for the entire set of species. While we found N2K PAs to host significantly more priority species than non‐protected land, this difference was not consistent across biogeographic regions and taxa. Total alpha diversity as well as alpha diversity of amphibians, arthropods, birds, mammals, and vascular plants were significantly higher inside PAs than outside, except in the Boreal region. Beta diversity was in general significantly higher inside N2K PAs than outside. Similarly, gamma diversity showed the highest values within N2K PAs, with some exceptions in Boreal and Atlantic regions. The planned expansion of the N2K network, as dictated by the European Biodiversity Strategy for 2030, should therefore target areas in the southern part of the Boreal region, areas with high species diversity of amphibians, arthropods, birds, mammals, and vascular plants, which are currently underrepresented in the N2K network.This article is protected by copyright. All rights reserve
Investigating elevational gradients of species richness in a Mediterranean plant hotspot using a published flora
The Apuan Alps are one of the most peculiar mountain chain in the Mediterranean, being very close to the coastline and reaching an elevation of almost 2000 m. Based on published flora, we investigated the distribution of plant species richness along the whole elevational gradient of this chain considering: (i) all species, (ii) endemic versus alien species; and (iii) functional groups of species based on Raunkiær life forms (RLF). Generalized Linear Models (GLMs) were used to analyse richness patterns along the elevational gradient, and elevational richness models versus the area of the elevational belts were fitted to test the effect of surface area. Our results showed decreasing species richness with increasing elevation. In contrast, endemic species richness increased along the elevational gradient. Alien species were mainly distributed at low elevations, but this result should be taken with caution since we used historical data. Species life forms were not equally distributed along the elevation gradient: chamaephytes and hemicryptophytes were the richest groups at high elevations, while therophytes showed highest species richness at low elevations. Our findings suggest that in the Apuan Alps there is a major elevational gradient in species composition that could reflect plant evolutionary history. Furthermore, we highlight the key role of published floras as a relevant source of biodiversity data.publishedVersio
Investigating sacred natural sites and protected areas for forest area changes in Italy
Forests will be critical to mitigate the effects of climate and global changes.
Therefore, knowledge on the drivers of forest area changes are important.
Although the drivers of deforestation are well known, drivers of afforestation
are almost unexplored. Moreover, protected areas (PAs) effectively decrease
deforestation, but other types of area-based conservation measures exist.
Among these, sacred natural sites (SNS) deliver positive conservation out-
comes while making up an extensive “shadow network” of conservation. How-
ever, little is known on the capacity of SNS to regulate land-use changes. Here,
we explored the role of SNS and PAs as drivers of forest loss and forest gain in
Italy between 1936 and 2018. We performed a descriptive analysis and
modeled forest gain and forest loss by means of spatial binomial generalized
linear models with residual autocovariates. The main drivers of forest area
changes were geographical position and elevation, nonetheless SNS and PAs
significantly decreased forest loss and increased forest gain. Although the neg-
ative relationship between SNS and forest loss is a desirable outcome, the posi-
tive relationship with forest gain is concerning because it could point to
abandonment of cultural landscapes with consequent loss of open habitats.
We suggest a legal recognition of SNS and an active ecological monitoring and
planning to help maintain their positive role in biodiversity conservation. As a
novel conservation planning approach, SNS can be used as stepping stones
between PAs increasing connectivity and also to conserve small habitat
patches threatened by human activities
Probabilistic and preferential sampling approaches offer integrated perspectives of Italian forest diversity
Aim: Assessing the performances of different sampling approaches for documenting community diversity may help to identify optimal sampling efforts and strategies, and to enhance conservation and monitoring planning. Here, we used two data sets based on probabilistic and preferential sampling schemes of Italian forest vegetation to analyze the multifaceted performances of the two approaches across three major forest types at a large scale.
Location: Italy.
Methods: We pooled 804 probabilistic and 16,259 preferential forest plots as samples of vascular plant diversity across the country. We balanced the two data sets in terms of sizes, plot size, geographical position, and vegetation types. For each of the two data sets, 1000 subsets of 201 random plots were compared by calculating the shared and exclusive indicator species, their overlap in the multivariate space, and the areas encompassed by spatially-constrained rarefaction curves. We then calculated an index of performance using the ratio between the additional and total information collected by each sampling approach. The performances were tested and evaluated across the three major forest types.
