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Mangroves are unique coastal ecosystems, which have many important ecological functions, as they are a reservoir of many marine species well adapted to saline conditions and are fundamental as sites of carbon storage. Although the microbial contribution to nutrient cycling in these ecosystems has been well recognized, there is a lack of information regarding the microbial composition and structure of different ecological types of mangrove forests. In this study, we characterized the microbial community (Bacteria and Archaea) in sediments associated with five ecological types of mangrove forests in a coastal lagoon dominated by Avicennia germinans and Rhizophora mangle, through 16S rRNA-V4 gene sequencing. Overall, Proteobacteria (51%), Chloroflexi (12%), Gemmatimonadetes (5%) and Planctomycetes (6%) were the most abundant bacterial phyla, while Thaumarchaeota (30%), Bathyarchaeota (21%) and Nanoarchaeaeota (18%) were the dominant archaeal phyla. The microbial composition associated with basin mangroves dominated by Avicennia germinans was significantly different from the other ecological types, which becomes relevant for restoration strategies.

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Abstract Polyphenolics from Rhizophora mangle (R. mangle) have shown wound healing and anti- inflammatory effects that may be potentiated by being associated with ascorbic acid, an important substance for collagen and elastin synthesis that plays a role in tissue repair. In our study, we aimed to formulate an association of R. mangle and ascorbic acid in hydrogels and evaluate the association's cytotoxic and immunomodulatory effects. In a pre-formulation study, three gelling polymers (i.e.xanthan gum, poloxamer and hydroxyethyl cellulose) were tested. The selected polymer (i.e. xanthan gum) was used to evaluate cytotoxic and immunomodulatory effects using flow cytometry. Xanthan gum (1.5%) had a homogeneous appearance, an orange colour, a smooth surface, intense brightness and the typical odour, as well as non-Newtonian pseudoplastic behaviour. With a pH of 5.0-5.3 and a non-cytotoxic profile, xanthan gum induced the proliferation and activation of CD4 +, CD8+ and NK T lymphocytes and the production of IL- 2, IL-4, IL-10, IL-17 and TNF-α cytokines in stimulated splenocytes. The results suggest that the association of R. mangle and ascorbic acid in 1.5% xanthan gum hydrogel may be promising in preparations for wound-healing processes

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Mangrove microbiomes play an essential role in the fate of mangroves in our changing planet, but the factors regulating the biogeographical distribution of mangrove microbial communities remain essentially vague. This paper contributes to our understanding of mangrove microbiomes distributed along three biogeographical provinces and ecoregions, covering the exuberant mangroves of Amazonia ecoregion (North Brazil Shelf) as well as mangroves located in the southern limit of distribution (Southeastern ecoregion, Warm Temperate Southwestern Atlantic) and mangroves localized on the drier semi-arid coast (Northeastern ecoregion, Tropical Southwestern Atlantic), two important ecotones where poleward and landward shifts, respectively, are expected to occur related to climate change. This study compared the microbiomes associated with the conspicuous red mangrove (Rhizophora mangle) root soils encompassing soil properties, latitudinal factors, and amplicon sequence variants of 105 samples. We demonstrated that, although the northern and southern sites are over 4,000 km apart, and despite R. mangle genetic divergences between north and south populations, their microbiomes resemble each other more than the northern and northeastern neighbors. In addition, the northeastern semi-arid microbiomes were more diverse and displayed a higher level of complexity than the northern and southern ones. This finding may reflect the endurance of the northeast microbial communities tailored to deal with the stressful conditions of semi-aridity and may play a role in the resistance and growing landward expansion observed in such mangroves. Minimum temperature, precipitation, organic carbon, and potential evapotranspiration were the main microbiota variation drivers and should be considered in mangrove conservation and recovery strategies in the Anthropocene. In the face of changes in climate, land cover, biodiversity, and chemical composition, the richness and complexity harbored by semi-arid mangrove microbiomes may hold the key to mangrove adaptability in our changing planet.

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Abstract Introduction: Knowledge of growth patterns, sex ratio, and sexual maturity are of importance to exploited populations. The land crab Cardisoma guanhumi is an artisanal and subsistence exploited species in Puerto Rico. However, the growth patterns and sexual maturity of the local populations are not known. Objectives: This study has a double objective: (1) to compare the size and sex structure between populations and (2) to model the relative growth of structures related to reproduction to estimate the average size of morphometric sexual maturity (MSM) for both males and females. Methods: A total of 2 849 specimens were captured from nine dispersed populations on the island between 2001 and 2020. Carapace width (CW) was measured as an estimator of the absolute size of all individuals, together with the propodus length (PL) in males and the abdomen width in females (AW). Differences in length structure between sexes and populations were tested by applying goodness-of-fit tests based on Kernel Density Estimators (KDE). The relative growth pattern was modeled adjusting a spline from which the maximum of its second derivative was calculated as an estimator of the MSM, and bootstrapping was used to generate confidence intervals. Results: Differences were found in size structures, between sexes, and between sites. Our estimates of morphometric sexual maturity resulted in a sexual maturity size for males between 57.9 and 79.0 mm CW, while in females, morphological maturity occurs between 43.8 to 51.5 mm CW. Conclusions: We found inter-population differences in body size that can be attributed to differences in the history of changes of land use and the exploitation biased towards larger individuals, though differences in recruitment should also be considered. Current regulations in Puerto Rico protect female crabs but not to larger male crabs. The regulation establishes that crabs smaller than 64 mm carapace width cannot be captured, leaving immature male crabs over 64 mm CW unprotected. We suggest considering different size limits depending on the sex of the crab. This will allow the full range of sizes where sexual maturity is reached to be protected, increasing the likelihood of the population's size to increase.

