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1.
Abstract

Fine roots represent a small proportion of total plant biomass however they represent the most dynamic component of the root systems of woody plants. There is limited information on the beech fine root production in Mediterranean ecosystems and especially in Greece. We measured live, dead and total fine root biomass (d<2 mm) (LFRB, DFRB and TFRB, respectively) over a growing season in a beech (Fagus sylvatica L.) stand on Paiko mountain, NW Greece, in order to contribute to the generally scarce knowledge of the fine root biomass of beech stands. It was found that TFRB and LFRB increased from May to July and then decreased. LFRB decreased with soil depth while there was no pattern at the change of DFRB with soil depth.  相似文献   

2.
We compared seasonal shelter selection and social behavior of Mesobuthus gibbosus from autumn to mid-summer in two similar phryganic ecosystems, in continental Greece (near Volos city) and in insular Greece (eastern Crete), and in the laboratory under simulated abiotic conditions. Our results showed that shelter selection is a critical indicator of the seasonal social behavior of the species. The abrupt climatic changes in spring caused a differentiation in shelter selection between the cold period (November–February) and the warm period (March–June) at both sites. Sociality was exhibited only during winter in the field and was more extensive under cold conditions in the laboratory. Co-occurrence of scorpions proved to be age-specific, facilitated by population density and by harsh abiotic conditions during winter, and negatively influenced by intraspecific competition, which was higher in continental Greece. The response of scorpions to changes of abiotic factors reveals synchronization of seasonal shelter selection with climatic changes.  相似文献   

3.
Ichthyofauna in the Hellenic freshwaters is quite diverse consisted of 161 species (including 28 non-natives), out of the 546 native species in Pan-European level. However, the status of many aquatic ecosystems is currently degraded as a result of a variety of anthropogenic impacts. This has direct reflection on the conservation status of the indigenous and native fish species whose populations are in many cases declining in favor of the invasive ones. Prussian carp (Carassius gibelio) is probably the most dominant invasive species and currently is considered as naturalized in about 26 lake and river basins. Its successful adaptation and proliferation is mainly attributed to its dual reproductive mode (allogynogenetic and gonochoristic), the opportunistic-omnivorous feeding habits and the ability to withstand and flourish in adverse ecological conditions. Accordingly, it exerts competitive, as well as destructive effects upon the indigenous fish species (sperm parasitism, antagonism for food, spawning grounds and spawning substrates) and therefore, efforts are needed to sustain a relative balance of the populations. This review aims to critically discuss the status of C. gibelio in Greece, the intrinsic causes of establishment and the observed impacts on ecosystems. Finally, reasonable actions are proposed related to exploitation of C. gibelio stocks and a path model for the protection of native fish species and their ecosystems.  相似文献   

4.
Origanum onites, widely used as a spice, grows wild in southern and southeastern Greece, especially in phryganic ecosystems. Like other woody plants of these ecosystems, it is characterized by seasonal dimorphism, an adaptation to face the summer drought. Its range in Greece is defined, and the features of its volatile oil are studied. It appears to be a fairly stable species, both from the morphological and chemical point of view. The high yields in volatile oil and high contents of carvacrol from all populations studied suggest the possibility of further profitable exploitation.  相似文献   

5.
Castanea sativa Mill. is an important species of the Balkan Peninsula with high ecological and economic value. This article contributes to a phytosociological synsystematic approach of the C. sativa plant communities in Greece that covers the southern part of the Balkan Peninsula and describes the ecological parameters involved in their distribution and taxonomy. Phytosociological data have been collected from 14 mountainous areas across continental Greece, which are considered representative of the main forest types of C. sativa in the area. The 14 mountains demonstrate a variety of environmental conditions. Five communities (associations) and seven sub-communities (sub-associations) have been identified and described using TWINSPAN, Corespondence Analysis and the Braun-Blanquet classification scheme. Castanea sativa (chestnut) forests of Greece can be distinguished as three broad groups, defined primarily by their geographical distribution. In northern and central Greece chestnut stands are characterized by their high floristic homogeneity, which is reflected in the identification of only one community per region. Chestnut forests in northern Greece, in particular, exhibit strong floristic similarities with those of the rest of the Balkans. In southern Greece, on the other hand, the southern distribution limit of chestnut in the Balkans, there is a greater floristic diversity between the sampled mountains which is reflected in the presence of three confirmed communities and two sub-associations. Several factors have been identified as important in determining the structure and floristic composition of chestnut forests in Greece. Whilst climate and the grazing regime are influential, the degree of silvicultural management appears to be the most important factor determining the floristic composition of chestnut forests and their long-term sustainability.  相似文献   

