Search results for "Quercus"

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 …

La suberaie de la Mâamora au Maroc en danger

2013

Aportaciones a la corología del género Quercus en el Sistema Ibérico meridional

2012

Se aportan citas de varios taxones del género Quercus poco conocidos o novedosos en el extremo meridional del Sistema Ibérico.SUMMARY: New records of several rare taxa of the genus Quercus found in the southern extreme of the Iberian Mountains are here reported.

Foreed flushing of branch segments as a method for obtaining reactive explants of mature Quercus robur trees for micropropagation

1994

The aim of this study was to micropropagate mature Quercus robur L. trees when material retaining physiologically juvenile characteristics (stump sprouts, epicormic shoots) is not available. Branch segments from 70–300 year-old trees were force-flushed and the flushed, partially rejuvenated or reinvigorated shoots were used as a source of explants for establishment of cultures. In vitro establishment and multiplication was achieved with seven of the eight selected trees. The proliferation capacity of cultures of vertically placed explants declined after several subcultures, but efficient shoot multiplication was achieved by culturing decapitated shoots placed horizontally on GD medium suppl…

Home advantage? Decomposition across the freshwater-estuarine transition zone varies with litter origin and local salinity

2015

Expected increases in the frequency and intensity of storm surges and river flooding may greatly affect the relative salinity of estuarine environments over the coming decades. In this experiment we used detritus from three contrasting environments (marine Fucus vesiculosus; estuarine Spartina anglica; terrestrial Quercus robur) to test the prediction that the decomposition of the different types of litter would be highest in the environment with which they are associated. Patterns of decomposition broadly fitted our prediction: Quercus detritus decomposed more rapidly in freshwater compared with saline conditions while Fucus showed the opposite trend; Spartina showed an intermediate respon…

1200-yr high-resolution terrestrial climate archive from the middle of the Mediterranean: The sedimentary record from Lake “Specchio di Venere” on Pa…

2011

The special location of Lake "Specchio di Venere" on Pantelleria Island in the Sicily Channel (Mediterranean Sea) between Tunisia and Sicily offers a unique terrestrial archive recording atmospheric changes, which are otherwise difficult to decipher in the marine records from this area. The lake is an endorheic saline basin with a maximum depth of 12.5 m. As the water input depends on rainfall, precipitation variations influence changes of the lake's water chemistry. In summer 2008, Lake Venere was cored with a modified Livingstone corer revealing a composite sedimentary sequence of 10.29 m length. Two radiocarbon dates form a preliminary age model indicating a very high sedimentation rate …

INFLUENZA DEL CLIMA SULLA CRESCITA DEL SUGHERO IN SOPRASSUOLI PRODUTTIVI SICILIANI.

2009

Abstract: Cork oak (Quercus suber L.) is usually dominant in silvopastoral systems in many areas of Sicily, where the trees are debarked periodically for cork production. In spite of the importance of cork and cork oak stands in Sicilian forests and the potential economic scenarios, few research works have been carried out on these systems. Given the importance of cork thickness in cork quality evaluation, the main objective of this work is to study cork growth in cork oak productive stands spread on the north (Nebrodi Mountains) and south-east (Iblei Mountains) of Sicily. Image analysis techniques were used on cork surfaces of transverse sections of planks to measure cork rings. Dendrochro…

The cork oak forests management in Sicily: current situation and potentiality

2017

The economic importance of cork forests is mainly attributable to the role of provisioning non-timber forest products that they have played and still play in the Mediterranean region. In Sicily, according to the latest regional forest inventory (IFRS, 2010), the surface covered by cork forests amounts to 14,732 ha; the 52.4% of this area is not affected by cultural practices, while in the 41.3% of cases productive cultural practices are adopted. In fact, the prevailing silvicultural system type is the peculiar one aimed at the cork production. The cultural abandonment of many cork oak stands threatens their survival because of the close link between the conservation of cork stands and its u…

Studies on the Quercus hybrids in Sicily: leaf micromorphology and xylem structure in Quercus × fontanesii Guss.

2000

In order to find new suitable characters in the taxonomic delimitation of the genus Quercus, whose hardness is well known, Quercus x fontanesii, endemic to Sicily, has been studied in comparison with its parents, i.e. Q. gussonei, wich is close to Q. cerris, and Q. suber. These taxa are here delimited as far as taxonomy, ecology, and Sicilian distribution are concerned. Furthermore, the results of SEM microstructure analysis of leaves and xylem anatomy are illustrated and commented. The analysis of the leaf microstructures shows that there is a remarkable similarity between the stomata and stellata trichomes of Q. x fontanesii and both the parental species, as the trichome rays are numerica…

Primi dati sugli alberi monumentali di Pantelleria

2016

Poche o nulla sono le informazioni sugli alberi monumentali delle piccole isole che circondano la Sicilia. Ciò è dovuto innanzitutto alla rarità di alberi definibili monumentali, le piccole isole hanno subito infatti una trasformazione ancora più profonda della Sicilia, ma anche ad un difetto di conoscenza. Il nostro vuole essere un primo contributo alla conoscenza degli alberi monumentali nell’isola di Pantelleria. Gli alberi censiti appartengono a due specie, il pino marittimo (Pinus pinaster subsp. hamiltonii) e il leccio (Quercus ilex). In realtà nel caso del pino marittimo possiamo parlare di un “popolamento monumentale” corrispondente alla pineta a pino marittimo presso la località Mo…