scholarly journals Bivalve mollusk assemblages on São Paulo's northern continental shelf, southeast Brazil

2005 ◽  
Vol 65 (4) ◽  
pp. 717-727 ◽  
Author(s):  
A. Soares-Gomes ◽  
A. M. S. Pires-Vanin
Keyword(s):  
Clustering Analysis ◽  
Biological Diversity ◽  
Permutation Test ◽  
Anthropogenic Activities ◽  
Austral Summer ◽  
Trophic Groups ◽  
Depth Gradient ◽  
Soft Bottom ◽  
Analysis Of Similarity ◽  
Mollusc Assemblages

Soft bottom bivalve mollusc assemblages were sampled along a depth gradient (10 to 100 m) on the northern São Paulo shelf during the austral summer and winter. A one-way analysis of similarity permutation test revealed there was no seasonal difference in the structure of the bivalve assemblages in the area. A clustering analysis indicated 3 groups of stations corresponding to the bathymetric gradient. Both K-dominance curves and Shannon and Pielou indexes showed higher biological diversity and higher evenness for the shallower area. Most of the bivalves found were classified as suspension-feeders, co-occurring with deposit-feeder species, suggesting an absence of negative interactions between these trophic groups. Differences in the frequency of disturbance along the depth gradient caused by wave storms - more common in winter - and also by predation and anthropogenic activities, such as dredging of fishing boats and input of gross sewage, likely explain the higher diversity found on the inner shelf of Ubatuba.

Benthic mollusc assemblages in West Antarctica: taxa composition and ecological insights

2017 ◽  
Vol 68 (11) ◽  
pp. 2095 ◽  
Author(s):  
Sandra Gordillo ◽  
Mariano E. Malvé ◽  
Gisela Moran
Keyword(s):  
Diversity Index ◽  
Benthic Communities ◽  
Austral Summer ◽  
Trophic Groups ◽  
West Antarctica ◽  
Suspension Feeders ◽  
Deposit Feeders ◽  
Wiener Diversity Index ◽  
Mollusc Assemblages ◽  
Group Species

Although different studies in Antarctica have dealt with benthic communities, few studies have focused on molluscan assemblages and their ecology. During the austral summer of 2011, 17 stations between depths of 68.5 and 754m were sampled in West Antarctica using a demersal bottom trawl pilot net on board RV ARA Puerto Deseado. In all, 1848 specimens of shelled molluscs were recorded. Gastropods were the most diverse group (species richness=74) and bivalves were the most abundant (n=1344). Shannon–Wiener diversity index values ranged between 0.58 and 2.99, with great variation at different stations. Cluster analysis using the Bray–Curtis coefficient showed three distinct assemblages types: one dominated by suspension feeders; a second with representatives from different trophic groups, including suspension feeders, grazers, scavengers, predators and deposit feeders; and a third, more differentiated, with few taxa and dominated by deposit feeders. Finally, multivariate analysis suggests that bivalves were more sensitive to temperature, whereas gastropods were more sensitive to depth.

scholarly journals Preface: The Oligotrophy to the UlTra-oligotrophy PACific Experiment (OUTPACE cruise, 18 February to 3 April 2015)

2017 ◽  
Vol 14 (13) ◽  
pp. 3207-3220 ◽  
Author(s):  
Thierry Moutin ◽  
Andrea Michelangelo Doglioli ◽  
Alain de Verneil ◽  
Sophie Bonnet
Keyword(s):  
Biological Diversity ◽  
New Caledonia ◽  
Austral Summer ◽  
South Pacific ◽  
Adaptive Strategy ◽  
French Polynesia ◽  
Biogenic Elements ◽  
General Context ◽  
Western Boundary ◽  
South Pacific Ocean

