Riviste Online SApienza - R.O.SA - 2 (Sapienza University of Rome)
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The importance of beech forests as reservoirs of moth diversity in Mediterranean Basin (Lepidoptera)
Get PDFStudy analyzes the macrolepidoptera assemblages in beech woodlands of the Orsomarso Mountains (Pollino National Park, Southern Italy) to assess the role of beech forests in preserving diversity in Mediterranean Basin. Research was run between 2015 and 2016 in 15 stands representative of the main successional stages of forest maturation, placed between 990 and 1,475 meters of elevation. Monthlybased sampling was performed using UV-LED light traps. A total of 33,957 individuals belonging to 410 species was collected. The community is rich and the most abundant and characteristic species (Eilema lurideola, Operophtera fagata, Campaea margaritata) are almost all trophically linked to broadleaves or lichens. The community structure appears fairly constant and recognizable in all stands over the two years of sampling. Young beech forests hosted the greatest number of species compared to other forest maturation stages, though the difference is small. The greatest differences in the community structure are found in the clearings, where generalist and/or related to the herbaceous layer species are mostly represented. Biogeographically widely distributed species prevail, 87% of them having European or Asian-European distribution. There are a number of species of faunistic interest, among which Perizoma juracolaria, Chelis maculosa, Tiliacea citrago, Poecilocampa populi, Triphosa dubitata, Sideridis reticulata, Nebula senectaria, including 13 Italian endemics such as Coenotephria antonii. Populations of many species show significant genetic diversities compared to other European populations. The Orsomarso Mountains beech forests represent an important biodiversity reservoir, even at the genetic level, and show a good degree of naturalness
Enhanced one-way coupled swe-de model for floating body transport
Get PDFModelling the transport of floating bodies during floods is a topic that must be considered when dealing with flood risk, but many open issues still exist regarding its implementation. The paper presents an enhanced one-way coupled SWE-DE (Shallow Water Equations-Discrete Element) model, focusing on to the algorithm for the rigid body localization and on the interpolation of the flow velocity distribution along the body. The proposed algorithm leads to a smoother variation of the hydrodynamic coefficients. Moreover, the higher accuracy in assigning the flow velocity, needed to compute the forces on the bodies, reduces the dependence on the relative size of the cells and objects. A laboratory case has been used to validate the model in which some rectangular obstacles are present. Obstacles were represented by modelling them as solid walls or by increasing the Manning roughness coefficient. The influence of the two schematizations on the flow field and on the transport of a floating cylinder is evaluated. On overall, varying the obstacle roughness coefficient yield trajectories closer to the observed ones, although external factors, such as the effect of cylinder orientation and of collisions with side walls, may occasionally alter the outcome of the simulation
Nanoseismic monitoring for detection of rockfalls: experiments in quarry areas
Get PDFIn the frame of early warning and risk mitigation studies for landslide processes involving rock masses, two quarry areas (Cala Rossa Bay in Sicily and Acuto in Central Italy) were monitored with SNS (Seismic Navigation System) arrays. In this study, 73 rockfalls were simulated by launches of rock blocks. This allowed to perform a back analysis for defining the best seismic velocity model of the subsoil half-space; the records related to each impact caused by the rock block launch were managed by the nanoseismic monitoring approach, varying the velocity model to obtain a theoretical epicentre as close as possible to the actual location of the impact point. In order to evaluate the sensibility of the SNS array, the results obtained by different array apertures and positions were compared in terms of azimuth and distance error with respect to the real epicentres. On the other hand, several natural rockfalls were detected; their analysis allowed to identify areas having higher susceptibility to rockfalls by using the previously calibrated subsoil half-space model. Further studies are required to better define the areas prone to rockfall generation in the considered test sites; nevertheless, the here obtained results show an encouraging perspective about the application of the nanoseismic monitoring with respect to vulnerable infrastructures in rockfall prone areas
Description of three new Paratrichius Janson, 1881, from Indochinese peninsula (Coleoptera: Scarabaeidae, Cetoniinae)
