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This paper uses GIS to describe and evaluate forest fire risk considering the most important factors affecting fire behavior at fine scales. The study was implemented in Yeşilova Forestry Enterprise in the Mediterranean city of Kahramanmaraş, Turkey. To determine an overall fire risk index for the study area, fire risk rating (extreme, high, moderate, or low) was assigned to decision variables (i.e. species composition, stand development stage, stand crown closure, slope, insolation, settlements, and roads) according to their risk potentials. Additionally, the visibility analysis of fire towers was carried out for monitoring of forests in the case study area. Finally, visibility analysis and a forest fire risk map were evaluated together for determining the efficiency of fire towers. Results indicated that more than half of the total forested area (65.7%) was classified as low category in the fire risk map. According to visibility analysis, the existing fire tower was able to monitor only 37% of forest areas; therefore, it was essential to consider new fire towers for monitoring the overall study area. After locating a potential new fire tower in the study area, it was found that about 71.8% of the area was with the visible zones of two fire towers.
Biodiversity is of crucial importance for ecosystem health and functioning. It is thus one of the most important topics in forest ecology. This study focuses on modelling the spatial distribution of vascular plant diversity (H), richness (S) and evenness (E) in the Yukarıgökdere forest district (14667 ha) located in transition zone between Mediterranean and continental climates in the Mediterranean region, Turkey. Species abundance was sampled at 95 sample plots extending from 1000 to 1900 m a.s.l. in order to calculate the response variables (H, S, E). Climatic and topographical data served as explanatory variables. Multiple regression (ML) and classification and regression tree technique (CART) were used to obtain the distribution models of response variables. The better results were provided by CART. That is why visual assessments of the predicted values of the response variables based on (CART) were performed. The explained variances of the model trees were 63.4, 63.1 and 44.5% for H, S and E respectively. Elevation was found to be the most important environmental factor for all response variables. The higher H and S values were found at the east lower part (1000-1150 m a.s.l.) and the west upper part (1500–1800 m a.s.l.) of the district. The evenness (E) shows generally higher relative values in the upper part of the area. The lowest E specifies the area being optimal for tree growing. It is located between 1400 and 1500 m a.s.l., and ranges from the north to the south in the district.
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The study of the strophomenide brachiopods of the subfamily Rafinesquininae present in the main Upper Ordovician sections, representing the Mediterranean margin of Gondwana, has revealed an increase in diversity of the group at the region during that time. The studied collections are from the Moroccan Anti-Atlas, the Iberian and the Armorican massifs, the Iberian Chains, Pyrenees, Montagne Noire, Sardinia, and Bohemia. Two genera of the subfamily Rafinesquininae have been recorded. Of them, the cosmopolitan Rafinesquina is the only one previously reported from the region and Kjaerina is found for the first time outside Avalonia, Baltica, and Laurentia. Additionally, two new subgenera have been described, Kjaerina (Villasina) and Rafinesquina (Mesogeina). Furthermore, the new species Rafinesquina (Mesogeina) gabianensis, Rafinesquina (Mesogeina) loredensis, Kjaerina (Kjaerina) gondwanensis, Kjaerina (Villasina) pedronaensis, Kjaerina (Villasina) pyrenaica, and Kjaerina (Villasina) meloui have been described. In addition, other species of these genera previously known from isolated localities in the region, such as Rafinesquina pseudoloricata, Rafinesquina pomoides, and Hedstroemina almadenensis are revised and their geographic range expanded. The adaptive radiation experienced by the rafinesquinines at the Mediterranean region during middle to late Katian, was probably related to changes in the regime of sedimentation and water temperature caused by the global warming Boda event.
The Lessepsian invasive fish, Lagocephalus suezensis was recorded for the first time in the eastern part of the Libyan coast, adding a new invasive species to the 16 Lessepsian species recorded in the Libyan waters.
Airborne particulate matter (PM) is presently an environmental problem of primary concern, whose role in air quality, climatic and ecological issues is well recognized, though still a matter of extensive investigations (Intergovernmental Panel on Climate Change, 2007).It is of great scientific interest to detect sources of atmospheric particulate matter and quantify their influence on the global and local scales. Unfortunately, emissions are usually not directly available, while PM concentration time series are experimentally accessible, so that the problem often consists in "inverting" these data to determine the region of influence that caused the measured concentration. In this paper we are concerned with an alternative approach to inverse modeling based on backward trajectory analysis (BTA); this approach has the potential to overcome some limitations associated with traditional BTA.We apply this method to the analysis of PM time series from the Monte Cimone observatory, hereafter MCT, a high altitude station on the top of the Italian Northern Apennines, with the aim of estimate the contribution of Saharan dust transport on PM concentration levels registered in the Mediterranean region.
