Mexico : Cancun Braces For Worst Sargassum Seaweed Season In Five Years

New reports are suggesting that Quintana Roo’s sargassum season could be the worst in five years, worrying the tourist industry. Tens of thousands of tons of seaweed have already been deposited on beaches across the Caribbean. Sargassum is a brown type of seaweed that is known for accumulating on Cancun beaches during the spring and summer months.

The National Autonomous University Of Mexico has been following the sargassum since it first began appearing in large quantities back in 2014. The levels steadily increased, peaking in around 2018/2019 before showing signs of a slight dip in 2020. There is some speculation that this may have been attributed to the pandemic and the drop in carbon usage across the planet that came with it.

However, 2022 is seeing deposit rates and volumes that are higher than those in 2018. At least 32 thousand tons have been forecasted to arrive on Quintana Roo’s beaches over the coming weeks- an extremely high volume.

Sadly, the state is unable to keep up with the deposits despite its best efforts. Multiple methods are used in the fight against sargassum. Early detection is captured using drones, hot air balloons, and planes as well as satellite imagery from universities that study the natural phenomenon. It was hoped that the early detection would allow the navy to retrieve large amounts of the seaweed before it hit the shore, but multiple problems have surfaced preventing that from happening.

The Navy released 26 ships from Chetumal two weeks ago with the sole purpose of dealing with the sargassum, but poor weather is hampering the efforts. At least two of those ships are sargacerro ships, large vessels designed to collect masses of seaweed far out at sea. In theory, the high volumes these ships could pick up can make life much easier, but each year the ships are having a decreasing impact on the effort.

According to the statistics, 2020 saw the Navy pull only 4% of the seaweed collected from the ocean. 3% of the collected sargassum in 2021 was collected from the sea. 2022’s collection rate is down at 1%, meaning that 99% of all the seaweed reaching the Mexican Caribbean is being collected manually by workers on the beach.

The amount of workers needed to clear the beaches is severely hampering businesses’ bottom lines. Most hotels reported considerable drops in profit despite having extremely strong years in terms of occupancy. The amount being spent to hire people to clean the beaches in the morning is eating into profit margins, and when combined with remaining COVID restrictions like masks, enhanced cleaning, and other precautions it could spell rate increases for tourists.

For those unaware of sargassum, it may seem like a small problem. In reality, it’s one of the biggest issues facing the Caribbean. The seaweed forms into massive island-like tangles far out in the Atlantic Ocean, and drifts on ocean currents towards the Caribbean. At sea, it poses virtually no problems for the tourism industry and is actually an important ecosystem for many small sea creatures.

When it approaches land, it becomes more complicated. When it reaches the shallows, it transforms the typically crystal blue waters of the Mexican Caribbean into a murky brown, ruining the aesthetic that so many travel to the region for. On the sand, it piles up as high as a meter, having a similar impact as the brown water.

The biggest problem is the smell. Once on land, the sargassum begins to break down and produces a putrid sulfur-like smell in the process. Any tourists nearby avoid it, and beaches are often empty when the deposits are heavier.

Many tourists go as far as canceling their vacations if they’re aware of large deposits as the beach is such an integral part of the experience.

Source / Fuente : https://thecancunsun.com/  6th May 2022

Guadeloupe : Guadeloupe : Les sargasses s’accumulent, les nuisances olfactives et visuelles reviennent

POLLUTION Du matériel majoritairement financé par l’Etat est attendu pour retirer les algues

D’importantes masses de sargasses sont présentes le long de la côte nord-est de Grande-Terre (Guadeloupe). Photo d’illustration. — GILLES MOREL/SIPA

Des plages du nord-est de Grande Terre (Guadeloupe) ont une fois de plus été touchées par un échouement massif de sargasses. C’est la onzième fois depuis 2011 que le phénomène est observé. L’arrivée des algues marron a notamment touché la plage de la Porte d’Enfer, à Anse-Bertrand (Guadeloupe), particulièrement fréquentée à cette période de l’année, raconte La Première.

