Climate change is causing shifts in the distribution of many species and populations inhabiting mountain tops are particularly vulnerable to these threats because they are constrained in altitudinal shifts. Apennines are a relatively narrow and low mountain chain located in Southern Europe, which hosts many isolated populations of mountain species. The butterfly Erebia pandrose was recorded for the last time in the Apennines in 1977, on the top of a single massif (Monti della Laga). We confirmed the presence of a small, isolated population of E. pandrose in the Apennines, at a distance of more than 400 km to any other known populations. Then, we examined the cytochrome c oxidase subunit 1 mitochondrial DNA marker of this species across the Palaearctic area and estimated the potential decline over the Alps and the Apennines due to future climatic changes. The Apennine population represents an endemic lineage characterised by eight mutations over the 658 bp analysed (1.2%). In the Alps and Apennines, this species has shifted uphill more than 3 m per year since the end of the 19th century and more than 22 m per year since 1995. Species distribution models suggested that these mountain populations will experience a generalised loss of climatic suitability, which, according to our projections, could lead to the extinction of the Apennine population in a few decades. Erebia pandrose has the potential to become a flagship species for advertising the risk of losing unique fractions of genetic diversity for mountain species.
SUMMARYBecause of their isolation, biotic communities of urban green spaces are expected to be similar to those of oceanic islands. This should be particularly true for insects, which represent an important component of urban faunas. The equilibrium theory of island biogeography (ETIB) allows for the formulation of some hypotheses regarding the influence of the geographical characteristics of green spaces on insect species richness and extinction risk. Based on island biogeography principles, we present eight predictions on how green space characteristics should influence insect species richness and loss. We analysed the current literature in order to determine which predictions were supported and which were not. We found that many studies gave outcomes that support ETIB predictions about the effects of area and isolation of green spaces; we found no strong support for predictions about shape and extent of native habitat in the literature that we reviewed. Most of the available studies dealt with patterns in species richness, whereas insect species loss has been rarely investigated. Future developments in the application of island biogeography principles to urban insect conservation should address temporal trends in species persistence and the analysis of species co-occurrence and nestedness.
The concept of generic diversity expresses the ‘diversification’ of species into genera in a community. Since niche overlap is assumed to be higher in congeneric species, competition should increase generic diversity. On the other hand, generic diversity might be lower in highly selective environments, where only species with similar adaptations can survive. We used the distribution of tenebrionid beetles in Central Italy to investigate how generic diversity varies with elevation from sea level to 2400 m altitude. Generic diversity of geophilous tenebrionids decreased sharply with elevation, whereas the generic diversity of xylophilous tenebrionids showed similarly high values across the gradient. These results suggest that geophilous species are more sensitive to variation in environmental factors, and that the advantages of close relationships (similar adaptations to harsh conditions) are greater than the possible drawbacks (competition). This is consistent with the fact that geophilous tenebrionids are mostly generalist detritivores, and hence weakly affected by competition for resources. By contrast, xylophilous species are more protected from harsh/selective conditions, but more limited by competition for microhabitats and food. Our results support the environmental filtering hypothesis for the species composition of tenebrionid beetles along an elevational gradient.
Despite the increasing interest in elevational patterns in biodiversity, few studies have investigated variations in life forms and biogeographical composition, especially in the Mediterranean biome. We investigated elevational patterns in species richness, biogeographical composition (chorotypes) and life forms (Raunkiaer classification) along an elevational gradient in a Mediterranean mountain (Central Italy). We found a general hump-shaped pattern of species richness, which can be explained by harsher conditions at the lowest and highest elevations. This pattern is distinctly related to prevalence at mid elevations of species with European and Euro-Asiatic distribution, which are favored by a temperate climate. Phanerophytes and geophytes (which are mainly associated with woods) were concentrated at mid elevations where woodlands prevail. Hemicryptophytes increased with elevation, consistently with their ability to cope with high altitude climatic conditions. Mediterranean species declined with elevation because they are negatively affected by decreasing temperatures. Chamaephytes showed a U-shaped pattern, suggesting they are able to cope with arid and cold conditions at the extremes of the gradient. Endemics increased with elevation because of their association with mountainous areas as key places for endemism evolution. These results illustrate how elevational patterns in species richness, biogeographical composition and life forms are interrelated and demonstrate reciprocal insights for understanding current vegetation settings.
