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Assessing the response of ground-dwelling beetles communities to different land-uses in mediterranean cork oak systems
No full textStudying of macroarthropods communities in different land-use systems may be widely useful in defining management strategies in Mediterranean forests, mainly due to their sensitivity to human impact. This aspect is really interesting in agroforestry systems, where resources shall be managed in terms of ecological and functional sustainability. In our study, we assessed the response of beetles communities at low taxonomical resolution to different Mediterranean cork oak land-use systems. Spatial variation of dung-beetles communities was also analyzed because of their potential role as ecological indicators in grazed areas. We selected twenty-two sites in the northern part of Sardinia (Italy) where beetles were sampled by using a total of 220 pitfall traps. In addition, in each site, a number of environmental variables related to cork oak woodlands structure and land use were measured. During the entire sampling period a total of 4550 individuals belonging to 47 families of beetles were captured. Multivariate analysis performed on ground-dwelling beetles data showed a distinct separation in terms of assemblages between grazed and low-managed sites (stress value = 0.18). Environmental variables significant affecting beetles assemblages were the sheep grazing, the average diameter of cork oak trees, the altitude and the degree of shrubs cover. Further, constrained multivariate analysis indicated the significance of grazing, by both large (F = 2.36, p = 0.03) and small domestic herbivores (F = 3.88, p = 0.002), and altitude (F = 3.54, p = 0.005) as variables determining dung beetles assemblages. Our results support the reliability of ground-dwelling beetles as valuable tool both to detect environmental changes in Mediterranean cork oak woodlands and to define management strategies useful to increase the resilience of cork oak agroforestry systems under future global change scenarios
La canapa nella riqualificazione di suoli contenenti metalli pesanti a Villadossola: vantaggi e prospettive
No full textNot availableLe piante rivestono un ruolo fondamentale nella produzione di ossigeno e nel sequestro di anidride carbonica, sono parte integrante dell\u27ecosistema e mettono in relazione l\u27atmosfera e tutto ci? che ? disperso in essa con il suolo e l\u27acqua. La canapa (Cannabis sativa L.), una specie erbacea di coltivazione annuale appartenente alla famiglia delle Cannabaceae, suscita particolare interesse per le sue numerose funzioni, la pi? nota consiste nella produzione di materie prime alimentari per uso umano e zootecnico (foglie, fiori, frutti, semi, germogli, fibra), nella produzione di fibre tessili e bioplastiche, pannelli isolanti, biodiesel e/o bioetanolo, legna, pellet etc. (Bouloc et al., 2013). Inoltre, l\u27utilizzo delle piante per la riqualificazione di ambienti degradati e/o inquinati (phytoremediation) suscita grande attenzione per il basso impatto ambientale e costi di intervento relativamente ridotti. La phytoremediation, termine anglosassone ormai utilizzato anche nella lingua italiana, consiste nell\u27utilizzo di piante con particolari capacit? di contenere, rimuovere o degradare i contaminanti presenti nei suoli, nei sedimenti e nelle acque. Le tecnologie che utilizzano piante, chiamate anche "fitotecnologie", possono essere impiegate per rimuovere o contenere inquinanti inorganici (metalli pesanti: piombo (Pb), nichel (Ni), zinco (Zn) etc., elementi radioattivi: cesio (Cs), uranio (U) etc.); per rimuovere o degradare inquinanti organici (idrocarburi policiclici aromatici (IPA), composti clorurati, etc.); possono essere utilizzate per riqualificare substrati solidi (suoli e sedimenti) e substrati liquidi (acque superficiali e falde sotterranee
Mediterranean river biomonitoring in Central Italy: Diatom biodiversity and characterization of communities
No full textAbstract In compliance with the European and Italian regulations, the Environmental Protection Agency of Umbria Region (ARPA Umbria) defined specific river monitoring programs and networks based on river type definition, human pressures and risk analysis. The Umbria Region lies in Central Italy and it can be split into three hydro-ecoregions belonging to the Mediterranean area. Data on diatom community composition were collected in five different Mediterranean macrotypes (M1-M5) throughout the diatom-based river monitoring network that is composed by 52 sampling stations in 36 watercourses. The main aim of this study was to characterise and to analyse diatom diversity across the different regional river macrotypes. Specifically, we investigated