Evergreen Oak Woods Research Articles

The first report of an ‘evergreen Castanopsis type’ wood (Fagaceae) for the Late Miocene–Early Pliocene of Europe (Bulgaria, Blagoevgrad Graben)

In the present article, the establishment of the species Castanopsis: C. bulgarica Mantzouka, Ivanov, and Bozukov is proposed after the study of a new fagaceous fossil wood stem discovered in 2016 from a new Late Miocene to Early Pliocene plant fossiliferous locality east of Boboshevo town, south‐west Bulgaria. A detailed palaeoxylotomical study of the fossil wood revealed characteristics of the ‘evergreen Quercus type’ (e.g. the gradual porosity of the vessels, the existence of two types of rays: uniseriate and multiseriate aggregate, the oval shape of the solitary vessels outline, the occurrence of tracheids) as well as heterocellular compound‐aggregate rays, typical for Castanopsis. Similarities and differences of the anatomical characteristics/features of the studied specimen with the descriptions of the fossil representatives of Fagaceae (Quercoxylon, Lithocarpoxylon, and Castanopsis) along with its botanical affinities are discussed. A taxonomic list of the Bulgarian fossil fagaceous record of the same age and their nearest living relatives is provided. Emended xylotomical keys with the addition of Castanopsis have been created. Moreover, the presence of evergreen Castanopsis species with heterocellular rays of two distinct sizes in the fossil record of the ‘evergreen oak woods’ is supported.

Spatial pattern of tree diversity and evenness across forest types in Majella National Park, Italy

Estimation of tree diversity at broader scale is important for conservation planning. Tree diversity should be measured and understood in terms of diversity and evenness, two integral components to describe the structure of a biological community. Variation of the tree diversity and evenness with elevation, topographic relief, aspect, terrain shape, slope, soil nutrient, solar radiation etc. are well documented. Present study explores the variation of tree diversity (measured as Shannon diversity and evenness indices) of Majella National Park, Italy with five available forest types namely evergreen oak woods, deciduous oak woods, black/aleppo pine stands, hop-hornbeam forest and beech forest, using satellite, environmental and field data. Hop-hornbeam forest was found to be most diverse and even while evergreen Oak woods was the lowest diverse and even. Diversity and evenness of forest types were concurrent to each other i.e. forest type which was more diverse was also more even. As a broad pattern, majority portion of the study area belonged to medium diversity and high evenness class. Satellite images and other GIS data proved useful tools in monitoring variation of tree diversity and evenness across various forest types. Present study findings may have implications in prioritizing conservation zones of high tree diversity at Majella.

Epiphytic bryophyte flora in dry environments from the Western Mediterranean: The special case of Sierra Alhamilla (Almería, South‐eastern Spain)

In dry Mediterranean environments, the epiphytic habitats are generally poor in bryophytes. However, Sierra Alhamilla, a mountain embedded in one of the driest areas in Europe, is an exception. It shelters an evergreen oak wood, whose richness in epiphyte bryophytes is similar to or higher than that of humid mountain ranges from the Iberian Peninsula and North Africa. The genus Orthotrichum, besides dominating the epiphyte communities on tree trunks and bases, is the most diverse group (45% of the catalogue), and comprises a bulk of species (e.g., Orthotrichum scanicum, Orthotrichum ibericum, Orthotrichum speciosum var. brevisetum) that makes this site especially original. The profiles of the recorded bryoflora (dominance of Orthotrichaceae and Pottiaceae, prevalence of cushions and short turfs and high similarity of tree base and trunk bryophyte communities) indicate an epiphytic bryoflora mainly conditioned by the dry climate. However, the species richness and the biogeographical profile (e.g., dominance of temperate element and occurrence of species that have mesic affinities), together with the altitude influence on structure and composition of bryophyte communities, suggest the existence of microclimatic factors that soften the environmental aridity. This softening effect could be more important at higher altitudes, which are floristically richer than the lower ones.