Une odeur désagréable
Le site est en effet plébiscité par les touristes comme les Guadeloupéens puisqu’il offre un accès à la mer ainsi que de nombreux chemins de randonnée. La présence de sargasses stagnantes constitue une nuisance olfactive et visuelle contre laquelle il est difficile de lutter. L’immense quantité d’algues déposées ne peut être dégagée efficacement qu’avec des machines.

La municipalité d’Anse-Bertrand a lancé un appel d’offres pour choisir l’entreprise qui ramassera les sargasses. L’opération commencera quand le matériel financé à 80 % par la préfecture sera livré. La commune dispose déjà d’un camion et attend désormais une tractopelle, un tracteur et une cribleuse.

Source: 20minutes.fr du 27/04/2022

Mexico – Riviera Maya : ADVIERTEN OPACIDAD EN EL TEMA DE DISPOSICIÓN Y MANEJO DEL SARGAZO

Cancún (Carlos Águila Arreola / 5to Poder).- En el polémico y “ardiente” tema del sargazo, su recolección y disposición final, tema que se repite año con año desde ya siete desde que empezó el recale masivo, “dinero hay, lo que falta, a veces, son ganas, interés también de hacerlo bien”, denunció la científica Rosa Elisa Rodríguez Martínez

Durante el conversatorio “Arribazones de sargazo en el Caribe mexicano”, las consideradas mejores exponentes del tema —la propia Rosa Elisa y Brigitta Ine van Tussenbroek, ambas del Instituto de Ciencias del Mar y Limnología, Unidad Sistemas Arrecifales, en Puerto Morelos—, también hablaron de opacidad.

A pregunta expresa sobre por qué en seis años —concediendo que 2015 fue el primer recale masivo y no se supo qué hacer— sólo hay un sitio de disposición en el estado, el de Solidaridad, la subsecretaria de Política Ambiental de la SEMA, Graciela Saldaña Fraire, quiso “componer el cuadro”.

La funcionaria señaló, palabras más, palabras menos, que ya se habilitó un predio en Tulum —no dijo dónde se ubica; ya antes grupos ambientalistas se opusieron a la habilitación de uno por la zona de Xcacel-Xcacelito— al que “solo falta colocarle la geomembrana para ya entregarlo”.

En ese sentido, ni la SEMA ni el gobierno del estado han expuesto las razones por las que siete años después del primer desastroso arribo masivo de sargazo solo uno de 10 municipios tiene un sitio de disposición; si bien se entiende que es una irresponsabilidad compartida con la administración anterior.

Rosa Elisa Rodríguez intervino: “El derecho de saneamiento ambiental (…) se les cobra a los turistas diciendo que es para limpiar de sargazo las playas. Me metí a pedir por Transparencia cuánto dinero es, y nada más de Solidaridad y Benito Juárez son como 400 millones de pesos al año”.

“Creo que con ese dinero es suficiente… hasta con 25 por ciento (100 millones) para los centros de disposición y dar más dinero a municipios y a la (Secretaría de) Marina para que hagan un mejor trabajo y que todos los municipios deben de tener un fidecomiso para ver cómo se administra ese dinero.

“Y debe haber mucha transparencia —entonces, hay mucha opacidad— porque además de eso está lo de zofemat (zona federal marítimo terrestre), que es otro dineral. Entonces, dinero hay, lo que falta, a veces, son ganas, interés también de hacerlo bien, pero… bueno, ahí lo dejo sobre la mesa”, dijo la investigadora.

Fuente / Source : quintopoderqrp.com 24/04/2022

Mexico – Riviera Maya : El sargazo se adelanta y pega con más intensidad

Investigadores del ICAyCC estudian el fenómeno, sus orígenes, desplazamientos y arribazones, para proponer medidas de contención

Foto: Rosa Elisa Rodríguez

Al igual que cada año, aunque esta vez antes de lo que se preveía, el sargazo –un género de macroalga de color marrón que forma colonias que cubren enormes extensiones del Atlántico tropical– ha comenzado a arribar a las costas del Caribe mexicano y a causar grandes problemas a los ecosistemas y la industria turística de la zona.
Con el propósito de comprender mejor este fenómeno y proponer algunas medidas que permitan hacerle frente con más eficacia, investigadores del Instituto de Ciencias de la Atmósfera y Cambio Climático (ICAyCC) estudian la variabilidad interanual de sus arribazones y sus patrones de desplazamiento.