Resumen Introducción: El conocimiento de los patrones de crecimiento, la proporción de sexos y la madurez sexual son de suma importancia para las poblaciones explotadas. El cangrejo terrestre Cardisoma guanhumi es una especie explotada artesanalmente y para subsistencia en Puerto Rico. Sin embargo, se desconocen los patrones de crecimiento y la madurez sexual para la isla. Objetivos: Este estudio tiene un doble objetivo: (1) comparar el tamaño y la estructura sexual entre las poblaciones y (2) modelar el crecimiento relativo de estructuras relacionadas con la reproducción (propodo en machos y abdomen en hembras) para estimar el tamaño promedio de madurez sexual morfométrica (MSM). Métodos: Se capturaron un total de 2 849 especímenes de nueve poblaciones dispersas en la isla, entre 2001 y 2020. Se midió el ancho del caparazón (AC) como un estimador del tamaño absoluto de todos los individuos, junto con el largo de propodo en los machos y el ancho del abdomen en las hembras. Las diferencias en la estructura de tallas entre sexos y poblaciones se probaron aplicando la prueba de bondad de ajuste basado en estimaciones de densidad kernel (KDE). El patrón de crecimiento relativo se modeló ajustando un spline a partir del cual se calculó el máximo de su segunda derivada como estimador del MSM y se utilizó bootstrapping para generar intervalos de confianza. Resultados: Se encontraron diferencias en las estructuras de tallas, entre sexos y poblaciones. Nuestras estimaciones de madurez sexual morfométrica dieron como resultado un tamaño de madurez sexual para los machos entre 57.9 y 79.0 mm AC, mientras que, en las hembras, la madurez morfométrica se produce entre 43.8 y 51.5 mm AC. Conclusiones: La diferencia en el tamaño de la población se puede atribuir a las diferencias entre poblaciones en el cambio de uso de la tierra y la presión de explotación asociada con el sesgo hacia la captura de individuos más grandes o el reclutamiento. Las regulaciones actuales en Puerto Rico brindan protección a las hembras, pero no a los machos más grandes. El reglamento establece que no se pueden capturar cangrejos de menos de 64 mm de AC dejando desprotegidos los cangrejos machos inmaduros de más de 64 mm AC. Sugerimos considerar diferentes límites de tamaño según el sexo del cangrejo. Esto permitirá proteger un rango más amplio de tamaños donde se alcanza la madurez sexual, aumentando la probabilidad de un incremento en el tamaño de la población.

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La evaluación del impacto del petróleo en la interacción suelo-raíz de la planta de mangle blanco, Laguncularia racemosa, es básica para identificar los cambios en la actividad microbiana y en el potencial biotecnológico para la remediación de histosoles contaminados. El objetivo de la investigación fue evaluar la distribución espacial de los hidrocarburos totales del petróleo (HTP) en el suelo orgánico, la densidad poblacional de bacterias promotoras del crecimiento vegetal, así como la respiración microbiana en el rizoplano (RI) en la rizósfera (RZ) y en suelo no rizosférico (SNR) de L. racemosa. Una superficie de 8 000 m2 de un histosol afectado desde 1967 y 1968 se evaluó por derrame crónico de petróleo y lodos de perforación provenientes del pozo petrolero La Venta 248. Se seleccionaron 15 árboles de L. racemosa y se extrajeron muestras del RI, RZ y SNR. Los HTP se extrajeron en equipo soxhlet con diclorometano durante ocho horas y se cuantificaron por gravimetría. La cantidad promedio extraída de HTP permitió la diferenciación de cuatro suelos (S) en el área evaluada, con valor promedio para el S1 de 1 797 mg kg-1 (no contaminado para la normativa mexicana) y tres suelos contaminados: S2 con 3 294, S3: 5 249 y S4: 10 389 mg kg-1. Los resultados evidencian diferencias estadísticas (Duncan, P ≤ 0.05) entre medias de las variables evaluadas. La mayor acumulación de HTP fue 22 962 mg kg-1, se extrajo del SNR en el S4. Las mayores densidades de bacterias fijadoras de N, solubilizadoras de P, Azospirillum y Azotobacter fueron bioestimuladas por la presencia de niveles altos de HTP en el suelo, sin embargo la respiración microbiana fue inhibida. Los resultados sugieren que L. racemosa es sostenible en suelos con petróleo intemperizado, y es un bioestimulador de la actividad microbiana para la atenuación natural.

The evaluation of the impact of oil on the soil-root interaction of the white mangrove plant, Laguncularia racemosa is essential to identify changes in microbial activity and biotechnological potential for remediation contaminated histosols. The objective was to evaluate the spatial distribution of total petroleum hydrocarbons (THP) in organic soil, the population density of plant growth promoting bacteria, also in microbial respiration in the rhizoplane (RI), in the rhizosphere (RZ) and in non-rhizospheric soil (NRS) of L. racemosa. An area of 8 000 m2 of an affected histosol was evaluated, during 1967 and 1968, by chronic oil spill and drilling mud from the La Venta 248 oil well. Fifteen trees of this species were selected to obtain samples of the RI, RZ and NRS. The TPH were extracted in soxhlet with dichloromethane for eight hours and quantified by gravimetry. The average amount extracted from TPH allowed the differentiation of four soils (S) from the evaluated area, the average values were for S1: 1 797 mg kg-1 (not contaminated for Mexican regulations) and three contaminated soils, the values are S2: 3 294, S3: 5 249, and S4: 10 389 mg kg-1. The results show statistical differences (Duncan, P ≤ 0.05) between means of the evaluated variables. The greatest accumulation of TPH was 22 962 mg kg-1, it was extracted from the NRS in S4. The highest densities of N-fixing bacteria, P solubilizers, Azospirillum and Azotobacter were biostimulated by the presence of high levels of THP in the soil, however microbial respiration was inhibited. The results suggest that L. racemosa is sustainable in soils with weathering oil, and is a biostimulator of microbial activity for natural attenuation.

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The goal of this research was to generate networks of co-expressed genes to explore the genomic responses of Rhizophora mangle L. populations to contrasting environments and to use gene network analysis to investigate their capacity for adaptation in the face of historical and future perturbations and climatic changes. RNA sequencing data were generated for R. mangle samples collected under field conditions from contrasting climate zones in the equatorial and subtropical regions of Brazil. A gene co-expression network was constructed using Pearson's correlation coefficient, showing correlations among 78,364 transcriptionally coordinated genes. Each region exhibited two distinct network profiles; genes correlated with the oxidative stress response showed higher relative expression levels in subtropical samples than in equatorial samples, whereas genes correlated with the hyperosmotic salinity response, heat response and UV response had higher expression levels in the equatorial samples than in the subtropical samples. In total, 992 clusters had enriched ontology terms, which suggests that R. mangle is under higher stress in the equatorial region than in the subtropical region. Increased heat may thus pose a substantial risk to species diversity at the center of its distribution range in the Americas. This study, which was performed using trees in natural field conditions, allowed us to associate the specific responses of genes previously described in controlled environments with their responses to the local habitat where the species occurs. The study reveals the effects of contrasting environments on gene expression in R. mangle, shedding light on the different abiotic variables that may contribute to the genetic divergence previously described for the species through the use of simple sequence repeats (SSRs). These effects may result from two fundamental processes in evolution, namely, phenotypic plasticity and natural selection.

