209 research outputs found

    Incendi, cultura dell’ambiente e selvicoltura in Sicilia1

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    Si illustrano strumenti e metodi per la prevenzione degli incendi e per la formazione di una cultura attenta alla conservazione e alla valorizzazione dell’ambiente boschivo, offrendo anche alcune riflessioni sul loro impatto economic

    Goal orientation and work environment needs related to the interpretation of multi-rater feedback

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    The purpose of the present study was to gain a better understanding of how individuals process the information received in a multi-rater feedback format. The goal orientation and work environment needs of the feedback recipients were assessed in order to determine whether they were more likely to attend to the ratings from one source (i.e.,manager, peers, direct reports) than another.Using Ashford and Cummings\u27 (1983) model of the feedback-seeking process asa point of departure, it was hypothesized that the needs of the feedback recipients would influence which aspects of the feedback report they would mentally process. Previousresearch demonstrated that performance goal-oriented individuals value external rewards more than individuals with a learning goal orientation (Pintrich & Garcia, 1991). Thus,individuals with a performance goal orientation were predicted to attend more to the feedback received from their manager due to the greater access to external rewards possessed by managers. Hence, the recall of information received from the manager was expected to be greater than that of other feedback sources due to the perception that the manager could better meet the needs of the feedback recipient.Subjects were 210 employees who had recently participated in a multi-rater feedback program as part of a larger organizational change initiative at a southeastern public utility. Questionnaires were completed and each participant was interviewed by the researcher approximately two months after receiving his or her multi-rater feedbackreport.VIThe results indicated that goal orientation and an individual\u27s work environment needs did not generally result in a differential processing of information from one feedback source relative to another as measured by recall. Interestingly, however,individuals with a low learning dominant goal orientation were generally more familiar with their feedback in a global sense than individuals with a high learning dominant goal orientation. Also interesting was the finding that feedback recipients differentiate between the usefulness of the information received from a particular source depending on the purpose for the information. For example, when asked which source provided the most useful information about their strengths, a majority of individuals chose peers or direct reports. The opposite was found when individuals were asked to identify the source that provided them with the most useful information about their developmental needs. Upon further exploration of this phenomenon, it was discovered that those employees who chose peers or direct reports as providing the most useful information about their developmental needs also indicated wanting a significantly greater amount of recognition from their manager than they were currently experiencing.Although the relationship between learning goal orientation and the ability to recall feedback on the multi-rater feedback report was found to be negative, individuals with a higher learning goal orientation were more likely to actively participate in a developmental activity based on the information received in the feedback report. Similar Results were found for individuals with a higher need for professional development.These findings indicated that, although high learning-oriented individuals were less likely to process all of the information presented in the report, they may be more likely toVllactually choose a particular dimension for development and follow through with the developmental activity.In summary, an individual\u27s goal orientation did not engender a differential processing of information from one feedback source more than another source as predicted. Surprisingly, individuals with a low learning goal orientation were generally more familiar with their feedback in a global sense than individuals with a high learning goal orientation; however, high learning goal-oriented individuals were more likely to participate in developmental activities based on the feedback that they received

    Environmental and Forest Planning in Italy: Conflicts and Opportunities

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    The necessity of a more sustainable use of lands and environmental resources in general, throughout specific programming and management tools at different scale levels is nowadays widely shared. Forests and woodlands are a key asset of the environment and the traditional and current landscapes. With regards to the state of art of forest planning and management tools in Italy, in this short paper, after a synthetic analysis of the tools currently adopted at different levels, some critical aspects of the relationships of forest planning instruments with other planning tools involved in environmental management (landscape plan, energy plans, basin plans) are investigated, enlightening contrasts and communication conflicts. Solving such problems could enhance the effectiveness of planning

    POPOLAMENTI MARGINALI DI FAGGIO E CAMBIAMENTI CLIMATICI IN SICILIA: CRITICITÀ ED EFFETTI DELL’APPLICAZIONE DI PRATICHE SELVICOLTURALI TRADIZIONALI NON-SOSTENIBILI AL VARIARE DELLE CONDIZIONI MICRO-STAZIONALI

