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We studied the factors affecting the distribution of an endemic shrewSorex samniticus Altobello, 1926 in the Province of Siena, central Italy. Distribution data were obtained by examining pellets from 31 barn owlTyto alba sites (roosts) over a period spanning from 1974 to 2005. We constructed a model using logistic regression analysis on presence/absence data. Results show that an increase in forest dominated byQuercus cerris andCastanea sativa led to the local extinction of this species. Results were confirmed through the examination of one box, with 3044 prey items deposited in layers, that documents the expansion of the species in that area following increased logging ofQuercus cerris andCastanea sativa forests. Cessation of logging has again led to the absence of the species from the area. We discuss these results from the perspective of ecological network planning, showing that utilisation of non-detailed maps, such as Corine Land Cover, that do not distinguish between the various kind of broadleaved forests is inadequate to describe the finer grade of habitat selection of this small mammal.
Tamarix duezenlii, belonging to Tamarix L. ser. Leptostachyae (Bunge) Baum, is described as a species new to science. It is related to T. hispida Willd. and T. arborea (Sieber ex Ehrenb.) Bunge. From the former species it differs by its dense inflorescences, white petals and paralophic disc; from the latter by a shrubby habit, elliptic petals and calyx abruptly narrowed at the base. The species occurs in saline areas of the Cukurova Deltas at the mouths of the Seyhan and Ceyhan rivers in southern Turkey.
This study was addressed to environmental factors significantly influencing the habitat preferences of endemic species and to obtain a model of their common habitat preferences in the Aglasun district. The district, covering an area of 55,000 hectares, is located in the lakeland subregion of the Mediterrranean region, Turkey. Data were collected from 199 sample plots (20 × 20 m ) and in total 40 endemic taxa was recorded in 124 plots which include minimum one endemic species. Wilcoxon rank-sum statistic and Pearson chisquared tests were used for continuous and categorical explanatory variables, respectively. The factors playing important roles in habitat preferences of endemic species were following: altitude, radiation index, soil texture, landscape position and landform. Generalized additive model was used for modelling the habitat preferences of endemic taxa. To obtain the best model, all significant environmental factors were evaluated by selecting stepwise option. Finally, the best model was obtained (training AUC = O.816, and crossvalidation AUC = 0.800) by using altitude and landform variables.
Distributional relationships among closely related taxa can provide key information about the levels of their reproductive isolation or compatibility, and thus the stage of speciation process. Here, we present new information on the sites where two taxa traditionally considered as subspecies of the Subalpine Warbler Sylvia cantillans, S. c. cantillans and S. (c.) moltonii, breed sympatrically in mainland Italy. We analyse geographic distribution and behaviour as well as other characteristics shown by these warblers in the areas of contact. The distributional pattern shown by these taxa, which is partly sympatric with syntopic breeding, and the apparent lack of interbreeding, strongly suggest that they behave as different species, confirming previous findings about genetic divergence and differential song perception.
The Mediterranean Region is the major area devoted to olive tree crop, and therefore a study of olive flowering is of great interest for the European Community. On the other hand, olive pollen is one of the main causes of pollen allergy in the Mediterranean area. Olive flowering is affected by climatic factors such as temperature and photoperiod, which vary geographically in latitude and altitude. Temperature has been used to study those processes that lead to flowering in the olive tree. The aim of the present paper is firstly the comparison of the flowering full bloom dates in two Mediterranean areas, Sicily (Italy) and Cordoba (Spain), located in the same latitudinal band (37-38oN) and to calculate the heat requirement until flowering by determination of different threshold temperatures and methods of heat accumulation. A delay of the full flowering dates in the Spanish compared with the Italian olive groves was observed. The most suitable threshold temperatures were carried out in a 7-15oC range by considering the heat accumulation start on 1 January in each olive grove. In particular, some causes were indicated as responsible for the different threshold temperatures recorded in the 2 study areas: First, the different climatic conditions (continental and insular climate) secondly the different cultivars present in the olive groves.
Feeding trials were carried out with a captive adult badger Meles meles (Linnaeus, 1758) to establish relationships (digestibility coefficients) between the biomass of freshly consumed food and the dry undigested remnants recovered from scats (bone, teeth, hair, feathers, exoskeleton parts, seeds, etc). The foods studied were those revealed by our research to be the principal components of badger diet in a Mediterranean environment, and the values of the digestibility coefficients (DC) were: 24.74 for rabbits Oryctolagus cuniculus, 21.72 for rodents, 19.81 for pigeons Columba sp., 99.50 for amphibians, 32.35 for arthropods imago, 44.39 for insect larvae, 18.45 for earthworms Lumbricus rubellus, 2.75 for acorns Quercus sp., 9.19 for arbutus Arbutus unedo, 12.25 for blackberries Rubus ulmifolius, 46.12 for figs Ficus carica, 34.87 for loquats Eriobotrya japonica, 10.94 for olives Olea europaea, and 12.02 for pears Pyrus bourgaeana. The variability of DC values was measured, and attributed to the heterogeneity of constituents of the selected food types. There was no statistically significant correlation between the average weight of consumed food and the digestibility coefficients, confirming the expectation that such coefficients must be derived empirically for each food type.