Preservation of foraging habitats is a fundamental approach to bat conservation. Yet, knowledge on the primary foraging sites of Mediterranean bats remains scarce, particularly during the summer when the availability of prey can be limiting. This study was designed to determine in which habitats bats forage in Southern Portugal, during this potentially stressful period. During the summers of 1994 and 1995, bat foraging activity was monitored in representative habitat types using an ultra-sound detector. The number of feeding-buzzes and bat-passes were counted and species identified through the analysis of recorded echolocation calls. None of the recorded species restricted its foraging activity to a single habitat type, but water sites were preferred by most bats. Tadarida teniotis was an exception to this habitat use. Further analysis confirmed that riparian habitats when surrounded by autochthonous broad-leaved forests seem to provide optimal foraging areas for bats during summer. Opposite, water sites within habitats resulting from intensive agriculture or forestry, provide very poor foraging areas. The typical Mediterranean landscape of Iberia, dominated by oak-woodlands and with numerous, scattered and well vegetated water sites, seems to grant optimal foraging habitat for bats during summer. However, this landscape is itself at risk. Current production demands are causing substantial land-use changes and, despite some European programmes on the preservation of Mediterranean oak woodlands and their biodiversity, the furtherance of this landscape is at stake. The preservation of traditional management strategies of oak-woodlands and associated water sites should be strongly encouraged.
The number of ground-nesting bird species in meadows, one of the most vulnerable habitats in the ornithological reserve of Vrana Lake Nature Park has decreased in recent decades. Nest survival rates were investigated in meadows and reed beds using nest predation experiments in late March and in May 2005. Predators damaged 18% of the 50 artificial nests placed in the pasture meadow habitat in March and 22% in May. Daily survival rate of nests were found to be similar in March (97%) and May (96%). In May, 64% of 25 nests located in the reed bed were discovered by the predators, with the daily survival rate of nests (90%) being significantly lower than that of nests in the nearby meadow. The results suggest that the reasons for the decreasing number of nesting bird species may be – instead of the pronounced presence and activity of predators in the area – the shrinkage of meadow area, the lack of buffer zone, the proximity of agricultural lands, and disturbance caused by intensive grazing.
One specimen of the dusky spinefoot, Siganus luridus (Rüppell, 1829) (♀, total length = 17.3 cm, total weight = 87.61 g), a lessepsian migrant, was captured in the Mljet Channel (Southern Adriatic, Croatian coast) on 15 November 2010. This is the second record of this species from the Adriatic, but first well documented and based on the captured specimen. First record occurred earlier in the Northern Adriatic, but was based solely on underwater observations.
The burrowing goby, Trypauchen vagina, is recorded for the first time in the Mediterranean. It is believed that it reached the Mediterranean from the Red Sea, despite the lack of a record from there, due to its well documented presence in the Arabian Gulf.
Two specimens of the west African goatfish, Pseudupeneus prayensis (Cuvier, 1829), were found for the first time off the Tunisian coast, in northern area. They constituted the third Mediterranean record of this fish. Both specimens were studied and described, and some biological observations were reported. Same taxonomic characters were concomitantly determined on two west African goatfish caught off the coast of Senegal, for comparison. The occurrence of Pseudupeneus prayensis in the area and the Mediterranean Sea is discussed and commented.
Knowledge on the effects of land use on community composition and species abundance is crucial for designing realistic conservation strategies, particularly in highly dynamic systems such as Mediterranean agricultural mosaics that are subjected to intensive cultivation. We investigated these effects on the nocturnal bird species occurring in the study area (Stone Curlew Burhinus oedicnemus, Red-necked Nightjar Caprimulgus ruficollis, Barn Owl Tyto alba, Eurasian Scops Owl Otus scops, Little Owl Athene noctua, Tawny Owl Strix aluco, Long-eared Owl Asio otus, Short-eared Owl Asio flammeus and Eagle Owl Bubo bubo) across an agricultural-natural habitat mosaic in Central Spain for three consecutive years. Shares of vineyards, scrubland, herbaceous cropland, water bodies, and roads significantly affected the composition of the nocturnal bird community. Herbaceous cropland and olive groves, which covered 50% of the study area, proved to be neutral for all species. Remnant patches of natural and semi-natural scrubland (around 10% of the study area) and water bodies (only 1.5% of the study area) showed a positive effect on Eagle Owls, Eurasian Scops Owls, Long-eared Owls, and Red-necked Nightjars. Vineyard (35% of the study area) had a negative influence on Eagle Owls, Long-eared Owls, and Eurasian Scops Owls. Our results indicate, first, that the relative extent of land use types was apparently not related with the presence of nocturnal bird species and, second, that natural scrublands and water bodies are key habitats for assuring the persistence of nocturnal birds in agricultural Mediterranean landscapes. Current land planning focused toward land use intensification will likely increase the areas of habitats that are neutral or have adverse effects on nocturnal birds.
