Occurrence and Health Risk Assessment of Heavy Metals in the Blue Land Crab (Cardisoma guanhumi) from a Tropical Mangrove Swamp.

Coastal ecosystems in the Caribbean are vulnerable to pollution from land-based activities with possible impacts to human health. Ten heavy metals in the blue land crab, Cardisoma guanhumi, harvested from the Caroni Swamp, Trinidad, were investigated in the wet and dry seasons. Metal concentrations (µg g-1 dry weight) in crab tissue were: As (0.15-6.46), Ba (0.69-19.64), Cd (< 0.001-3.36), Cr (0.63-3.64), Cu (26.64-120.31), Hg (0.09-1.83), Ni (1.21-9.33), Se (0.19-1.55), V (0.16-0.69) and Zn (121.06-494.3). There were seasonal differences in the concentration of some heavy metals and, Cu and Zn exceeded the local maximum permissible levels for fish and shellfish at several sites in either one or both seasons. Health risk assessment based on estimated daily intake, target hazard quotient and hazard index revealed that Cardisoma guanhumi harvested from the Caroni Swamp, does not pose a health risk to consumers.

The Sea Swallowed our Houses and Rice Fields: The Vulnerability to Climate Change of Coastal People in Guinea-Bissau, West Africa.

Guinea-Bissau remains among the African countries most vulnerable to climate change due to its flat topography and large meandering coastal area invaded by the tides.We present a case study of the island-village of Djobel, showing the dramatic consequences of socio-environmental change. The inhabitants' attempts to mitigate the impact of extreme weather events and sea-level rise and adapt to the new circumstances have been hampered by the seizure of their upland territory by a neighboring village. In the context of a disconnect between state and society, Djobel's inhabitants want the state to guarantee their rights to productive land, water, and safe housing conditions. This case shows the need for legal protection of the rights of poor, marginalized, and underrepresented populations at risk of becoming climate refugees in the fragile context of politically unstable, failed, and often authoritarian states.

Oil spill model development and application for predicting vertical transport of non-volatile aliphatic hydrocarbons in stagnant water: Case of Nigerian Niger Delta mangrove swamps.

Oil spills have become a major source of pollution. In some cases, the impacted environment is self-cleansed by waves. Turbulent environments have enjoyed research attention with models available. However, it is different for stagnant water in sections of Nigerian Niger Delta mangrove swamp. This paper reports on developing mathematical models for monitoring transport of non-volatile aliphatic hydrocarbons by water and sediments using equations of transport and mass transfer. The models were validated using results from a simulated stagnant water mangrove swamp polluted with crude oil. From the result, non-volatile aliphatic hydrocarbons transported through water at 0.25 m and 1 m for month 1 is 335.75 µg/l and 0.062 µg/l for experiment and 360.0 µg/l and 0.181 µg/l for model respectively. While month 5, was 1505.37 µg/l and 15.78 µg/l for experiment and 1300.77 µg/l and 28.94 µg/l for model respectively. These and others reported show that the models developed can adequately predict the transport of non-volatile aliphatics.

Density and diversity of filamentous fungi in the water and sediment of Araçá bay in São Sebastião, São Paulo, Brazil / Densidade e diversidade de fungos filamentosos na água e sedimento da Baía do Araçá, São Sebastião (SP), Brasil

Abstract Araçá Bay, located in the city of São Sebastião, São Paulo, Brazil, is a protected area of substantial complexity. It represents the last remaining mangrove swamp preserve between the cities of Bertioga and Ubatuba on the northern coast of São Paulo State. This mangrove swamp has specific physical and chemical properties, and it shelters a wide variety of life, including fungi. These microorganisms are present in a variety of species with different morphophysiological features, and they have the ability to produce enzymes of biotechnological importance. The goal of this study was to quantify, isolate, and identify filamentous fungi in water and sediment samples from the Araçá Bay mangrove swamp in São Sebastião. Two samplings were performed in the summer and two were performed in the winter. The samples were collected from intertidal zones, and dissolved oxygen (DO), temperature, salinity, and pH were measured in situ. The spread plate technique was used to inoculate the samples collected on plates with a potato dextrose agar (PDA) medium. A total of 208 colonies (68 from water samples and 140 from sediment samples) were isolated, and they were identified based on their morphological characteristics. Filamentous fungus density was higher in the sediment than in the water, and the samplings performed in the winter revealed a higher density than those performed in the summer. Though some of the environmental parameters were not ideal for fungal development, a high quantity of growth was nevertheless observed. When the isolated colonies were analyzed, the greatest diversity and species richness were found in the summer samples. The genera identified in all of the samples were Aspergillus, Penicillium, Cladosporium, and Fusarium. The pathogenic species found from these genera were Aspergillus fumigatus, A. terreus, Penicillium citrinum, and P. chrysogenum. These species are also able to produce enzymes that offer a variety of applications. The fungal community described herein represents the diversity found in this mangrove swamp during the period studied. Many of the fungus species found are pathogenic and may be useful due to their ability to produce specific enzymes applicable in the biotechnological and pharmaceutical industries.

