Search results for "Fragment"
showing 10 items of 1612 documents
Habitat fragmentation and anthropogenic factors affect wildcat Felis silvestris silvestris occupancy and detectability on Mt Etna
2019
International audience; Knowledge of patterns of occupancy is crucial for planning sound biological management and for identifying areas which require paramount conservation attention. The European wildcat Felis silvestris is an elusive carnivore and is classified as ‘least concern' on the IUCN red list, but with a decreasing population trend in some areas. Sicily hosts a peculiar wildcat population, which deserves conservation and management actions, due to its isolation from the mainland. Patterns of occupancy for wildcats are unknown in Italy, and especially in Sicily. We aimed to identify which ecological drivers determined wildcat occurrence on Mt Etna and to provide conservation actio…
Multilocus sequence typing confirms the close genetic inter-relatedness between three distinct flavescence doree phytoplasma strain clusters and grou…
2007
ABSTRACT Vineyards of southern France and northern Italy are affected by the flavescence dorée (FD) phytoplasma, a quarantine pathogen transmitted by the leafhopper of Nearctic origin Scaphoideus titanus . To better trace propagation of FD strains and identify possible passage between the vineyard and wild plant compartments, molecular typing of phytoplasma strains was applied. The sequences of the two genetic loci map and uvrB - degV , along with the sequence of the secY gene, were determined among a collection of FD and FD-related phytoplasmas infecting grapevine, alder, elm, blackberry, and Spanish broom in Europe. Sequence comparisons and phylogenetic analyses consistently indicated the…
Sensitive measure of prevalence and parasitaemia of haemosporidia from European blackbird (Turdus merula) populations: value of PCR-RFLP and quantita…
2006
8 pages; International audience; Haemosporidian parasites are common in birds in which they act as an important selective pressure. While most studies so far have focused on the effect of their prevalence on host life-history traits, no study has measured the effect of parasitaemia. We developed molecular methods to detect, identify and quantify haemosporidia in 2 natural populations of the Blackbird Turdus merula. Three different parasite genotypes were found - 1 Haemoproteus and 2 Plasmodium. A PCR-RFLP screening revealed that only approximately 3% of blackbirds were free of parasites, compared to the 34% of uninfected birds estimated by blood smear screening. A quantitative PCR (q-PCR) a…
Conservation implications of change in antipredator behavior in fragmented habitat: Boreal rodent, the bank vole, as an experimental model
2015
Abstract Habitat fragmentation is known to cause population declines but the mechanisms leading to the decline are not fully understood. Fragmentation is likely to lead to changes in predation risk, which may cause behavioral responses with possible population level consequences. It has recently been shown that the awareness of predator presence, resulting in a fear response, strongly affects behavior and physiology of the prey individuals. Costs arising from fear may be as important for the prey population size as the direct killing of prey. We tested how predation risk in the form of scent of a specialist predator, the least weasel (Mustela nivalis nivalis), affects bank vole (Myodes glar…
Genetic structure of a European forest species, the edible dormouse ( Glis glis ): a consequence of past anthropogenic forest fragmentation?
2019
International audience; The genetic structure of forest animal species may allow the spatial dynamics of the forests themselves to be tracked. Two scales of change are commonly discussed: changes in forest distribution during the Quaternary, due to glacial/interglacial cycles, and current fragmentation related to habitat destruction. However, anthropogenic changes in forest distribution may have started well before the Quaternary, causing fragmentation at an intermediate time scale that is seldom considered. To explore the relative role of these processes, the genetic structure of a forest species with narrow ecological preferences, the edible dormouse (Glis glis), was investigated in a set…
Can green infrastructure help to conserve biodiversity?
2017
The gradually decreasing connectivity of habitats threatens biodiversity and ecological processes valuable to humans. Green infrastructure is promoted by the European Commission as a key instrument for the conservation of ecosystems in the EU biodiversity strategy to 2020. Green infrastructure has been defined as a network of natural and semi-natural areas, designed and managed to deliver a wide range of ecosystem services. We surveyed Finnish experts' perceptions on the development of green infrastructure within the existing policy framework. Our results show that improving the implementation of existing conservation policy instruments needs to be an integral part of developing green infr…
Stand out from the Crowd: Small-Scale Genetic Structuring in the Endemic Sicilian Pond Turtle
2020
The geographical pattern of genetic diversity was investigated in the endemic Sicilian pond turtle Emys trinacris across its entire distribution range, using 16 microsatellite loci. Overall, 245 specimens of E. trinacris were studied, showing high polymorphic microsatellite loci, with allele numbers ranging from 7 to 30. STRUCTURE and GENELAND analyses showed a noteworthy, geographically based structuring of the studied populations in five well-characterized clusters, supported by a moderate degree of genetic diversity (FST values between 0.075 and 0.160). Possible explanations for the genetic fragmentation observed are provided, where both natural and human-mediated habitat fragmentation o…
Effects of traditional coppice practices and microsite conditions on tree health in a European beech forest at its southernmost range
2016
Abstract: European beech (Fagus sylvatica) grows at the southern limit of its range in the mountain-Mediterranean vegetation belt up to the timberline. The southernmost beech forests of Sicily (southern Italy) show peculiar ecological, structural and silvicultural characteristics, growing in fragmented and isolated stands near the timberline and in topographically marginal unfavorable habitats. Past silvicultural practices increased the heterogeneity of stand structure at these sites. We compared stand structural characteristics and tree health in coppice-cut and control beech stands with respect to the local topographic gradient (bottom, slope and ridge) and canopy cover (clearing/border v…
Assessing the capacity of different urban forms to preserve the connectivity of ecological habitats
2011
International audience; This paper addresses the relationship between anthropogenic forest habitat fragmentation and the form of urban patterns. Using a two-step methodology we first generate 40 theoretical residential development scenarios following a repeatable procedure; the simulated urban forms are either moderately compact or fractal. Then, we compare the scenarios according to the functional connectivity of the remaining forest habitat using a graph-based approach. The methodology is applied to the urban region of Besançon (France), where forest surfaces are considered as a generic habitat for several animal species. Results obtained show that fractal scenarios of residential develop…
QTLs for organoleptic quality in fresh market tomato
1998
The organoleptic quality of tomato fruit is determined by many characters. Therefore, plant breeders often find difficulties to improve such a characteristic. A program of QTL detection for physical, chemical and sensorial traits has been achieved, in order to understand the genetic determinism of tomato organoleptic quality. One hundred and forty-four recombinant inbred lines (RILs), derived from an intraspecific cross, were analyzed with segregating molecular markers. An almost saturated map was constructed with RFLP, AFLP and RAPD marker. The RILs were also evaluated for fruit chemical (sugar, pigment and acid contents) and physical traits (color, firmness and fruit size). These analyses…