6.
In semi-arid Mediterranean environments, fungal activity is fundamental for buffering biotic and abiotic stress to the plant and for sustaining a vegetation cover. Despite the important role that fungi play in habitats stability, mycological data from Mediterranean ecosystems are scarce and fragmentary. We investigated fungal diversity in several areas characterized by Mediterranean maquis, from continental Italy, Sicily, and Greece in order to contribute to the analysis of distribution, ecology, and diversity of macrofungi in evergreen sclerophyllous shrublands at different elevation and distance from the seashore across the Mediterranean Basin. Several fungal taxa that are remarkable due to their ecology, rarity, and limited geographical distribution were recovered. Among them, the ectomycorrhizal species Amanita dunensis and A. valens were recorded for the first time in Italy. The wood-inhabiting macrofungi, Aleurodiscus dextrinoideocerussatus, Peniophorella tsugae, Perenniporia meridionalis, Phanerochaete martelliana, Vararia ochroleuca, and six Peniophora species were reported for the first time in Greece. Some species, such as Gloeodontia columbiensis, Ceriporia aurantiocarnescens, Peniophora pithya, and P. tamaricicola were collected on new substrates. For the two rare basidiomycetes Amanita eliae and Battarrea phalloides, molecular identification and phylogenetic analysis gave valuable information on their relationship with similar taxa.  相似文献   

7.
This paper reports on seeds of Lallemantia (Lamiaceae) found at Bronze Age sites in northern Greece. At several of these sites, the seeds were found in significant concentrations in storage contexts, suggesting that they were deliberately stored for use by the inhabitants. Oil from the seeds of Lallemantia can be used for a variety of purposes, including food, lighting and medicine. This genus is not native to Greece, the nearest modern occurrences of Lallemantia species being in Anatolia from where they extend further east as far as Iran, or beyond. To date, it has not been found in Neolithic deposits in Greece, despite significant archaeobotanical research, especially in northern Greece. This suggests that it first appeared in Greece in the early Bronze Age, and indicates long distance contacts with communities to the east or north at this time. It is difficult to establish whether its continued use indicates that seeds of this genus were repeatedly brought into Greece throughout the Bronze Age or that the genus was introduced in the early Bronze Age and then locally cultivated. The presence of seeds, however, may suggest that Lallemantia was locally cultivated, as it would have been possible to import it in the form of oil. The appearance of a new import or introduction at this time adds to the evidence for external contact during the Bronze Age. Lallemantia may have been part of a group of oil producing taxa which became significant during the Bronze Age in northern Greece paralleling the increased importance of the olive in southern Greece.  相似文献   

8.
Quercus coccifera (kermes oak) is the most common species of the Mediterranean maquis with a wide distribution across the Mediterranean Basin. This paper presents a syntaxonomic overview of the Q. coccifera plant communities in the Mediterranean zone of Greece (Quercetea ilicis) based on the classification of 221 relevés from 34 (17 continental and 17 insular) mountainous areas throughout Greece. Two associations and eight sub-associations are described and presented in a synoptic constancy table. Querco cocciferae–Pistacietum lentisci is the most widespread, is found in the entire continental Greece and most islands, and is further subdivided into five sub-associations reflecting primarily local peculiarities in the disturbance regime and the influence of local floristic elements. Rhamno lycioidis–Cocciferetum (Rivas Goday & Rivas-Martínez 1954), on the other hand, is geographically confined on the island of Crete and is further subdivided into three sub-associations, reflecting differences in the annual precipitation, and they are characterized by the presence of many phryganic and grazing-resistant species. Climate and the anthropogenic pressure have been identified to be the most important factors determining the structure and the floristic composition of Q. coccifera Mediterranean shrublands of Greece.  相似文献   