Get PDFA recent increase in quality collecting activities in Laos and Vietnam, particularly by local collectors, has added significantly to our knowledge of the insect faunas in these countries. The genus Paratrichius Janson, 1881 is no exception, new species are being discovered regularly. In the current study, three new species closely related to Paratrichius vicinus (Bourgoin, 1915) are described
Two new species of Chaetocnema Stephens from South Africa (Coleoptera: Chrysomelidae, Galerucinae, Alticini)
Get PDFIn this paper Chaetocnema adamastori sp. nov. and C. saldanhai sp. nov., both from Western Cape Province (Republic of South Africa), are described. The two new species are closely related with C. audisiana Biondi and C. capensis Bryant, respectively. Micrographs of diagnostic characters, including male and female genitalia, are supplied. Ecological data for each species, including habitat preference, host plant and phenology, are also reported
A new species of Teratolytta from Iran, with an updated identification key to the males of this genus (Coleoptera: Meloidae)
Get PDFTeratolytta capillata sp. n., the southernmost representative of the section I of this genus, is described, figured and the diagnostic characters within T. carlae group are listed. An updated identification key to the males of Teratolytta species is also provided
The Swelling and shrinkage properties of clay-rich soils after cement treatment: a microstructural approach
Get PDFThe properties of three expansive clay-rich soils from Algeria, before and after treatment with various quantities of cement was explained using physico-chemical tests. SEM, MIP and XRD as well as the adsorption of methylen blue molecule (Vbs) were carried out to observe the microstructure change under both the short term flocculating effect of Ca2+ and the long term effect of precipitated products during cement hydration (binding effect). The flocculating effect contributed also to the change of proctor optimum characteristics: γd,OPN decreased while wOPN increased with the cement addition. As expected, experimental investigations evidenced a reduction of both the swelling potentials S, the total soil deformation Stot and the swelling pressures σs when the amount of cement increased. S, Stot, σs and the shrinkage limit ws (or the liquid limit LL) versus the added cement followed a third polynomial curve, allowing to establish three swelling zones. An optimum cement content around 7-8% orresponded to the limit between zone II and III. From such limit, a maximum cohesion c’ and friction angle φ’ was reached which corresponded to a significant improvement of mechanical characteristics, while the decrease of Vbs or the maximum water content wmax stopped
Illicit drugs in wastewater tratment plants: occurrence and behaviour
Get PDFThe occurrence of illicit drugs and related metabolites in two wastewater treatment plants (WWTPs) (namely, WWTP-1 and WWTP-2) located in Sicily (island in the South of Italy) is here discussed. The following illicit drugs have been investigated: methamphetamine, cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA), methadone (METH), 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), 3,4-methylenedioxy amphetamine (MDA); 3,4-methylenedioxy ethylamphetamine (MDEA), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) and Benzoylecgonine (BEG). BEG, COC, MOR and THC-COOH have the highest concentration for both WWTPs. Inside WWTP-1 negative removal efficiencies were sometimes obtained. For WWTP-2 found for BEG (77.85%), COC (92.34%), CODEINE (64.75%), MOR (90.16%) and THC-COOH (68.64%)
Some proposals for a democratic and progressive EMU
No full textThe paper deals first with the asymmetries existing in the European Monetary Union (EMU) between the peripheral countries and core countries. Macroeconomic imbalances in terms of public budget and current account descended from these asymmetries and from the EMU institutional set-up. The paper also investigates the theoretical inspirations – based on monetarist and rational expectations theories - and the country and sectional interests underlying this set-up. Theoretical progress has however intervened in the last couple of decades that makes this set up obsolete. The need for new institutions then arises, even if their realization is contrasted especially by core countries. After designing the desirable goals of a new Monetary Union, the paper indicates the need for a more democratic Union and a possible articulation of new common institutions. The possibility of a country’s exit from the Union and the costs and benefits related to this process are also discussed. Even if net costs might derive in the short run, the threat of exit can add to its bargaining power subject to the hegemony of core countries