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91.
The Atlantic lumpsucker Cyclopterus lumpus (343 mm total length) is recorded for the first time from the Mediterranean Sea. The specimen was collected in the night between 16 and 17 September 2004 off Molunat Bay, Croatia, southern Adriatic Sea. This record may present a case of a vagrant specimen.  相似文献   
92.
Chamelea gallina is an infaunal bivalve, widespread in sandy bottoms along Mediterranean coasts. It is an important economic resource for fisheries in the Adriatic, although in recent years over-fishing, and other concurrent factors, have dramatically decreased clam harvesting. In this context, it is of great interest to gain information on seasonal variations in the physiological performance of clams, for an overall evaluation of their well-being. In this study, laboratory experiments were performed to define allometric relationships and effects of temperature on clearance and respiration rates of C. gallina. The mean values of b coefficients were calculated and used to correlate physiological measurements to 'standard' body mass, when seasonally collected clams were analysed. The highest clearance rate (0.42 L h(-1)) was measured in clams collected in July 2000; the highest respiration rate (12.22 micromol O2 h(-1)) was observed in July 2001, leading to a negative scope for growth (-2.8 J h(-1)). The influence of environmental and endogenous factors, mostly reproduction, was discussed. Survival in air and condition indices, showing higher stress conditions in December 2000 and July 2001, were in good agreement with the other physiological measurements. The physiological responses examined in this study appear to be suitable for providing detailed indications on the well-being of C. gallina and may be useful for future studies aimed at eco-sustainable management of the resource.  相似文献   
93.
The relationships between mantle length and number of cuttlebone chambers (or septa), and between weight and number of cuttlebone chambers were studied in Sepia orbignyana collected in the south-western Adriatic Sea. Weight-at-chamber count and mantle length-at-chamber count were statistically higher in females than in males. As the available literature suggests that the rate of cuttlebone septum formation is the same in both sexes of Sepia species, it follows that in S. orbignyana females have higher growth rates than males. Received in revised form: 6 February 2001 Electronic Publication  相似文献   
94.
In this paper we consider the trophic state and ambient nutrient limitation by the trophic index (TRIX) calculation and nutrient enrichment bioassay using the diatom Phaeodactylum tricornutum at two differently eutrophicated NE coastal Adriatic locations (in the Rijeka Bay area). The first station in Rijeka Port had significantly higher concentrations of dissolved inorganic nutrients and TRIX indices (up to 7.53) than the station near Opatija. The DIN/TP ratios in Rijeka Port were lower (11.03 to 44.47) than those in Opatija (38.67 to 82.00), indicating P limitation in Opatija. The nutrient enrichment bioassays revealed P as the key limiting nutrient for the diatom growth at both sites. In addition, silica limitation was found in all water samples with the exception of the surface water samples in Rijeka Port. Nitrogen limitation was rarely evident.  相似文献   
95.
Allium croaticum , a new species from the island of Vis in Central Dalmatia (Croatia) is described and illustrated. Its relationships with allied species belonging to the A. stamineum group (Allium section Codonoprasum) are discussed. It is a diploid species (2n = 16), colonizing calcareous screes and flowering in early summer. Its morphology, leaf anatomy, karyology, palynology, ecology and taxonomic position are examined. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 106–114.  相似文献   
96.
The population dynamics of Pseudo-nitzschia in relation to environmental factors was investigated from March 2002 to July 2008 in Lim Bay, in the north-eastern Adriatic Sea. Domoic acid was monitored in the breeding population of Mytilus galloprovincialis from 2005 to 2008. The principal-component analysis of environmental parameters showed that the system is mostly temperature driven. The phytoplankton community was mainly composed of diatoms. Pseudo-nitzschia was the dominant diatom, present in 60% of samples, with a maximum (1.6 × 106 cells L−1) contribution up to 97% of the total diatom abundance. Morphological analysis revealed Pseudo-nitzschia manii and potentially toxic Pseudo-nitzschia pseudodelicatissima, Pseudo-nitzschia pungens, Pseudo-nitzschia fraudulenta and Pseudo-nitzschia calliantha as the dominant species in blooms. Pseudo-nitzschia abundance positively correlated to temperature, phosphate and ammonia in accordance with its maximal abundance in the summer/autumn period when fish farms had a maximum impact on the environment. Domoic acid was detected in M. galloprovincialis in concentrations below regulatory limits, ranging from 0.097 to 0.8721 μg g−1 in five cases from April to October 2005 in Lim Bay, but so far it is not clear which of the species was responsible for DA production. This study is also the first record of P. manii, P pungens and P. fraudulenta species in the Adriatic Sea.  相似文献   
97.
98.
Three burrow systems produced by Jaxea nocturna and one cluster of burrows produced by Upogebia pusilla where investigated in the Bay of Panzano, Northern Adriatic Sea, to determine preferred orientations. The distributions of dip directions differ between both producers. Steep shafts into the consolidated mud followed by large, shallowly inclined tunnels oriented in a manner similar to a spiral are characteristic for Jaxea nocturna burrows. In contrast, the Y-shaped burrows of Upogebia pusilla have entrance shafts that are less steep which are connected by a near-horizontal section, where a blind ending tunnel branches. Orientations of the dominating, shallowly inclined burrow parts are not randomly distributed in either Jaxea or in Upogebia burrows. Three preferred axial orientations with almost equal proportions in each direction are characteristic for the Jaxea burrow from the centre of the bay. This system transforms to a squared structure near the coast, where one direction parallels the shoreline and the other is oriented at right angles to the coast. The latter orientation demonstrates significant constancy in all investigated burrows. Upogebia burrow clusters coincide with the three preferred orientations of the Jaxea burrow from the bay centre, but the proportions of the directions are unequal. Burrow segments connecting the steep entrance shafts in Upogebia are oriented almost parallel to the shoreline, whereas at right angles to the coast the flat blind-ending tunnels incline towards the open sea. The study shows a strong coincidence between empirical and theoretical distributions of the dominating orientations in both species.  相似文献   
99.
100.
In July 1994, we were able to collect airborne fungal spores and pollen grains over the Adriatic Sea from the upper deck of the Oceanographic Ship Urania (CNR). The biological particles were collected using a modified Lanzoni VPPS 1000 sampler (operating at a flux of 10 LPM), on glycerine-gelatine coated microscopic slides. Not only were the airborne concentrations of different organisms estimated, their viability was also tested with a 1% TTC solution. Particles were collected for 60 min (i.e. a volume of 600 liters of air sampled) at every 2 h from 0600–2100 h. Up to 689 pollen grains/m3 and an impressive 48 990 spores/m3 were collected daily. Forty-two fungal taxa were identified and the most abundant spores collected were Cladosporium (82.6%), Smuts (4.8%), Ascospores (2.8%), Basidiospores (2.1%) andAlternaria (1.7%). 20 pollen taxa were identified, and the dominant pollen were Urticaceae (57.9%), Graminaceae (20.7%), Fagaceae (2.4%), Plantaginaceae (1.4%), Pinaceae (1.3%) and Eucalyptus (1.1%). The most abundant captures were done at 0800 and 1000 h (17.8 and 16.7% respectively) and at 1400 and 1600 h (13.2 and 13.8% respectively). Pollen viability per species ranged from 0 to 100%, but for the most abundant taxa, it ranged from 3.8 to 75%, and averaged 27.7%. Maximum viability was found at 0800 and 1200 h. Pollen concentrations were of the same order of magnitude as the ones found on the mainland (Brindisi, Chieti, Matera). However, its specificity was evident. Future work should therefore look more at the pollen transport process which should account for this different assemblage of pollen.  相似文献   
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