Eco-Physiological Responses of Avicennia marina (Forssk.) Vierh. to Trace Metals Pollution via Intensifying Antioxidant and Secondary Metabolite Contents.

Mangrove is one of the most precious ecosystems with the greatest losses due to climate change, human activities, and pollution. The objective of this study is to assess the accumulation and distribution of some trace metals (Cu, Cd, Ni, Pb, and Zn) in sediments and Avicennia marina roots and leaves and to discuss the antioxidant potential of A. marina under metallic pollution stress. Sediments, leaf, and root samples of A. marina were collected from five sites along the Red Sea Coast of Egypt. Several ecological pollution indices, including the geo accumulation index (Igeo), contamination factor (CF), pollution load index (PLI), bioconcentration factor (BCF), and translocation factor (TF), were used to assess the pollution load. Cu, Cd, Ni, Pb, and Zn average concentrations in sediments were 167.4, 0.75, 110.65, 39.79, and 220 µg g-1, respectively, and the average values of these metals in A. marina roots were 44.9, 0.5, 87.96, 39.02, and 54.68 µg g-1, respectively, while in leaves their concentration were 50.46, 0.5572, 88.24, 40.08, and 56.08 µg g-1, respectively. The values of the Igeo, CF, and PLI index indicated that location 1 and 5 are moderate-to-heavily contaminated sites. On the other hand, leaves and roots of A. marina grown in polluted locations 1 and 5 showed high accumulation of malondialdehyde (MDA), low chlorophyll a and chlorophyll b contents concomitant with a decrease in total soluble sugars. High total antioxidant capacity was associated with a significant increase in activity levels of antioxidant enzymes (Catalase, Polyphenol oxidase, Polyphenol peroxidase, and Ascorbic acid oxidase), accumulation of secondary metabolites (total phenols, flavonoids, and tannins), and proline and carotenoids content increase. Overall, the present study suggests that the mangrove habitat of the Egyptian Red Sea coast is under the stress of anthropogenic activities, which necessitates a conservation plan to avoid further contamination and protect the unique biota of this distinctive habitat.

Novel Gene Clusters for Natural Product Synthesis Are Abundant in the Mangrove Swamp Microbiome.

Natural microbial communities produce a diverse array of secondary metabolites with ecologically and biotechnologically relevant activities. Some of them have been used clinically as drugs, and their production pathways have been identified in a few culturable microorganisms. However, since the vast majority of microorganisms in nature have not been cultured, identifying the synthetic pathways of these metabolites and tracking their hosts remain a challenge. The microbial biosynthetic potential of mangrove swamps remains largely unknown. Here, we examined the diversity and novelty of biosynthetic gene clusters in dominant microbial populations in mangrove wetlands by mining 809 newly reconstructed draft genomes and probing the activities and products of these clusters by using metatranscriptomic and metabolomic techniques. A total of 3,740 biosynthetic gene clusters were identified from these genomes, including 1,065 polyketide and nonribosomal peptide gene clusters, 86% of which showed no similarity to known clusters in the Minimum Information about a Biosynthetic Gene Cluster (MIBiG) repository. Of these gene clusters, 59% were harbored by new species or lineages of Desulfobacterota-related phyla and Chloroflexota, whose members are highly abundant in mangrove wetlands and for which few synthetic natural products have been reported. Metatranscriptomics revealed that most of the identified gene clusters were active in field and microcosm samples. Untargeted metabolomics was also used to identify metabolites from the sediment enrichments, and 98% of the mass spectra generated were unrecognizable, further supporting the novelty of these biosynthetic gene clusters. Our study taps into a corner of the microbial metabolite reservoir in mangrove swamps, providing clues for the discovery of new compounds with valuable activities. IMPORTANCE At present, the majority of known clinical drugs originated from cultivated species of a few bacterial lineages. It is vital for the development of new pharmaceuticals to explore the biosynthetic potential of naturally uncultivable microorganisms using new techniques. Based on the large numbers of genomes reconstructed from mangrove wetlands, we identified abundant and diverse biosynthetic gene clusters in previously unsuspected phylogenetic groups. These gene clusters exhibited a variety of organizational architectures, especially for nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS), implying the presence of new compounds with valuable activities in the mangrove swamp microbiome.

