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On the basis of bottom trawl surveys performed in Anadyr Bay and adjacent waters from 1979 to 2005 and data on commercial statistics, dates of migrations, and the spatial-bathymetric distribution of cod Gadus macrocephalus in different periods of the year are considered. Migrations of cod for feeding to Anadyr Bay begins in May. Its distribution in the summer period in the bay depends on the intensity and location of the Navarin Current and may noticeably vary from year to year. In September, back migration begins, and, by January, main cod aggregations leave the bay. From January to March, most cod winter and spawn beyond the studied area. The largest depths of cod habitation are typical for April (on average, 230 m), and minimal, for August (on average, 86 m).  相似文献   

3.
Fourteen species of echinoderms and their relationships to the benthic structure of the coral reefs were assessed at 27 sites—with different levels of human disturbances—along the coast of the Mexican Central Pacific. Diadema mexicanum and Phataria unifascialis were the most abundant species. The spatial variation of the echinoderm assemblages showed that D. mexicanum, Eucidaris thouarsii, P. unifascialis, Centrostephanus coronatus, Toxopneustes roseus, Holothuria fuscocinerea, Cucumaria flamma, and Echinometra vanbrunti accounted for the dissimilarities among the sites. The spatial variation among the sites was mainly explained by the cover of the hard corals (Porites, Pocillopora, Pavona, Psammocora), different macroalgae species (turf, encrusting calcareous algae, articulated calcareous algae, fleshy macroalgae), sponges, bryozoans, rocky, coral rubble, sand, soft corals (hydrocorals and octocorals), Tubastrea coccinea coral, Balanus spp., and water depth. The coverage of Porites, Pavona, and Pocillopora corals, soft coral, rock, and Balanos shows a positive relationship with the sampling sites included within the natural protected area with low human disturbances. Contrary, fleshy macroalgae, sponges, and soft coral show a positive relationship with higher disturbance sites. The results presented here show the importance of protecting the structural heterogeneity of coral reef habitats because it is a significant factor for the distribution of echinoderm species and can contribute to the design of conservation programs for the coral reef ecosystem.  相似文献   

4.
Pacific halibut Hippoglossus stenolepis is registered in the Anadyr estuary (Bering Sea basin) for the first time: 20 specimens, 18.5–160.5 cm in length, were caught by trawl and longline within the sea portion of the Anadyr River estuary in August 2010 and September 2015 in highly desalted (23.5‰ on average) and heated (6.5°С) water at a depth of 14–30 meters. Halibut is suggested to form feeding groups within the Anadyr Estuary. An opportunity for organized fishing in this region is discussed.  相似文献   

5.
New species of Transcaucasian bryozoans are described: Primorela remota and Pseudoascopora subtilis (order Rhabdomesida) from the Upper Famennian and Anisotrypa hamata (order Trepostomida), Paranicklesopora stupenda, Euthyrhombopora barbara, Primorella testata, Ipmorella clara (order Rhabdomesida), and Taeniodictya vermiculata (order Cryptostomida) from the Tournaisian.  相似文献   

6.
Five new species of stenolaematous bryozoans are described from the Middle Callovian of Moscow City (Krasnopresnenskii Region) and the Moscow Region (Gzhel’ Railroad Station and the quarry between the small towns of Rechitsy and Troshkovo): Entalophora alexeevi sp. nov., Cellulipora retshitsiensis sp. nov., Diplosolen pravus sp. nov., Siphodictyum primarium sp. nov., and Ceata kamushkiensis sp. nov. The last four species belong to the genera that have never been recorded from deposits older than the Lower Cretaceous. The presence of different types of heterozooecia in these bryozoans shows that the functional polymorphism of zooids developed considerably in the class Stenolaemata as early as the Middle Jurassic.  相似文献   