“A finales de 2021, Daniel Robles, alumno del Posgrado en Ciencias de la Tierra, terminó una tesis de maestría en la que señaló que hay años en que el sargazo es más abundante que en otros, y que esto se relaciona con la variabilidad climática de las condiciones atmosféricas y oceánicas en el Atlántico tropical”, dice Jorge Zavala Hidalgo, director del mencionado instituto.

El resultado más interesante de este trabajo es que los años en que el sargazo se presenta con más abundancia, los vientos alisios son un poco más intensos, las temperaturas superficiales del mar son un poco más bajas y la profundidad de la capa de mezcla oceánica resulta un poco mayor.

“Ahí se encuentra una relación que puede ayudar a explicar la variabilidad interanual del sargazo. Una posible hipótesis es que la intrusión de aguas subsuperficiales más ricas en nutrientes en la zona donde penetra la luz solar, llamada zona fótica, contribuye a que el sargazo sea más abundante ciertos años”, comenta Zavala Hidalgo.

En sus investigaciones, Robles encontró que hacia 2010 se dio un cambio en los patrones de la capa superficial del Atlántico tropical y desde entonces ha habido años con más sargazo y años con menos sargazo en el Caribe, en general, y en el Caribe mexicano, en particular.

“Aquí surge una pregunta: ¿cómo estamos en 2022? En cuanto a la temperatura superficial del Atlántico tropical, está muy cerca de la media, ligeramente por arriba. Es decir, éste no es uno de los años más fríos; pero sí se ha observado que está llegando bastante sargazo”, indica Zavala Hidalgo.

Ciclo estacional
El sargazo se genera en algunas regiones del Atlántico nortropical y crece rápidamente (se sabe que, a pesar de que una parte de él muere, en pocos días se multiplica de manera exponencial).

Durante los meses del invierno (enero, febrero y marzo) prácticamente no hay sargazo en las costas del Caribe mexicano. Es a partir de que entra la primavera cuando empieza a multiplicarse y a arribar poco a poco a ellas. En el verano, sus arribazones alcanzan su pico más alto y cuando entra el otoño decaen de nuevo.

“Gracias a imágenes tomadas por satélites, dos meses antes del inicio de la temporada se puede ver si hay mucho o no hay mucho sargazo en el Caribe oriental. No parece que este año vaya a llegar tanto a las costas del Caribe mexicano como en 2018, lo cual coincide con el hecho de que la temperatura superficial del Atlántico tropical no está por debajo del promedio. Sin embargo, a diferencia de 2020 y 2021, este año llegó a dichas costas desde enero y ahora, en abril, se ve un poco más que en abril de esos años”, afirma Zavala Hidalgo.

Foto: Reuters.

Modelos numéricos
Para la contención del sargazo se ha recurrido a tres estrategias: poner barreras cerca de las zonas a donde puede arribar, sacarlo del agua con unas embarcaciones especializadas conocidas como sargaceras y recolectarlo directamente de las playas.

“A veces, puede llegar a un lugar como Tulum, pero no a un sitio vecino como Akumal, o viceversa, o a los dos, o unos días a uno y otros días a otro. Por eso, desde 2015 hemos propuesto llevar a cabo estudios para estar en condiciones de pronosticar a qué lugares, cuándo y en qué cantidad podrá arribar. Éste es uno de nuestros mayores retos.”

Julio Lara, otro alumno del Posgrado en Ciencias de la Tierra, ha hecho modelos numéricos para identificar las zonas que abastecen de sargazo a algunas costas mexicanas y tratar de entender dónde estaba 24 y 48 horas antes el que llegó a un sitio específico en una fecha determinada.

“Cuando estos modelos numéricos queden validados no será necesario monitorear todas las regiones, sino sólo algunas, para saber, dentro de esa variabilidad temporal, cuándo habría mayores o menores arribazones de sargazo en un lugar específico. El objetivo es ayudar en las estrategias de contención y recolección, y minimizar su impacto en las costas”, apunta Zavala Hidalgo.