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    Il faggio (Fagus sylvatica) è una tipica specie medio-Europea; in Sicilia si rinvengono i boschi di faggio più meridionali d’Europa. La marginalità ecologica di questi boschi è particolarmente evidente nei pattern frammentati e isolati di questi soprassuoli, in prossimità del limite della vegetazione arborea e/o localizzati nelle condizioni topografiche meno favorevoli. Nel presente lavoro si mettono a confronto i parametri dendrometricostrutturali e lo stato di salute delle piante in soprassuoli delle Madonie, confrontando cedui di faggio recentemente sottoposti a pratiche di taglio e aree di controllo non trattate da tempo. Inoltre, questi aspetti sono stati messi in relazione con il gradiente topografico locale ed alla frammentazione della copertura.Sulla base delle condizioni topografiche marginali (crinali, versanti) e della frammentazione della copertura (alberi al margine/radura), i risultati mostrano chiaramente una forte riduzione dello stato di salute delle piante (maggiori danni alla corteccia e alla chioma, una percentuale più alta di alberi morti, una minore densità di rinnovazione) correlate all’intervento di taglio del ceduo. Il chiaro deperimento delle piante può determinare in futuro una minaccia crescente per queste faggete multi-marginali (per latitudine, topografia e frammentazione della copertura). Inoltre, i risultati ottenuti fanno ipotizzare che, anche se l’effetto degli interventi selvicolturali è evidente nei due gruppi a confronto (aree tagliate e aree controllo), la riduzione dello stato di salute di queste piante sia ulteriormente accelerata dagli effetti che il cambiamento climatico generale sta determinando in queste condizioni stazionali di marginalità ecologica. Il ridotto stato di salute delle piante anche nelle aree di controllo avvalora questa ipotesi.Marginal fragmented beech stands and climate change in Sicily: effects of non-sustainable traditional silviculture practices in relation to micro-topographic gradient In Sicily where the southernmost beech forests of Europe are located, beech stands show peculiar ecological, characters. The ecological marginality of these forests is particularly evident in the fragmented and isolated beech stands, near the timberline and/or located on less favourable topographic conditions. In this study we analyzed stand-structural parameters and tree health comparing recently coppice felled beech stands and control plots. Additionally, these aspects have been related also to the local topographic gradient and the cover fragmentation. Results clearly show a pronounced tree health reduction (more crown and bark damages, higher percentage of dead trees, lower seedling density) related to cut coppice, as far as to marginal topographic condition (on ridges and slopes) and stand-cover fragmentation (in clearing/border trees). The clear decreased tree health may lays an increasing future threat for these multi-marginal (for latitude, topography and cover fragmentation) beech stands. In addition, our results could also support the hypothesis that, although the silviculture effects originated by the human actions is quite evident in the two compared groups (coppice-cut and control), hastening the tree health reduction, a general climate change effect is going on these marginal beech stands. The reduced tree health status also in control plots seems to show this way

    Effects of traditional coppice practices and microsite conditions on tree health in a European beech forest at its southernmost range

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    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 vs. interior trees). Our results clearly showed a correlation between declining tree health (crown and bark damage, higher percentage of dead trees and lower seedling density) and recent coppice-cuts, poor (marginal) site quality (on ridges and slopes) and reduced canopy cover (in clearing/border trees). The decrease of tree health indicate an increasing threat to the long-term viability of beech stands facing multiple environmental stress factors (such as those related to southern latitude and topographic position). Declining tree health in the control plots also supports this hypothesis. We concluded that traditional forest management practices, such as coppice-cuts applied regardless to the specific microenvironmental conditions, may pose a risk to beech forest health at the southernmost edge of the species’ range

    Popolamenti marginali di faggio e cambiamenti climatici: criticità dell’applicazione di pratiche colturali classici in ambiente mediterraneo (Sicilia)

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    Il faggio (Fagus sylvatica) è tra le specie forestali più importanti d’Europa per distribuzione, selvicoltura, rilevanza paesaggistica. Il faggio in Sicilia raggiunge il limite meridionale del proprio areale, nonché le quote altitudinali più elevate in Europa (timberline intorno a 2000 s.l.m.), localizzandosi sui Monti Nebrodi, Madonie ed Etna. La maggior parte di questi soprassuoli è stata tradizionalmente governata a ceduo semplice matricinato, seppur raramente all’interno di un quadro di interventi pianificati di lungo periodo, e molti popolamenti recentemente hanno subito primi interventi di avviamento alla conversione a fustaia. L’assetto attuale di questi soprassuoli è tuttavia destinato a cambiare nell’immediato futuro non solo per l’opera dell’uomo, ma soprattutto in vista dei probabili scenari del cambiamento climatico, particolarmente severi nelle loro previsioni per questi contesti di margine. Il presente lavoro è volto all’individuazione dei principali elementi di vulnerabilità, prendendo in esame alcuni soprassuoli particolarmente rappresentativi dei Monti Madonie, poiché essi presentano sintomi di sofferenza e segni di disseccamento e moria, probabilmente imputabili, oltre che ai mutamenti climatici in atto, a interventi di taglio di diversa entità, dalla dubbia finalità. Oltre ai consueti rilievi selvicolturali e dendro-auxometrici, sono state condotte indagini accurate sulla struttura dei popolamenti, tramite 4 aree di saggio permanenti in corrispondenza di aree sottoposte a taglio in epoche diverse e per 2 di queste sono state identificate delle aree testimone. Una parte fondamentale dello studio ha riguardato il rilievo dell’entità dei danni osservati a carico delle chiome e delle scottature dei fusti e delle principali branche delle singole ceppaie. L’analisi della struttura è stata condotta tramite l’applicazione di numerosi indici (Clark-Evans, Winkelmass, Shannon, Latham) nonché osservazioni scaturite dalla rappresentazione spaziale delle coperture analizzate, al fine di valutare i danni riscontrati rispetto alle mutate condizioni di illuminazione delle chiome delle singole ceppaie, generate dagli interventi di taglio. L’analisi comparativa dei risultati mostra chiaramente come gli interventi intensi di diradamento recentemente eseguiti abbiano generato una elevata incidenza di danni diffusi sulle diverse parti del soprassuolo, con effetti anche estremi di moria delle ceppaie. L’effetto negativo delle eccessive scoperture causato dagli interventi di taglio si è manifestato con severità sulle piante di faggio localizzate in prossimità delle radure e delle interruzioni della copertura. In conclusione vengono messe in evidenza le criticità delle pratiche selvicolturali applicate ai soprassuoli di faggio in tali contesti limite e, conseguentemente, l’accelerazione impressa ad una probabile dinamica in atto sotto gli effetti dei noti cambiamenti climatici

