Search results for " Legno"
showing 10 items of 90 documents
La fabbrica del cielo. Il soffitto della Cappella Palatina e il tetto della Cattedrale tra tecnica e arte
2020
Prodotto di successive demolizioni e ricostruzioni, la Cattedrale di Palermo, giunta a noi nell’attuale configurazione, ha subito numerose modificazioni la cui più nota è quella tardo settecentesca. Il Tempio primigenio risale al periodo successivo l'Editto di Costantino. Ricostruito al tempo di Gregorio Magno e convertito al culto islamico dopo la conquista araba sarà restaurato al culto cristiano sotto il regno normanno degli Altavilla e successivamente riedificato. La cattedrale normanna era coperta da un tetto ligneo composto da 19 incavallature riccamente decorate poggiate su mensole ed attraversato da una passerella centrale. Dalla configurazione normanna ad oggi la Cattedrale ha subi…
La carpenteria lignea della piramide di copertura della Porta Nuova a Palermo
2009
Strategies to Mitigate the Effects of Soil Physical Disturbances Caused by Forest Machinery: a Comprehensive Review
2022
Abstract Purpose of Review Ground-based mechanized forest operations can cause severe soil disturbances that are often long lasting and detrimental to the health of forested ecosystems. To reduce these soil disturbances, focus is being increasingly directed at identifying and using appropriate mitigation techniques. This systematic review considered 104 scientific articles and reported the main findings according to four core themes: terrain-related factors, operational planning, machine modifications, and types of amendments used to mitigate machine-induced soil impacts. Recent Findings For terrain-related factors, most severe disturbances occur on machine operating trails exceeding 20% sl…
Determining exhaust fumes exposure in chainsaw operations
2016
Abstract The objective of this study was to investigate the inhalation exposure of forest operators to polycyclic aromatic hydrocarbons (PAHs) and BTEX (benzene, toluene, ethylbenzene and total xylenes) contained in the exhaust fumes released from chainsaws and to suggest possible countermeasures. The study was carried out in four silvicultural treatments (coppice clearcut, conifer thinning, conifer pruning, and sanitary cut), using three types of chainsaw fuel (normal two-stroke petrol mix and two alkylate fuels). Eighty personal air samples were collected; IOM samplers combined with Amberlite XAD-2 sorbent tubes were used for collecting PAHs and Radiello® samplers were used for BTEX. Resu…
Impacts of wood extraction on soil: assessing rutting and soil compaction caused by skidding and forwarding by means of traditional and innovative me…
2021
AbstractIntensive forestry operations may cause soil compaction, plastic soil disturbances and rutting, which are responsible for undesirable effects on soils, vegetation and water bodies. Despite the numerous studies aimed to identify the main factors affecting soil damages, it still remains unclear whether wood extraction methods and driving direction (uphill or downhill) may affect the impacts of forest machines. This research analyses soil compaction and soil penetration resistance as well as rutting from forwarding and skidding using the same farm tractor in up- and downhill wood extraction. Rutting was estimated by 3D soil reconstruction derived by portable laser scanning (PLS) and cl…
Can the certification of cork management agroforestry system in Sicily help to relaunch its future management?
2019
The economic importance of cork oak forests is mainly attributable to the role of provisioning non-timber forest products. The history of human management of these cork oaks stands make them a perfect example of agroforestry system, which surface is totally included in the Mediterranean-climate zones with more than 2.3 million hectares. In Sicily, the surface covered by cork forests amounts to about 15,000 ha but the most of this area is not affected by cultural practices. The cultural abandonment of many cork oak stands threatens their survival because of the close link between the conservation of cork stands and its use for productive purposes. The abandonment reasons are related to poor …
Environmental performance of wood pellets' production through life cycle analysis
2016
Abstract Forests play a key role as the source of an essential renewable material and/or fuel: wood. The aim of this study was to evaluate the environmental impacts related to high-quality pellet production for domestic heating following the LCA (life cycle assessment) methodology and considering a cradle-to-gate perspective in the Tuscany region. This is representative and interesting for Italian pellet factories and for similar factories located in Central Europe, considering the Italian contribution to the production capacity of that area. All of the activities involved, from wood extraction in no-industrial forests to packed pellet production, ready for delivery to final users, were tak…
I soffitti lignei dipinti e le strutture di copertura nell'architettura religiosa della Sicilia barocca. Conoscenza e diagnosi per il progetto di res…
2009
Wooden ceilings characterize many baroque churches in Sicily and they have a particular meaning in the spatial conception of the architecture because of the false dome prospective painted on. For such a reason they are able to dominate the baroque architectural spatiality being a planar surface. Often forgotten and difficult to reach, the wooden painted ceilings represent an meaningful testimony of history and art but they are know asking for a conservation and maintenance attitude to start. The essay explain a method to design a conservation project without scaffolding and presents the software processing phases to develop in order to point out the degradation conditions through thermograp…
The paradox of the alien plant Leucaena leucocephala subsp. glabrata (Rose) S. Zárate in Sicily: another threat for the native flora or a valuable re…
2020
With this contribution, an updated picture of the rapid expansion of Leucaena leucocephala subsp. glabrata in Sicily is provided. On the one hand, this is a quite worrying sign, as this woody species figures among the world’s worst invasive alien species. On the other hand, the species shows interesting potential for production purposes (for wood, biomass and for feeding livestock), also considering its nitrogen fixation ability. Consequently, the two opposite options to cope with this species, i.e. cultivation and control/eradication, should accurately take into account the possible uses as well as its invasive behaviou.
La Propagazione delle piante arboree da frutto
2019
Il Capitolo tratta delle problematiche e delle tecniche di propagazione delle piante arboree da frutto