SPACEnvironment

Rome, Italy

SPACEnvironment

Rome, Italy

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Bombi P.,SPACEnvironment | Capula M.,Museo Civico di Zoologia | D'Amen M.,SPACEnvironment
Animal Biology | Year: 2011

Sardinian populations of the snake Hemorrhois (= Coluber) hippocrepis are likely the most endangered populations of snakes in Italy. Major threats to survivorship are the anthropogenic habitat alteration and the extremely low population density, while nothing is known about the potential effects that climate change could exert on this species. The main goal of this paper is to provide helpful instruments for the short-and long-term conservation of H. hippocrepis in Sardinia. By means of an ecological modeling approach, we derived the Sardinian whip snake habitat suitability map, and we compared the potential range extent under present condition and future climatic scenarios. Results clearly show an alarming trend for H. hippocrepis conservation: changing climate conditions will cause a dramatic reduction on suitable surface since 2020, with a further collapse by 2050 (down to 11 km 2). We also identified areas of species potential persistence up till 2050, where prospective management initiatives could have the greatest probability of success in this region. In particular, only one existing protected area will likely still keep suitable habitats for H. hippocrepis. Therefore, we suggest that very careful management of this relictual area should be implemented by now if we really want to save these exceedingly threatened snake populations. © 2011 Koninklijke Brill NV, Leiden.


Bombi P.,SPACEnvironment | Vignoli L.,Third University of Rome
African Journal of Herpetology | Year: 2011

The southern rock lizard Australolacerta australis is a rock-dwelling lizard endemic to South Africa. The phylogenetic relationships of this species with other lacertid lizards are still not clear and have never been assessed in any phylogeny of Lacertidae using DNA sequence data. In this study we employed 3 044 base pairs from mitochondrial cytochrome b, 12S and 16S rRNA genes to investigate the phylogenetic position and the evolutionary history of A. australis. We performed phylogenetic analyses under the assumptions of Maximum Likelihood and Bayesian inference and estimated the timing of the cladogenic events related to A. australis by using a relaxed molecular clock method. Our phylogenetic reconstruction clearly placed A. australis within the southern African branch of the tribe Eremiadini including genera Tropidosaura, Meroles, and Pedioplanis. The former genus constitutes with A. australis a clade endemic to southernmost mountains of Africa. The radiation of this southern African clade is estimated to have occurred during the Mid Miocene (14.7-11.5 Mya), and it was likely due to the climate changes that occurred in the South African region at that time. © 2011 Herpetological Association of Africa.


Bombi P.,SPACEnvironment | D'Amen M.,SPACEnvironment
Diversity and Distributions | Year: 2011

Aim Defining priority areas for conservation is essential to minimize biodiversity loss, but the adoption of different methods for describing species distributions influences the outcomes. In order to provide a robust basis for the conservation of freshwater turtles in Africa, we compared the effect that different species-mapping approaches had on derived patterns of species richness, species vulnerability and protected-area representativeness. Location Africa. Methods We adopted three different approaches with increasing complexity for generating species distribution maps. The first approach was based on the geographic intersection of species records and grid squares; the second on the union of local convex polygons; and the third on inductive distribution modelling techniques. We used distribution maps, generated using these three approaches, to determine conservation priorities based on geographic patterns of species richness and vulnerability, as well as for conducting gap and irreplaceability analyses. Results We obtained markedly different distribution maps using the three methods, which in turn caused differences in conservation priorities. The grid-square approach underestimated range sizes and species richness, while the polygon approach overestimated these attributes. The distribution modelling approach provided the most realistic outcome in terms of diversity patterns, by minimizing both commission and omission errors. An integrated map of conservation priority - derived by combining individual measures of priority based on the distribution modelling approach - identified the Gulf of Guinea coast and the Albertine Rift as major priority areas. Main conclusions Each species-mapping approach has both advantages and disadvantages. The choice of the most appropriate approach in any given situation depends on the availability of locality records and on the relative importance of mitigating omission and commission errors. Our findings suggest that in most circumstances, the use of distribution modelling has many advantages relative to the other approaches. The priority areas identified in this study should be considered for targeting efforts to conserve Africa freshwater turtles in the coming years. © 2011 Blackwell Publishing Ltd.


Bombi P.,SPACEnvironment | Bologna M.A.,Third University of Rome
Animal Conservation | Year: 2012

For planning practical measures aimed at biodiversity protection, conservation priorities must be identified at a local scale. Unfortunately, identifying local conservation priorities requires high-resolution data on species distribution, and these are often unavailable. Atlases of species distribution provide data for several groups of organisms in many different areas but are often too coarse in resolution to provide valuable information. We explored the possibility of cross-scale modelling species distributions and we clarified, for the first time, its effect on prioritization exercises. We used different modelling techniques for scaling down atlas data for Sardinian reptiles, validated the outcomes with detailed, field-sampled data, and compared conservation priorities deriving from atlas maps and downscaled models. Doing this, we obtained as a further result the identification of priority species and areas for future conservation strategies. Our results encourage us to experiment further with this approach. Through the downscaling procedure, we obtain high-resolution models with strong variations in predictive performances, although most of the models show satisfactory/excellent scores. This testifies that low-resolution data can be downscaled maintaining low rates of omission and commission errors. Increasing the resolution of distribution maps used for prioritization influences the spatial patterns of priority but does not modify the evaluation of species representation. Overall, we show that atlases can meet the large demand for distribution data by decision makers if appropriate downscaling procedures are adopted. In addition, we provide practical instruments for the conservation of reptiles in Sardinia by identifying priority species and areas that require strict management. © 2012 The Zoological Society of London.