7.
Seasonal changes in the characteristics of chlorophyll fluorescence were studied in the bark of several species of trees originating in various climatic zones: Siberian cedar (Pinus sibirica), larch (Larix sibirica), eastern arborvitae (Thuja occidentalis), pendent white birch (Betula pendula), wild black cherry (Padus virginiana), horse chestnut (Aesculus hippocastanum), red oak (Quercus rubra), Manchurian catalpa (Catalpa bungei), linden (Tilia cordata), goat willow (Salix caprea), Amur cherry (Padus maackii), and apple Korichnaya (Malus domestrica B.). Tree bark has a sufficient amount of chlorophyll for measuring the parameters of chlorophyll fluorescence throughout the year. The relative yield of the variable fluorescence of chlorophyll (F v/F m) can be used to assess seasonal changes in the physiological state of various trees.  相似文献   

8.
Cold-water corals of the Late Pleistocene (21,400–22,500 BP) are recorded from the sea-bottom of two inter-atoll channels (Kardiva Channel at 457-m depth and Malé Vaadhoo Channel at 443-m depth) of the eastern row of the Maldives archipelago. Coral assemblages are composed mainly by Lophelia pertusa and secondarily by Madrepora oculata and Enallopsammia rostrata. These cold-water coral patches are places where the benthic life, mainly sessile, is concentrated, which is clearly absent off-rubble patches. The main epibionts are tube-dwelling polychaetes (mainly Spirorbis and Serpula), bryozoans, siliceous sponges, barnacles, gorgonids, solitary corals, encrusting foraminifera, and microbial mats. The analysis of epibionts assemblages shows different biocoenoses between both studied sites as well as a dependency of the epibiont coverage with regard to the coral genus. Some living benthic organisms such as brachiopods, bivalves, gastropods, barnacles, and ophiuroids find refuge among coral branches. The common record of juvenile specimens of vagile organisms such as small ophiuroids, is probably related to the nursery function of the cold-water corals in spite they are fossils. Environmental requirements of Recent cold-water corals (Lophelia, Madrepora and Enallopsammia) differ of conditions at both sampling sites with sensibly lower oxygenation degree and density of waters than needed for cold-water corals. Therefore, it is proposed that the present-day oxygen and density conditions are the factors which inhibit modern cold-water coral growth in the inter-atoll channels.  相似文献   

9.
Mesophotic reef fish assemblages (30–90 m depth) of the small and remote St. Peter and St. Paul’s Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil, were characterized using remotely operated vehicles. Ordination analyses identified distinct fish assemblages in the upper (30–50 m) and lower (50–90 m) mesophotic zones, the former characterized by high abundances of species that are also abundant at euphotic reefs (Caranx lugubris, Melichthys niger, Stegastes sanctipauli and Chromis multilineata) and the latter dominated by two mesophotic specialists (Prognathodes obliquus and Chromis enchrysura). Planktivores dominated fish assemblages, particularly in the upper mesophotic zone, possibly due to a greater availability of zooplankton coming from the colder Equatorial Undercurrent in mesophotic depths of the SPSPA. Turf algae, fleshy macroalgae and scleractinian corals dominated benthic assemblages between 30 and 40 m depth, while bryozoans, black corals and sponges dominated between 40 and 90 m depth. Canonical correspondence analysis explained 74 % of the relationship between environmental characteristics (depth, benthic cover and complexity) and structure of fish assemblages, with depth as the most important independent variable. Juveniles of Bodianus insularis and adults of P. obliquus and C. enchrysura were clearly associated with branching black corals (Tanacetipathes spp.), suggesting that black corals play key ecological roles in lower mesophotic reefs of the SPSPA. Results from this study add to the global database about mesophotic reef ecosystems (MREs) and provide a baseline for future evaluations of possible anthropogenic and natural disturbances on MREs of the SPSPA.  相似文献   

10.
We describe two new species of esthonioporate bryozoans, Revalotrypa inopinata sp. nov. and R. yugaensis sp. nov., from the Lower Ordovician, south-east of Lake Ladoga, north-western Russia. The colonies of the two species are very small and were extracted from limestone nodules found in the lower part of glauconitic sandstone in the Joa Member (lowermost Floian). Revalotrypa inopinata sp. nov. and R. yugaensis sp. nov. are the oldest known bryozoans from Baltoscandia. Study of the two species includes scanning electron microscopy (SEM) imaging and X-ray microtomography (micro-CT). The palaeogeographic distribution of the oldest known bryozoans from the Lower Ordovician and the advantages and disadvantages of micro-CT for the study of Palaeozoic bryozoans are discussed. The authorship of Revalotrypidae, which has been inconsistently allocated in the literature, is discussed.  相似文献   