The species-area relationship (SAR) is one of the most investigated patterns in ecology and conservation biology, yet there is no study testing how different levels of urbanization influence its shape. Here we tested the impact of urbanization on avian SARs along a rural-urban gradient using the breeding birds of Rome (Central Italy). We divided the city into 360 cells of 1 km2. Each cell was classified as rural, suburban or urban using the proportion of impervious surface calculated from remote sensing data. For each of these three landscape categories, we constructed a SAR as a species accumulation curve (Gleason function) using bird species distribution data. SAR intercepts (i.e. the number of species per unit area) decreased from rural to urban areas, which indicates that urbanization depressed the number of species, reflecting the loss of specialized species strictly associated with natural habitats. The slope was highest for the rural curve, indicating that natural landscapes have the highest turnover due to their higher habitat heterogeneity. A higher slope for the urban cells, compared to the suburban ones, can be explained by the presence of green spaces embedded in the built-up matrix which host different avian communities. Previous studies that compared whole cities with natural areas failed to find differences in the respective SARs. Our study, which constructed SARs for different levels of urbanization, indicated significant changes in the SARs along the rural-urban gradient. Further analyses in other cities and taxa will be useful to test how general are our findings.
Since management practices profoundly influence soil characteristics, the adoption of sustainable agro-ecological practices is essential for soil health conservation. We compared soil health in organic and conventional fields in the Abruzzi region (central Italy) by using (1) the soil biology quality (QBS) index (which expresses the level of specialisation in soil environment shown by microarthropods) and (2) microarthropod diversity expressed by Hill numbers. QBS values were calculated using both the original formulation based on only presence/absence data and a new abundance-based version. We found that organic management improves soil biology quality, which encourages the use of organic farming to maintain soil health. Including arthropod abundance in QBS calculation does not change the main outcomes, which supports the use of its original, speedier formulation. We also found that agricultural fields included in protected areas had greater soil health, which shows the importance of the matrix in determining agricultural soil health and highlights the importance of land protection in preserving biodiversity even in managed soils. Finally, we found that soil biology quality and microarthropod community structure are distinctly influenced by certain physical and chemical characteristics of the soil, which supports the use of microarthropods as biological indicators.
1. Levels of endemism are usually expressed as percentage of endemics among all species recorded in a given area. Endemism levels also vary among taxa, yet inter-taxon variation in endemism levels has received much less attention.2. We used the Italian tenebrionids to investigate how endemism levels vary among different but related lineages. We evaluated endemism variations among taxonomic levels both as a percentage of endemics to the number of species included in a given taxon (i.e. the tendency of a taxon to produce endemics) and as a percentage to the total number of species (i.e. the importance of that taxon to the overall endemic component). We also considered the residuals of regression lines of endemics against non-endemics. We tested the influence of phylogenetic position, lifestyle, and body size on the percentage of endemics within genera.3. Use of percentages and residuals gave similar outcomes. Pimeliinae were the subfamily with the highest level of endemism. Erodiini, Pimeliini, Tentyriini, Asidini, Opatrini, and Pedinini were among the tribes with the highest endemism levels. Asida, Pimelia, Tentyria, and Opatrum were the genera with the highest levels of endemism.4. Phylogenetic position and body size affected significantly endemism levels, with genera including larger species being also those with higher endemism, whereas lifestyle was not significant. This suggests that endemism in the Italian tenebrionid beetles is phylogenetically constrained and that lines including larger species (which are possibly less subject to passive dispersal) tend to be richer in endemics, independently from their lifestyle.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.