Resumo A Baía do Araçá, localizada no município de São Sebastião (SP), é uma região protegida, de grande complexidade, mantendo o último remanescente preservado de manguezal entre Bertioga e Ubatuba, litoral Norte do Estado de São Paulo. Manguezal caracteriza-se com propriedades físico-químicas específicas e abriga grande diversidade de seres vivos, entre eles os fungos. Estes microrganismos apresentam grande variedade de espécies e diferentes características morfofisiológicas com capacidade de produzir algumas enzimas de importância biotecnológica. Este trabalho teve como objetivo quantificar, isolar e identificar fungos filamentosos em amostras de água e de sedimento do manguezal da Baía do Araçá, São Sebastião, (SP). Foram realizadas 2 coletas no verão e 2 no inverno na região entremarés, medidos "in situ" os parâmetros oxigênio dissolvido (OD), temperatura, salinidade e pH. Utilizou-se a Técnica "Spread Plate" para inocular os materiais coletados, em placas com meio Potato Dextrose Agar (PDA). Foram isoladas 208 colônias (68 das amostras de água e 140 das amostras de sedimento) e identificadas pelas características morfofisiológicas. As densidades de fungos filamentosos foram maiores no sedimento em relação à água e nas coletas realizadas no inverno demonstraram maiores densidades do que no verão. Apesar de alguns parâmetros ambientais não se apresentarem ideais para o desenvolvimento dos fungos, observou-se alta quantidade de crescimento nas amostragens. Analisando as colônias isoladas, a maior diversidade e riqueza foram observadas na amostragem coletado no verão. Foram observados os gêneros Aspergillus sp, Penicillium sp, Cladosporium sp e Fusarium sp em todas as amostragens, dos quais as espécies Aspergillus fumigatus, A. terreus, Penicillium citrinum e P. chrysogenum identificados neste trabalho são considerados patogênicos mas também são espécies capazes de produzir enzimas aplicáveis em diversas atividades. A comunidade fúngica descrita apresenta a diversidade encontrada neste manguezal em relação à variedade ambiental no período estudado, sendo que muitos apresentam patogenicidade e podem ser uteis pela sua capacidade de produzir enzimas específicas aplicáveis nos estudos biotecnológicos e farmacêuticos.

Ecological risk assessments and context-dependence analysis of heavy metal contamination in the sediments of mangrove swamp in Leizhou Peninsula, China.

Sediments in eight types of mangroves were sampled in the Leizhou Peninsula. Heavy metals were analyzed to investigate the effects on metal distribution of mangrove communities, to evaluate contamination levels, identify sources and relationships between the two. Results showed that mangrove communities have effects on most heavy metal distributions in sediments, especially in the sediment with shrub communities of Aegiceras corniculatum where the contents of many metals are highest. As, Cr and Ni were identified as metal pollutants of primary concern, while Cd was of no concern. Zn, Pb, As mainly originated from anthropogenic source while the other metals are geogenic. Heavy metal distributions were affected by the independent and joint effects of landscape and sediment context; landscape context explains more variations in heavy metals than does sediment physicochemical variables. Total sulfur, total phosphorus and total potassium in sediment, and the existence of paddy field and forest land within 2000m around the sampling sites are significant variables also.