11.
We studied the distribution of the “bitter-crab” syndrome, a disease caused by the parasitic dinoflagellate Hematodinium sp., in eight commercial species of crabs in the west of the Bering and Chukchi seas. The crabs (25 388 individuals) were sampled during bottom trawl surveys of July?September 2010 and October?November 2012. The disease was first identified visually by a color change of the exoskeleton and the hemolymph of the animals and then using microscope analysis of hemolymph samples. Infestation was detected in crabs of three species, Chionoecetes opilio, C. bairdi, and Paralithodes platypus. The prevalence of the disease (the percent of infected individuals relative to all of those examined) in C. bairdi and P. platypus was very low, 0.1 and 0.3%, respectively. Infestation was widespread among C. opilio, its peak in the Bering Sea was in the fall. The average prevalence of the crab disease in different areas of the Bering Sea ranged from 0.8 to 10.8%. A high rate of crab infection was recorded in the Korfa Bay. In the Chukchi Sea, the average prevalence was 2%. Infestation by Hematodinium sp. was not revealed in the deep-sea snow crabs Chionoecetes tanneri and C. angulatus, and in three species of lithodid crabs, Paralithodes camtschaticus, P. brevipes, and Lithodes couesi. This can be explained by the small sample volume and/or ecology of these species, since the disease was registered in other areas in four of them.  相似文献   

12.
Earlier, it has been shown that genes responsible for differences in longevity between wild-type Drosophila melanogaster lines 2b and Oregon are localized in region 7A6-B2, 36E4-37B9, 37B9-D2, and 64C-65C. Quantitative complementation tests were conducted between the gene mutations localized in these regions and involved in catecholamine biosynthesis (iav (inactive), Catsup (Catecholamines up), amd (alpha metil dopa-resistant), Dox-A2 (Diphenol oxidase A2), ple (pale)) and neuron development control (Fas3 (Fasciclin 3), tup (tail up), Lim3), on the one hand, and two different normal alleles of these genes in lines 2b and Oregon, on the other. Complementation was found for genes iav, Fas3, amd, and ple. The remaining genes (Catsup, Dox-A2, tup, and Lim3) are candidate genes for controlling differences in longevity between lines 2b and Oregon.  相似文献   

13.
The expression of L-lactate dehydrogenase genes ldh1 (Bos taurus), ldhA (Homo sapiens), ldhA (Rhizopus oryzae), ldh1 (Lactobacillus plantarum), and ldh1 (Lactobacillus pentosus) in the cells of yeast Schizosaccharomyces pombe VKPM U-3106 has been investigated. The catalytic characteristics of the enzymes encoded by these genes have been compared, and the intensity of lactic acid synthesis by the recombinant strains obtained has been evaluated. The enzymatic activity of L-lactate dehydrogenases from L. plantarum and L. pentosus was the highest (approximately 2 to 2.5 times higher than that of the mammalian enzymes), and these enzymes therefore appear to have the highest potential for the development of lactic-acid producing strains of yeast S. pombe.  相似文献   

