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Prague, Czech Republic

Pitzalis M.,Third University of Rome | Amore V.,Third University of Rome | Montalto F.,Third University of Rome | Luiselli L.,Institute of Environmental Studies | And 3 more authors.
Tropical Zoology | Year: 2016

A considerable part of community ecology literature questioned what are the main drivers of ecological relationships in an organismal community. We analysed this focal question by studying blister beetle (Meloidae) assemblages in Southern Africa. We explored the ecological distribution of 48 species across underlying bioclimatic (e.g. temperatures and precipitation regimes), environmental factors (biomes, vegetation structure) and the taxonomic heterogeneity of each groups inhabiting major biomes of Namibia across their main biological and ecological traits, by Canonical Correspondence in order to get an ordination plot. Monte Carlo methods were used to test for randomness of the data ordination. Ordination plot identified three main assemblages, one being constituted by strictly semiarid savannah species (camelthorn, mountain, karstweld, thornbush, mixed tree and shrub, dwarf shrub, mopane and forest savannahs), one much larger and less homogenous second assemblage, inclusive of more generalist species from Karoo and semi-desert habitats, living also in arid savannahs, and the third one including Nama Karoo species. All the three assemblages were taxonomically very heterogeneous, showing that phylogenetic relationships are probably less relevant than interspecific ecological relationships among species of the same group to determine present-day community structure in these animals. © 2016 Istituto per lo Studio degli Ecosistemi of the Consiglio Nazionale delle Ricerche, Firenze Source

Pitzalis M.,Third University of Rome | Bologna M.A.,Third University of Rome | Luiselli L.,Institute of Environmental Studies | Luiselli L.,ENI S.p.A
Acta Oecologica | Year: 2013

We studied evenness and species richness in two assemblages of soil arthropods at six contiguous study plots in Mediterranean ecosystems of central Italy, three of these plots being burnt and three unburnt. We analysed these aspects of community structure by diversity-dominance diagrams comparisons made through analysis of covariance on respective slopes and ordinate intercepts. We observed consistent patterns in both Collembola and Oniscidea assemblages, either in burnt and unburnt plots. Evenness did not change among study plots and across habitats, either before or after fire, whereas species' composition was significantly altered by fire. Results from our study implied that evenness and species diversity are clearly affected in a different and independent way by fire. Hence, it is not acceptable to focus on only the evenness when looking at the effects of controlled fires for environmental management reasons. © 2013 Elsevier Masson SAS. Source

Pitzalis M.,Third University of Rome | Amore V.,Third University of Rome | Montalto F.,Third University of Rome | Luiselli L.,Institute of Environmental Studies | And 2 more authors.
European Journal of Entomology | Year: 2014

Ecologists have identified several correlates of biological rarity in animals. Among the various correlates identified so far, three are explored in this paper: (a) abundance is correlated with absolute body size in animals; (b) phylogenetically primitive taxa are overrepresented in samples of rare species; (c) more specialized species are rarer than less specialized species. Here we use Namibian blister beetles (Coleoptera: Meloidae) as a model system for exploring these issues. We used data from five field expeditions, which resulted in the identification of 891 beetles belonging to 76 species collected from 191 sites. 13% of the species accounted for over 50% of the individuals; 22% of all species were represented by singletons. Abundance patterns differed significantly among the different trophic categories, with non-pollinophagous (non-specialized) species being more abundant than weed-eaters and pollinophagous (specialized) species. Species of phylogenetically basal tribes were less abundant than those of more derived groups. Trophic category and phylogenesis did not have a synergic effect in determining the relative abundance of the species, and body size had no influence on their abundance. Source

Zapponi L.,Third University of Rome | Luiselli L.,Institute of Environmental Studies | Luiselli L.,University of Camerino | Cento M.,Rivers State University of Science And Technology | And 2 more authors.
Basic and Applied Ecology | Year: 2014

The role of the matrix for the functionality of residual patches and therefore for species persistence has been recently recognised. However its influence on assemblage structure and composition is still unclear. We studied the effect of both patch and matrix attributes on community assemblage structure and composition in a fragmented landscape of central Italy. We used bird assemblages as a study model. Birds were sampled in 24 wood patches and distribution patterns were analysed considering both assemblage and guild-level responses. Patch composition and structure together with landscape patterns quantified with GIS were used as explanatory variables. The assemblages appeared to be strongly influenced by the landscape context, both in terms of composition and configuration. The functional connectivity of the patches, in terms of amount of neighbouring borders between woods and hedgerows, the shape of the woods in the matrix, together with the age of the patches, expressed as tree diameter, acted as the essential determinants, and even if the assemblages presented a significant nested structure, seven out of 40 species showed an idiosyncratic distribution. The study of the association between functional guilds and environmental parameters highlighted the influence of ecological constraints on the occurrence of unexpected presences and absences, suggesting the ability of some species to perceive and exploit matrix habitats. The matrix holds the capability to at least mitigate the effects of isolation and habitat loss, and the semi-natural elements of the mosaic may represent a biodiversity reservoir in an otherwise deprived landscape. © 2014 Gesellschaft für Ökologie. Source

Hawken S.,University of New South Wales | Metternicht G.,Institute of Environmental Studies | Chang C.W.,National University of Singapore | Liew S.C.,National University of Singapore | Gupta A.,University of Wollongong
35th Asian Conference on Remote Sensing 2014, ACRS 2014: Sensing for Reintegration of Societies | Year: 2014

The semi-aquatic, aquatic and green spaces of emerging Southeast Asian mega-cities act as ecological infrastructure, providing diverse ecosystem services to rapidly, growing, urban populations. The cultural and natural biodiversity integrated within urban ecological infrastructure is a key to metropolitan sustainability. However, rapid urban development has left stream systems, urban agriculture, wetlands and urban forests as fragmented spaces vulnerable to future development. This paper addresses such issues by reviewing methods for mapping and monitoring urban ecological systems through multi-sensor earth observation for urban planning. The potential of various satellite sensors is discussed in relation to their ability to reveal different aspects of ecological infrastructure. We conclude that the synergistic combination of data from multiple sensors can provide more reliable and accurate information especially when classifying complex systems such as ecological infrastructure. The potential advantages of integrating information from multiple sensors include improved timeliness, complementarity, cost-effectiveness and better certainty when compared to information from single sensors. Classifications need to recognize the complexity of the urban-rural continuum and highly heterogeneous desakota environments. This issue is explored with reference to Ho Chi Minh City, Vietnam. Source

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