Size-fractionated chitin contribution to seston, with linkages to the copepod acartia

The main purpose of the present work was to determine chitin from experimental size-fractioned incubations of the copepod Acartia tonsa, considered one of the primary sources of chitin in the Bahía Blanca Estuary. Sampling was performed during the austral warm season at one station in 2014 and 2015. Field-collected females (200 individuals) and males (100 individuals) were incubated in 8 L containers in the laboratory simulating in situ environmental conditions of temperature and salinity for 72 hours. Chitin content was measured in different size fractions (20-60, 60-135 and ≥135 μm). Particulate organic matter and dry weight were also determined in the different size fractions. Highly agglutinated debris, pellets, and natural food (diatoms and tintinnids) were observed in the 20-60 μm size fraction, with a maximum of 0.68±0.21mg L-1 chitin, and the highest contribution of chitin to POC (34.62±18.50 %). Eggs, nauplii and natural food (diatoms and tintinnids) were observed in the 60-135 μm size fraction, with a maximum of 0.20±0.12 mg L-1 chitin and a contribution to POC of 9.80±5.00 %. Acartia adults and their exuviae were observed in the ≥135 μm size fraction, with a maximum concentration of chitin of 0.67±0.40, and a maximum contribution of chitin to POC TS of 30.47±27.23 %. Differences were detected between the different fractions in chitin, POC and DW, indicating that the 20-60 and ≥135 µm size fractions were both an important contribution of chitin in the experiment. Our results suggest that pellets, carcasses and exuviae along with natural food and organic aggregates were the main source of chitin in this system.Fil: Biancalana, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Berasategui, Anabela Anhi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

Variations of mesozooplankton composition in a eutrophicated semi-enclosed system (Encerrada Bay, Tierra del Fuego, Argentina)

The aim of the present study was to analyze EB mesozooplankton composition in the light of the physico-chemical parameters of the water column. Particular attention was paid to the presence of opportunistic species which adapt favourably to EB´s environmental conditions.Fil: Biancalana, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Torres, Américo Iadran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Harpacticoida (Copepoda) in the plankton of Ushuaia and Golondrina Bays, Beagle Channel, Argentina

Harpacticoid copepods form a diverse and abundant group of the meiofauna in marine benthic habitats. Moreover, harpacticoids are frequently found in planktonic samples particularly in shallow and algae-covered coastal waters. Despite their high abundance, little is known about their taxonomy and importance as a component of the food web in the Southern bays of Argentina. Mesozooplankton samples and environmental data were obtained seasonally from Ushuaia and Golondrina Bays (August 2004 to June 2005) and analyzed for the composition and abundance of harpacticoid copepods. Remarkable seasonal changes in the harpacticoid communities were observed. In Ushuaia Bay, nitrogenated nutrients, chlorophyll a, salinity, and temperature were the prevailing environmental parameters that influenced the harpacticoid community, giving rise to different harpacticoid assemblages. The results highlight the importance of the community of Harpacticoida in both bays and provide background data for further studies on zooplankton communities and monitoring programs in marine systems.Fil: Biancalana, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Veit Köhler, G.. German Centre for Integrative Biodiversity Research; AlemaniaFil: Fricke, Anna Lena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Leibniz Centre for Tropical Marine Research; AlemaniaFil: Berasategui, Anabela Anhi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

Chitin determination on marine seston in a shallow temperate estuary (Argentina)

A quitina é um dos biopolímeros mais abundantes no planeta. A quitina foi quantificada em frações do seston, com a finalidade de obter a primeira caracterização deste polímero no Estuário de Bahía Blanca. A amostragem foi realizada durante o inverno e o verão em dois locais: em um canal de maré não impactado (Bahía del Medio, BM) e em um setor de descarga de esgoto (Canal Vieja, CV). Os maiores valores de quitina foram observados na fração seston ; 500 µM) não excederam ~ 1% de quitina total. A maior concentração de quitina no seston < 20 µM sugere que essa fração é um grande reservatório deste biopolímero, contribuindo para a matéria orgânica para os microorganismos na cadeia alimentar do Estuário de Bahía Blanca. Este é o primeiro estudo sobre as possíveis fontes de quitina em ecossistemas marinhos na Argentina.Chitin is one of the most abundant biopolymers in the planet. Chitin was quantified in seston fractions in order to obtain the first characterization of this polymer in the Bahía Blanca Estuary. Sampling was conducted at two sites: a non- impacted tidal channel -Bahía del Medio (BM)- and a sewage discharge sector -Canal Vieja (CV)-, during winter and summer. The highest values of chitin were observed in the seston fraction ;500 µm) did not exceed ~1% of total chitin.. The higher concentration of chitin in sesto

Interaction between heavy metals and chitin present in the seston of the Bahía Blanca estuary

Se midieron las concentraciones de metales pesados y quitina en el seston del Estuario de Bahía Blanca (EBB). Se determinó la concentración de carbono orgánico particulado (COP) y material particulado en suspensión (MPS). El Cd, Cu y Zn presentaron mayores concentraciones en la fracción mayor de seston (≥ 200 μm) y Pb, Mn, Ni, Cr y Fe en la fracción menor de éste (≤ 20 μm). La mayor concentración de quitina se detectó en la fracción ≤ 20 μm, junto con altos valores COP y MPS. Se detectaron diferencias entre las distintas fracciones en todos los metales pesados, COP y MPS, no así en la quitina. Correlaciones significativas se hallaron entre metales, COP y MPS, y este último con quitina. Entre los metales pesados y la quitina se halló una posible interacción, destacándose la quitina como posible agente de retención de metales pesados en el seston del EBB.Centro de Investigaciones Geológica