Estimating the Effects of a Hurricane on Carbon Storage in Mangrove Wetlands in Southwest Florida.

Tropical and subtropical mangrove swamps, under normal conditions, can sequester large amounts of carbon in their soils but as coastal wetlands, they are prone to hurricane disturbances. This study adds to the understanding of carbon storage capabilities of mangrove wetlands and explores how these capacities might change within the scope of a changing storm climate. In September 2017, Naples Bay, FL, USA (28°5' N, 81°47' W) encountered a direct hit from hurricane Irma, a Saffir-Simpson category 3 storm. By comparing carbon storage, forest community structure, and aboveground productivity collected in 2013 and in 2019, we estimated the effects of hurricane Irma on mangrove functions. Aboveground biomass increased during the study period at a rate of approximately 0.72 kg m-2 yr-1, significantly less than the average found in undisturbed mangrove forests. Soil carbon storage decreased at all study sites. On average, 2.7 kg-C m-2 was lost in the top 20 cm between sample collections. Carbon loss in belowground pools could point to a feedback of mangrove swamps on climate change as they lose their ability to store carbon and increase net atmospheric carbon. Nevertheless, mangrove swamps remain resilient to tropical storms in the long term and can recover their carbon storage capacity in the years following a storm.

Myxomycetes from mangroves: species occurring in the state of Maranhão, northeastern Brazil

Abstract Mangrove swamps and forests cover over 137,000 km2 distributed latitudinally among subtropical zones, 7% of which are in Brazil, with a greater density in the countrys northernmost region. Considering that the community of Myxomycetes recorded for this environment is hardly known, three areas located in the state of Maranhão were investigated. Two field trips were conducted, one at the beginning of the rainy season and another during the dry season. In each area, two plots (125 m2) equidistant 100 m apart from each other were surveyed. In these areas, standing dead tree trunks and dead branches still attached to the mother plant that were above the tideline, were examined. On these same occasions, samples of the aerial litter and from the cortex of living trees (Rhizophora) were collected for the preparation of moist chambers cultures. Twenty-one specimens were obtained from field and moist chambers, belonging to 11 species, distributed in nine genera and five families. Seven species are new records from Maranhão. There was a predominance of r-strategist (73%) over K-strategist (27%) species. Cribraria violacea, Comatricha tenerrima, Echinostelium minutum, and Fuligo septica are new worldwide records from mangrove environments, and Oligonema flavidum is reported for the first time from Brazil.

Resumo Os manguezais ocupam mais de 137.000 km2, distribuídos latitudinalmente entre as zonas subtropicais e 7% encontra-se no Brasil, com maior densidade entre os estados do Pará e Maranhão, na região norte do país. Considerando que a comunidade de mixomicetos registrada para este ambiente é pouco conhecida, três áreas localizadas no estado do Maranhão foram investigadas. Duas excursões foram realizadas, uma no início da estação chuvosa e outra na estiagem. Em cada área, foram georeferenciadas e exploradas duas parcelas (125 m2) equidistantes 100 m uma da outra foram avaliadas. Nestas, foram explorados troncos mortos em pé e galhos mortos ainda presos à planta-mãe, acima da linha da maré. Nas mesmas ocasiões foram coletadas amostras de folhedo aéreo e córtex de árvores vivas (Rhizophora) para montagem de câmaras-úmidas. Foram obtidos 21 espécimes de campo e câmara-úmida, pertencentes a 11 espécies, distribuídas em nove gêneros e cinco famílias. Sete espécies são novos registros para o Maranhão. Predominaram espécies r-estrategistas (73%), e 27% K-estrategistas. Cribraria violacea, Comatricha tenerrima, Echinostelium minutum e Fuligo septica são novos registros para o ambiente de manguezal, e Oligonema flavidum é registrada pela primeira vez no Brasil.

Myxomycetes from mangroves: species occurring in the state of Maranhão, northeastern Brazil / Myxomycetes em manguezais: espécies ocorrentes no estado do Maranhão, nordeste do Brasil

Abstract Mangrove swamps and forests cover over 137,000 km2 distributed latitudinally among subtropical zones, 7% of which are in Brazil, with a greater density in the country’s northernmost region. Considering that the community of Myxomycetes recorded for this environment is hardly known, three areas located in the state of Maranhão were investigated. Two field trips were conducted, one at the beginning of the rainy season and another during the dry season. In each area, two plots (125 m2) equidistant 100 m apart from each other were surveyed. In these areas, standing dead tree trunks and dead branches still attached to the mother plant that were above the tideline, were examined. On these same occasions, samples of the aerial litter and from the cortex of living trees (Rhizophora) were collected for the preparation of moist chambers cultures. Twenty-one specimens were obtained from field and moist chambers, belonging to 11 species, distributed in nine genera and five families. Seven species are new records from Maranhão. There was a predominance of r-strategist (73%) over K-strategist (27%) species. Cribraria violacea, Comatricha tenerrima, Echinostelium minutum, and Fuligo septica are new worldwide records from mangrove environments, and Oligonema flavidum is reported for the first time from Brazil.

Resumo Os manguezais ocupam mais de 137.000 km2, distribuídos latitudinalmente entre as zonas subtropicais e 7% encontra-se no Brasil, com maior densidade entre os estados do Pará e Maranhão, na região norte do país. Considerando que a comunidade de mixomicetos registrada para este ambiente é pouco conhecida, três áreas localizadas no estado do Maranhão foram investigadas. Duas excursões foram realizadas, uma no início da estação chuvosa e outra na estiagem. Em cada área, foram georeferenciadas e exploradas duas parcelas (125 m2) equidistantes 100 m uma da outra foram avaliadas. Nestas, foram explorados troncos mortos em pé e galhos mortos ainda presos à planta-mãe, acima da linha da maré. Nas mesmas ocasiões foram coletadas amostras de folhedo aéreo e córtex de árvores vivas (Rhizophora) para montagem de câmaras-úmidas. Foram obtidos 21 espécimes de campo e câmara-úmida, pertencentes a 11 espécies, distribuídas em nove gêneros e cinco famílias. Sete espécies são novos registros para o Maranhão. Predominaram espécies r-estrategistas (73%), e 27% K-estrategistas. Cribraria violacea, Comatricha tenerrima, Echinostelium minutum e Fuligo septica são novos registros para o ambiente de manguezal, e Oligonema flavidum é registrada pela primeira vez no Brasil.

Avaliação da qualidade dos sedimentos da orla de Santos empregando-se ensaios de toxicidade e caracterização da estrutura da comunidade macrobentônica / Sediment quality assessment of Santos shoreline trough toxicity assays and characterization of macrobenthic community structure

O presente trabalho avaliou a qualidade do sedimento da orla de Santos por meio da realização de ensaios de toxicidade e caracterização da estrutura da comunidade de macrofauna bentônica em 7 pontos localizados nas desembocaduras dos canais de drenagem fluvial nas praias de Santos-SP. Foram realizadas duas campanhas (Verão-Fevereiro de 2008 e Inverno--Julho de 2008). Os ensaios de toxicidade com ouriço-do-mar Lytechinus variegatus foram realizados nos tratamentos elutriato e interface sedimento-água, conforme ABNT NBR 15350/2006. A macrofauna bentônica foi identificada em Mollusca, Crustacea e Polychaeta, e calculadas a densidade média (inds/0,026m²) e dominância de Polychaeta. Nas campanhas de Verão e Inverno, o tratamento interface sedimento-água apresentou toxicidade em todos os pontos, enquanto o tratamento elutriato somente apresentou toxicidade nos pontos 6 e 7. A dominância de polychaeta correlacionou-se negativamente (r = -0,56) com a granulometria e positivamente (r = 0,93) com a matéria orgânica da campanha de inverno, sendo algumas espécies bioindicadoras de ambientes poluídos e anóxicos.