Vignoli L.,Third University of Rome | Vignoli L.,CNRS Center of Evolutionary and Functional Ecology | Bombi P.,SPACEnvironment | Bologna M.A.,Third University of Rome | Capizzi D.,Regione Lazio
Italian Journal of Zoology | Year: 2013

Faunistic inventories of particular regions would provide essential datasets for conservation and resource management, but often data are not evenly distributed through the space and time as a consequence of an unequal sampling effort. Therefore, to accurately estimate species diversity it is necessary to minimize this potential confounding effect embedded within most existing datasets. In this study, we identified as high-priority conservation targets areas of high-value species diversity of amphibians in Latium (Central Italy), by illustrating a methodology to generate biodiversity patterns from very heterogeneous datasets, which accounts for the relationships between species richness and sampling effort. We analyzed 6656 data records collected from 1991-2011, which were assigned to the corresponding 10 × 10 km cell of the UTM grid. In order to remove the bias introduced by the differential field effort across cells, we used regression analyses after applying a curve estimation procedure. Then, we validated the best regression model by comparing species richness estimated using this model against that obtained using rarefaction curves. Our results show that the use of residuals can be a suitable approach for controlling the influence of sampling effort on the observed species richness except in a very unequal distribution of the records. Indeed, residuals can be calculated for any cells, irrespective of the observation effort, while when using rarefaction curves a relatively high number of records per cell is required. Finally, when contrasting the amphibian diversity pattern with the existing network of protected areas, several conservation gaps are identified in Latium, especially in mountainous areas. © 2013 Unione Zoologica Italiana.


D'Amen M.,CNR Institute of Agro-environmental and Forest Biology | D'Amen M.,Centro Nazionale Biodiversita Forestale Bosco Fontana | Bombi P.,SPACEnvironment | Campanaro A.,Centro Nazionale Biodiversita Forestale Bosco Fontana | And 5 more authors.
Animal Conservation | Year: 2013

Read the Commentaries on this Feature Paper: Institutional vertebratism hampers insect conservation generally; not just saproxylic beetle conservation; Knowledge gaps in protected area effectiveness Response from the authors: Possible directions in the protection of the neglected invertebrate biodiversity Up to now, global conservation priorities are far from incorporating megadiverse invertebrate taxa. Thus, an important emerging field in biological conservation is how we might manage landscape to preserve insects. In this study, we analyze the efficacy of Italian reserve network for protecting multiple saproxylic beetles, considering both nationally designated areas and Natura 2000 sites. We selected 150 species inhabiting the Italian territory from the European Red List for saproxylic beetles, on the basis of distribution data availability. For each species, a vulnerability score was assigned according to their Red List status, and the species' distributions data were used to perform an irreplaceability analysis. Our analyses show that conservation targets based on geographic range extent are achieved for only 7% of the considered species. We find that 13 species are not represented in any protected area: among these, two click beetle species (Elateridae) are listed in the International Union for Conservation of Nature threatened categories (i.e. Ampedus quadrisignatusEN and AmpedusbrunnicornisVU). Our analyses on protected area effectiveness for the conservation of saproxylic beetles showed that nationally designated protected areas are more irreplaceable than a random selection of cells. Surprisingly, the addition of Natura 2000 sites did not improve the species representation. Moreover, these reserves include sites that are not more irreplaceable than a random selection of cells. We identify some currently unprotected areas that protection could prevent from future extinctions and ensure a favorable conservation status of saproxylic beetles. In particular, we find an important stronghold for beetle conservation, which obtained a high irreplaceability score, in the Adige river basin. We recommend the designation of new reserves in this area to complement the existing network and to help guarantee invertebrate saproxylic fauna protection. Animal Conservation © 2013 The Zoological Society of London.


Bombi P.,SPACEnvironment | D'Amen M.,SPACEnvironment
Journal of Biogeography | Year: 2012

Aim Conservation managers are increasingly looking for modelled projections of species distributions to inform management strategies; however, the coarse resolution of available data usually compromises their helpfulness. The aim of this paper is to delineate and test different approaches for converting coarse-grain occurrence data into high-resolution predictions, and to clarify the conceptual circumstances affecting the accuracy of downscaled models. Location We used environmental data from a real landscape, southern Africa, and simulated species distributions within this landscape. Methods We built 10 virtual species at a resolution of 5arcmin, and for each species we simulated atlas range maps at four decreasing resolutions (15, 30, 60, 120arcmin). We tested the ability of three downscaling strategies to produce high-resolution predictions using two modelling techniques: generalized linear models and generalized boosted models. We calibrated reference models with high-resolution data and we compared the relative reduction of predictive performance in the downscaled models by using a null model approach. We also estimated the applicability of downscaling procedures to different situations by using distribution data for Mediterranean reptiles. Results All reference models achieved high performance measures. For all strategies, we observed a reduction of predictive performance proportional to the degree of downscaling. The differences in evaluation indices between reference models and downscaled projections obtained from atlases at 15 and 30arcmin were never statistically significant. The accuracy of projections scaled down from 60arcmin largely depended on the combination of approach and algorithm adopted. Projections scaled down from 120arcmin gave misleading results in all cases. Main conclusions Moderate levels of downscaling allow for reasonably accurate results, regardless of the technique used. The most general effect of scaling down coarse-grain data is the reduction of model specificity. The models can successfully delineate a species' environmental association up until a 12-fold downscaling, although with an increasing approximation that causes the overestimation of true distributions. We suggest appropriate procedures to mitigate the commission error introduced by downscaling at intermediate levels (approximately 12-fold). Reductions of grain size >12-fold are discouraged. © 2011 Blackwell Publishing Ltd.

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