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Abstract Mangroves represent an environment of great heterogeneity and low diversity of plant species that have structural and physiological adaptations linked to a high salinity environment. Laguncularia racemosa is a typical tree species in mangroves and transitional zones. This study aimed to compare the wood anatomy of L. racemosa (Combretaceae) in two different forests (mangroves and transitional forests), which have different soil conditions. For this, we obtained wood and soil samples in March 2016. We analyzed soil nutritional contents in one 15 cm deep soil sample per forest type. In addition, we selected five mangrove trees in each formation for wood anatomy analysis and took one wood sample per individual, per area. We prepared histological slides and separated materials following standard methods for wood anatomy studies. Soil analysis showed that mangrove soils had higher phosphorus, potassium and calcium contents. The transitional soil had lower pore water salinity and soil pH, probably due to high aluminum levels. Anatomical attributes differed between different forest populations. In the different wood aspects evaluated, we obtained higher values in mangrove individuals when compared to the transitional forest population: vessel elements length (375.79 mm), tangential vessels diameter (75.85 mm), frequency of vessels (11.90 mm) and fiber length (889.89 mm). Moreover, parenchyma rays height was larger in the samples of the transitional forest (392.80 mm), while the mangrove population presented wider rays (29.38 mm). The structure of the secondary xylem in the studied species apparently responds to edaphic parameters and shows variations that allow it to adjust to the environmental conditions. The population of the transitional forest showed a secondary xylem that invests more in protection than the mangrove population. Rev. Biol. Trop. 66(2): 647-657. Epub 2018 June 01.

Resumen Los manglares representan un ambiente de gran heterogeneidad y baja diversidad de especies vegetales que tienen adaptaciones estructurales y fisiológicas ligadas a un ambiente de alta salinidad. Laguncularia racemosa es una especie de árbol típico en los manglares y en zonas de transición. El objetivo de este estudio fue comparar la anatomía de la madera de L. racemosa (Combretaceae) en dos bosques distintos (manglares y bosques de transición) que tienen diferentes condiciones edáficas. Para esto se obtuvieron muestras de madera y suelo en marzo 2016. Se analizaron los contenidos nutricionales de una muestra de suelo de 15 cm de espesor por tipo de bosque. Además, se seleccionaron cinco árboles de mangle en cada formación para el análisis de la anatomía de la madera y se tomó una muestra de cada individuo por área. Se prepararon láminas histológicas y se separaron los materiales siguiendo métodos convencionales para estudios de anatomía de la madera. El análisis del suelo mostró que en el manglar hay mayor contenido de fósforo, potasio y calcio. El suelo del bosque de transición tiene menor salinidad del agua capilar y pH del suelo, probablemente debido a los altos niveles de aluminio. Los atributos anatómicos difirieron entre las distintas poblaciones de bosque. En los distintos aspectos de la madera evaluados, se obtuvieron valores más altos en los individuos del manglar comparados con los de la población del bosque de transición: longitud de los elementos de los vasos (375.79 mm), diámetro de los vasos tangenciales (75.85 mm), frecuencia de vasos (11.90 mm) y longitud de la fibra (889.89 mm). Además, la altura de los rayos de parénquima fue mayor en las muestras del bosque de transición (392.80 mm) mientras que la población de manglar presentó rayos más anchos (29.38 mm). La estructura del xilema secundario en la especie estudiada aparentemente responde a los parámetros edáficos y muestra variaciones que le permiten adecuarse a las condiciones ambientales. La población del bosque de transición mostró un xilema secundario que invierte más en protección que la población del manglar.

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Resumen Los manglares se distribuyen a lo largo de gradientes topográficos en zonas costeras, donde las variaciones en salinidad y períodos de inundación influyen en la composición y productividad primaria. En este estudio se evaluaron los atributos estructurales y producción de hojarasca de los manglares de la Laguna Mecoacán, Golfo de México. En seis sitios de monitoreo se determinó durante la segunda semana de julio 2014, la composición florística, el diámetro a la altura del pecho (DAP), altura, densidad del mangle adulto, juveniles, reclutas y plántulas. Además, se calcularon el área basal, índice de valor de importancia (IVI) y cobertura. Se tomaron muestras mensuales (noviembre 2014 a octubre 2015) de producción de hojarasca de las especies de mangle mediante trampas de captura, mientras que los parámetros físico-químicos de agua superficial, intersticial y subterránea fueron determinados mediante piezómetros. Los sitios de estudio en la Laguna Mecoacan se clasificaron en dos tipos fisonómicos: Borde (Boca, Aspoquero, Arrastradero y Pajaral) y cuenca (Cerros y Mojarrero). La densidad promedio del manglar fue de 2 870 árboles. ha-1. El área basal más alta se encontró en Pajaral (41.7 m-2. ha). Avicennia germinans (L.) Stearn presentó los valores más altos de IVI en todos los sitios. Se registró una cobertura media de 17.5 m2. Las especies mostraron zonación con los niveles de salinidad de agua intersticial; A. germinans con mayor densidad en áreas de alta salinidad (hipersalinas), mientras Laguncularia racemosa (L.) Gaertn y Rhizophora mangle L. en áreas de menor salinidad. La producción de hojarasca fue de 5.15 ton. ha-1. año-1, mostró una correlación positiva con la precipitación y alta correlación negativa con los niveles de salinidad y ORP intersticial y subterránea. Los resultados indican que la variabilidad en la composición, la estructura y la producción de hojarasca en la Laguna Mecoacán está determinada localmente por la capacidad de adaptación a las condiciones ambientales (precipitación, salinidad, potencial redox) de las especies presentes. Se recomienda establecer los sitios como parcelas permanentes de monitoreo y estimar la biomasa en pie y debajo del suelo para entender mejor la dinámica de nutrientes como una de las principales fuentes de energía in situ y exportado a zonas adyacentes.

