Search results for "Conservation"
showing 10 items of 2328 documents
Relationship between recruitment and mother plant vitality in the alien species Acacia cyclops A. Cunn. ex G. Don
2014
Acacia cyclops is a widespread invader in Mediterranean-climate regions. However, although its naturalization in the Mediterranean Basin dates back only a few years ago, and the invasion process has not been studied hitherto. We investigated seedlings recruitment strategy adopted by A. cyclops in a small island (Lampedusa, Italy) where its natural regeneration was strictly confined under mother plants canopy. Healthy plants (DCP), plants at incipient senescence (SCP) and dead plants (DP) were distinguished according to vitality and canopy status. Living plants were also characterized in relation to leaf C and N isotope composition. Regeneration pattern (seedlings and saplings abundance) was…
Patterns of algal recovery and small-scale effects of canopy removal as a result of human trampling on a Mediterranean rocky shallow community.
2004
The ecological importance of marine algae is widely known but in shallow coastal areas the composition and structure of algal communities may be affected by different human activities. Recovery from different trampling disturbances of two competing morphological groups (i.e. macroalgae and algal turfs) and effects of macroalgal canopy removal on the dominant associated fauna were examined using controlled trampling experiments. Six months after trampling disturbance was removed, the two morphological groups closely resembled control (untrampled) conditions, both in terms of cover and canopy (%). In particular, macroalgal recovery seemed to be very rapid: the higher the impact on the system …
Effects of spatial scale and vegetation cover on predation of artificial ground nests
1995
Scale-dependent effects of landscape heterogeneity on predation of artificial ground nests were studied. Two spatial scales were selected: landscape grain size and single stand size. The landscape types did not differ from each other in their total predation intensity. Depredation was highest in larger stands in all the landscape types studied and the highest predation rate was detected in the largest stands within the most fragmented landscapes. This is possibly due to concentration of rodent-eating predators from surrounding open areas into large stands in the study year when their main prey, voles, crashed. In crash years, alternative predation on e.g. forest bird nests may play an impor…
A new species of Capparis L. (Capparaceae) from Sumatra (Indonesia)
2021
A new species of Capparis L., C. irenae Fici, sp. nov., is described and illustrated from Tigapuluh Mts., Riau Province of Sumatra, where it is known from a single locality in forest communities. The new species, belonging to Capparis sect. Monostichocalyx Radlk., is related to C. diffusa Ridl., differing in several characters as the glabrous twigs, longer petioles and leaves, flowers arranged in racemes with cataphylls at the base, longer petals hairy outside and longer filaments. Its affinities with other related taxa and its conservation status are discussed. Moreover a distribution map of the new species and an identification key to the species of Capparis recognized in Sumatra are prov…
Capparis tchaourembensis, a new species of Capparaceae from Mayotte, Comororian Archipelago
2011
A new species of Capparis, C. tchaourembensis Fici, is described and illustrated. Its conservation status is assessed and its affinities with related taxa are discussed.
Current Status of and Threats to Sicilian Turtles
2022
Based on the critical review of the literature published in the last 22 years, an attempt was made to evaluate the current knowledge gap on the distribution and status of the native Testudines taxa occurring in Sicily (namely Caretta caretta, Emys trinacris, and Testudo hermanni hermanni), as well as the available knowledge of the only non-native species with putative viable populations occurring on the island, i.e., Trachemys scripta. Summarizing the current information, all of the Testudines species occurring in Sicily showed a fragmented and incompletely-known distribution, and only scarce data are available about their phenology. Moreover, despite their inclusion of international and na…
Distribution, ecology, vegetation and conservation survey on the relictual population ofCarex panormitanaGuss. (Cyperaceae) in Sicily (Italy)
2013
We report the results of research on the Carex panormitana Guss. (Cyperaceae) population in Sicily, carried out within its locus classicus at the Oreto River (Palermo). The survey led to a morphological, biological and autoecological characterization, to the definition of the current distribution in the site, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Critically Endangered (CR), in accordance with the CR B1ab (ii, iii, v) and EN C1 IUCN criteria. Moreover, the phytosociological survey carried out on the meso-hygrophilous vegetation in which the species is dominant a…
On Approximation of Entropy Solutions for One System of Nonlinear Hyperbolic Conservation Laws with Impulse Source Terms
2010
We study one class of nonlinear fluid dynamic models with impulse source terms. The model consists of a system of two hyperbolic conservation laws: a nonlinear conservation law for the goods density and a linear evolution equation for the processing rate. We consider the case when influx-rates in the second equation take the form of impulse functions. Using the vanishing viscosity method and the so-called principle of fictitious controls, we show that entropy solutions to the original Cauchy problem can be approximated by optimal solutions of special optimization problems.
In vitro effects of aminobisphosphonates on Vgamma9Vdelta2 T cell activation and differentiation.
2006
In this study we have evaluated the in vitro effects of four different aminobisphosphonates, alendronate, risedronate, neridronate and zoledronate, on Vγ9Vδ2 T cell activation and differentiation. All tested aminobisphosphonates induce an IL-2-dependent activation and expansion of Vγ9Vδ2 T lymphocytes in primary PBMC cultures of healthy donors. Most notably, they also determine a different distribution of Vγ9Vδ2 T cell subsets, with decrease of Tnaive and TCM cells and increase of TEM and TEMRA Vγ9Vδ2 cells, indicating that in vitro treatment with aminobisphosphonates induces Vγ9Vδ2 T lymphocytes to differentiate towards an effector/cytotoxic phenotype. Accordingly, Vγ9Vδ2 T lymphocytes cu…
Development of a performance threshold approach for identifying the management options for stabilisation/solidification of lead polluted soils
2014
Two soils spiked with lead at different rates were stabilised/solidified using Portland cement and fy ash at different soil:binder ratios, and tested for their setting time, unconfined compressive strength, leachability and durability. A performance threshold approach was used in order to identify optimal management options for the products of the S/S treatment. Results show that soil texture, percentage of binders and lead concentration play an important part in the treatment, significantly influencing the performance of the resulting products in terms of curing, compressive strength and durability. Pb soil concentrations higher than 15000 mg kg-1 were found to heavily reduce the applicab…