This study evaluated the toxicity of the sediment on 7 points located in front of drainage canals river on the beaches of Santos-SP, together with the characterization of the community structure of benthic macrofauna. Were performed campaign summer (February 2008) and the campaign winter (July 2008). The toxicity tests with sea-urchin Lytechinus variegatus treatments were performed in elutriate and sediment-water interface, as ABNT NBR 15350/2006. The benthic macrofauna wasidentified as Mollusca, Crustacea and Polychaeta, and it was calculated mean density (ind/0,026m²) and Polychaeta dominance. In campaigns for summer and winter treatment sediment-water interface showed toxicity at all points, while the treatment elutriate showed toxicity at points 6 and 7. Polychaeta dominance was negatively correlated (r = -0,56) with granulometry and positively correlated with organic matter for the winter campaign, being some of these species indicators of polluted and anoxic environments.

Laboratory scale bioremediation of petroleum hydrocarbon – polluted mangrove swamps in the Niger Delta using cow dung

Aims: The aim of the study was to carry-out laboratory–scale bioremediation of petroleum hydrocarbon polluted mangrove swamps using cow dung as source of limiting of nutrients. Methodology and Results: In a 70 days study, the cow dung treated polluted soil had its total culturable hydrocarbon utilising bacterial/fungi, heterotrophic bacterial and fungal counts increased progressively from the 28th day to the 70th day. The control set- up showed very slight increment in its microbial growth. Alkaline pH was observed in all the treatments and control during the study period. The conductivity values of cow dung decreased progressively. In the cow dung treatment option, the nitrate concentration decreased from 35.44 mg/kg to 14.28 mg/kg. Phosphate concentration of cow dung option decreased from 25.41 mg/kg to 9.31mg/kg. The control had the nitrate decreased from 8.42 mg/kg to 6.98 mg/kg. Percentage total organic carbon (% TOC) in the cow dung option decreased from 4.06% to 0.96%. Control experiment had the % TOC decreased from 3.32% to 2.99%. Studies using Gas chromatographic analyses showed that 0%, 49.88%, and 69.85% of Total petroleum hydrocarbon (TPH) were lost at zero hour, 28th day and 70th day respectively in the cow dung option. In addition, in the control experimental set-up, 0%, 7.14% and 13.42% of TPH were lost at zero hour, 28th day and 70th day respectively. Conclusion, significance and impact of study: The use of organic nutrient sources such as cow dung has shown good promises in bioremediation of crude oil impacted Mangrove Swamps in the Niger Delta. The next line of action is to transfer the technology to pilot scale study.

Contribuição ao Estudo da Planície Litorânea do Estado do Paraná

The present paper contains an approach to systematize the study of the State of Paraná coastal plains, in the southern part of Brazil. It contains in general some geographical and geological data, documented by maps, sketches and photographs. In the initial stage the coastal plain represents a marine ingression, caused by faulting. This ingression penetrated the valleys of a not yet determinated geological landscape. Ended the movement of deeping by faulting begins the epirogenic ascension and building of the barriers and beach ridges. An intensive sedimentation caused the lagoons and bays obstruction. This work refers mainly to t33 he sedimentary formations and the coastal plains is classified in the following way for the study in consideration to the morphology and origin: Marine sedimentation - shore, barrier and beach ridge; Intermediary sedimentation - mangrove swamps, mud and sand banks and mangrovito; Continental sedimentation - dunes and terrestrial alluvion. There are also presented some data about the rocky coast and vegetation.