Data collected from 85 sample plots in Yazili Canyon Nature Park (deep, limestone valley; length - 6 km, area – 600 ha, height – 100–400 m) located in Mediterranean region (Turkey) yielded 24 endemic vascular plants. The endemic plant diversity and all vascular plant diversity indices were calculated for each sample plot using Simpson index. Regression analysis was performed between environmental factors, plant diversity and canopy closure. Endemic plant diversity showed a positive correlation with vascular plant diversity, and a negative correlation with slope position and altitude. A significant quadric relationship was observed between the endemic plant diversity and aspect variable. RDA (redundancy analysis) and CCA (canonical correspondence analysis) based on linear regressions were applied to determine the environmental factors affecting the distribution of endemic species, and the best model based on total variance explained was selected. According to RDA based on linear regression, habitat selection of endemics is strongly correlated with aspect, slope position and altitude. Lower altitude zone (300–500 m), the north aspect and lower slope including valley bottom of Yazili canyon were observed to be the most suitable areas for endemics.
Background. The shortnose greeneye, Chlorophthalmus agassizi Bonaparte, 1840, is a species with a circumglobal distribution and is among the most abundant commercial fishes in some Mediterranean areas. The knowledge of the biology and ecology of this species is poor and geographically limited, then the aim of this study is to provide a contribution to the knowledge on the reproductive biology of this monoecious deep-sea fish in Sardinian waters. Materials and Methods. In this paper the morphology and the development of the gonads, the mean size at maturity, the monthly evolution in the percent frequency of the maturity stages, and of the indices related to reproduction of the shortnose greeneye were examined. Individuals were caught by trawls, between 270 and 504 m of depth in the Sardinian seas. Results. The ovarian pattern is of an asynchronous type, characterized by releasing of eggs in successive batches. Seven stages of development for the ovary and four for the testis were identified on the basis of macroscopic and histological features. The female portion is the most evident component and shows a later maturation than the male portion. The spawning period is unique and takes place from May to September. Conclusion. The identification of spawning period and the adopted reproductive strategy is essential to obtain a better understanding of its biology and a good management of its fisheries.
A second record of the small Indo-Pacific fish Tylerius spinosissimus (Tetraodontidae) (known as spiny blaasop) was documented at the beginning of 2009 in the waters of Rhodes Island (south-eastern Aegean Sea, Greece). The finding shows the putative establishment of a population of this alien fish in the Mediterranean with a centre the Dodecanese plateau.
The size and shape of the nest are species-specific characteristics that are often associated with environmental factors at the time of breeding. Nests are expected to be larger or thicker in colder environments, although the relationships between nest design and weather differ between species. Here we present the results of an analysis of the external height of the nest wall in Paridae that accepted small standardized nesting boxes for breeding. The study populations were monitored in a relatively cold Mediterranean study area. We found that Coal Tits Periparus ater built higher external nest walls than Great Tits Parus major or Blue Tits Cyanistes caeruleus, after controlling for the first-egg date and clutch size which are assumed to reflect aspects of the quality of the nest builders. Our measures of nest size were not closely associated with the average ambient temperature, but nest walls tended to be shallower when there was more rain. Nest-shape asymmetry, as reflected in the difference in the external height of the nest measured closest to and farthest from the nest-chamber entrance, was observed in all three species, but the average asymmetry was highest in Coal Tits. In asymmetric nests, more nest material was added to the side that was closest to the front wall considered to be the coldest and least protected against harsh weather. Thus, nest size characteristics differ between three ecologically similar species inhabiting the same cavity type in the same coniferous woodland habitat, which would imply that different species do not respond in the same way to the same set of environmental factors.
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