9.
A new species, Bellevalia juliana Bareka, Turland & Kamari (Asparagaceae) is described from E Kriti (Greece) and compared with other related taxa from Greece and the Mediterranean area. It is a member of B. sect. Bellevalia and a karyological study revealed a hexaploid karyotype with 2n = 6x = 24 chromosomes, illustrated here. The conservation status of the new species is assessed as Vulnerable (VU), according to IUCN criteria.  相似文献   

10.
In order to increase our arachnological knowledge of Greece, and in particular north‐east Greece, an investigation of the arachnofauna of the Aladjagiola wetland complex was conducted from April to July 2008. The study area is part of the Nestos Delta in north‐east Greece, and comprises an area of approximately 20 km2. Spiders were collected from 28 sites using pitfall traps. In all, 6694 specimens were sampled, including 206 species from 31 families. Altogether, 30 and 74 species were new to the districts of Greece and Macedonia, respectively. A number of faunistically interesting species were recorded during the study: Brachythele denieri (Simon, 1916), Camillina metellus (Roewer, 1928), Zelotes cingarus (O.P.‐Cambridge, 1874), Zodarion blagoevi Bosmans, 2009, Zodarion epirense Brignoli, 1984, Zodarion hauseri Brignoli, 1985, and Zodarion pirini Drensky, 1921, are Balkan endemics; Tegenaria angustipalpis Levy, 1996 and Titanoeca turkmenia Wunderlich, 1995 were newly discovered in Europe. Widespread elements represented the largest share of the species inventory, although chorological analysis indicated that the study area, as well as the whole north‐eastern part of Greece, is a reflection of a transition zone from the European fauna towards the Mediterranean and eastern (or Ponto–Anatolian) elements. Taken in combination, these affect the local fauna. The Balkan endemics, although small in number of species, further underline the unique identity of the area. Based on comparisons with data sets from the country's southernmost island, i.e. Crete, Greece can be regarded as a zoogeographical gradient. Hereby, Aladjagiola represents the northern edge, with European and Anatolian elements dominating the species inventory, and Crete represents the southern edge, with widespread but also endemic Mediterranean and eastern elements creating a more local and insular zoogeographical character. In conclusion, Greece cannot be viewed as a uniform zoogeographical unit, but rather as a mosaic of various regional zoogeographical patterns. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 217–233.  相似文献   

11.
Culicoides biting midges (Diptera: Ceratopogonidae) were trapped between 1999 and 2004 at 122 locations in mainland Greece and on most of the larger Aegean and Ionian islands, using OVI light traps, in order to determine the distribution and seasonal activity of bluetongue virus vectors and other Culicoides species. Thirty‐nine Culicoides species were identified, six of which (C. furcillatus, C. impunctatus, C. paolae, C. pictipennis, C. riethi, and C. scoticus) were identified for the first time in Greece. Two of these (C. impunctatus and C. scoticus) may be of veterinary importance due to their role as vectors of bluetongue virus and related orbiviruses. In addition, C. imicola was detected for the first time in mainland Greece.  相似文献   

12.
Information on reproductive biology of the European hare (Lepus europaeus) in different environmental and landscape conditions comprises part of fundamental knowledge regarding species’ adaptive responses as well as many aspects of its biology. Most of the studies conducted on European hare reproduction are confined to midlatitude and northern populations, whereas no data exist on the indigenous southern populations. Here, we present information on reproductive characteristics of European hares inhabiting Mediterranean ecosystems on the island of Crete, Greece for two successive hunting seasons. Although the annual reproductive cycle of the species is well known, with an autumn sexual inactivity, the duration of this period is subjected to fluctuations in different years and for different areas. According to our data, hare populations of Crete present an autumn–early winter reproductive activity with high proportions of pregnant females observed in all the months of the study. Furthermore, the estimated mean litter size (1.54 SE ± 0.07) while signed to the lowest values ever observed for European hares is similar to values obtained in continuous breeding species of the same genus, Lepus granatensis, Lepus corsicanus, Lepus (capensis) mediterraneus, and Lepus capensis also inhabiting warm climates. In conclusion, our results suggest that Cretan European hare populations exhibit a reproductively active period during autumn–early winter where proportions of pregnant females and litter size give a strong indication of a continuous reproduction throughout the year.  相似文献   