if: i) there were differences in species diversity (species richness and Shannon Index) among macrotypes; ii) there was difference in three water quality indexes (ICMi, IPS, and TI) among sites; and iii) there was a relationship between the observed ICMi, IPS and TI value and the diatom diversity. Two-hundred diatom species and varieties were identified, and the number of species per sampling station ranged from a minimum of 10 to a maximum of 38 species. The most frequent and abundant species were Amphora pediculus, Achnanthidium minutissimum, Navicula cryptotenella, Nitzschia dissipata, and each macrotype showed some peculiar species. The ecological status evaluation based on Intercalibration Common Metric Index (ICMi) classified 69% of the water bodies in high or good class. Significant differences in diversity and ICMi value among stream macrotypes were found, with M4 (small and medium mountain) and M5 (small, lowland, temporary) typologies showing the lowest species richness, and with M5 showing the lowest Shannon Index. Conversely, M2 (small and medium lowland) and M5 showed the highest ICMi value. Lastly, significant correlations between Shannon Index and the ICMi, IPS and TI indexes were found
PLATINUM: A new Framework for Planning and Acting
No full textThis paper presents a novel planning framework, called PLATINUm that advances the state of the art with the ability of dealing with temporal uncertainty both at planning and plan execution level. PLATINUm is a comprehensive planning system endowed with (i) a new algorithm for temporal planning with uncertainty, (ii) heuristic search capabilities grounded on hierarchical modelling and (iii) a robust plan execution module to address temporal uncertainty while executing plans. The paper surveys the capabilities of this new planning system that has been recently deployed in a manufacturing scenario to support Human- Robot Collaboration
How "deep" is learning word inflection?
No full textMachine learning offers two basic strategies for morphology induction: lexical segmentation and surface word relation. The first one assumes that words can be segmented into morphemes. Inducing a novel inflected form requires identification of morphemic constituents and a strategy for their recombination. The second approach dispenses with segmentation: lexical representations form part of a network of associatively related inflected forms. Production of a novel form consists in filling in one empty node in the network. Here, we present the results of a recurrent LSTM network that learns to fill in paradigm cells of incomplete verb paradigms. Although the process is not based on morpheme segmentation, the model shows sensitivity to stem selection and stem-ending boundaries.La letteratura offre due strategie di base per l\u27induzione morfologica. La prima presuppone la segmentazione delle forme lessicali in morfemi e genera parole nuove ricombinando morfemi conosciuti; la seconda si basa sulle relazioni di una forma con le altre forme del suo paradigma, e genera una parola sconosciuta riempiendo una cella vuota del paradigma. In questo articolo, presentiamo i risultati di una rete LSTM ricorrente, capace di imparare a generare nuove forme verbali a partire da forme gi? note non segmentate. Ciononostante, la rete acquisisce una conoscenza implicita del tema verbale e del confine con la terminazione flessionale
Data distribution in public veterinary service: health and safety challenges push for context-aware systems
No full textToday\u27s globalised and interconnected world is characterized by intertwined and quickly evolving relationships between animals, humans and their environment and by an escalating number of accessible data for public health. The public veterinary services must exploit new modeling and decision strategies to face these changes. The organization and control of data flows have become crucial to effectively evaluate the evolution and safety concerns of a given situation in the territory. This paper discusses what is needed to develop modern strategies to optimize data distribution to the stakeholders
Validation of PROBA-V GEOV1 and MODIS C5 & C6 fAPAR Products in a Deciduous Beech Forest Site in Italy
