Wood Density and Ring Width in Quercus rotundifolia Trees in Southern Portugal

Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both sites. Cambial age was the main source of variation for ring width and wood density, while between-tree effects accounted for a considerable proportion of wood density variation. The results are an important contribution for the species valorisation aiming at high-value wood products, also adding knowledge on the species growth of interest for tree selection and sustainable management.

Quercus rotundifolia Bark as a Source of Polar Extracts: Structural and Chemical Characterization

Quercus rotundifolia bark was studied regarding anatomical, chemical, and antioxidant properties from trees in two sites in southern Portugal and are here reported for the first time. The general structure and anatomy of Q. rotundifolia bark showed a rhytidome with sequential undulated and anastomosed periderms with a small proportion of cork, while the phloem included broad rays with strong cell sclerification, groups of sclereids with embed large prismatic crystals, and abundant druses in parenchyma cells. The mean chemical composition was 15.5% ash, 1.6% dichloromethane extractives, 6.4% ethanol and 9.3% water extractives, 3.0% suberin, 30.5% total lignin, and 33.8% carbohydrates. Carbohydrates included mainly glucose (50.7% of total monomers) and xylose (23.8%), with uronic (3.0%) and acetic acids (1.0%). Suberin was mainly composed of ω-hydroxyacids (48.0% of all compounds) and α,ω-diacids (19.5%). The main compounds found in the lipophilic extracts were triterpenes (43.6%–56.2% of all compounds) and alkanoic acids (32.7%–41.7%). Phenolic content was high especially in the ethanol extracts, ranging from 219.5–572.9 mg GAE/g extract and comprising 162.5–247.5 CE/g extract of flavonoids and 41.2–294.1 CE/g extract of condensed tannins. The extracts revealed very good antioxidant properties with IC50 values of 4.4 µg ethanol extract/mL and 4.7 µg water extract/mL. Similar anatomical, chemical, and antioxidant characteristics were found in the bark from both sites. The high phenolic content and excellent antioxidant characteristics of polar extracts showed holm oak barks to be a promising natural source of antioxidants with possible use in industry and pharmaceutical/medical areas.

Quercus rotundifolia Lam. Woodlands of the Southwestern Iberian Peninsula

The holm oak woodlands as ecotonic phytocoenoses occur under different ecological conditions, and frequently representing the climax of edaphoxerophilous series of crests and siliceous rocky areas. In this paper we study the floristic, ecological, and biogeographical differences of the edaphoxerophilous holm oak woodlands of the southwestern Iberian Peninsula, included in the Querco rotundifoliae-Oleenion sylvestris suballiance. Our phytosociological (Braun–Blanquet methodology) and numerical analysis (hierarchical cluster analysis) of three formerly described association and our own samples lead us to propose a new association: Ulici argentei-Quercetum rotundifoliae, growing mostly on semihyperoceanic Monchique Sierran Biogeographic District, on rocky slopes and outcrops derived from schists and greywackes. Moreover, we present an overview of ecological features and the diversity of plant communities occurring in the serial dynamic of the thermophile holm oak woodlands of the southwest of the Iberian Peninsula.

Description of Marolia alicantina sp. nov. (Coleoptera: Melandryidae) from Spain and new distribution records of Marolia species

Marolia alicantina sp. nov. (Coleoptera: Melandryidae) from eastern Spain is described and illustrated. All specimens were collected using window traps on Quercus rotundifolia Lamarck, 1785 (Fagaceae) in the Carrascar de la Font Roja Natural Park (Alicante, Spain). M. alicantina sp. nov. is the only European Marolia having erect setae on the elytra and pronotum. M. alicantina resembles M. grandis Peyerimhoff, 1971 from north Africa, from which it can distinguished by the denser punctuation of the pronotum, shape of the base of the pronotum and shape of the aedeagus. Furthermore, unpublished records for other Marolia species are presented in this paper; in particular M. purkynei Mařan, 1933 is recorded for the first time in Croatia and Greece. The authors had the chance to study six specimens, subsequently labelled as syntypes, of the M. purkynei type series. The location of the remaining possible syntype remains unknown.

