Seasonal Responses of Phyloplankton Productivity to Water-Quality Variations in a Coastal Karst Ecosystem of the Yucatan Peninsula

Dzilam Lagoon (DL) is a shallow, semienclosed, coastal ecosystem located on the north coast of the Yucatan Peninsula. With 9.4 km3 surface area, this system is influenced by groundwater (GD) supply and inorganic nutrients drained from the nearby mangrove. DL is highly preserved and provides a unique site to address the seasonal responses of phytoplankton production to environmental variability in a karstic and pristine scenario. Twelve monthly sampling trips were undertaken during Sep. 1998–Aug. 1999 to record in situ physicochemical parameters and collect water for inorganic nutrients, chlorophyll a (Chl a), and phytoplankton production at seven stations plus one GD. Highest Chl a concentrations were determined at the innermost points of the lagoon, whereas primary production peaked at brackish zones. The average net primary production in DL (80 g C m-3 yr-1) is lower than that reported for other coastal lagoons of the Yucatan Peninsula. Differences in the physical setting and disturbance extent between DL and those ecosystems are discussed as the context underlying their distinct production levels

Evaluating the capacity of species distribution modeling to predict the geographic distribution of the mangrove community in Mexico

This work is licensed under a Creative Commons Attribution 4.0 International License.Mangroves are highly productive ecosystems that provide important environmental services, but have been impacted massively in recent years by human activities. Studies of mangroves have focused on their ecology and function at local or landscape scales, but little has been done to understand their broader distributional patterns or the environmental factors that determine those distributions. Species distribution models (SDMs), have been used to estimate potential distributions of hundreds of species, yet no SDM studies to date have assessed mangrove community distributions in Mexico (the country with the fourth largest extent of this ecosystem). We used maximum entropy approaches to model environmental suitability for mangrove species distributions in the country, and to identify the environmental factors most important in determining those distributions. We also evaluated whether this modeling approach is adequate to estimate mangrove distribution as a community across Mexico. Best models were selected based on statistical significance (AUC ratio), predictive performance (omission error of 5%), and model complexity (Akaike criterion); after this evaluation, only one model per species met the three evaluation criteria. Environmental variable sets that included distance to coast yielded significantly better models; variables with strongest contributions included elevation, temperature of the coldest month, and organic carbon content of soil. Based on our results, we conclude that SDMs can be used to map mangrove communities in Mexico, but that results can be improved at local scales with inclusion of local variables (salinity, hydroperiod and microtopography), field validations, and remote sensing data.National Council for Science and Technology in Mexico (N°275430

Eutrofización costera en la Península de Yucatán

28 páginas, 12 figuras, 2 tablas.-- Artículo incluido en el Cap.IV: Manejo de la Zona Costera del Golfo de México.El financiamiento ha provenido del CONACYT (PO20COOR; 4147PT; 32356T; SISIERRA-2000-07-06-15), CONABIO (B019; M011; S004) y CINVESTAV-IPN Unidad Merida.Peer reviewe

Nueve nuevos registros de diatomeas bentónicas de los géneros Climaconeis, Cocconeis, Licmophora, Talaroneis, Oestrupia, Petroneis y Synedrosphenia en la costa norte de la Península de Yucatán, México

The ecology and floristics of the marine benthic diatoms are barely studied in Mexico. For the Yucatán Península, there are practically no studies dealing with these topics. The objective of this study is to present new records of benthic diatoms and their distribution in the northern coast of the Yucatán Península; descriptions based on light and electron microscopy are also provided. In order to achieve this, we examined phytoplankton samples from various localities and from Thalassia testudinum blades on Dzilam de Bravo. With the exception of Synedrosphenia cuneata and Cocconeis maxima the remainder species were found both on phytoplankton and T. testudinum samples, thus suggesting that re-suspension processes of benthic diatoms are occurring in the area. The most abundant species was Climaconeis aff. coxii. The number of new records from a few samples emphasizes the need to continue and intensify the study of benthic diatoms in the Yucatán Península.En México la florística y ecología de las diatomeas bentónicas marinas han sido escasamente estudiadas. Para la Península de Yucatán prácticamente no existen trabajos que aborden dichos tópicos. El objetivo de este estudio es dar a conocer nuevos registros de diatomeas bentónicas y su distribución en la costa norte de la Península de Yucatán, proporcionando sus descripciones con base en observaciones de microscopía óptica y electrónica. Para ello, se revisaron muestras de fitoplancton costero obtenidas en diez localidades, así como de diatomeas epífitas sobre Thalassia testudinum en Dzilam de Bravo. Con excepción de Synedrosphenia cuneata y Cocconeis maxima, que solo aparecieron sobre T. testudinum, las especies se encontraron tanto sobre T. testudinum como en la columna de agua. Esto sugiere que ocurren procesos de resuspensión de diatomeas béntonicas en el área. La especie con mayor abundancia fue Climaconeis aff. coxii. La cantidad de nuevos registros en este trabajo a partir de un reducido número de muestras, enfatiza la necesidad de continuar e intensificar el estudio de las diatomeas bentónicas de la Península de Yucatán

