Marine invertebrates associated with rhodoliths/maërl beds from northeast Brazil (State of Paraíba).

BACKGROUND: This study investigates the marine macroinvertebrate fauna of rhodolith beds (non-geniculated red corallinaceaous algae) in northeast Brazilian. A total of 57 species were identified, belonging to six phyla (Platyhelminthes, Annelida, Sipuncula, Mollusca, Arthropoda and Echinodermata), of which 50 are considered here as new records for the Paraíba State. Annelids (Class Polychaeta) were the most representative taxa in Miramar and Seixas Beaches, while molluscs were dominant in Maceió Beach. NEW INFORMATION: This is the first study that includes an identification key, diagnostic features and distribution patterns worldwide and local (including new records) of the marine invertebrate fauna associated with rhodolith beds in northeast Brazil (State of Paraíba). Sampling events were performed in 2018, at low tide in the intertidal to shallow subtidal zones (1.5 and 4.0 m depth), in Miramar, Seixas and Maceió Beaches. A total of 17 species were found for the first time on Seixas Beach, as well as all identified species for Miramar and Maceió. This study tries to contribute to the knowledge of marine invertebrates in northeast Brazilian shallow habitats, providing a baseline for future environmental studies.

Integrated analyses of fecal indicator bacteria, microbial source tracking markers, and pathogens for Southeast Asian beach water quality assessment.

The degradation of coastal water quality from fecal pollution poses a health risk to visitors at recreational beaches. Fecal indicator bacteria (FIB) are a proxy for fecal pollution; however the accuracy of their representation of fecal pollution health risks at recreational beaches impacted by non-point sources is disputed due to non-human derivation. This study aimed to investigate the relationship between FIB and a range of culturable and molecular-based microbial source tracking (MST) markers and pathogenic bacteria, and physicochemical parameters and rainfall. Forty-two marine water samples were collected from seven sampling stations during six events at two tourist beaches in Thailand. Both beaches were contaminated with fecal pollution as evident from the GenBac3 marker at 88%-100% detection and up to 8.71 log10 copies/100 mL. The human-specific MST marker human polyomaviruses JC and BK (HPyVs) at up to 4.33 log10 copies/100 mL with 92%-94% positive detection indicated that human sewage was likely the main contamination source. CrAssphage showed lower frequencies and concentrations; its correlations with the FIB group (i.e., total coliforms, fecal coliforms, and enterococci) and GenBac3 diminished its use as a human-specific MST marker for coastal water. Human-specific culturable AIM06 and SR14 bacteriophages and general fecal indicator coliphages also showed less sensitivity than the human-specific molecular assays. The applicability of the GenBac3 endpoint PCR assay as a lower-cost prescreening step prior to the GenBac3 qPCR assay was supported by its 100% positive predictive value, but its limited negative predictive values required subsequent qPCR confirmation. Human enteric adenovirus and Vibrio cholerae were not found in any of the samples. The HPyVs related to Vibrio parahaemolyticus, Vibrio vulnificus, and 5-d rainfall records, all of which were more prevalent and concentrated during the wet season. More monitoring is therefore recommended during wet periods. Temporal differences but no spatial differences were observed, suggesting the need for a sentinel site at each beach for routine monitoring. The exceedance of FIB water quality standards did not indicate increased prevalence or concentrations of the HPyVs or Vibrio spp. pathogen group, so the utility of FIB as an indicator of health risks at tropical beaches maybe challenged. Accurate assessment of fecal pollution by incorporating MST markers could lead to developing a more effective water quality monitoring plan to better protect human health risks in tropical recreational beaches.

Distribución espacio-temporal de la meiofauna béntica en cuatro playas del Literal Norte de la Habana / Temporal spatial distribution of benthic meiofauna in four beaches of the northern Havana shore

The temporal-spatial distribution of benthic meiofauna was evaluated in four beaches at the north coast of Havana, Cuba, from March 2003 to February 2004. We studied two urban beaches (Santa Fe and La Concha) and two tourist beaches (Mar Azul and Canasi). Monthly meiofauna samplings were taken by scuba-diving using with a syringe (inner diameter 2.5 cm), and physico-chemical parameters (grain size, interstitial salinity and water column salinity were recorded with standard equipment). Statistical analysis (MDS and ANOSIM) were performed. Depth and biotope kind were the same in the four beaches. Highest densities were obtained in Santa Fe (7,133.48 ind/10 cm2) while the lowest mean densities were found in Canasí (892.12 ind/10 cm2). We recorded 13 taxa; the dominant organisms in Santa Fe and Mar Azul were free-living marine nematodes. Copepods were the dominant organisms in La Concha and Canasí.

Con el objetivo de evaluar la distribución espacio-temporal de la meiofauna béntica en la zona sublitoral del norte de la Habana, se realizaron muestreos mensuales en cuatro playas, dos al W de la ciudad (Santa Fe y La Concha) y dos al E (Mar Azul y Canasí), desde marzo del 2003 hasta febrero del 2004. Se mantuvo constante la profundidad de muestreo, biotopo y tipo de sedimento, observándose la relación con la salinidad en la columna de agua e intersticial. Para determinar la afinidad entre estaciones se realizó un análisis MDS y para establecer diferencias significativas entre éstas a nivel espacial ó temporal se realizó un análisis de similitud ANOSIM. Las densidades medias más altas se obtuvieron en Santa Fe (7 133. 48 ind/10 cm2) y las más bajas en Canasí (892.12 ind/10 cm2). Se registraron un total de 13 táxones en todas las áreas estudiadas, siendo los nemátodos de vida libre los organismos dominantes en las estaciones de Santa Fe y Mar Azul, y los copépodos los dominantes en La Concha y Canasí. Se detectaron dos picos de abundancia para los nemátodos y los copépodos durante el período de estudio, así como diferencias significativas entre las estaciones muestreadas, agrupándose así: Santa Fe - La Concha y Mar Azul - Canasí.