Interaction between heavy metals and chitin present in the seston of the Bahía Blanca estuary

Se midieron las concentraciones de metales pesados y quitina en el seston del Estuario de Bahía Blanca (EBB). Se determinó la concentración de carbono orgánico particulado (COP) y material particulado en suspensión (MPS). El Cd, Cu y Zn presentaron mayores concentraciones en la fracción mayor de seston (≥ 200 μm) y Pb, Mn, Ni, Cr y Fe en la fracción menor de éste (≤ 20 μm). La mayor concentración de quitina se detectó en la fracción ≤ 20 μm, junto con altos valores COP y MPS. Se detectaron diferencias entre las distintas fracciones en todos los metales pesados, COP y MPS, no así en la quitina. Correlaciones significativas se hallaron entre metales, COP y MPS, y este último con quitina. Entre los metales pesados y la quitina se halló una posible interacción, destacándose la quitina como posible agente de retención de metales pesados en el seston del EBB.Centro de Investigaciones Geológica

Mesozooplankton composition and spatial distribution, Nuevo Gulf, Patagonia, Argentina

The composition and spatial distribution of mesozooplankton of Nuevo Gulf, Argentina, were analyzed from surface samples taken on July, 1997. A total of 32 taxa were recorded. The highest abundances were found close to Nueva Bay, which is located nearby a growing urban population, whereas the lowest values were detected in the center of the gulf. Holoplankton dominated at all stations and evidenced a homogeneous spatial distribution. Meroplankton showed a more heterogeneous pattern. Ctenocalanus vanus was the most abundant taxon followed by Paracalanus parvus. Gastropoda veligers dominated the meroplanktonic fraction. Our results showed that the spatial distribution of the mesozooplankton seemed to be mainly influenced by the dominant hydrological circulation pattern of the region. This research establishes the first scientific basis for further studies in zooplankton communities of this important gulf, closely related to a natural protected worldwide known area declared a world heritage site by UNESCO

Interaction between heavy metals and chitin present in the seston of the Bahía Blanca estuary

Se midieron las concentraciones de metales pesados y quitina en el seston del Estuario de Bahía Blanca (EBB). Se determinó la concentración de carbono orgánico particulado (COP) y material particulado en suspensión (MPS). El Cd, Cu y Zn presentaron mayores concentraciones en la fracción mayor de seston (≥ 200 μm) y Pb, Mn, Ni, Cr y Fe en la fracción menor de éste (≤ 20 μm). La mayor concentración de quitina se detectó en la fracción ≤ 20 μm, junto con altos valores COP y MPS. Se detectaron diferencias entre las distintas fracciones en todos los metales pesados, COP y MPS, no así en la quitina. Correlaciones significativas se hallaron entre metales, COP y MPS, y este último con quitina. Entre los metales pesados y la quitina se halló una posible interacción, destacándose la quitina como posible agente de retención de metales pesados en el seston del EBB.Centro de Investigaciones Geológica

Plastisphere on microplastics: In situ assays in an estuarine environment

In this study, the influence of the plastisphere on metals accumulation and weathering processes of polystyrene (PSMPs) and nylon microplastics (NyMPs) in polluted waters during a 129 day-assay were studied. MPs were characterized through scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), X-ray diffraction (XRD), attenuated total reflectance Fourier transformed infrared (ATR-FTIR) spectroscopy, contact angle, and thermogravimetric analysis (TGA). Also Cr, Mn, Zn, Cd, Pb, and Cu in the plastisphere on MPs were analyzed during the assay. Potentially pathogenic Vibrio, Escherichia coli, and Pseudomonas spp. were abundant in both MPs. Ascomycota fungi (Phona s.l., Alternaria sp., Penicillium sp., and Cladosporium sp.), and yeast, were also identified. NyMPs and PSMPs exhibited a decrease in the contact angle and increased their weights. SEM/EDX showed weathering signs, like surface cracks and pits, and leaching TiO2 pigments from NyMPs after 42 days. XRD displayed a notorious decrease in NyMPs crystallinity, which could alter its interaction with external contaminants. Heavy metal accumulation on the plastisphere formed on each type of MPs increased over the exposure time. After 129 days of immersion, metals concentrations in the plastisphere on MPs were in the following order Cr ˃ Mn ˃ Zn ˃ Cu ˃ Pb ˃ Cd, demonstrating how the biofilm facilitates metal mobilization. The results of this study lead to a better understanding of the impact of marine plastic debris as vectors of pathogens and heavy metals in coastal environments.Fil: Forero Lopez, Ana Deisy. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Brugnoni, Lorena Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Abasto, Benjamín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Rimondino, Guido Noé. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Lassalle, Verónica Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Ardusso, Maialen Gisel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Nazzarro, Marcelo Sandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Martinez, Ana María. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Spetter, Carla Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Biancalana, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Fernandez Severini, Melisa Daiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin

The ocean sampling day consortium.

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world's oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits