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61.
Angela Aparecida Moreira Acácio Ribeiro Gomes Tomás Alexandre Wagner Silva Hilsdorf 《Journal of experimental marine biology and ecology》2011,407(1):34-40
Octopus vulgaris is a cephalopod species in several oceans and commonly caught by artisanal and industrial fisheries. In Brazil, O. vulgaris populations are mainly distributed along the southern coast and have been subjected to intensive fishing during recent years. Despite the importance of this marine resource, no genetic study has been carried out to examine genetic differences among populations along the coast of Brazil. In this study, 343 individuals collected by commercial vessels were genotyped at six microsatellite loci to investigate the genetic differences in O. vulgaris populations along the southern coast of Brazil. Genetic structure and levels of differentiation among sampling sites were estimated via a genotype assignment test and F-statistics. Our results indicate that the O. vulgaris stock consists of four genetic populations with an overall significant analogous FST (ΦCT = 0.10710, P < 0.05) value. The genetic diversity was high with an observed heterozygosity of Ho = 0.987. The negative values of FIS found for most of the loci examined suggested a possible bottleneck process. These findings are important for further steps toward more sustainable octopus fisheries, so that this marine resource can be preserved for long-term utilization. 相似文献
62.
63.
Pedro María Alarcón-Elbal Sarah Delacour Estrella Ignacio Ruiz Arrondo Francisco Collantes Juan Antonio Delgado Iniesta José Morales-Bueno Pedro Francisco Sánchez-López Carmen Amela María José Sierra-Moros Ricardo Molina Javier Lucientes 《Memórias do Instituto Oswaldo Cruz》2014,109(6):782-786
In 2004, Aedes (Stegomyia) albopictus (Skuse, 1894) was observed for
the first time in Catalonia, northeastern Spain. A decade later, it has spread
throughout the eastern Mediterranean region of the country and the Balearic Islands.
Framed within a national surveillance project, we present the results of monitoring
in 2013 in the autonomous communities of the mainland Levante. The current study
reveals a remarkable increase in the spread of the invasive mosquito in relation to
results from 2012; the species was present and well-established in 48 municipalities,
most of which were along the Mediterranean coastline from the Valencian Community to
the Region of Murcia. 相似文献
64.
Joy A. Fritschle 《Restoration Ecology》2012,20(6):679-687
Old‐growth forests in the American West typically represent fragments of former, more extensive forests that were subjected to nineteenth and twentieth century land‐clearing activities, such as logging. These present‐day forest fragments are thought to be representative of the former landscape, and thus are capable of serving as living references for guiding restoration of logged forests. Yet how do we determine the extent to which existing old‐growth stands represent the former forest, especially when little of the surrounding original vegetation remains? Historic land surveys conducted prior to significant logging can reconstruct the former forest at the stand level, thereby allowing an analysis of old‐growth patches within the larger historic landscape. This study utilized original Public Land Surveys to assess the applicability of old‐growth stands in Redwood National Park as reference ecosystems. A geographic information system (GIS) and statistical analysis of the nineteenth century forest found that vegetation communities, woody species composition, and ratios of dominant canopy species in unlogged patches were highly representative of the forests that were logged. Significance testing (Ho: μ1 = μ2) revealed p‐values greater than 0.10000 in all measures of community and species composition, except for the higher abundance of oak in present‐day old‐growth (p‐value = 0.0395). The results of this study suggest that the national park should increase efforts to protect old‐growth reference ecosystems from further human impacts, and minimize ongoing degradation from edge effects by prioritizing restoration of adjoining second‐growth forest. 相似文献
65.
66.
Kaori Ohki Mitsunobu Kamiya Daisuke Honda Shuzo Kumazawa Kwok Ki Ho 《Journal of phycology》2008,44(1):142-151
Six unicellular diazotrophic cyanobacteria were isolated from the coast around Singapore. The isolates grew under both light:dark (L:D) cycles and continuous illumination (CL) in media without combined nitrogen and exhibited an ability to fix nitrogen (as measured by acetylene reduction) under aerobic conditions. The cells of all isolates were surrounded by a thick fibrous outer wall layer, and they divided by transverse binary fission. The arrangement of photosynthetic thylakoids was of the dispersed type. Three isolates were identified as form‐genus Gloeothece as cells were divided in a single plane, and the other three isolates were identified as form‐genus Gloeocapsa as cells were divided in multiple planes. Phylogenetic analyses based on the DNA sequences of the genes encoding 16S rRNA and dinitrogenase reductase (nifH) revealed the following: (i) Our six isolates formed a monophyletic cluster. (ii) The monophyletic cluster was subdivided into two phylogenetic groups, which taxonomically corresponded with the form‐genera Gloeothece and Gloeocapsa. However, (iii) a diazotrophic strain of form‐genus Gloeothece, Gloeothece membranacea (Rabenh.) Bornet PCC6501, was not closely related to our isolates, and (iv) some, but not all, diazotrophic unicellular strains of form‐genus Cyanothece were observed to be in a close relationship with our isolates. 相似文献
67.