Distribución espacial de las especies de mangle y su asociación con los tipos de sedimentos del sustrato, en el sector estuarino del Humedal Nacional Térraba-Sierpe, Costa Rica / Spatial distribution of mangrove species and their association with the substrate sediment types, estuarine sector Térraba-Sierpe National Wetlands, Costa Rica

Resumen Se describe la composición florística del manglar y la distribución espacial de las principales especies de mangle y otras especies vegetales asociadas, presentes en el sector estuarino del Humedal Nacional Térraba-Sierpe, mediante el levantamiento de campo de 1 127 puntos y 77 parcelas de muestreo de 60x10m. Por otra parte, se explora la relación entre el tipo de sedimento subyacente y las especies de mangle establecidas sobre éste. Los resultados de composición, estructura y distribución de la vegetación del HNTS, muestran que el manglar exhibe un modelo o zonación, consistente en la variación desde la costa al continente y de las márgenes de los canales o esteros al interior de las llanuras de marea, de las distintas especies. Rhizophora racemosa y Pelliciera rhizophorae son las especies que muestran una mayor distribución espacial o distribución continua, con los mayores valores de abundancia (45.44% y el 39.92%, respectivamente), frecuencia (88.31% y 74.03%) y área de manglar (7 670.73ha y 5 824.94ha). Se confirmó la dependencia entre la presencia de especies de mangle y el tipo de sedimento del sustrato, de modo que las especies Avicennia spp. y L. racemosa tienden a distribuirse en los sustratos arenosos con mayor facilidad que las otras especies cuya distribución es más homogénea sobre los sustratos lodosos.

Abstract This research describes the floristic composition and spatial distribution of the main mangroves species and other associated flora present in the estuarine sector of Térraba-Sierpe National Wetland, Costa Rican Pacific. Field survey consists of 1 127 points and 77 sampling points of 60x10m. Results of composition, structure and distribution of mangrove in HNTS exhibits a pattern or species zonation. We found variation from the coast to mainland and from the fringe or estuaries to the interior tidal flats. The species Rhizophora racemosa and Pelliciera rhizophorae showed greater spatial and continuous distribution, with the highest values of abundance (45.44% and 39.92% respectively), frequency (88.31% and 74.03%) and mangrove area (7 670.73ha and 5 824.94ha). The mangrove fern, Acrostichum aureum, was the third most important species, meanwhile, Avicennia spp., Rhizophora mangle y Laguncularia racemosa showed a segregated distribution or a tendency to local conglomeration, Talipariti tiliaceum var. pernambucense, Mora oleifera y Conocarpus erectus were found in very localized areas and other species were considered companions with low contribution to the total coverage. The dependence was confirmed between the presence of mangrove species and sediment type substrate. The species Avicennia spp. and L. racemosa tend to be distributed in sandy substrates more easily than the other species whose distribution is more homogeneous on muddy substrates. Rev. Biol. Trop. 63 (Suppl. 1): 47-60. Epub 2015 April 01.

In vitro antimicrobial activity and characterization of mangrove isolates of streptomycetes effective against bacteria and fungi of nosocomial origin

The study aimed at determining the in vitro antimicrobial activity of alkaliphilic and halotolerant actinomycetes isolated from a mangrove ecosystem and identification of a potent strain. Twenty five isolates of actinomycetes were isolated from the sediment samples of Valapattanam mangrove swamp in Kerala, India. Antimicrobial activity of four selected actinomycete isolates was determined against bacterial and fungal pathogens of nosocomial origin by agar well diffusion method. Molecular characterization of the potent isolate was performed by 16S rDNA sequencing. Isolate no I-1 significantly inhibited Staphylococcus aureus ATCC 25923 (12 mm), S. aureus (15±0.05 mm), S. citreus (20±0.5 mm), Bacillus cereus (17±0.2 mm) and Serratia marcescens (12 mm). It also demonstrated effective antifungal action against Penicillium sp. (12±0.2 mm), Candida albicans (20±0.5 mm), C. parapsilosis (12 mm) and Cryptococcus neoformans (12 mm). Morphological study revealed that all the isolated actinomycetes belonged to the genus Streptomyces. Based on 16S rDNA sequence data, the selected isolate I-1 was shown to be closely related to Streptomyces xiamenensis. The results revealed that the mangrove ecosystem of Valapattanam harboured a rich consortium of many potent actinomycetes, which could synthesize novel bioactive compounds of pharmacological significance.