Morphology and structure of acorn starches isolated by enzymatic and alkaline methods

Morphology and structure of starch from fruits of two acorns species, Quercus rotundifolia Lam. (QR) and Quercus suber Lam. (QS), isolated by enzymatic (ENZ) and alkaline (A3S) methods were studied. Acorn starches granules presented a round and oval shape, consisting of medium/small granules, with a mean granule size ranging between 9 and 13 µm. Isolated acorn starches appear as light grayish-brown in naked eye, with high values of L* for starches isolated by the ENZ method, and QR starches were duller than QS. No differences were observed for all the samples in FTIR spectra results. Acorn starches showed a C-type pattern, with a relative crystallinity between 43.1 and 46.6%. The 13C CP/MAS NMR spectra are different for the used isolation methods but are similar for both acorn species. However, acorn-isolated starches presented a predominant A-type allomorph packing type, and the A3S starches showed a higher degree of crystalline material. Those differences in the structure of acorn starches would be helpful to better understand the relationships among structure and functional properties for a possible potential industrial application of chestnut starches.

Variability in subcutaneous fat composition of Iberian pigs reared in free-range conditions in the southwest of the Iberian Peninsula

A total of 80 free-range Iberian pigs reared with acorns and grass in eight different free-range systems (n = 10) in the southwest of the Iberian Peninsula were used to determine the relationship between fatty acid, tocopherol, and neophytadiene subcutaneous fat composition. The pigs were fed extensively for 79.1 ± 9.5 d from 110.9 ± 11.9 kg live weight at the beginning of the final fattening phase to 175.0 ± 15.9 kg slaughtered weight. Quercus suber and Quercus rotundifolia acorns were characterised by a high content of C18:1n-9 (58.3 and 63.1%, respectively) and γ-tocopherol [43.7 and 43.0 mg kg−1 dry matter (DM), respectively], while grass exhibited a high content of C18:3n-3 (42.5%), α-tocopherol (366.5 mg kg−1 DM) and neophytadiene (136.2 relative area units). The C18:1n-9 (54.4%–57.7%) and γ-tocopherol (2.7–4.1 mg kg−1 DM) contents in subcutaneous fat from Iberian pigs differed (p < 0.001) between the free-range systems studied. Pasture intake had a significant effect (p < 0.01) on subcutaneous fat content of C18:3n-3 (0.5%–0.8%), α-tocopherol (7.8–13.1 mg kg−1 DM) and neophytadiene (2.6–6.3 relative area units). However, the results demonstrated no correlations between accumulated levels of these compounds throughout the free-range period. In conclusion, the absence of correlations corroborated the heterogeneity of extensive rearing systems, with variations between years and geographical areas where the Iberian pigs were reared.

Flora y vegetación de la Sierra de Alcaparaín (Málaga, España)

