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L\u27occupazione del territorio da parte di Lymantria dispar (Linnaeus) (Lepidoptera Erebidae) come indice di previsione della probabilit? di danno
No full textIn Sardinia (Italy) the population abundance of the defoliator gypsy moth Lymantria dispar (L.) (Lepidoptera Erebidae) has been regularly sampled for over thirty years by counts of egg masses. Although this monitoring activity allows annual identification of the areas with the highest abundance of infestation, the identification of areas to be treated have been defined exclusively according to the experience gained over the years by the operators. To overcome the limitation of this empirical approach we have developed an objective method supporting decision making based on the relationship between the percentage of infested sites and the intensity of defoliation. For this purpose the radius of annual gypsy moth expansion was estimated in a cork oak district: the estimated value was ca. 6 km per year. This value was used to calculate the percentage of sites occupied by at least 1 egg mass within that radius. A generalized linear model was used to evaluate the statistical significance of the relationship between percentage of occupied sites and presence of damage. According to what we know from literature a monitoring site was considered damaged when defoliation level of foliage was greater than 50%. We then used the historical series of data to calculate the probability that a defoliation event would occur according to the estimated model. The logit model confirmed the validity of the predictor with respect to the presence of damage, with a general accuracy greater than 90%. The results suggest a revision of the sampling protocol used thus far, which requires a particularly costly and prolonged sampling effort. The method described herein should allow easier identification of forest areas exposed to damage and timelier planning of control interventions
Analisi della diversit? genetica di popolazioni di Quercus pubescens della Sardegna mediante marcatori SSR nucleari e plastidiali
No full textAnalysis of genetic diversity in natural Quercus pubescens populations from Sardinia through nuclear and chloroplast SSR marker
Lake Orta chemical status 25 years after liming: problems solved and emerging critical issues
Get PDFLake Orta, located in Piedmont, northwestern Italy, has been severely affected by industrial pollution since the 1930s. A successful liming intervention, performed in 1988-1990, returned pH levels in the lake to neutrality, and accelerated the reduction of aqueous trace metal concentrations. In this paper, we present an update knowledge of the chemical status of Lake Orta, focusing on the data collected from 1990 to 2014. In this period we sampled the lake at its deepest point (Qualba station), on a monthly (1990-2000) or seasonal (since 2001) basis. Samples were collected at nine depths through the water column, and analyzed for pH, conductivity, alkalinity, major ions, nutrients, and trace metals. Collectively, these data allowed us to evaluate the long-term response of the lake to the restoration treatment, with particular regard to its acid-base status; they also provided insights into emerging or potential critical issues, including eutrophication and re-suspension of trace metals that still linger in the lake. Furthermore, the evaluation of the present chemical condition of the lake is a precondition for any successive restoration measure, such as fish introduction. The recent data confirmed the lake\u27s water quality has recovered, i.e. returned to a pre-pollution chemical state. Lake water values of pH and concentrations of ammonium, sulphate and base cations have stabilized. Alkalinity and nitrate concentrations are also expected to reach stable level in the next few years. Levels of nitrate, reactive silica, and phosphorus compounds are now regulated by algal uptake, providing indirect evidence of a partial biological recovery. For instance, both the inter-annual average decline and the reappearance of a seasonal signal in silica confirmed the presence of a stable diatom community. The lake is presently oligotrophic, and concentrations of both N and P compounds are steady and low throughout the year. However, a monthly check of nutrient levels of the lake and inflowing waters is recommended. The monitoring of base chemical variables, major ions and trace metals should be maintained to assess the overall status of the ecosystem in response to various drivers, including climate change
Rotifers in Lake Orta: a potential ecological and evolutionary model system
Get PDFLake Orta experienced for a few decades a unique history of chronic pollution, with extreme changes in pH and copper concentration. Currently, the lake has recovered to its almost pristine oligotrophic conditions, but its sediments still preserve the record of all the changes that happened since the establishment of the first polluting factories in the 1920s, through to the liming activities in 1989-1990, and to the recovery phase that is still going on. Here we review the current knowledge for Lake Orta regarding rotifers, a diverse component of the zooplankton of the lake, through studies on living organisms and on their resting stages accumulated in the sediments. We also report a brief review of what is known in general on the effects of changes in pH and copper concentration on rotifers at the population, species and community level, providing expectations for such effects on the rotifers of Lake Orta. Then, we conclude our review with a perspective on the potential use of rotifers hatched from the resting stages in the sediment of Lake Orta with the description of experiments that can be performed in the future in the framework of resurrection ecology, in order to understand the mechanisms of past and future changes in the environment
Open Dialogue in the Italian mental health services: transferability and evaluation of efficacy in the Italian context.
No full textThis contribution presents the state of the art of the Italian project on Open Dialogue
Distributed design for fair coexistence in TVWS
No full textVery recently, regulatory bodies worldwide started to approve the opportunistic access of unlicensed networks to the TVWS spectrum. Hence, in the near future, multiple heterogeneous and independently-operated unlicensed networks will coexist within the same geographical area over shared TVWS. Nevertheless, the coexistence among heterogeneous unlicensed networks over TVWS represents an open problem, and innovative solutions for handling the coexistence interference are needed to fully unleash the TVWS potentials. Hence, in this paper, we design a coexistence strategy for TVWS scenarios with the following attractive features: i) fully distributed, i.e., it avoids the need of centralized interference management; ii) over-the-air communications free, i.e., it avoids the need of direct communications among the heterogeneous networks; iii) adaptive to the time- and space-dynamics of the coexistence interference; iv) selfless, i.e., it allows a fair TVWS spectrum sharing by accounting for the communication demands of each unlicensed network. These attractive features are obtained by designing a coexistence strategy based on a system of multi-dimensional ordinary differential equations, and by incorporating the tradeoff between selfish bandwidth maximization and fair spectrum allocation within the system dynamics. Performance evaluation is conducted through numerical simulations, and the results confirm the attractive features of the proposed coexistence strategy
Il Carbonio organico nel Lago Maggiore: tendenza evolutiva, origine e caratteristiche qualitative nel triennio 2013-2015
No full textNot availableRicerche sull\u27evoluzione del Lago Maggiore. Aspetti limnologici. Programma triennale 2013-2015. Campagna 2015 e rapporto triennale 2013-2015. Il Carbonio organico nel Lago Maggiore: tendenza evolutiva, origine e caratteristiche qualitative nel triennio 2013-2015. TOC (Total Organic Carbon). TEP (Transparent Exopolymeric Particels). CDOM (Chromophoric Dissolved Organic Matter
Indagini su DDT e sostanze pericolose nell\u27ecosistema del Lago Maggiore. Programma 2013-2015. Rapporto annuale 2015 e finale 2013-2015. Riassunto
No full textNot availableRiassunto delle attivit? all\u27inizio del volume "Indagini su DDT e sostanze pericolose nell\u27ecosistema del Lago Maggiore. Programma 2013-2015. Rapporto annuale 2015 e finale 2013-201"