    Approccio alla caratterizzazione di un lembo di bosco vetusto: il caso di Monte Egitto

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    An integrated approach to characterize an old growth forest patch; the Monte Egitto case study Old growth forests, i.e. forests which have achieved a remarkable age without or with a very limited disturbance, are nowadays subject of detailed studies in order to understand their characters and capacity of ecosystems services providing. In Sicily only few wooded areas are classified as old growth forest, following the heavy land use change toward agriculture during the centuries. This paper reports the results of a study carried out to characterize the vegetation of a little crater on the Mount Etna, where a residual open wood of Quercus congesta (an endemic oak of Southern Italy) survived the year 1651 lava flows surrounding the crater. About 35 years ago inside the crater some areas were planted with Calabrian Black Pine. As a consequence today there is a remarkable competition between trees of the two species. An integrated approach monitoring was adopted, taking into account both trees and understory (herbs, shrubs and tree regeneration) characters as well as bird fauna, in order to describe the current situation and monitor the effect of pine plantation thinning aimed at favouring oak regeneration and reducing pine-oak competition

    I RIMBOSCHIMENTI DI CEDRO DELL’ATLANTE [Cedrus atlantica (ENDL.) MANETTI EX CARRIÈRE] IN SICILIA

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    Il cedro dell’Atlante [Cedrus atlantica (ENDL.) MANETTI EX CARRIÈRE], introdotto in Europa come pianta ornamentale, ha trovato largo impiego nei rimboschimenti in Francia, Spagna e Portogallo, mentre in Italia la sua diffusione è stata più recente e a oggi interessa oltre 2600 ettari, dimostrando ottime potenzialità, senza comportamenti invasivi. In Sicilia, benché poco diffusa, la specie sembra avere potenzialità di adattamento e di produzione interessanti. Il presente lavoro prende in considerazione 7 popolamenti di cedro dell'Atlante dislocati in ambiti diversi rappresentativi delle condizioni ambientali locali, compatibili con le esigenze ecologiche della specie, tra questi un rimboschimento sottoposto a interventi di diradamento. Sono state esaminate le caratteristiche dendro-auxometriche dei popolamenti al fine di valutarne le potenzialità produttive. I risultati mostrano che i popolamenti in esame hanno ottima capacità di affermazione, seguono gli sviluppi tipici della specie e hanno possibilità di produzione elevate, pari a quelle riscontrate in letteratura per le piantagioni realizzate in Francia. Inoltre si nota l'interessante ruolo paesaggistico, sia pur considerandone la natura alloctona, che questi popolamenti possono svolgere in ambiti di non facile colonizzazione per specie arboree. Infine si suggeriscono alcuni indirizzi di gestione volti ad assicurarne la migliore affermazione e la possibilità di rinnovazione, sia pur su scala locale. Atlas cedar (ENDL.) MANETTI EX CARRIÈRE] plantations in Sicily Atlas Cedar has been widely diffused in reforestation in Europe, particularly in France. In Italy, the Atlas Cedar cover about 2600 ha. This paper examines 7 cedar plantations in Sicily, in the various typical condition of the island, evaluating their dendrometric characters in order to estimate productivity and growth capacity. The results show that this specie is both highly suitable for wood production, and has a landscape restoration role in difficult ecological conditions such as the Mediterranean mountain environment is. The stand production is comparable with the better results reported for the French plantations. Some cultivation advices in order to better manage these stands and locally assure natural regeneration are also addressed

    3.Storia, caratteri ed evoluzione dei boschi e dei rimboschimenti di Monte Morello e della Calvana _ 4. La vegetazione di Monte Morello e della Calvana

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    il lavoro divulgativo espone un'attenta analisi dei caratteri geologici, pedologici, vegetazionale dei due rilievi della Toscana settentrionale, con particolare riferimento ai rimboschimenti storicamente realizzati e alla flora endemica. Il libro è ricco di schemi funzionali, illustrazioni didattiche e di una ricca raccolta fotografica
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