Microbial activity and quality changes during decomposition of Quercus ilex leaf litter in three Mediterranean woods

Changes in enzyme activities during litter decomposition provide diagnostic information on the dynamics of decay and functional microbial succession. Here we report a comparative study of enzyme activities involved in the breakdown of major plant components and of other key parameters (microbial respiration, fungal biomass, N, lignin and cellulose contents) in homogeneous leaf litter of Quercus ilex L. incubated in three evergreen oak woods in Southern Italy (Campania), differing for chemical and physical soil characteristics and microclimatic conditions. The results showed that the litter mass loss rates were similar in the three wood sites. Independently of the incubation sites, cellulase, xylanase and peroxydase activities showed seasonal variations with maximum and minimum levels in wet and dry periods, respectively, and this pattern closely matched microbial respiration. Activities of α- and β-amylase, instead, were high at the beginning of incubation and quickly decreased with decomposition progress because their substrate was rapidly depleted. Laccase activity, in contrast, was low at the beginning of incubation but after 6 months it increased significantly. The increase of laccase activity was correlated to an increase in fungal biomass, probably reflecting a major shift in the litter microbial community. As concerns quality changes, N and lignin content did not significantly change during decay. The cellulosic component started being degraded after about 6 months in the litter incubated in two of the three wood sites and from the start of decomposition in the third site. Apart from minor differences in the levels of certain enzyme activities, the data showed that the functional microbial succession involved in the decomposition of Q. ilex leaf litter did not change appreciably in response to differences in soil and microclimatic conditions in the incubation sites.

Adsorption of Zn(II) in aqueous solution by activated carbons prepared from evergreen oak ( Quercus rotundifolia L.)

In the present work activated carbons have been prepared from evergreen oak wood. Different samples have been prepared varying the concentration of the activating agent (H 3PO 4) and the treatment temperature. The yield of the process decreases with increasing phosphoric acid concentrations. Furthermore, high concentrations of activating agent lead to mainly mesoporous activated carbons to the detriment of the microporous texture. Treatment temperatures up to 450 ° C lead to a progressive increase of the micro- and mesopore volumes. Values of specific surface area ( S BET ) as high as 1723 m 2 g −1have been obtained using appropriate phosphoric acid concentrations and treatment temperatures. The samples prepared have been successfully used in the removal of Zn(II) from aqueous solutions. From the adsorption kinetic data it may be stated that the equilibrium time is, in all cases, below 170 h. The adsorption process as a rule becomes faster as the mesopore volume and specific surface area of the samples increase. The adsorption isotherms in liquid phase point out that the adsorption capacity ( n 0 s ) and the affinity towards the solute ( K ci ) are higher for the sample showing the most developed mesoporous texture and surface area as well.

Circulating corticosterone levels in breeding blue tits Parus caeruleus differ between island and mainland populations and between habitats

Little is known about whether adaptations to an insular life also involve adaptations in basal corticosterone levels or in the adrenocortical stress response, thus being part of a genetically based island syndrome. However, differences in corticosterone between island and mainland may also be a direct phenotypic response to differences in environmental conditions or may depend on individual characteristics of the animal such as body condition or parental investment. In this paper, we investigated whether insular (Island of Corsica) and mainland (nearby Southern France) blue tits Parus caeruleus populations differed in baseline and handling-stress induced corticosterone levels during the breeding season as a response to biological changes of insular biota. We also examined whether corticosterone levels of both mainland and insular blue tits differed between birds living in two different habitats (summergreen and evergreen oak woods) that differ in food availability and whether individual characteristics affected corticosterone levels. We found (a) differences in baseline corticosterone plasma levels between Corsica and the mainland, independent of regional differences in fat scores, (b) a regional difference in the relationship between corticosterone levels and brood size, (c) a difference in the rapidity of onset of the stress response to handling between habitats, independent of region, and (d) a negative relationship between body fat stores and baseline corticosterone levels independent of region. Reduced baseline corticosterone levels on Corsica may be a component of the insular syndrome, allowing birds to be less aggressive and to enhance parental investment despite higher breeding densities. We suggest that baseline corticosterone levels are only elevated if food availability affects directly the parents. However, when conditions deteriorate unexpectedly (as mimicked by handling stress), food allocation between parents and offspring needs to be re-adjusted in favor of the parents, possibly by increased circulating corticosterone levels. The switch to self-maintenance seems to be modified by the amount of body energy stores.