Methane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico

Porewater profiles in sediment cores from mangrove-dominated coastal lagoons (Celestún and Chelem) on the Yucatán Peninsula, Mexico, reveal the widespread coexistence of dissolved methane and sulfate. This observation is interesting since dissolved methane in porewaters is typically oxidized anaerobically by sulfate. To explain the observations we used a numerical transport-reaction model that was constrained by the field observations. The model suggests that methane in the upper sediments is produced in the sulfate reduction zone at rates ranging between 0.012 and 31 mmolm-2 d-1, concurrent with sulfate reduction rates between 1.1 and 24 mmol SO2- 4 m-2 d-1. These processes are supported by high organic matter content in the sediment and the use of non-competitive substrates by methanogenic microorganisms. Indeed sediment slurry incubation experiments show that non-competitive substrates such as trimethylamine (TMA) and methanol can be utilized for microbial methanogenesis at the study sites. The model also indicates that a significant fraction of methane is transported to the sulfate reduction zone from deeper zones within the sedimentary column by rising bubbles and gas dissolution. The shallow depths of methane production and the fast rising methane gas bubbles reduce the likelihood for oxidation, thereby allowing a large fraction of the methane formed in the sediments to escape to the overlying water column

Durinskia yucatanensis sp. nov. (Peridiniales: Kryptoperidiniaceae), una nueva especie de dinoflagelado planctónico, y su hábitat en aguas costeras de Yucatán, Golfo de México

Background: In the coastal waters of the northern Yucatan Peninsula, in the southeastern Gulf of Mexico, numerous pelagic algal blooms have been recorded in the 21st century. In August 2010, an unknown small-sized Peridiniales species caused an intense bloom in the Sisal marina. In subsequent years, it was occasionally found at other sites along the Yucatan coast. Goals: The main objective of the present study was to name this dinoflagellate as a new species and determine its ecological preferences. Methods: Phytoplankton blooms were monitored from August 2011 to September 2014. Fixed cells of the studied species were examined in a JEOL JSM-7600F scanning electron microscope. Its ecological preferences were evaluated using multivariate permutational analysis and generalized additive models (GAM). Results: The name Durinskia yucatanensis (Dinophyceae: Peridiniales) with the thecal plate formula Po X 4’ 2a 6” 5c 4s(?) 5”’ 2”” is proposed for a previously recorded Kryptoperidiniaceae species from the northern Yucatan coastal waters. Dissolved inorganic nitrogen positively correlated with cell abundances for both the exposed coast and marinas, especially in July-August, characterized by high water temperature (31-32 °C). Chlorophyll-a was the only parameter that presented significant spatio-temporal variability among years, months, and sampling sites. The GAM showed that temperature and salinity can predict changes in abundance in different study zones (exposed coast and marinas). The highest values were observed in the Progreso-Chicxulub area along the exposed coast in 2011 and only at Dzilam in marinas during all studied years. Conclusions: The species appears to prefer eutrophic conditions typical for marinas along the northern coast of Yucatan.Antecedentes: En las aguas costeras del norte de la península de Yucatán, en el sureste del Golfo de México, numerosos florecimientos pelágicos de microalgas se han registrado en el siglo 21. En agosto de 2010, una especie pequeña y desconocida de Peridiniales causó un florecimiento intenso en el puerto de abrigo de Sisal. En los años siguientes, se encontró ocasionalmente en otros sitios a lo largo de la costa de Yucatán. Objetivo: Nombrar a este dinoflagelado como una especie nueva para la ciencia y determinar sus preferencias ecológicas. Métodos: Los florecimientos de fitoplancton fueron monitoreados desde agosto de 2011 hasta septiembre de 2014. Las células se examinaron en un microscopio electrónico de barrido JEOL JSM-7600F. Sus preferencias ecológicas se evaluaron mediante análisis permutacional multivariante y modelos aditivos generalizados (GAM). Resultados: El nombre Durinskia yucatanensis (Dinophyceae: Peridiniales), cuya fórmula de placa tecal Po X 4’ 2a 6” 5c 4s(?) 5”’ 2””, se propone para una especie de Kryptoperidiniaceae previamente registrada de las aguas costeras del norte de Yucatán. El nitrógeno inorgánico disuelto se correlacionó positivamente con la abundancia de células, tanto para la costa expuesta como para los puertos deportivos, especialmente en julio-agosto, caracterizados por una alta temperatura del agua (31-32 °C). La clorofila-a fue el único parámetro que presentó variabilidad espacio-temporal significativa entre años, meses y sitios de muestreo. Los GAM demostraron que la temperatura y la salinidad pueden predecir cambios en la abundancia en diferentes zonas de estudio (costa expuesta y puertos deportivos). Los valores más altos se observaron en el área de Progreso-Chicxulub a lo largo de la costa expuesta en 2011 y solo en Dzilam en marinas durante todos los años estudiados. Conclusiones: La especie parece preferir las condiciones eutróficas típicas de los puertos deportivos a lo largo de la costa norte de Yucatán