Abstract. The overall goal of OUTPACE (Oligotrophy to UlTra-oligotrophy PACific Experiment) was to obtain a successful representation of the interactions between planktonic organisms and the cycle of biogenic elements in the western tropical South Pacific Ocean across trophic and N2 fixation gradients. Within the context of climate change, it is necessary to better quantify the ability of the oligotrophic ocean to sequester carbon through biological processes. OUTPACE was organized around three main objectives, which were (1) to perform a zonal characterization of the biogeochemistry and biological diversity of the western tropical South Pacific during austral summer conditions, (2) to study the production and fate of organic matter (including carbon export) in three contrasting trophic regimes (increasing oligotrophy) with a particular emphasis on the role of dinitrogen fixation, and (3) to obtain a representation of the main biogeochemical fluxes and dynamics of the planktonic trophic network. The international OUTPACE cruise took place between 18 February and 3 April 2015 aboard the RV L'Atalante and involved 60 scientists (30 onboard). The west–east transect covered  ∼  4000 km from the western part of the Melanesian archipelago (New Caledonia) to the western boundary of the South Pacific gyre (French Polynesia). Following an adaptive strategy, the transect initially designed along the 19° S parallel was adapted along-route to incorporate information coming from satellite measurements of sea surface temperature, chlorophyll a concentration, currents, and diazotroph quantification. After providing a general context and describing previous work done in this area, this introductory paper elucidates the objectives of OUTPACE, the implementation plan of the cruise and water mass and climatological characteristics and concludes with a general overview of the other papers that will be published in this special issue.

scholarly journals Fish associated with aquatic macrophytes in the Chacororé-Sinhá Mariana Lake system and Mutum River, Pantanal of Mato Grosso, Brazil

2009 ◽  
Vol 69 (1) ◽  
pp. 101-108 ◽  
Author(s):  
EB. Pacheco ◽  
CJ. Da-Silva
Keyword(s):  
Eichhornia Crassipes ◽  
Aquatic Macrophytes ◽  
Biological Diversity ◽  
Aquatic Macrophyte ◽  
Environmental Conservation ◽  
Left Bank ◽  
Mato Grosso ◽  
Analysis Of Similarity ◽  
Eichhornia Azurea ◽  
Macrophyte Species

On the left bank of the Cuibá River, one of the main tributaries of the Pantanal in Mato Grosso, are located the Chacororé and Sinhá Mariana Lakes and the Mutum River, the littoral regions of which are covered with aquatic macrophytes, dominated by the species Eichhornia crassipes and Eichhornia azurea. To examine the ichthyofauna associated with this vegetation, in the year 2003, 3510 fish were collected, distributed among 83 species, and the limnological variables verified near the macrophyte stands where they were sampled. The most abundant and richest order was the Characiformes, followed by the Gymnotiformes and Siluriformes. Analysis of similarity showed a very low, or null, index that the limnological conditions and morphology of the aquatic macrophyte species provide habitat sufficiently homogeneous to give. The limnological conditions and morphology of the aquatic macrophyte species provide a sufficient habitat heterogeneity to give very low, or null, index values. Thus, environmental conservation measures should be more effective in promoting the conservation of the species, given the high levels of biological diversity found in the habitats studied.

Is Canada fulfilling its obligations to sustain marine biodiversity? A summary review, conclusions, and recommendations 1This manuscript is a companion paper to Hutchings et al. (doi:10.1139/a2012-011) and VanderZwaag et al. (doi:10.1139/a2012-013) also appearing in this issue. These three papers comprise an edited version of a February 2012 Royal Society of Canada Expert Panel Report.

2012 ◽  
Vol 20 (4) ◽  
pp. 353-361 ◽  
Author(s):  
Jeffrey A. Hutchings ◽  
Isabelle M. Côté ◽  
Julian J. Dodson ◽  
Ian A. Fleming ◽  
S. Jennings ◽  
...  
Keyword(s):  
Climate Change ◽  
Biological Diversity ◽  
Anthropogenic Activities ◽  
Well Being ◽  
Companion Paper ◽  
Marine Biodiversity ◽  
Management Actions ◽  
New Research ◽  
Research Initiatives ◽  
Developed Nations

Canada has made numerous national and international commitments to sustain marine biodiversity. Given current and potential threats to biodiversity from climate change, fisheries, and aquaculture, we provide a summary review of Canada’s progress in fulfilling its obligations to protect, conserve, recover, and responsibly exploit marine biodiversity. We conclude that Canada has made little substantive progress, when compared to most developed nations, in meeting its biodiversity commitments. Much of Canada’s policy and rhetoric has not been operationalised, leaving many of the country’s national and international obligations unfulfilled in some key areas, such as the establishment of marine protected areas and incorporation of the precautionary approach to fisheries management. We conclude that regulatory conflict within Canada’s Department of Fisheries and Oceans (DFO) and the absolute discretion exercised by the national Minister of Fisheries and Oceans contribute significantly to an unduly slow rate of policy and statute implementation. We recommend new approaches and measures to sustain Canadian marine biodiversity and new research initiatives to support scientific advice to decision-makers. Many recommendations focus on management actions required to meet existing commitments to biodiversity conservation. Overall, we conclude that the most effective strategy is to protect existing biological diversity and to rebuild depleted populations and species to restore natural diversity. By improving and protecting the biodiversity in Canada’s oceans, such a strategy will restore the natural resilience of Canada’s ocean ecosystems to adapt to the challenges posed by climate change and other anthropogenic activities with consequent long-term benefits for food security and social and economic well-being.

scholarly journals Spatial distribution of bivalve mollusc assemblages in the upwelling ecosystem of the continental shelf of Cabo Frio, Rio de Janeiro, Brazil

2005 ◽  
Vol 22 (1) ◽  
pp. 73-80 ◽  
Author(s):  
Abilio Soares-Gomes ◽  
Flavio da Costa Fernandes
Keyword(s):  
Continental Shelf ◽  
Continuous Distribution ◽  
Common Species ◽  
Bivalve Mollusc ◽  
The Other ◽  
Bivalve Mollusks ◽  
Depth Gradient ◽  
The Mean ◽  
Mollusc Assemblages ◽  
Cabo Frio

Bivalve mollusks of the continental shelf of Cabo Frio upwelling ecosystem were sampled monthly from February 1986 to February 1987 along a 30 to 60 m depth gradient. Mactra petiti Orbigny, 1846, and Tellina gibber Ihering, 1907 were constant species in 30 m; Nucula puelcha Orbigny, 1846, Adrana patagonica Orbigny, 1846, T. petitiana, T. gibber, and Corbula patagonica Orbigny, 1846 in 45 m; and N. puelcha, T. gibber, C. patagonica, and C. caribaea in 60 m. The number of rare species was similar along the depth gradient, ranging from six to ten species. The number of common species was higher in 60 m than in 30 m. Some species showed a continuous distribution but changed the frequency and abundance along the bathymetric gradient. The mean density was higher in 45-60 m than in 30 m, ranging from 15.6 ind.m-2, in 30 m, to 68.1 ind.m-2, in 60 m. There was no seasonal change in density nor in the taxocene structure during the studied period. On the other hand, the bivalve assemblage was spatially structured along the depth gradient, showing consistent changes from 30 to 60 m depths. Diversity and richness also follow this distribution pattern.

scholarly journals Hoverflies (Syrphidae: Diptera) in areas contaminated with heavy metals (Cd, Zn, Pb)

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Anna Mielczarek ◽  
Łukasz Mielczarek ◽  
Elżbieta Wojciechowicz-Żytko
Keyword(s):  
Heavy Metals ◽  
Rare Species ◽  
Anthropogenic Activities ◽  
Red List ◽  
Trophic Groups ◽  
Natural Habitats ◽  
Episyrphus Balteatus ◽  
High Species Richness ◽  
Heavy Metal Emissions ◽  
Research Period

Abstract The aim of the research was to study the diversity of hoverflies (Syrphidae: Diptera) living in areas under the influence of heavy metal emissions (Cd, Zn and Pb). Although the area of the Olkusz Ore-bearing Region (OOR), where the research was partially conducted, belongs to the contaminated regions, where a relatively high species richness of Syrphids has been noted. During the research period, a total of 1,180 syrphids, belonging to 165 species were caught, which constitutes 39.76% of all the Polish Syrphidae fauna. These species represented all the trophic groups with the dominance of zoophagous species (48.48%); however, the most numerous (quantitatively abundant) were saprophagous. Among the collected syrphids, common and numerous species, such as: E. arbustorum (LINNAEUS, 1758), E. tenax (LINNAEUS, 1758), Episyrphus balteatus (DE GEER, 1776) and S. pipiens (LINNAEUS, 1758), as well as rare species such as Callicera aenea (FABRICIUS, 1777) (NT), Chalcosyrphus piger (FABRICIUS, 1794) (DD), Epistrophe ochrostoma (ZETTERSTEDT, 1849) (VU), Orthonevra geniculata (MEIGEN, 1830) (DD), Rhingia rostrata (LINNAEUS, 1758) (DD), Sphegina sibirica STACKELBERG, 1953 (LC) and Spilomyia diophthalma (LINNAEUS, 1758) (NT), were noted. Eleven of the collected species have been included in the Polish Red List of Endangered Species. Melangyna ericarum (COLLIN, 1946) is recorded as a new one among the Polish fauna. Numerous observations did not indicate that the area covered by the study was characterised by a significantly lower species diversity compared to other sites. In fact, the samples taken were usually characterised by a relatively high biodiversity. The obtained results may suggest that anthropogenic activities, including those leading to environmental pollution with heavy metals and to a strong transformation of natural habitats, do not completely destroy biodiversity, and in some cases leave space for nature to create habitats where even rare species of organisms such as Syrphidae can develop.

scholarly journals Taxonomic distinctness of soft-bottoms mollusks from Gulf of Batabanó, Cuba

2017 ◽  
Vol 43 (5) ◽  
pp. 856-872
Author(s):  
Arturo Tripp-Quezada ◽  
Marcial Trinidad Villalejo-Fuerte ◽  
Norberto Capetillo-Piñar
Keyword(s):  
Spatial Scale ◽  
Anthropogenic Activities ◽  
Taxonomic Composition ◽  
Taxonomic Distinctness ◽  
Soft Bottom ◽  
Spatial And Temporal Scales ◽  
Applied Ecology ◽  
Class Level ◽  
Species Lists ◽  
Soft Bottoms

Taxonomic distinction is a measure of diversity that has a number of advantages that provides relevant connotation to theoretical and applied ecology. The usefulness of this type of measure as an alternative method for assessing the biodiversity of soft-bottom benthic marine ecosystems was tested using the indices of average taxonomic distinctness (Delta+) and variation in taxonomic distinctness (Lambda+) for mollusk communities of the Gulf of Batabanó (Cuba). For this purpose, inventories of soft bottom benthic mollusk species obtained in the period 1981-1985 and the years 2004/2007 were used. Both species lists were analyzed and compared at spatial and temporal scales. The taxonomic composition, between the period 1981-1985 and years 2004 and 2007, consisted of 3 classes, 20 orders, 60 families, 137 genera and 182 species observed. With the exception of the class level, a non-significant decrease of this composition in 2004 and 2007 was detected. At a spatial scale, a significant decrease in the taxonomic richness was observed in 2004. Significant differences were not detected in Delta+ and Lambda+ to time scale, but at spatial scale, results revealed significant differences that could be attributed to the combined effect of increased anthropogenic activities in the region with hurricane induced effects. These results suggest that the pair of indices, Delta+ and Lambda+, are good descriptors of the biodiversity of soft-bottom benthic mollusk communities in the Gulf of Batabanó.

scholarly journals Impact of climate change on biodiversity of India with special reference to Himalayan region-An overview