Reproductive Investment of a Lacertid Lizard in Fragmented Habitat

Abstract: We studied the effect of habitat fragmentation on female reproductive investment in a widespread lacertid lizard ( Psammodromus algirus) in a mixed‐forest archipelago of deciduous and evergreen oak woods in northern Spain. We captured gravid females in fragments (≤10 ha) and forests (≥ 200 ha) and brought them to the laboratory, where they laid their eggs. We incubated the eggs and released the first cohort of juveniles into the wild to monitor their survival. Females from fragments produced a smaller clutch mass and laid fewer eggs (relative to mean egg mass) than females of similar body size from forests. Lizards did not trade larger clutches for larger offspring, however, because females from fragments did not lay larger eggs (relative to their number) than females from forests. Among the first cohort of juveniles, larger egg mass and body size increased the probability of recapture the next year. Thus, fragmentation decreased the relative fecundity of lizards without increasing the quality of their offspring. Reduced energy availability, increased predation risk, and demographic stochasticity could decrease the fitness of lizards in fragmented habitats, which could contribute to the regional scarcity of this species in agricultural areas sprinkled with small patches of otherwise suitable forest. Our results show that predictable reduction of reproductive output with decreasing size of habitat patches can be added to the already known processes that cause inverse density dependence at low population numbers.

The use of distance sampling and mark‐resight to estimate the local density of wildlife populations

AbstractWe used distance sampling (line transects) and mark‐resight to estimate habitat and local area (area size, range: 3.9–44.5 ha) population density of ungulates. The distance sampling study was performed on fallow deer (Dama dama), roe deer (Capreolus capreolus) and wild boar (Sus scrofa) in a mediterranean forest. The mark‐resight study was performed on a roe deer population in a hilly area of the Apennines. The first study allowed us to estimate the animal density into four different habitats (deciduous oak wood, evergreen oak wood, maquis and open areas with domestic‐pine woods). The between habitat differences of population density are large for the three species: fallow deer are more abundant in the open areas (22.22 heads/km2, c.i. 12.42–39.74), roe deer in the deciduous oak wood (14.50 heads/km2, c.i. 7.01–30.10) and wild boar in both the open areas (11.29 heads/km2, c.i. 4.86–26.20) and evergreen oak wood (10.42 heads/km2, c.i. 6.78–16.02). The roe deer population in the Apennines is characterized by large between‐zone variations of population density (range: 1997: 13.25–131.31, 1998: 29.06–78.01, 1999: 10.67–88.58). Moreover, trends of local zones may be quite different with respect to the average trend of a wider study area, suggesting a well‐defined short‐scale spatial structure for this population. We conclude that both survey methods may be very useful in population assessment, but they need intense field effort and careful statistical design. Care needs to be taken to satisfy the assumptions of the statistical models. Copyright © 2002 John Wiley & Sons, Ltd.

Pollen and spore keys for Quaternary deposits in the northern Pindos Mountains, Greece

Keys for identification of pollen and spores of extant plants in Grevena´Province, northwestern Greece are presented at the lowest commonly achievable taxonomic rank, based on light microscope observation. As the Province includes a range of vegetation from lowland evergreen oak woods, through semi-deciduous and deciduous oak and mixed deciduous forests at middle elevations, to higher altitude beech and pine woods and alpine meadows, the keys cover most common pollen and spores encountered in Quaternary deposits in upland areas of southeastern Europe. Special attention has been paid to closely identifying pollen and spores of particular interest to the archaeologist. Based on compilations of existing data and new observations, separate special keys are included for Caryophyllaceae, Cyperaceae, Gramineae, Malvaceae, Plantaginaceae, and Rosaceae. A full list of species included in each pollen type is provided.

Orthotrichum acuminatum H. Philib. and Orthotrichum philibertii Venturi (Musci): new species to the Sicilian bryoflora

Summary Orthotrichum acuminatum H. Philib. and Orthotrichum philibertii Venturi: new species to Sicilian bryoflora.—Orthotrichum acuminatum H. Philib. and O. philibertii Venturi, regarded as extinct in Italy, have been collected from new localities of the Nebrodi mountains, the Madonie mountains, the Etna mountain and Rocca Busambra (a mountain to the south of Palermo). They occur in deciduous or evergreen oak woods on a remarkable range of phorophytes: Quercus sp.pl., Acer campestre L., Crataegus monogyna Jacq. and Castanea sativa Miller. The distribution is mapped and the ecology of the species is discussed.