Carbon Stocks of Tropical Coastal Wetlands within the Karstic Landscape of the Mexican Caribbean

Coastal wetlands can have exceptionally large carbon (C) stocks and their protection and restoration would constitute an effective mitigation strategy to climate change. Inclusion of coastal ecosystems in mitigation strategies requires quantification of carbon stocks in order to calculate emissions or sequestration through time. In this study, we quantified the ecosystem C stocks of coastal wetlands of the Sian Ka'an Biosphere Reserve (SKBR) in the Yucatan Peninsula, Mexico. We stratified the SKBR into different vegetation types (tall, medium and dwarf mangroves, and marshes), and examined relationships of environmental variables with C stocks. At nine sites within SKBR, we quantified ecosystem C stocks through measurement of above and belowground biomass, downed wood, and soil C. Additionally, we measured nitrogen (N) and phosphorus (P) from the soil and interstitial salinity. Tall mangroves had the highest C stocks (987 ± 338 Mg ha⁻¹) followed by medium mangroves (623 ± 41 Mg ha⁻¹), dwarf mangroves (381 ± 52 Mg ha⁻¹) and marshes (177 ±73 Mg ha⁻¹). At all sites, soil C comprised the majority of the ecosystem C stocks (78-99%). Highest C stocks were measured in soils that were relatively low in salinity, high in P and low in N: P, suggesting that P limits C sequestration and accumulation potential. In this karstic area, coastal wetlands, especially mangroves, are important C stocks. At the landscape scale, the coastal wetlands of Sian Ka'an covering approximate to ≈172,176 ha may store 43.2 to 58.0 million Mg of C.Keywords: Ignition, Sea level, Mangrove forests, Enrichment, Organic matter, Florida, Biomass, Sediments, Nutrient dynamics, Brazilian AmazonKeywords: Ignition, Sea level, Mangrove forests, Enrichment, Organic matter, Florida, Biomass, Sediments, Nutrient dynamics, Brazilian Amazo

The ocean sampling day consortium

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

First Latin American clinical practice guidelines for the treatment of systemic lupus erythematosus: Latin American Group for the Study of Lupus (GLADEL, Grupo Latino Americano de Estudio del Lupus)-Pan-American League of Associations of Rheumatology (PANLAR)