Español. El objetivo de este trabajo es realizar un catálogo de la flora, de las comunidades vegetales y el estudio del dinamismo sucesional y del paisaje vegetal de la Sierra de Alcaparaín, que forma parte de una Zona de Especial Conservación (ZEC) situada en la provincia de Málaga (Andalucía, España). El macrobioclima es de tipo mediterráneo con termotipos termo y mesomediterráneo y ombrotipos seco y subhúmedo. El área de estudio está compuesta geológicamente por materiales calizo-dolomíticos, silíceos y peridotíticos, con elevadas pendientes y altitudes entre 400 y 1295 m. y se encuentra en la provincia fitogeográfica Bética (región Mediterránea), con los sectores Rondeño (zonas calizo-dolomíticas), Malacitano-Axarquiense (zonas silíceas) y Bermejense (zonas peridotíticas). El catálogo florístico se compone de 467 taxones, destacando el endemismo local Armeria grajoana y Centaurea carratracensis (VU), endémica del subsector Carratracense (sector Bermejense). Otros taxones interesantes son Linaria clementei (VU), Platycapnos tenuiloba subsp. parallela (VU), Polygala webbiana (única localidad europea), Salvia candelabrum (VU) y Sarcocapnos baetica subsp. baetica (VU). Son remarcables también un total de 7 serpentinófitos destacando Crepis bermejana, Galium boissieranum (VU) y G. viridiflorum (VU). Se han catalogado 28 comunidades y asociaciones vegetales, entre las que destacan como novedades sintaxonómicas la vegetación glerícola vivaz sobre peridotitas (Crambe filiformisCentaureetum carratracensis comb. nova et stat. nov.), los jarales silicícolas rondeños (Lavandulo stoechadisGenistetum equisetiformis ulicetosum baetici subass. nova), los pinares-sabinares mesomediterráneos (Pino halepensis-Juniperetum phoeniceae rhamnetosum myrtifoliae subass. nova) y los encinares edafoxerófilodolomitícolas (Rhamno myrtifoliae-Quercetum rotundifoliae ass. nova). El dinamismo sucesional se expresa en seis series de vegetación. Dos series climatófilas termo y mesomediterráneas de Quercus rotundifolia y de Quercus suber. Tres series edafoxerófilas: termo-mesomediterránea calcícola-dolomitícola de Pinus halepensis y Juniperus phoenicea, mesomediterránea dolomitícola de Quercus rotundifolia y serpentinícola con Juniperus oxycedrus. Existe también una serie edafohigrófila de saucedas (Salix pedicellata). En los frecuentes hábitats rupícolas se describen 3 complejos topogénicos (entre ellos uno con Saxifraga globulifera) y 2 glerícolas (uno sobre kakiritas con Linaria clementei y otro sobre serpentinas con Centaurea carratracensis). En la Sierra existen 8 grandes unidades de paisaje zonopotencial, caracterizados en gran medida por la presencia de Quercus rotundifolia y Q. suber, así como por gimnospermas como Pinus halepensis, Juniperus phoenicea y J. oxycedrus.English. The main objective of this work is to catalogue the flora and plant communities and to study the successional dynamics of the vegetation and landscape in the Alcaparain mountain range, which is part of a Special Area of Conservation (SAC) located in the province of Malaga (Andalusia, Spain). The macrobioclimate is Mediterranean with thermomediterranean and mesomediterranean thermotypes (vegetation belts) and dry and sub-humid ombrotypes. The study area is geologically composed of limestone-dolomitic materials, siliceous and ultramafic, with steep slopes and altitudes between 400 and 1295 m. and it is placed in the Betica phytogeographical province (Mediterranean region), with Rondeño sector (limestone-dolomite areas) Malacitano-Axarquiense sector (siliceous areas) and Bermejense sector (peridotite-ultramafic areas). The floristic list consists of 467 taxa, highlighting local endemism Armeria grajoana and Centaurea carratracensis (VU), this latter endemic to the Carratracense subsector (Bermejense sector). Other interesting taxa are Linaria clementei (VU), Platycapnostenuiloba subsp. parallela (VU), Polygala webbiana (unique European population), Salvia candelabrum (VU) and Sarcocapnos baetica subsp. baetica (VU). Also noteworthy are a total of 7 serpentinophytes highlighting Crepis bermejana, Galium boissieranum (VU) and G. viridiflorum (VU). 28 communities and plant associations have been catalogued, among which are new syntaxa as the perennial scree vegetation on peridotites (Crambe filiformisCentaureetum carratracensis comb. nova et stat. nov.), the silicicolous shrublands of Rondense subsector (Lavandulo stoechadis-Genistetum equisetiformis ulicetosum baetici subass. nova), the mesomediterranean pine-juniper open forest (Pino halepensis-Juniperetum phoeniceae rhamnetosum myrtifoliae subass. nova) and dolomitic edaphoxerophyllous oak shrublands (Rhamno myrtifoliae-Quercetum rotundifoliae ass. nova). The successional dynamism is expressed in six vegetation series. Two are thermo- and mesomediterranean climatophilous series of Quercus rotundifolia and Quercus suber respectively. Three are edaphoxerophyllous series: thermo-mesomediterranean calcicolous-dolomiticolous with Aleppo pine and Juniperus phoenicea, dolomiticolous mesomediterranean of Quercus rotundifolia and serpentinicolous with Juniperus oxycedrus. There is also one edaphohygrophyllous series of willow (Salix pedicellata). Vegetation of the frequent rocky and cliff habitats are described in three topogenous complexes (including one with Saxifraga globulifera) and two in screes (one on kakirite sands with Linaria clementei and another on serpentine small slopes with Centaurea carratracensis). In the Sierra there are eight large zonopotential units of landscape, mainly characterized by the presence of Quercus rotundifolia (and in a lesser extent, Q. suber) as well as gymnosperms as Aleppo pine, Juniperus phoenicea and J. oxycedrus.