Abstract Mangrove forests are distributed along the topographical gradients of coastal areas, where variations in salinity and flooding influence the composition and primary production of these forests. This study evaluated the structural attributes and production of leaf litter of mangrove species in Mecoacán Lagoon. We established six monitoring sites and studied the floristic composition, diameter at breast height (DBH), and density of adult, juvenile and recruited trees, as well as seedling density; additionally, the basal area, importance value index (IVI), and coverage were also calculated. Monthly samples (from November 2014 to October 2015) of the leaf litter production of different mangrove species, were collected using litter traps, and the physicalchemical parameters of surface, interstitial, and subterranean water were determined using piezometers. The study sites were classified into two physiognomic types: fringe (Boca, Aspoquero, Arrastradero, and Pajaral) and basin (Cerros and Mojarrero). The average density of mangrove trees was 2 870 trees. ha-1. The highest basal area was found in Pajaral (41.7 m2. ha-1). Avicennia germinans presented the highest IVI value in all sites. An average coverage of 17.5 m2 was recorded. The species were zoned with respect to interstitial salinity levels. A. germinans had a greater density in areas with high salinity (hypersaline) and Laguncularia racemosa and Rhizophora mangle in areas of lower salinity. The leaf litter production was 5.15 ton. ha-1. year-1 and showed a positive correlation with rainfall and a highly negative correlation with salinity level as well as with interstitial and subterranean oxidation redox potential (ORP). The results indicated that variability in the composition, structure, and production of leaf litter in Laguna Mecoacán is locally determined by the species capacity to adapt to environmental conditions (rainfall, salinity, redox potential). Several recommendations include the establishment of the sites evaluated in this study, as permanent monitoring areas and to estimate the above and belowground biomass, in order to understand the nutrient dynamics, as mangroves provide sources of energy both in situ and that may be exported to neighboring areas.

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Resumen: Los propágulos de las especies de manglar presentan una particular estrategia de superviviencia y dispersión. Desafortunadamente algunos reportes han afirmado que los propágulos de Rhizophora mangle son frecuentemente atacados por coleópteros y lepidópteros antes y después de su período de dispersión. El escarabajo Coccotrypes rhizophorae es un parásito obligado que puede causar la mortalidad de propágulos y plántulas de R. mangle, moldeando la estructura de sus poblaciones. Debido a la importancia de esta especie de mangle, su sobrevivencia y el aumento del impacto humano en la zona, este trabajo evaluó la presencia de propágulos barrenados por C. rhizophorae en el manglar de Tumilco, en el estado de Veracruz, México. Para esto, se establecieron tres zonas de muestreo: 1) manglar de R. mangle, 2) zona más impactada al borde de un camino de terracería con R. mangle y A. germinans, y 3) borde con Typha latifolia y R. mangle; en cada área, tres parcelas aleatorias de 25x25 m fueron analizadas. Se registró el número de propágulos barrenados por zona cada 15 días durante un año de muestreo (n= 567) de enero a diciembre 2012. También observamos el área dañada del propágulo (basal, medio, apical) y los propágulos barrenados vivos y muertos por temporada y los resultados para diferentes temporadas en el área: lluvias, nortes y secas. Los insectos fueron identificados por un experto. Nuestros resultados muestran un incremento en el número de propágulos barrenados durante la temporada de secas, principalmente en la zona 2 y 3. La supervivencia de los propágulos barrenados fue mayor cuando se presentó la perforación en el área basal, y durante la temporada de secas y nortes. En particular, la zona de estudio 2 presentó mayor número de propágulos vivos cuando el daño se encontró en el área basal del propágulo. En las tres zonas hubo mayor mortalidad cuando el daño fue apical. La zona 1 y 3 presentaron mayor supervivencia de propágulos durante las secas, mientras que en la zona 2 la supervivencia fue mayor durante la temporada de lluvias y nortes. El número de propágulos disminuyó conforme los niveles de inundación aumentaron. Los resultados muestran que C. rhizophorae tiene una amplia distribución en el manglar de Tumilco, pero la mortalidad de los propágulos de R. mangle está infuenciada por el área dañada, por la temporada del año y por las características de la zona en donde se encuentre la infestación. Se requieren estudios para evaluar la forma en que la mortalidad de los propágulos afecta la estructura poblacional de R. mangle.

Abstract: Mangrove species propagules represent a particular survival and dispersal strategy. Unfortunately, some reports have stated that Rhizophora mangle propagules are frequently attacked by Coleoptera and Lepidoptera before and after their dispersion period. The beetle species Coccotrypes rhizophorae is an obligate parasite that can cause mortality in propagules and seedlings of R. mangle, and may modify the structure of its populations. Because of the importance on this mangrove species, survival and increasing human impacts in the area, this study evaluated the presence of propagules with C. rhizophorae boring evidence in the Tumilco mangrove, in Veracruz State, Mexico. For this, three sampling areas were established: 1) mangrove core of R. mangle, 2) most impacted edge of an unpaved road with R. mangle and A. germinans, and 3) edge with Typha latifolia and R. mangle; in each area, three 25x25 m random plots were analyzed. The number of bored propagules per site was recorded every 15 days over a sampling period of one year (n= 567) from January to December 2012. We also observed the damaged part of the propagule (basal, central, apical) and the number of live and dead bored propagules per season, and compared results for different seasons in the area: rainy, cold northerly fronts or "norte" and dry. Insects were identified by an expert. Our results showed that a higher number of bored propagules was observed during the dry season, mainly in zones 2 and 3. Survival of bored propagules was higher when the perforation occurred in the basal part of the plant, and during the dry and norte seasons. Study zone 2 in particular presented a higher number of live propagules when the damage occurred in the basal part of the propagule. In all three zones, mortality was higher when the damage was apical. Zones 1 and 3 presented higher propagule survival during the dry season, while survival in zone 2 was higher during the rainy and norte seasons. The number of propagules decreased with rising flooding levels. The results showed that C. rhizophorae has a wide distribution in the Tumilco mangrove, but the mortality of R. mangle propagules is influenced by the part of the propagule that suffers damage, as well as by the season of the year and the characteristics of the area in which the infestation occurs. Futher studies are required to evaluate the impact of propagule mortality on the population structure of R. mangle. Rev. Biol. Trop. 65 (3): 1120-1128. Epub 2017 September 01.