The mitten crab, Eriocheir sensu stricto , is economically important in East Asia, although it is an invasive species in Europe and North America. Little is known about its population structure and historical demography in its native range, especially along the Pacific coast of China. We collected mitochondrial cytochrome oxidase subunit II and cytochrome b sequences from 154 individuals distributed in the rivers along the Chinese coast and 15 individuals from Japan. Phylogenetic analysis resulted in three major monophyletic groups: northern China, southern China and Japan. Negligible migration was detected among those groups by coalescent analysis. Hence, we support the recognition of three species: Eriocheir hepuensis in southern China, Eriocheir sinensis in northern China and Eriocheir japonica in Japan. The populations in the middle (the Oujiang and Minjiang Rivers) possess a mixture of haplotypes similar to either the northern or the southern haplotypes. We believe that secondary intergradation as the most likely cause of the clinal variation based on examining the genetic variation in the latitudinal space. The estimated divergence time between E. sinensis and E. hepuensis is 2.24 million years ago (Ma), while the divergence time between E. japonica and E. sinensis is 1.83 Ma. Both are in the late Pliocene, suggesting that land bridges associated with low sea level during that time might have severed as vicariant barriers for speciation. The divergence of the northern population and the 'northern haplotypes' in the middle population was estimated at 0.12 Ma, while the time separating the southern population and the 'southern haplotypes' in the middle populations was estimated as 0.16 Ma, implicating possible secondary contact in the late Pleistocene. 相似文献
68.
《Harmful algae》2017
In this study the plankton diversity in 13 environmental samples from Varna Bay (in the western Black Sea) was analyzed using massively parallel sequencing (MPS). This preliminary study was undertaken to assess the potential of this technology for future implementation in monitoring programs in the Black Sea. Amplicon sequences of the 18S rRNA gene (V4-5 regions) were obtained using the Illumina MiSeq 250PE platform. A total of 1137 operational taxonomic units (OTUs) were obtained among which 242 OTUs with >0.990 BLAST top hit similarity (21.3% of all detected OTUs) closely related to sequences belonging to −protists. A large portion (175 OTUs = 72.3%) was identified at the species levels, including species typical for the Bulgarian Black Sea plankton community, as well as many that haven’t been reported earlier in the Bulgarian Black Sea coast (124 OTUs = 51.2%). Dinoflagellates were represented by the highest species number (77 OTUs comprising 31.8% of protist species), with dominant genera Gyrodinium and Heterocapsa. The present survey revealed the presence of 12 species listed as harmful, some of which have been previously overlooked, such as Cochlodinium polykrikoides, Karenia bicuneiformis, and Karlodinium veneficum. Species identification was possible for 10.3–36.0% of the detected OTUs in the six major supergroups. The frequency in Rhizaria was significantly lower than that in other major groups (p < 0.05–0.01), implying difficulties in the classification from morphology-based observations. The metagenetic data had an insufficient resolution of the 18S rRNA gene for species identification in many genera. These issues may hamper the implementation of MPS-based surveys for plankton monitoring, especially for detecting harmful algal blooms (HAB). The sequencing technology is steadily improving and it is expected that sequence length and quality issues will be resolved in the near future. The ongoing efforts to register taxonomic information and quality controls in the international nucleotide sequence databases (INSDs) will be essential for improving taxonomic identification power. 相似文献
69.
The occurrence of Cynoscion regalis in Portuguese continental waters is reported for the first time, with six specimens collected in 2015 from three areas: Tagus Estuary, Sado Estuary and Praia da Vieira (central‐west coast). Analyses of morphometric and meristic characteristics confirmed all six specimens as C. regalis; further validation was obtained by sequencing a 675 bp region of the mitochondrial cytochrome c oxidase I gene. These records constitute a range extension of C. regalis into the southern north‐east Atlantic Ocean. 相似文献
70.
From the southern right whale hunting decline to the humpback whaling expansion: a review of whale catch records in the tropical western South Atlantic Ocean
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Igor Oliveira Braga de Morais Daniel Danilewicz Alexandre Novaes Zerbini William Edmundson Ian B. Hart Guilherme Augusto Bortolotto 《Mammal Review》2017,47(1):11-23