Systemic lupus erythematosus (SLE), a complex and heterogeneous autoimmune disease, represents a significant challenge for both diagnosis and treatment. Patients with SLE in Latin America face special problems that should be considered when therapeutic guidelines are developed. The objective of the study is to develop clinical practice guidelines for Latin American patients with lupus. Two independent teams (rheumatologists with experience in lupus management and methodologists) had an initial meeting in Panama City, Panama, in April 2016. They selected a list of questions for the clinical problems most commonly seen in Latin American patients with SLE. These were addressed with the best available evidence and summarised in a standardised format following the Grading of Recommendations Assessment, Development and Evaluation approach. All preliminary findings were discussed in a second face-to-face meeting in Washington, DC, in November 2016. As a result, nine organ/system sections are presented with the main findings; an 'overarching' treatment approach was added. Special emphasis was made on regional implementation issues. Best pharmacologic options were examined for musculoskeletal, mucocutaneous, kidney, cardiac, pulmonary, neuropsychiatric, haematological manifestations and the antiphospholipid syndrome. The roles of main therapeutic options (ie, glucocorticoids, antimalarials, immunosuppressant agents, therapeutic plasma exchange, belimumab, rituximab, abatacept, low-dose aspirin and anticoagulants) were summarised in each section. In all cases, benefits and harms, certainty of the evidence, values and preferences, feasibility, acceptability and equity issues were considered to produce a recommendation with special focus on ethnic and socioeconomic aspects. Guidelines for Latin American patients with lupus have been developed and could be used in similar settings.Fil: Pons Estel, Bernardo A.. Centro Regional de Enfermedades Autoinmunes y Reumáticas; ArgentinaFil: Bonfa, Eloisa. Universidade de Sao Paulo; BrasilFil: Soriano, Enrique R.. Instituto Universitario Hospital Italiano de Buenos Aires. Rectorado.; ArgentinaFil: Cardiel, Mario H.. Centro de Investigación Clínica de Morelia; MéxicoFil: Izcovich, Ariel. Hospital Alemán; ArgentinaFil: Popoff, Federico. Hospital Aleman; ArgentinaFil: Criniti, Juan M.. Hospital Alemán; ArgentinaFil: Vásquez, Gloria. Universidad de Antioquia; ColombiaFil: Massardo, Loreto. Universidad San Sebastián; ChileFil: Duarte, Margarita. Hospital de Clínicas; ParaguayFil: Barile Fabris, Leonor A.. Hospital Angeles del Pedregal; MéxicoFil: García, Mercedes A.. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Amigo, Mary Carmen. Centro Médico Abc; MéxicoFil: Espada, Graciela. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Catoggio, Luis J.. Hospital Italiano. Instituto Universitario. Escuela de Medicina; ArgentinaFil: Sato, Emilia Inoue. Universidade Federal de Sao Paulo; BrasilFil: Levy, Roger A.. Universidade do Estado de Rio do Janeiro; BrasilFil: Acevedo Vásquez, Eduardo M.. Universidad Nacional Mayor de San Marcos; PerúFil: Chacón Díaz, Rosa. Policlínica Méndez Gimón; VenezuelaFil: Galarza Maldonado, Claudio M.. Corporación Médica Monte Sinaí; EcuadorFil: Iglesias Gamarra, Antonio J.. Universidad Nacional de Colombia; ColombiaFil: Molina, José Fernando. Centro Integral de Reumatología; ColombiaFil: Neira, Oscar. Universidad de Chile; ChileFil: Silva, Clóvis A.. Universidade de Sao Paulo; BrasilFil: Vargas Peña, Andrea. Hospital Pasteur Montevideo; UruguayFil: Gómez Puerta, José A.. Hospital Clinic Barcelona; EspañaFil: Scolnik, Marina. Instituto Universitario Hospital Italiano de Buenos Aires. Rectorado.; ArgentinaFil: Pons Estel, Guillermo J.. Centro Regional de Enfermedades Autoinmunes y Reumáticas; Argentina. Hospital Provincial de Rosario; ArgentinaFil: Ugolini Lopes, Michelle R.. Universidade de Sao Paulo; BrasilFil: Savio, Verónica. Instituto Universitario Hospital Italiano de Buenos Aires. Rectorado.; ArgentinaFil: Drenkard, Cristina. University of Emory; Estados UnidosFil: Alvarellos, Alejandro J.. Hospital Privado Universitario de Córdoba; ArgentinaFil: Ugarte Gil, Manuel F.. Universidad Cientifica del Sur; Perú. Hospital Nacional Guillermo Almenara Irigoyen; PerúFil: Babini, Alejandra. Instituto Universitario Hospital Italiano de Buenos Aires. Rectorado.; ArgentinaFil: Cavalcanti, André. Universidade Federal de Pernambuco; BrasilFil: Cardoso Linhares, Fernanda Athayde. Hospital Pasteur Montevideo; UruguayFil: Haye Salinas, Maria Jezabel. Hospital Privado Universitario de Córdoba; ArgentinaFil: Fuentes Silva, Yurilis J.. Universidad de Oriente - Núcleo Bolívar; VenezuelaFil: Montandon De Oliveira E Silva, Ana Carolina. Universidade Federal de Goiás; BrasilFil: Eraso Garnica, Ruth M.. Universidad de Antioquia; ColombiaFil: Herrera Uribe, Sebastián. Hospital General de Medellin Luz Castro de Gutiérrez; ColombiaFil: Gómez Martín, DIana. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Robaina Sevrini, Ricardo. Universidad de la República; UruguayFil: Quintana, Rosana M.. Hospital Provincial de Rosario; Argentina. Centro Regional de Enfermedades Autoinmunes y Reumáticas; ArgentinaFil: Gordon, Sergio. Hospital Interzonal General de Agudos Dr Oscar Alende. Unidad de Reumatología y Enfermedades Autoinmunes Sistémicas; ArgentinaFil: Fragoso Loyo, Hilda. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Rosario, Violeta. Hospital Docente Padre Billini; República DominicanaFil: Saurit, Verónica. Hospital Privado Universitario de Córdoba; ArgentinaFil: Appenzeller, Simone. Universidade Estadual de Campinas; BrasilFil: Dos Reis Neto, Edgard Torres. Universidade Federal de Sao Paulo; BrasilFil: Cieza, Jorge. Hospital Nacional Edgardo Rebagliati Martins; PerúFil: González Naranjo, Luis A.. Universidad de Antioquia; ColombiaFil: González Bello, Yelitza C.. Ceibac; MéxicoFil: Collado, María Victoria. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Sarano, Judith. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Retamozo, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Sattler, María E.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Gamboa Cárdenas, Rocio V.. Hospital Nacional Guillermo Almenara Irigoyen; PerúFil: Cairoli, Ernesto. Universidad de la República; UruguayFil: Conti, Silvana M.. Hospital Provincial de Rosario; ArgentinaFil: Amezcua Guerra, Luis M.. Instituto Nacional de Cardiologia Ignacio Chavez; MéxicoFil: Silveira, Luis H.. Instituto Nacional de Cardiologia Ignacio Chavez; MéxicoFil: Borba, Eduardo F.. Universidade de Sao Paulo; BrasilFil: Pera, Mariana A.. Hospital Interzonal General de Agudos General San Martín; ArgentinaFil: Alba Moreyra, Paula B.. Universidad Nacional de Córdoba. Facultad de Medicina; ArgentinaFil: Arturi, Valeria. Hospital Interzonal General de Agudos General San Martín; ArgentinaFil: Berbotto, Guillermo A.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Gerling, Cristian. Hospital Interzonal General de Agudos Dr Oscar Alende. Unidad de Reumatología y Enfermedades Autoinmunes Sistémicas; ArgentinaFil: Gobbi, Carla Andrea. Universidad Nacional de Córdoba. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gervasoni, Viviana L.. Hospital Provincial de Rosario; ArgentinaFil: Scherbarth, Hugo R.. Hospital Interzonal General de Agudos Dr Oscar Alende. Unidad de Reumatología y Enfermedades Autoinmunes Sistémicas; ArgentinaFil: Brenol, João C. Tavares. Hospital de Clinicas de Porto Alegre; BrasilFil: Cavalcanti, Fernando. Universidade Federal de Pernambuco; BrasilFil: Costallat, Lilian T. Lavras. Universidade Estadual de Campinas; BrasilFil: Da Silva, Nilzio A.. Universidade Federal de Goiás; BrasilFil: Monticielo, Odirlei A.. Hospital de Clinicas de Porto Alegre; BrasilFil: Seguro, Luciana Parente Costa. Universidade de Sao Paulo; BrasilFil: Xavier, Ricardo M.. Hospital de Clinicas de Porto Alegre; BrasilFil: Llanos, Carolina. Universidad Católica de Chile; ChileFil: Montúfar Guardado, Rubén A.. Instituto Salvadoreño de la Seguridad Social; El SalvadorFil: Garcia De La Torre, Ignacio. Hospital General de Occidente; MéxicoFil: Pineda, Carlos. Instituto Nacional de Rehabilitación; MéxicoFil: Portela Hernández, Margarita. Umae Hospital de Especialidades Centro Medico Nacional Siglo Xxi; MéxicoFil: Danza, Alvaro. Hospital Pasteur Montevideo; UruguayFil: Guibert Toledano, Marlene. Medical-surgical Research Center; CubaFil: Reyes, Gil Llerena. Medical-surgical Research Center; CubaFil: Acosta Colman, Maria Isabel. Hospital de Clínicas; ParaguayFil: Aquino, Alicia M.. Hospital de Clínicas; ParaguayFil: Mora Trujillo, Claudia S.. Hospital Nacional Edgardo Rebagliati Martins; PerúFil: Muñoz Louis, Roberto. Hospital Docente Padre Billini; República DominicanaFil: García Valladares, Ignacio. Centro de Estudios de Investigación Básica y Clínica; MéxicoFil: Orozco, María Celeste. Instituto de Rehabilitación Psicofísica; ArgentinaFil: Burgos, Paula I.. Pontificia Universidad Católica de Chile; ChileFil: Betancur, Graciela V.. Instituto de Rehabilitación Psicofísica; ArgentinaFil: Alarcón, Graciela S.. Universidad Peruana Cayetano Heredia; Perú. University of Alabama at Birmingahm; Estados Unido

The Ocean Sampling Day Consortium

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