14.
Photosynthetic parameters including net photosynthetic rate (PN), transpiration rate (E), water-use efficiency (WUE), and stomatal conductance (gs) were studied in indoor C3 plants Philodendron domesticum (Pd), Dracaena fragans (Df), Peperomia obtussifolia (Po), Chlorophytum comosum (Cc), and in a CAM plant, Sansevieria trifasciata (St), exposed to various low temperatures (0, 5, 10, 15, 20, and 25°C). All studied plants survived up to 0°C, but only St and Cc endured, while other plants wilted, when the temperature increased back to room temperature (25°C). The PN declined rapidly with the decrease of temperature in all studied plants. St showed the maximum PN of 11.9 μmol m?2 s?1 at 25°C followed by Cc, Po, Pd, and Df. E also followed a trend almost similar to that of PN. St showed minimum E (0.1 mmol m?2 s?1) as compared to other studied C3 plants at 25°C. The E decreased up to ≈4-fold at 5 and 0°C. Furthermore, a considerable decline in WUE was observed under cold stress in all C3 plants, while St showed maximum WUE. Similarly, the gs also declined gradually with the decrease in the temperature in all plants. Among C3 plants, Pd and Po showed the maximum gs of 0.07 mol m?2 s?1 at 25°C followed by Df and Cc. However, St showed the minimum gs that further decreased up to ~4-fold at 0°C. In addition, the content of photosynthetic pigments [chlorophyll a, b, (a+b), and carotenoids] was varying in all studied plants at 0°C. Our findings clearly indicated the best photosynthetic potential of St compared to other studied plants. This species might be recommended for improving air quality in high-altitude closed environments.  相似文献   

15.
The microbial community of Baikal sponges has been studied in five species belonging to the genera Swartschewskia, Baicalospongia, and Lubomirskia of the endemic family Lubomirskiidae. The results show that the total numbers of bacteria and bacterioplankton production have an effect on the growth of L. baicalensis body. Bacteria of the genera Pseudomonas, Bacillus, Micrococcus, Sarcina, Flavobacterium, Arthrobacter, and Acinetobacter living in the sponges are representatives of the Baikal bacterioplankton. Actinomycetes of the genera Streptomyces and Micromonospora are a permanent component of the cultivable sponge microbial community. The numbers and enzyme activities of heterotrophic, oligotrophic, and psychrophilic bacteria isolated from different sponge species and from the ambient water in autumn and in winter have been estimated.  相似文献   

16.
The 23 polymorphic variants in genes encoding the enzymes of xenobiotics biotransformation (CYP1A1 (rs4646903), CYP1A2 (rs762551), GSTP1 (rs1138272, rs1695), GSTM1 (del), and GSTT1 (del)), DNA repair (XRCC1 (rs25489, rs25487), APEX1 (rs1130409), hOGG1 (rs1052133), ADPRT (rs1136410), XPD (rs13181), XPG (rs17655), XPC (rs2228001), ATM (rs1801516), NBS (rs1805794), XRCC2 (rs3218536), and XRCC3 (rs861539)), antioxidant system (MnSOD (rs4880) and GPx1 (rs1050450)), cell cycle control and apoptosis (TP53 (rs1042522)), DNA methylation (MTHFR (rs1801133) and MTR (rs1805087)), and chromosomal aberrations in lymphocytes in the workers at thermal power plants were analyzed. We found that allelic variants in the CYP1A1 (rs4646903), hOGG1 (rs1052133), XRCC1 (rs25487), and APEX1 (rs1130409) genes were associated with an increased level of chromosomal aberrations in workers. Informative models of gene-gene interactions including CYP1A1 (rs4646903, T>C), CYP1A2 (rs762551, C>A), GSTT1 (del); XRCC1 (rs25487, G>A), MTHFR (rs1801133, C>T), GSTT1 (del); XRCC1 (rs25487, G>A), APEX1 (rs1130409, T>G), TP53 (rs1042522, G>C) determining the formation of the increased frequency of chromosomal aberrations in the workers at coal thermal power plants were discovered.  相似文献   

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The spatial distribution of epifauna in the Far Eastern Marine Reserve was examined using a remotely operated vehicle. The abundance and distribution patterns of the sea stars Patiria pectinifera, Distolasterias nipon, and Asterias amurensis, as well as those of brittle stars, the black sea cucumber Cucumaria japonica, the sea urchin Strongylocentrotus intermedius, the ascidian Halocynthia aurantium, hermit crabs, and the Japanese scallop Mizuhopecten yessoensis were determined in the South Section of the Reserve. The average biomass of five dominant epifaunal species ranged from 51.0 to 87.4% of the average biomass of the softbottom communities.  相似文献   

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