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ABSTRACT This work describes the isolation, by high-speed counter-current chromatography, of the diterpenes manool, jhanol and steviol and the benzaldehyde p-oxy-2-ethylhexyl benzaldehyde from the stilt roots hexane extract of the mangrove plant Rhizophora mangle L., Rhizophoraceae. For this, a non-aqueous biphasic solvent system composed of hexane–acetonitrile–methanol 1:1:0.5 (v/v/v) was applied. As far as we know, only steviol was previously isolated in Rhizophoraceae and this is the first time that p-oxy-2-ethylhexyl benzaldehyde is reported.

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Mangrove forests are highly productive and play a major role in global carbon cycling. Their carbon accumulation can be influenced through the consumption of nutrient-poor leaves and propagules by herbivore crabs. Anthropogenic nutrient input from sewage contamination is widespread in these often naturally nutrient-limited ecosystems. We hypothesised that sewage-mediated nutrient input to mangrove stands of Paranaguá Bay (southern Brazil), would alter the nutrient sources available for crabs, e.g. through microphytobenthos increase, and that this would reflect in their feeding behaviour. We predicted that propagules of Rhizophora mangle in contaminated stands would experience lower grazing pressure from their two main local consumers (Ucides cordatus and Goniopsis cruentata). We compared herbivory rates on R. mangle propagules in sewage contaminated and uncontaminated mangrove stands. We found that herbivory rates were significantly lower in contaminated than uncontaminated forests, but this pattern could not be clearly attributed to increased nutrient availability.

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ResumenLa distribución de carbono azul en los ecosistemas, entre los que se cuentan los manglares, es poco conocida en comparación con los grandes avances que existen para los ecosistemas forestales terrestres, a pesar de que su alta productividad y capacidad de almacenamiento de carbono es reconocida. Este estudio, tuvo por objetivo, analizar la biomasa aérea de las especies Rhizophora mangle y Avicennia germinans en el ecosistema de manglar localizado en el área marina protegida denominada Distrito de Manejo Integrado (DMI) Cispatá-Tinajones-La Balsa en el Caribe colombiano. Para ello, con la debida autorización oficial, se cosecharon 30 individuos de cada especie, con el fin de generar modelos alométricos que permitieran estimaciones de biomasa aérea con bajos niveles de incertidumbre. Los resultados indican que la biomasa aérea de los bosques de manglar del Caribe colombiano en el DMI, es de 129.69 ± 20.24 Mg/ha, es decir, que almacenan 64.85 ± 10.12 MgC/ ha. Teniendo en cuenta que el DMI presenta un área de 8 570.9 ha en bosques de manglar, se estima que el carbono total potencialmente almacenado por este ecosistema es de aproximadamente 555 795.93 MgC. Las ecuaciones generadas en este estudio se pueden considerar como una opción alternativa para la evaluación de las reservas de carbono en la biomasa aérea de los bosques de manglar en del Caribe colombiano, dado que otros modelos disponibles para la estimación de la biomasa aérea no discriminan a los bosques de manglar, a pesar de ser ecosistemas particulares. Los modelos pueden ser empleados como una opción para apoyar las estrategias de conservación de bosques y la reducción de emisiones. En general, el potencial de almacenamiento de carbono en los bosques de manglar del Caribe colombiano, es importante, y podría posesionar al país en la conservación de bosques y la reducción de emisiones a través de la conservación del carbono azul almacenado.

AbstractThe distribution of carbon in “Blue Carbon” ecosystems such as mangroves is little known, when compared with the highly known terrestrial forests, despite its particular and recognized high productivity and carbon storage capacity. The objective of this study was to analyze the above ground biomass (AGB) of the species Rhizophora mangle and Avicennia germinans from the Marine Protected Area of Distrito de Manejo Integrado (DMI), Cispatá-Tinajones-La Balsa, Caribbean Colombian coast. With official authorization, we harvested and studied 30 individuals of each species, and built allometric models in order to estimate AGB. Our AGB results indicated that the studied mangrove forests of the DMI Colombian Caribbean was of 129.69 ± 20.24 Mg/ha, equivalent to 64.85 ± 10.12 MgC/ha. The DMI has an area of 8 570.9 ha in mangrove forests, and we estimated that the total carbon potential stored was about 555 795.93 Mg C. The equations generated in this study can be considered as an alternative for the assessment of carbon stocks in AGB of mangrove forests in Colombia; as other available AGB allometric models do not discriminate mangrove forests, despite being particular ecosystems. They can be used for analysis at a more detailed scale and are considered useful to determine the carbon storage potential of mangrove forests, as a country alternative to support forest conservation and emission reduction strategies. In general, the potential of carbon storage from Colombian Caribbean mangrove forests is important and could promote the country leadership of the “blue carbon” stored. Rev. Biol. Trop. 64 (2): 913-926. Epub 2016 June 01.

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Mangrove forests have a simple architecture. They shelter a few number of arboreal species that grow in a saline environment subject to tidal activity. The research objective was to evaluate possible interactions between physical-chemical soil attributes and plant-leaf nutrient concentrations of different mangrove species. Different mangrove species growing in the same soil, and the same mangrove species growing in two different soil classes were evaluated as to their leaf nutrient concentration patterns. The study was carried out in mangrove areas of the State of Paraná, southern Brazil, in two distinct soil classes: HISTOSOL THIOMORPHIC Salic sodic and GLEYSOL THIOMORPHIC Salic sodic; and three different species: Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle. Two subareas were delimited within each area from which soil and leaf samples were collected. Samplings from five individuals of each dominant mangrove species were taken from the soil (0-10 cm deep) under each tree crown projection. The data was submitted to statistical analysis using a set of simple and multivariate analysis in order to determine possible differences among mangrove species leaf nutrient concentrations, and whether these differences might be correlated with the soil attributes or not. The results exposed that the nutritional state of the mangrove species is different and independent form the soil attributes in which they grow. Few correlations were found among leaf nutrient concentrations and soil attributes, suggesting differential selective nutrient uptake among species.