13.
14.
Testudo marginata, the largest European land tortoise, is suffering habitat degradation and destruction. Some populations, in markedly degraded habitats, are characterized by divergent morphotypes. However, the evolutionary significance of these morphotypes is of debate. Using 11 polymorphic microsatellites, we studied: (1) marginated tortoises from Sardinia that display a divergent morphotype – this population was potentially introduced from Greece; and (2) an area in the southern Peloponnese that includes a small and degraded zone in which marginated tortoises are dwarf. Genetic analyses run without any a priori assignment clearly acknowledge the specimens sampled in the territory of the dwarf form as a single group whilst Sardinian specimens are clustered with other specimens from the northern part of the area sampled in Greece. Demographic analyses suggest that Sardinian tortoises originated recently from some of the populations sampled in the northern part of the area sampled in Greece. Over locations sampled in Greece, a landscape‐genetic analysis allowed us to detect potential landscape features that may reduce gene flow between the dwarf form territory and surrounding areas. Our results suggest that the territory of the dwarf form is particularly propitious for marginated tortoises and that conservation regulations in Greece should be reinforced to protect this area from increasing impact of human activities changing from traditional agriculture to mechanization and extensive use of chemicals. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 591–606.  相似文献   

15.
The present article extends our previous work on the phylogenetic history of Microtus (Terricola) thomasi, analysing cytochrome b, 12S rRNA, 16S rRNA and the control region in 65 Greek populations. The analysis revealed three clades: one grouping the populations from Peloponnisos (Southern Greece); the second, the populations from Agios (Ag.) Stefanos and Evvoia island (Central East Greece); and the third, all the remaining populations with no geographical substructure. Genetic distances were low for most populations, with only the populations of Evvoia and Ag. Stefanos being substantially distant. Thus, although this species has a recent colonization history and probably descends from a highly polymorphic ancestor, a monophyletic and highly differentiated lineage is formed in Greece and is distributed in Ag. Stefanos and Evvoia. Molecular differentiation, distinct geographical distribution and restriction of gene flow between this lineage and the rest of the Greek populations provide evidence for its probable subspecific status, Microtus (Tericola) thomasi atticus. A possible mechanism leading the differentiation process of the proposed subspecies is suggested, based on the displacement of this species in central Greece by its congeneric, probably better‐fitted Microtus (Microtus) guentheri and the subsequent separation of Ag. Stefanos and Evvoia from the remaining Greek populations. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 117–130.  相似文献   

16.
Vineyard surveys of Corinth raisin cultivar carried out in the Peloponnese region of Greece during 2002 and of wine‐producing grape cultivars (Cabernet Sauvignon and Grenache Rouge) on the island of Rhodes, Greece, during 2003, demonstrated the occurrence of various Aspergillus spp. in berries of bunches at harvest. Aspergillus niger and A. carbonarius were predominantly isolated from sampled berries. Although the prevailing Aspergillus spp. isolates belonged mainly to A. niger aggregate, isolates of A. carbonarius were by far the most efficient Ochratoxin A (OTA) producers as revealed by the enzyme‐linked immunosorbent assay test. This study provides the first evidence concerning the composition of Aspergillus populations in raisin and wine‐producing vineyards and offers convincing data for their ability to produce various levels of OTA in Corinth raisins and wine‐producing grapes in Greece. Furthermore, it demonstrates that chemical applications with the fungicide Switch, especially under low to intermediate Aspergillus infection of vineyards, could both significantly reduce the occurrence of OTA‐producing Aspergillus spp. and restrict sour rot severity. In contrast, vineyard applications with the fungicides Carbendazim or Chorus were ineffective in controlling the fungus in Corinth raisin cultivar.  相似文献   