Krüper’s Nuthatch (Sitta krueperi, Passeriformes) is small-area confined species and it mainly occurs in Anatolia in Turkey, but small numbers are found on the adjacent Lesvos Island and the Caucasus region. It is considered as a “near” threatened species by IUCN. Breeding success of Krüper’s Nuthatchs, which use nest cavities excavated by woodpeckers or make their own entrance holes in slightly decayed old tree trunks, is about 72% fledged birds and main food is composed of Coleoptera and Lepidoptera. Although this species is mainly confined to red pine (Pinus brutia) forest, it occurs also in the other coniferous habitats. Krüper’s Nuthatch was surveyed in four regions of Mediterranean Turkey: the Antalya, Central Taurus, Aladağlar region and Amanos Mountains on an area of 27.9 km². Total of 395 point counts were taken in coniferous forests during the breeding season 2005 to explore the factors which affect the population distribution and density. For each point counts following habitat parameters were measured: (1) height of canopy top, (2) height of canopy bottom, (3) tree diameter at breast height, (4) percentage cover (5) average distance between two trees, (6) total number of strata of vegetation and topographic data (altitude, degree of slope, direction of slope, soil texture). The average density of Krüper’s Nuthatch recorded in the all sites was 7.38 ± 0.57 birds km⁻². However, it differs between regions (ANOVA; P <0.0001) with highest density in the Antalya region (12.10 ± 2.10 birds km⁻²), and a decrease to the east with lowest density in the Amanos Mountains (2.42 ± 0.98 birds km⁻²). Krüper’s Nuthatch breeding density was higher in high altitude and in black pine (Pinus nigra) forest. The highest mean density was found in black pine forests (12.69 ±2.4 birds km⁻²; n = 29), followed by Cilician fir (Abies cilicica) forest (11.61 ± 2 birds km⁻²; n = 39), Lebanon cedar forest (Cedrus libani) (8.49 ± 1.8 birds km⁻²; n = 25) and red pine (Pinus burutia) forest (7.75 ± 0.9 birds km⁻²; n = 188) respectively. We also found a negative correlation between the densities of Krüper’s Nuthatch and the total number of strata of the vegetation. High number of the birds occurs in more open coniferous forests. Mature coniferous forests especially black pine forests at high altitudes should be preserved for its conservation in Antalya region.
Some solitary caryophylliid (Caryophyllia, Trochocyathus, and Ceratotrochus) and flabellid (Flabellum) scleractinian corals from Pliocene of Western Mediterranean exhibit long groove−shaped bioersional structures running along the surface of the thecae. They are epigenic structures produced by an episkeletozoan and therefore, they are described as Fixichnia. Here we propose Sulcichnus as a new ichnogenus, with three new ichnospecies (Sulcichnus maeandriformis, S. helicoidalis, and S. sigillum) to name this traces. Sulcichnus is attributed to the activity of polychaetes. Similar structures are recently produced by Lumbrineris flabellicola, a symbiotic eunicid which maintains a commensalistic relationship with solitary corals. In the fossil record, Sulcichnus occurs associated to shallow marine environments whereas their Recent counterparts are described on deep−marine corals. We interpret this as a consequence of a change in the environmental requirements of the coral/worm pair.
The breeding bird community and structural characteristics of vegetation of the last Croatian mediterranean (Istria Penninsula) oak forest (Quercus robur L.) were compared to those in similar continental oak forests in Croatia. The structure and coverage of the vegetation for both forests were estimated. The line transect method was used for analysing bird community and circular plot method for habitat mapping. Densities were calculated for 17 interior forest bird species, giving an average total density of 880.6 ± 81.4 pairs km⁻². In the mediterranean forest typically continental species were missing or present in low densities. Not a single mediterranean species inhabited forest interior. Insectivorous sedentary species dependent on winter prey availability were more numerous in the mediterranean than in continental forest. The results showed that the difference between mediterranean and continental oak forests was greater in quantitative characteristics than in taxonomic composition of the breeding bird community.
This article present a comparison of soluble sugar levels in seeds of Lupinus atlanticus, Lupinus cosentinii, Lupinus palaestinus and Lupinus pilosus, Lupinus hispanicus subsp. hispanicus and Lupinus luteus of Juno variety. Considering that sugars are accumulated in embryos, only the embryonic tissues were used for biochemical analyses. Additionally, the share of testa and embryo in seed tissues was evaluated. The seed-coat thickness was measured using scanning electron microscopy. The seed coat had the largest share in seeds of Lupinus pilosus and Lupinus palaestinus, and the least share in seeds of Lupinus hispanicus subsp. hispanicus and Lupinus luteus of Juno variety. In the seed of Lupinus pilosus the thickness of the seed coat was 1100 µm, while in Lupinus luteus it was 300 µm. The analysed Lupinus seeds accumulated from 73 mg/g d.m. (dry matter of seed embryo) to 155 mg of soluble sugars/g d.m. The highest quantity of oligosaccharides of the raffinose series was found in seeds of Lupinus luteus, while the lowest amount in seed of Lupinus palaestinus. Galactosyl cyclitols appeared in largest amount in seeds of Lupinus palaestinus and Lupinus pilosus, appropriately 41.93 and 33.75 mg/g dm. The lowest amount of galactosyl cyclitols appeared in Lupinus atlanticus, Lupinus cosentinii and Lupinus hispanicus.
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