Los manglares son bosques de arquitectura simple que albergan pocas especies arbóreas, creciendo en un ambiente salino sometido a la influencia de las mareas. El objetivo de este trabajo fue evaluar las posibles interacciones entre las propiedades fisicoquímicas del suelo y la concentración de nutrientes en hojas de diferentes especies de mangle. Se investigó si las diferentes especies que se desarrollan en la misma clase de suelo tienen concentraciones de nutrientes foliares similares, y si las plantas de mangles de la misma especie que se desarrollan en diferentes tipos de suelos tienen concentraciones foliares similares. El estudio se desarrolló en manglares del Estado de Paraná, sur de Brasil, en dos tipos de suelos diferentes (HISTOSOL TIÓNICO Salino sódico y GLEYSOL TIÓNICO Salino sódico). Se analizaron tres especies vegetales diferentes (Avicennia schaueriana, Laguncularia racemosa y Rhizophora mangle). En cada área se delimitaron dos subáreas para recolectar el suelo y las hojas de cada una de las especies. Se tomaron cinco individuos de cada especie del dosel dominante para recoger hojas y muestras de suelo de 0-10 cm, en la proyección de la copa de los árboles seleccionados. Se realizaron análisis univariados y multivariados para probar si las especies de mangle tienen perfiles nutricionales diferentes, y si existe alguna correlación entre las propiedades del suelo con la composición química de las hojas. Los resultados mostraron que el estado nutricional de las especies de mangle es distinto e independiente de los atributos de los suelos en los que se encuentran. Las concentraciones de elementos en las hojas presentan poca correlación con los nutrientes del suelo, lo que sugiere que la absorción de nutrientes por las plantas es selectiva.

Manguezais são florestas de arquitetura simples, abrigando poucas espécies arbóreas, vegetando em ambiente salino e sujeito ao regime de marés. O objetivo desta pesquisa foi avaliar as possíveis interações entre os atributos físico-químicos do solo e a concentração de nutrientes nas folhas de diferentes espécies de mangue. Assim, foi investigado se as diferentes espécies que se desenvolvem sobre a mesma classe de solo apresentam concentrações de nutrientes foliares similares, e se plantas de mangue da mesma espécie que ocorrem sobre diferentes classes de solo apresentam concentrações de nutrientes foliares similares. O estudo foi desenvolvido em manguezais no Estado do Paraná, Sul do Brasil, em duas classes distintas de solo (ORGANOSSOLO TIOMÓRFICO Sálico sódico e GLEISSOLO TIOMÓRFICO Sálico sódico), e três espécies diferentes de plantas (Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle). Em cada área foram delimitadas duas subáreas para coleta de solo e folhas das espécies. Cinco indivíduos do dossel dominante de cada espécie para coleta de folhas, na projeção da copa das árvores, e amostras de solo de 0-10 cm foram selecionados. Para testar se espécies de mangue apresentam perfis nutricionais distintos e se há correlação entre os atributos do solo com a composição química foliar um conjunto de análises univariadas multivariadas foram realizadas. Os resultados demonstraram que o estado nutricional das plantas é distinto e individualizado, independente dos atributos do solo em que se encontram as espécies. As concentrações dos elementos nas folhas pouco se correlacionaram com os nutrientes do solo, sugerindo absorção seletiva dos nutrientes pelas plantas.

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ABSTRACT This study assessed the relation between Cu, Fe, Mn, and Zn in the soils of the mangroves of Antonina and Guaratuba, on the coastline of the State of Paraná, and in the leaf tissues of A. shauerianaR. mangle, and L. racemosa through the analysis of correlation levels between these two compartments. Leaf samples were collected for ten individuals of each species in a 1000 m2 area delimited in each mangrove. Soil samples from 0-10 cm depth were taken from under the crown projection area of the selected trees to be submitted to chemical analysis. In the soils, metallic micronutrients presented the following order: Fe > Mn > Zn > Cu. In the leaves, concentrations were species dependent. InA. shaueriana and R. mangle, the profile was Mn > Fe > Zn > Cu, while in L. racemosa, the sequence was: Fe > Mn > Zn > Cu. Correlation analyses revealed only four significant correlations for Mn, Zn, and Cu in the soil and plant compartments. These results suggested that significant correlations depended on abiotic factors, inhibition between the elements, and immobilization and/or adsorptions of these metals by the soil.

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Los conchales constituyen un rasgo muy característico de las adaptaciones humanas a los ambientes litorales. Analizar su composición y su variabilidad puede brindar indicios en cuanto a la subsistencia de antiguas poblaciones humanas, procesos de formación e información sobre cambios en el ambiente. Este estudio evaluó el uso de paleoconchas halladas en conchales para inferir las condiciones paleoambientales de un bosque de manglar. Datos de paleoconchas de conchales ubicados en Castilletes-Alta Guajira, Venezuela fueron datados en 3 580 ± 30 años A.P, se incluyeron datos de conchas actuales provenientes de la Laguna de Cocinetas (Castilletes) y de isla Maracas (Lago de Maracaibo). Se examinaron un total de 185 muestras con marcas de fijación de la raíz de mangle, paleoconchas (n = 109) y conchas actuales (n = 76) de C. rhizophorae. Posteriormente, se estimaron los diámetros de las paleoraíces y de las raíces actuales a través de un modelo geométrico utilizando la huella de fijación de la concha. Para validar el modelo se midieron directamente los diámetros de las raíces actuales. Adicionalmente se realizó un estudio fisionómico en los bosques de ambas localidades de estudio, para asociar la estructura del bosque, con el diámetro de las raíces y la información de las conchas. Los resultados mostraron que no hay diferencias significativas entre los diámetros de las raíces obtenidas por el modelo geométrico y los diámetros de las raíces medidas directamente (Castilletes P = 0.160854; Maracas P = 0.617271). Las mediciones de las conchas mostraron que las paleoconchas son más largas que las conchas modernas. Los diámetros de las paleoraíces no mostraron diferencias significativas con las raíces del bosque actual de Castilletes (zona expuesta) P = 0.303518, contrastando con los diámetros de las raíces de isla Maracas (zona protegida) (P = 0.017771). El estudio fisionómico mostro que el bosque actual de Castilletes tiene un DAP y una altura (11.10 y 4.90 m respectivamente) menor que Maracas (34.86 cm y 10.62 m), respondiendo a la exposición a los vientos. Se determinó que el paleobosque y el bosque actual de Castilletes tienen características similares asociadas con ambientes áridos, con fuerte exposición a los vientos. Se concluye que el análisis de las huellas de fijación de las paleoconchas es un método novedoso y de bajo costro que permite obtener información sobre el paleoambiente de los bosques de R. mangle.