17.
In the past, sturgeons were practically unknown in Greece, both to the public and to scientists, the latter not having had the opportunity to study wild populations of the four native species. Populations of stellate sturgeon (Αcipenser stellatus Pallas, 1771), Adriatic sturgeon (Acipenser naccarii Bonaparte, 1836), and beluga sturgeon (Huso huso L., 1758) gradually collapsed by the end of the 1970s. Only the River Evros (Thrace, N.W. Greece) sustained a small fishery and caviar canning operation with European sturgeon (A. sturio L., 1758) until 1975. Collapse of stocks was mainly attributed to overfishing, pollution and damming. Sturgeons became widely known after initial farming efforts by the Municipal Hatchery at Lake Ioannina in 1992. Broodstock or fertilized eggs of species with high aquaculture potential, such as sterlet (Acipenser ruthenus L., 1758), Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833), bester hybrid (A. ruthenus ×H. huso), paddlefish (Polyodon spathula Walbaum, 1792), Siberian sturgeon (Acipenser baerii Brandt, 1869) and white sturgeon (Acipenser transmontanus Richardson, 1836) were imported into Greece between 1992 and 2004. Hatchery technology, larval rearing and production systems are reviewed in this paper and, despite problems, past and present efforts appear to meet a particular interest of the aquaculture sector as well as of those interested in the restoration of wild stocks.  相似文献   

18.
Wild common carp from two lakes and two rivers in Greece were genetically characterized with sequencing analysis of two mitochondrial DNA segments: cytochrome b (1119 bp) and D-loop (646 bp). A total of 9 variable singleton sites and 7 unique haplotypes were detected. A common haplotype was found in three out of the four populations examined, which seems to be the ancestral one and represents the European origin of common carp from Greece. This haplotype could be also justified by the introductions reported with individuals belonging to the Central European race, into many natural habitats in Greece. Limited genetic variation — in Evros and Aliakmonas populations — could be due to bottleneck effects and small effective population sizes, whereas the different haplotypes found in Lake Volvi could represent different common carp stocks. Values of sequence divergence among Greek haplotypes ranged from 0.0006 to 0.0023. The Neighbour-Joining (NJ) phylogenetic tree constructed based on the combined sequences, reveals that the populations of common carp from Greece belong to the European group of populations — which is highly divergent from the South East-Asia cluster — and to the subspecies Cyprinus carpio carpio.  相似文献   

19.
Three new species of larval Charletonia Oudemans, 1910 from Rhodes, Greece are described: C. dalegori from an undetermined orthopteran, C. glifadaensis from Oedipoda sp. (Orthoptera: Acrididae: Oedipodinae) and C. kaliksti from Aiolopus sp. (Orthoptera: Acrididae: Oedipodinae). C. krendowskyi is recorded for the first time from Greece. A key to the European species of larval Charletonia is provided.  相似文献   

20.
The structure of the mating call of lake frogs (referred to as R. ridibunda) from 16 populations in Greece was analyzed for local variation using multivariate statistics. The populations of Thrace and of the island of Samothraki form a group giving the same type of mating call, whereas the mating call of the other populations differs in the degree of temperature dependence of four parameters, and specifically in the number of pulses/pulse group and pulse groups/call. Discriminant functions distinguish even single call series with a probability of 97%, intermediate mating calls are absent, and there is a significant, but slight differentiation of external morphological characters. These results have strong taxonomic implications. We conclude that the lake frogs of Greece comprise two species. The mating call of the lake frogs from Thrace resembles in all parameters that of the Rana ridibunda in the terra typica restricta (Guryev, CIS). Accordingly, the lake frogs of eastern Greece belong to R. ridibunda. The mating call of these lake frogs consists of 20 pulses/pulse group and of 7 pulse groups/call on the average. Most of Greece is inhabited by the second taxon, Rana balcanica sp. n. Its mating call is characterized by 27 pulses/pulse group and 4 pulse groups/call on the average. The two species in Greece do not differ with respect to coloration and size, but several standardized indices vary significantly: body length/digitus primus length; body length/callus internus length; body length/snout-eye distance; body length/tympanum diameter; tibia length/callus internus length; maximal head width/snout-eye distance.  相似文献   

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