2009 ◽  
Vol 1 (1) ◽  
pp. 117-122 ◽  
Author(s):  
Vinod Kumar ◽  
A. K. Chopra
Keyword(s):  
Special Reference ◽  
Biological Diversity ◽  
Global Climate ◽  
Hot Spot ◽  
Anthropogenic Activities ◽  
Control Measures ◽  
Himalayan Region ◽  
Natural Ecosystems ◽  
The World ◽  
Marine Areas

India possesses a distinct identity, not only because of its geography, history and culture, but also because of the great diversity of its natural ecosystems. The panorama of Indian biological diversity is much wider, as it comes under the twelve mega biodiverse (Hot-spot) centers of the world. It contains a great wealth of biological diversity in its forests, its wetlands and in its marine areas which are distributed all over the country. This richness is shown in absolute numbers of species and the proportion they represent of the world total. The great Himalayan region has peculiar identity in the perspective of its unique biogeography. It supports a large number of glaciers, lakes, rivers, flora and fauna due to its variable climate. It has a profound effect on the climate of the subcontinent. But due to anthropogenic activities the global climate has changed since last few decades. The climate of the subcontinent has also adversely affected the biological resources of the country along with that of the Himalayan region. The present paper discusses the various causes responsible for melting and shrinkage of glaciers, decreasing water flow in the major rivers, increasing pressure of extinction of the ecological wealth of the country. It also talks about the control measures and various management steps which can be taken, with special reference to the Himalayan region.

scholarly journals Diversity and abundance of isopod fauna associated with holdfasts of the brown alga Himantothallus grandifolius in Admiralty Bay, Antarctic

2015 ◽  
Vol 36 (4) ◽  
pp. 405-415 ◽  
Author(s):  
Karol Zemko ◽  
Krzysztof Pabis ◽  
Jacek Siciński ◽  
Magdalena Błażewicz-Paszkowycz
Keyword(s):  
Brown Alga ◽  
Austral Summer ◽  
The Other ◽  
Total Density ◽  
Depth Range ◽  
Soft Bottom ◽  
Admiralty Bay

Abstract Fifteen species of isopods, representing 10 families, were recorded on holdfasts of the brown alga Himantothallus grandifolius. Material was collected in the 15–75 m depth range during the austral summer of 1979/80. The isopod community was dominated by Caecognathia antarctica (mean density 12.4 ± 13.1 ind./100 ml) followed by Cymodocella tubicauda (mean density 0.7 ± 2.1 ind./100 ml). Mean total density of isopods reached the value of 16.1 ± 14.0 ind./100 ml. The comparison with the other studies showed that holdfasts are inhabited by a distinctive isopod community that differs from the isopod fauna associated with soft bottom of Admiralty Bay.

scholarly journals Biological diversity in a changing world

2010 ◽  
Vol 365 (1558) ◽  
pp. 3593-3597 ◽  
Author(s):  
Anne E. Magurran ◽  
Maria Dornelas
Keyword(s):  
Climate Change ◽  
Temporal Variation ◽  
Habitat Loss ◽  
Environmental Conditions ◽  
Royal Society ◽  
Biological Diversity ◽  
Anthropogenic Activities ◽  
Evolutionary Processes ◽  
The World ◽  
Natural Change

From the pioneering explorations of Joseph Banks (later a President of the Royal Society), to the present day, a great deal has been learnt about the extent, distribution and stability of biological diversity in the world. We now know that diverse life can be found even in the most inhospitable places. We have also learned that biological diversity changes through time over both large and small temporal scales. These natural changes track environmental conditions, and reflect ecological and evolutionary processes. However, anthropogenic activities, including overexploitation, habitat loss and climate change, are currently causing profound transformations in ecosystems and unprecedented loss of biological diversity. This series of papers considers temporal variation in biological diversity, examines the extent of human-related change relative to underlying natural change and builds on these insights to develop tools and policies to help guide us towards a sustainable future.

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