Shell middens are a very characteristic feature of coastal human adaptations. Component and variability analysis offer clues to subsistence of ancient human populations, formation processes and information of environmental changes. In this study, we tested the use of paleoshells found in shell midden to infer paleoenviroment conditions of R. mangle forest. We presented data of paleoshells from shell middens, located on Castilletes-Alta Guajira, Venezuela, dated from 3 580 ± 30 años B.P years, and we included data of actual shells from mangrove forests located on Cocinetas laggon (Castilletes) and Maracas Island (Maracaibo lagoon). We examined 185 samples of fixing traces marked by mangrove roots on paleoshells (n = 109) and actual shells (n = 76) of C. rhizophorae. Subsequently, we estimated paleoroot and modern root diameter using a geometric model using shell's trace. To validate this model, we directly measured modern roots. Furthermore, a physiognomic study was made in both sites to associate mangrove forest with roots diameter and shells information. Results showed that there were no significant differences between estimated root diameter values obtained from traces of modern shells and the ones recorded by direct measurement of roots (Castilletes P = 0.160854; Maracas P = 0.617271); allowing the use of geometric model to obtain estimated values of paleoroots. Shell measurements showed that paleoshells were larger than modern shells. Paleoroot diameters showed no significant differences with modern Castilletes's mangrove roots (exposed zone) (P = 0.303518), contrasting with Maracas's roots (protected zone) (P = 0.017771). Physiognomic study showed that modern Castilletes forests had diameter at breast height (DBH) and tree height (11.10 m and 4.90 m, respectively) lower than Maracas (34.86 cm and 10.62 m), responding to the wind exposure and salinity. Diameters and quantity of roots per tree were higher in Castilletes (3.01 cm y 11 roots/tree) than Maracas (2.39 cm y 7 roots/tree). We determined that paleoforests and modern forests from Castilletes have similar characteristics associated to arid environment with stronger wind exposition. We concluded that paleoshells trace analysis is a low cost and novel method that allows obtaining information about paleoenvironment of R. mangle forests.

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BACKGROUND AND AIMS: Rhizophora species of mangroves have a conspicuous system of stilt-like roots (rhizophores) that grow from the main stem and resemble flying buttresses. As such, the development of rhizophores can be predicted to be important for the effective transmission of dynamic loads from the top of the tree to the ground, especially where the substrate is unstable, as is often the case in the habitats where Rhizophora species typically grow. This study tests the hypothesis that rhizophore architecture in R. mangle co-varies with their proximity to the main stem, and with stem size and crown position. METHODS: The allometry and wood mechanical properties of R. mangle (red mangrove) trees growing in a mangrove basin forest within a coastal lagoon in Mexico were compared with those of coexisting, non-buttressed mangrove trees of Avicennia germinans. The anatomy of rhizophores was related to mechanical stress due to crown orientation (static load) and to prevailing winds (dynamic load) at the study site. KEY RESULTS: Rhizophores buttressed between 10 and 33 % of tree height. There were significant and direct scaling relationships between the number, height and length of rhizophores vs. basal area, tree height and crown area. Wood mechanical resistance was significantly higher in the buttressed R. mangle (modulus of elasticity, MOE = 18·1 ± 2 GPa) than in A. germinans (MOE = 12·1 ± 0·5 GPa). Slenderness ratios (total height/stem diameter) were higher in R. mangle, but there were no interspecies differences in critical buckling height. When in proximity to the main stem, rhizophores had a lower length/height ratio, higher eccentricity and higher xylem/bark and pith proportions. However, there were no directional trends with regard to prevailing winds or tree leaning. CONCLUSIONS: In comparison with A. germinans, a tree species with wide girth and flare at the base, R. mangle supports a thinner stem of higher mechanical resistance that is stabilized by rhizophores resembling flying buttresses. This provides a unique strategy to increase tree slenderness and height in the typically unstable substrate on which the trees grow, at a site that is subject to frequent storms.

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Leaf litter represents a food source to many organisms that may directly contribute to organic matter decomposition. In addition, the physical presence of these vegetal detritus contributes for the modification of some environmental areas and produce microhabitats that may act as a refuge against predators and desiccation for many animals. The pulmonate gastropod Melampus coffeus (Linnaeus, 1758) (Ellobiidae) is a very common specie in Atlantic Coast mangrove forests and feeds on fallen mangrove leaves. It was hypothesized that the spatial distribution of Melampus coffeus is directly affected by mangrove leaf litter biomass deposition. Thus, this research aimed at evaluating the spatial distribution of these gastropods in relation to the biomass of mangrove leaf litter through a twelve-month period. The study area was established in the middle estuary of Pacoti River, state of Ceará, Brazil where two adjacent zones with different topographic profiles were determined. Samples of Melampus coffeus and leaf litter were collected monthly, throughout a year, from the mangrove ground surface. The results indicated that the presence of twigs in mangrove litter favor the occupation by smaller individuals of M. coffeus, probably because smaller individuals are more susceptible to predator attacks and desiccation than larger ones, and twigs and branches may provide a safe microhabitat