No full textThe availability of new fAPAR satellite products requires simultaneous efforts in validation to provide users with a better comprehension of product performance and evaluation of uncertainties. This study aimed to validate three fAPAR satellite products, GEOV1, MODIS C5, and MODIS C6, against ground references to determine to what extent the GCOS requirements on accuracy (maximum 10% or 5%) can be met in a deciduous beech forest site in a gently and variably sloped mountain site. Three ground reference fAPAR, differing for temporal (continuous or campaign mode) and spatial sampling (single points or Elementary Sampling Units-ESUs), were collected using different devices: (1) Apogee (defined as benchmark in this study); (2) PASTIS; and (3) Digital cameras for collecting hemispherical photographs (DHP). A bottom-up approach for the upscaling process was used in the present study. Radiometric values of decametric images (Landsat-8) were extracted over the ESUs and used to develop empirical transfer functions for upscaling the ground measurements. The resulting high-resolution ground-based maps were aggregated to the spatial resolution of the satellite product to be validated considering the equivalent point spread function of the satellite sensors, and a correlation analysis was performed to accomplish the accuracy assessment. PASTIS sensors showed good performance as fAPARPASTIS appropriately followed the seasonal trends depicted by fAPARAPOGEE (benchmark) (R2 = 0.84; RMSE = 0.01). Despite small dissimilarities, mainly attributed to different sampling schemes and errors in DHP classification process, the agreement between fAPARPASTIS and fAPARDHP was noticeable considering all the differences between both approaches. The temporal courses of the three satellite products were found to be consistent with both Apogee and PASTIS, except at the end of the summer season when ground data were more affected by senescent leaves, with both MODIS C5 and C6 displaying larger short-term variability due to their shorter temporal composite period. MODIS C5 and C6 retrievals were obtained with the backup algorithm in most cases. The three green fAPAR satellite products under study showed good agreement with ground-based maps of canopy fAPAR at 10 h, with RMSE values lower than 0.06, very low systematic differences, and more than 85% of the pixels within GCOS requirements. Among them, GEOV1 fAPAR showed up to 98% of the points lying within the GCOS requirements, and slightly lower values (mean bias = ?\u270.02) as compared with the ground canopy fAPAR, which is expected to be only slightly higher than green fAPAR in the peak seaso
Potential and realized connectivity of the seagrass Posidonia oceanica and their implication for conservation
No full textAim: Connectivity assessments are crucial to large-scale conservation planning, in particular for establishing and monitoring connected networks of marine protected areas (MPAs). Using biophysical modelling and genetic analyses, we assessed potential and realized connectivity among MPA populations of a benthic foundation species, the Mediterranean endemic seagrass Posidonia oceanica. Location: Adriatic and Ionian seas (central Mediterranean). Methods: We assessed potential and realized connectivity among eight P. oceanica meadows, mostly located in MPAs. Potential connectivity was assessed over a time horizon of 10 years via an individual-based biophysical model whose physical component relies on fine-scale spatio-temporal ocean circulation fields. Genetic assessments of realized connectivity were carried out by means of a set of 14 neutral microsatellite loci, as well as a larger dataset of 19 loci including outlier loci that did not conform to expectations under neutrality. Results: Our findings point out a relatively high potential connectivity through long-range dispersal of floating fruits. Genetic connectivity analyses show a complex scenario with an apparent lower realized connectivity. The P. oceanica meadow within Torre Guaceto MPA (TOG), a well-enforced MPA within our study area, showed one of the highest levels of genotypic richness, indicative of high levels of sexual reproduction and/or recruitment of foreign genotypes. Both biophysical modelling and population genetics indicate that TOG is important to ensure the viability of the species at the local scale, and does likely play a key role as a source of propagules for the Whole Adriatic area. Main conclusions: Our results show that realized dispersal does not necessarily match with the potential for dispersal. Still, both genetic and physical connectivity analyses show good agreement in identifying hotspots of connectivity. Such information can guide management of networks of MPAs and advance conservation of marine biodiversity
The architecture challenge: Future artificial-intelligence systems will require sophisticated architectures, and knowledge of the brain might guide their construction
No full textIn this commentary, we highlight a crucial challenge posed by the proposal of Lake et al. to introduce key elements of human cognition into deep neural networks and future artificial-intelligence systems: the need to design effective sophisticated architectures. We propose that looking at the brain is an important means of facing this great challenge