Results: The probabilistic approach performed better in estimating species richness and diversity of species assemblages, but did not detect other components of the regional diversity, such as azonal forests. The preferential approach outperformed the probabilistic approach in detecting forest-specialist species and plant diversity hotspots.
Conclusions: Using a novel workflow based on vegetation-plot exclusivities and commonalities, our study suggests probabilistic and preferential sampling approaches are to be used in combination for better conservation and monitor planning purposes to detect multiple aspects of plant community diversity. Our findings can assist the implementation of national conservation planning and large-scale monitoring of biodiversit
Integrals of life: Tracking ecosystem spatial heterogeneity from space through the area under the curve of the parametric Rao’s Q index
Spatio-ecological heterogeneity is strongly linked to many ecological processes and functions such as plant species diversity patterns and change, metapopulation dynamics, and gene flow. Remote sensing is particularly useful for measuring spatial heterogeneity of ecosystems over wide regions with repeated measurements in space and time. Besides, developing free and open source algorithms for ecological modelling from space is vital to allow to prove workflows of analysis reproducible. From this point of view, NASA developed programs like the Surface Biology and Geology (SBG) to support the development of algorithms for exploiting spaceborne remotely sensed data to provide a relatively fast but accurate estimate of ecological properties in vast areas over time. Most of the indices to measure heterogeneity from space are point descriptors : they catch only part of the whole heterogeneity spectrum. Under the SBG umbrella, in this paper we provide a new R function part of the rasterdiv R package which allows to calculate spatio-ecological heterogeneity and its variation over time by considering all its possible facets. The new function was tested on two different case studies, on multi- and hyperspectral images, proving to be an effective tool to measure heterogeneity and detect its changes over time
EU2030 biodiversity strategy: Unveiling gaps in the coverage of ecoregions and threatened species within the strictly protected areas of Italy
About 19 % of the Italian territory is covered by protected areas (PAs), 5.1 % of which fall in IUCN categories Ia and II, which can be considered strictly protected areas (StPAs). The 2030 EU Biodiversity Strategy sets a target of 30 % coverage for PAs (of which 10 % should be StPAs). We assessed the area coverage of StPAs, for the territory of Italy, with respect to biogeographical regions, ecoregions, elevation range, habitats, and the distribution of species threatened with extinction according to the IUCN Red List (Vulnerable, VU; Endangered, EN; or Critically Endangered, CR). We found that most of the StPAs are located in the Mediterranean biogeographical region, followed by the Alpine and Continental regions, and that the spatial distribution of such protected areas is biased towards higher elevation. Moreover, we found that three of the fourteen terrestrial ecoregions of Italy are not protected at all by StPAs (i.e., Illyrian, Ligurian-Provencal, and Central-Adriatic), while the Po Plain and the Sicilia Sections are only marginally protected. Moreover, nine habitats are not covered by any StPAs including one priority habitat (Inland salt meadows). Finally, we found unprotected species among freshwater fish (21), amphibians (3 VU, 3 CR), reptiles (1 CR), birds (2 NE), mammals (1 VU), and plants (20 VU, 14 EN, 21 CR). Our findings suggest that the current amount and spatial distribution of StPAs of Italy are far from the targets of the EU Biodiversity Strategy and needs improvements
A grid-based map for the biogeographical regions of Europe
© Pensoft Publishers. Background Biogeographical units are widely adopted in ecological research and nature conservation management, even though biogeographical regionalisation is still under scientific debate. The European Environment Agency provided an official map of the European Biogeographical Regions (EBRs), which contains the official boundaries used in the Habitats and Birds Directives. However, these boundaries bisect cells in the official EU 10 km x 10 km grid used for many purposes, including reporting species and habitat data, meaning that 6881 cells overlap two or more regions. Therefore, superimposing the EBRs vector map over the grid creates ambiguities in associating some cells with European Biogeographical Regions. New information To provide an operational tool to unambiguously define the boundaries of the eleven European Biogeographical Regions, we provide a specifically developed raster map of Grid-Based European Biogeographical Regions (GB-EBRs). In this new map, the borders of the EBRs are reshaped to coherently match the standard European 10 km x 10 km grid imposed for reporting tasks by Article 17 of the Habitats Directive and used for many other datasets. We assign each cell to the EBR with the largest area within the cell
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