A serapilheira representa fonte de alimentos para diversos organismos que podem contribuir diretamente para a decomposição de matéria orgânica. A presença física desses detritos vegetais pode modificar áreas do ambiente e promover a formação de microhabitats, servindo de refúgio para diversos animais contra predadores e dessecação. O gastrópode Melampus coffeus (Linnaeus, 1758) (Ellobiidae) é comum em florestas de mangue na costa do Atlântico e se alimenta de folhas de mangue caídas. Nesse trabalho foi assumida a hipótese de que a distribuição espacial do Melampus coffeus é diretamente afetada pela deposição de serapilheira no manguezal. Objetivou-se avaliar a distribuição espacial desses gastrópodes em relação à serapilheira de mangue durante doze meses de coletas. A área de estudo foi estabelecida no médio estuário do rio Pacoti, Estado do Ceará, Brasil onde foram determinadas duas zonas de diferentes perfis topográficos. Amostras de Melampus coffeus e de serapilheira foram coletadas mensalmente. Os resultados indicaram que a presença de galhos na superfície do solo do manguezal favorece a ocupação do ambiente por indivíduos dessa espécie de molusco de menor tamanho, provavelmente porque indivíduos menores são mais suscetíveis ao ataque de predadores e à dessecação e a presença de galhos pode formar microhabitats mais seguros

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Leaf litter represents a food source to many organisms that may directly contribute to organic matter decomposition. In addition, the physical presence of these vegetal detritus contributes for the modification of some environmental areas and produce microhabitats that may act as a refuge against predators and desiccation for many animals. The pulmonate gastropod Melampus coffeus (Linnaeus, 1758) (Ellobiidae) is a very common specie in Atlantic Coast mangrove forests and feeds on fallen mangrove leaves. It was hypothesized that the spatial distribution of Melampus coffeus is directly affected by mangrove leaf litter biomass deposition. Thus, this research aimed at evaluating the spatial distribution of these gastropods in relation to the biomass of mangrove leaf litter through a twelve-month period. The study area was established in the middle estuary of Pacoti River, state of Ceará, Brazil where two adjacent zones with different topographic profiles were determined. Samples of Melampus coffeus and leaf litter were collected monthly, throughout a year, from the mangrove ground surface. The results indicated that the presence of twigs in mangrove litter favor the occupation by smaller individuals of M. coffeus, probably because smaller individuals are more susceptible to predator attacks and desiccation than larger ones, and twigs and branches may provide a safe microhabitat(AU)

A serapilheira representa fonte de alimentos para diversos organismos que podem contribuir diretamente para a decomposição de matéria orgânica. A presença física desses detritos vegetais pode modificar áreas do ambiente e promover a formação de microhabitats, servindo de refúgio para diversos animais contra predadores e dessecação. O gastrópode Melampus coffeus (Linnaeus, 1758) (Ellobiidae) é comum em florestas de mangue na costa do Atlântico e se alimenta de folhas de mangue caídas. Nesse trabalho foi assumida a hipótese de que a distribuição espacial do Melampus coffeus é diretamente afetada pela deposição de serapilheira no manguezal. Objetivou-se avaliar a distribuição espacial desses gastrópodes em relação à serapilheira de mangue durante doze meses de coletas. A área de estudo foi estabelecida no médio estuário do rio Pacoti, Estado do Ceará, Brasil onde foram determinadas duas zonas de diferentes perfis topográficos. Amostras de Melampus coffeus e de serapilheira foram coletadas mensalmente. Os resultados indicaram que a presença de galhos na superfície do solo do manguezal favorece a ocupação do ambiente por indivíduos dessa espécie de molusco de menor tamanho, provavelmente porque indivíduos menores são mais suscetíveis ao ataque de predadores e à dessecação e a presença de galhos pode formar microhabitats mais seguros(AU)

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The Rhizophora mangle roots form a complex ecosystem where a wide range of organisms are permanently established, reproduce, and find refuge. In this study, we assessed the diversity of bivalves and gastropods that inhabit red mangrove roots, in isla Larga, Mochima, Venezuela Sucre state. Bimonthly collections were made from January 2007 to May 2008, in four study areas denominated: South, North, East and West. In each area, five mangrove roots were sampled, and the specimens were obtained. We analyzed a total of 180 roots and a total of 35 bivalve species and 25 gastropod species were found. The most abundant bivalves were: Isognomon alatus, Isognomon bicolor, Ostrea equestris, Crassostrea rhizophorae and Brachidontes exustus; among gastropods, the most common where: Littorina angulifera, Cymatium pileare and Diodora cayenensis. The months with the highest abundances and number of individuals for both groups were January and July 2007, and March 2008. The mangrove ecosystem in isla Larga, presented a number of individuals and species higher than those reported for other regions in Venezuela and the Caribbean. Rev. Biol. Trop. 62 (2): 551-565. Epub 2014 June 01.

Las raíces del mangle rojo forman un complejo ecosistema donde se reproducen, refugian y establecen de manera permanente una gran diversidad de organismos. En este estudio, se evaluó la diversidad de bivalvos y gasterópodos que habitan las raíces del mangle rojo Rhizophora mangle, en isla Larga, Bahía de Mochima, estado Sucre Venezuela. Se realizaron recolectas bimensuales desde enero 2007 hasta mayo 2008, en cuatro zonas de estudio denominadas: zona sur, norte, este y oeste. En cada zona se muestrearon cinco raíces de mangle, de donde se obtuvieron los especímenes. Se analizaron un total 180 raíces y se contabilizaron 35 especies de bivalvos y 25 de gasterópodos. Los bivalvos más abundantes fueron: Isognomon alatus, Isognomon bicolor, Ostrea equestris, Crassostrea rhizophorae y Brachidontes exustus, mientras que los gasterópodos más frecuentes: Littorina angulifera, Cymatium pileare y Diodora cayenensis. Los meses donde se observaron las mayores abundancias de especies y número de individuos fueron enero y julio 2007 y marzo 2008. El ecosistema de manglar en isla Larga, presentó un número de individuos y especies superior al reportado en otros trabajos realizados en Venezuela y otras regiones del Caribe.

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Hurricanes severely damaged a mangrove forest in a UNESCO biosphere reserve in the U.S. Virgin Islands. The system has yet to recover and when alternative habitats have been destroyed, it is shown that juvenile fishes will hyperutilize seagrass beds at densities significantly greater than in areas that maintain functioning mangroves. Despite over a decade of recovery time, the affected mangrove system remains inhospitable to juvenile fishes.

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