The nutritional carrying capacity of four Mediterranean habitats for Fallow Deer (Dama dama)

The assessment of the trophic value of the most consumed feed by fallow deer in a coastal mediterranean landscape (Rubus ulmifolius, Cistus salvifolius, Phyllirea latifolia, Quercus ilex and graminoids) was based on in vitro digestibility trials, performed throughout the year (1 set of samples per season) using rumen inocula from wild fallow deer from the Preserve of Castelporziano, collected simultaneously with the vegetal samples. Moreover, in vivo digestibility coefficients have been estimated by using standard feed (for fallow deer) of known in vivo digestibility. Using the digestibility coefficients, the metabolizable energy yield of studied forage items was computed. Information about plant biomass, structure of fallow deer population, metabolizable energy yields, estimates of forage intake and energy requirements were combined using the model presented by Hobbs & Swift (1985) to evaluate the nutritional carrying capacity of four typical mediterranean habitats (natural evergreen oak wood, scrub, mixed plantations of Quercus ilex and Pinus pinea, open pastures). Spring represents the most favourable situation, while summer, autumn and winter exhibit similar values of carrying capacity of about 15-20 deer/100 ha. Mixed plantations of Pinus pinea and Q. ilex seem to be the most productive condition for fallow deer.

Mycocoenological research on evergreen oak woods in the hills adjacent the Maremma coastline (NW of Grosseto, Italy)

Relations entre les groupements fongiques (mycocenoses) et les facteurs du milieu identifies au moyen des associations vegetales

Coenological research on macrofungi in evergreen oak woods in the hills near Siena (Italy)

For a mycocoenological study of macromycetes in Mediterranean evergreen forests in the Siencese province, five stands belonging to theQuercion ilicis have been observed during more than two years.

Estructura y funcionalismo de un encinar montano en el Montseny. II: biomasa arbórea

Above-ground tree biomass data are reported as first results of a study on the structure and dynamics of the tree stratum in the evergreen-oak wood at La Castanya (Montseny, Barcelona). 15 evergreen-oaks (Quercus ilex L.ssp ilex) were fallen from a spot near the experimental plot. An alometric table for the evergreen-oak is given, together with estimates of the total above-ground tree biomass for the experimental plot, partitioned in wood 0>5 cm, wood 0 < 5 cm, bark, and leaves by leave-age. Results are compared with those from evergreen-oak woods obtained by other workers.

Estructura y funcionalismo de un encinar montano en el Montseny. IV: producción de hojarasca

Litterfall and its concomitant mass and nutrient (Na, K, Ca and Mg) fluxes to the forest floor are studied in a montane-Mediterranean evergreen-oak (Quercos ilex L.) wood at La Castanya (Montseny, Barcelona). Litterfall is colected biweekly in 16 (only 8 during the first 6 months) conical, 0.25 m litterfall traps randomly distributed over a 0.22 ha experimental plot. Results from the first year of study (May 1978 - May 1979) are reported in this paper. Litterfall a mounted to 4.5 t ha-1 yr-1, not including in this figure the branches longer than 40 cm or thicker than 5mm. Leaves represented 3.08 t ha-1 yr-1 (68.11% of litterfall), twigs 1.05 t ha-1 yr-1 (23.22%), and fruits and inflorescences 0.14 t ha-1 yr-l (3.21%). Leaf fall exhibited a distinct seasonal maximum in late spring-early summer, but total litterfall peaked later when an autumn hailstorm and a November windstorm struck the forest. Nutrient contents of freshly-fallen evergreen-oak litter were within the range of published values for this species. Nutrient fluxes in litterfall were (kg ha-1 yr-1): Na 0.76, K 18.28, Ca 41.64 and Mg 5.43. Throughfall data from Roda et al. (1980) allowed to compute the following nutrient fluxes in litterfall plus throughfall (kg ha-1 yr-1): Na 9.1, K 38.0, Ca 64.7 and Mg 9.3.