Search results for "Quercus"

Dendro-archaeological contribution to the history of forest exploitation. The case of the Gallo-Roman settlement of Odenburg (Alsace, France) between…

2010

Dendro-archaeological contribution to the history of forest exploitation: a case of the Gallo-Roman settlement of Oedenburg (Alsace, France) between …

2011

International audience

Biotopu apsaimniekošanas ietekme uz veģetāciju un ozolu atjaunošanos dabas liegumā "Paņemūnes meži"

2015

DL „Paņemūnes meži” tika veikta apsaimniekošana – izcērtot 2.stāvā un paaugā esošās egles. Eksperimentālie meža biotopu apsaimniekošanas darbi tika veikti LIFE+ projekta „Natura 2000 teritoriju nacionālā aizsardzības un apsaimniekošanas programma” ietvaros. Izvirzītas hipotēzes:1) pēc apsaimniekošanas darbiem zemsedzē palielināsies ozolu sējeņu skaitas un nemorālo augu sugu segumas;2) ilgtermiņā uzlabosies jau esošo ozolu augšana un attīstība. Pirmajā gadā pēc apsaimniekošanas ozolu sējeņu skaits nepalielinājās. Biotopā parādījās viena nemorālā suga, kā arī 26 jaunas augu sugas, kas varētu nomākt ozolu sējeņus un nemorālo floru, jo tām lielākoties raksturīga strauja izplatīšanās.

Izmaiņas Quercus robur pieauguma dinamikā pēc atēnošanas mistraudzēs

2021

Maģistra darbs „Izmaiņas Quercus robur pieauguma dinamikā pēc atēnošanas mistraudzēs” izstrādāts Latvijas Universitātes Botānikas un ekoloģijas katedrā, laika posmā no 2019. gada novembra līdz 2021. gada maijam. Boreālo-nemorālo mežu pārejas zonā tiek praktizēta ozolu atēnošana, kas izpaužas kā selektīva citu koku sugu vai krūmu izciršana, kuras mērķis ir uzlabot gaismas apstākļus mistraudzēs, lai veicinātu ozolu ilgtspējīgu augšanu un atjaunošanos. Intensīva atēnošana var izmainīt audzē pastāvošo mikroklimatu, kas var ietekmēt koku jutību pret apkārtējiem vides un klimatiskajiem apstākļiem, dažādi ietekmējot koku tālāko augšanu. Darba mērķis ir noskaidrot, kā egļu izciršana mistraudzēs atē…

Free and bound hydroxyl and carboxyl groups in the cutin of Quercus suber leaves

1984

Abstract The number of free and bound hydroxyl and carboxyl groups of the cutin of Quercus suber leaves was investigated by the lithium borohydride hydrogenolysis of mesyl-cutin compared with the lithium borohydride hydrogenolysis of untreated cutin. Fifty per cent of the vic -diol groups of the trihydroxy C 18 acid component and twenty five per cent of the secondary hydroxyl groups of the dihydroxy C 16 acid component are free. The rest of the secondary and all of the primary hydroxyl groups are esterified; all carboxyl groups are esterified.

Holocene vegetation and fire dynamics in the supra-mediterranean belt of the Nebrodi Mountains (Sicily, Italy)

2012

High-resolution pollen, macrofossil and charcoal data, combined with accelerator mass spectrometry 14C dating and multivariate analysis, were used to reconstruct Holocene vegetation and fire dynamics at Urio Quattrocchi, a small lake in the supra-mediterranean belt in the Nebrodi Mountains of Sicily (Italy). The data suggest that after 10 000 cal a BP increasing moisture availability supported closed forests with deciduous (Quercus cerris, Fagus sylvatica and Fraxinus spp.) and evergreen (Quercus ilex) species. Species-rich closed forest persisted until 6850 cal a BP, when Neolithic activities caused a forest decline and affected plant diversity. Secondary forest with abundant Ilex aquifoli…

Structural studies of the hemicellulose A from the cork of Quercus suber

1987

Saproxylic beetle assemblages in the Mediterranean region:Impact of forest management on richness and structure

2010

Forests cover almost 30% of the Mediterranean region today, yet forest management activities have influenced structure and composition of both natural and planted forests. To date no study has been conducted to evaluate the impact of forest management on saproxylic beetle assemblages, although it is known that the Mediterranean is a biodiversity hotspot with a long-lasting human pressure on natural habitats. We provide an overview of saproxylic beetle assemblages of three forest types (mature Pinus halepensis forests, mature Pinus brutia forests, young Quercus calliprinos forests) in the East Mediterranean region using a one-year sample from 12 forest plots located in the north of Israel. T…

STUDIO PROPEDEUTICO PER LA REDAZIONE DI UN PIANO DI GESTIONE FORESTALE DEL BOSCO TARDARA, SUGHERETA PURA DEL COMUNE DI TUSA (MESSINA)

2019

La Sicilia è la seconda regione d’Italia per estensione delle formazioni naturali a Quercus suber (L.).Sugherete più o meno degradate sono presenti in tutte le province, il cui stato qualitativo oggi risulta carente a causa dei frequenti incendi, pascolo eccessivo e mancanza di adeguate cure colturali, ma certamente tra tutte le cause la principale è l’assenza di pianificazione. Da questa premessa affiora la necessità di conoscere e governare in modo congruo la superficie boscata siciliana attraverso la redazione di Piani di Gestione Forestale, mirando al ripristino dell’efficienza, della funzionalità e, in particolar modo, della produzione sostenibile dei boschi a sughera. Con il presente …

Site quality evaluation by classification tree: an application to cork quality in Sardinia

2005

Cork harvesting and stopper production represent a major forest industry in Sardinia (Italy). The target of the present investigation was to evaluate the ‘‘classification tree’’ as a tool to discover possible relationships between microsite characteristics and cork quality. Seven main cork oak (Quercus suber) producing areas have been identified in Sardinia, for a total of more than 122,000 ha. Sixty-three sample trees, distributed among different geographical locations and microsite conditions, were selected. A soil profile near each sample tree was described, soil samples were collected and analysed. After debarking, cork quality of each sample tree was graded by an independent panel of e…