En conjunto con otros grupos de la Escuela Nacional de Estudios Superiores, Unidad Mérida, de la UNAM, donde se imparte la licenciatura en Ciencias de la Tierra, integrantes del Instituto de Ciencias de la Atmósfera y Cambio Climático también han monitoreado, mediante pequeñas boyas puestas sobre las manchas o camas de sargazo, el desplazamiento de éstas hasta su arribo a las costas del Caribe mexicano.

“Esto nos resulta muy útil para saber qué trayectoria siguen, pero también para calibrar, evaluar y validar los modelos numéricos antes mencionados.”

Emanaciones y toxicidad
Por otro lado, Telma Castro Romero, especialista en Química de la atmósfera del ICAyCC, participa en un proyecto para medir las emanaciones del sargazo que llega a la playa, así como su toxicidad.

“Como se sabe, cuando grandes concentraciones de sargazo se descomponen, el olor que se desprende de ellas es muy agresivo y desagradable; además, irrita las vías respiratorias y puede tener consecuencias en la salud de las personas”, finaliza Zavala Hidalgo.

COLABORACIÓN
El Laboratorio Nacional de Observación de la Tierra del Instituto de Geografía trabaja con algoritmos y combina información de distintos satélites de diversas tecnologías para identificar manchas de sargazo en el Caribe.

“Nosotros necesitamos que nos digan dónde hay una mancha de sargazo y con esa información podemos hacer un modelo numérico que nos indique cómo se moverá las próximas horas y los próximos días”, expresa Jorge Zavala.

Igualmente, con el Centro de Investigación Científica y de Educación Superior de Ensenada, en Baja California, el Instituto de Ciencias de la Atmósfera y Cambio Climático colabora en la elaboración de los modelos numéricos oceánicos y atmosféricos, entre otras cosas.

Fuente/Source: gaceta.unam.mx 25/04/2022

Mexico : Sin recursos ni personal suficiente para contener el sargazo; aún desatendidas, enormes extensiones en las costas del Caribe mexicano

En enero hubo algunas arribazones, cuando normalmente comienzan a presentarse en marzo; se espera una temporada complicada este año

Abril 26, 2022

Por UNAM

Este año, el sargazo llegó más temprano que de costumbre a las costas del Caribe mexicano. Ya en enero hubo algunas arribazones, cuando normalmente empiezan a presentarse en marzo; y a partir de marzo ha habido otras que se parecen a las de 2018, año en que se registró el récord de más sargazo en la zona.

“Todavía no se sabe si la llegada del sargazo a las costas del Caribe mexicano se incrementó este año con respecto a años anteriores, porque los meses en que arriba en mayor cantidad son mayo y junio. Sin embargo, de acuerdo con imágenes satelitales, 2022 podría ser un año difícil, no sé si más que 2018, pero sí similar”, dice Rosa Elisa Rodríguez Martínez, especialista de la Unidad Académica de Sistemas Arrecifales del Instituto de Ciencias del Mar y Limnología, ubicada en Puerto Morelos, Quintana Roo.

Los grandes hoteles han colocado barreras en el mar para impedir el paso del sargazo y lo recolectan ahí mismo; otros disponen de bandas para transportarlo desde las playas hasta una planta especial en la que se recupera la arena que atrapa. En cambio, los hoteles pequeños lo recogen de manera manual, con trinches y carretillas.

En cuanto a las playas públicas, los municipios también han puesto barreras en el mar y, con el apoyo de la Marina, recolectan el sargazo que se acumula en ellas.

“Sí se ha avanzado para tratar de mantener bajo control el sargazo. La Secretaría de Medio Ambiente y Recursos Naturales (Semarnat) ha emitido los lineamientos de lo que se debe y no se debe hacer en relación con este tema. No obstante, hay enormes extensiones en las costas del Caribe mexicano que aún no son atendidas por falta de presupuesto y personal”, señala la académica universitaria.

Primera medida y problemas de salud

La primera medida que hay que poner en práctica es impedir que el sargazo llegue a las playas. Si se coloca una barrera en el mar y se recoge ahí, su impacto no resulta tan grave; pero cuando llega a una playa y se mezcla con la arena, ocasiona erosión en el lugar una vez que se le retira.

“Ahora bien, cuando la cantidad de sargazo es muy grande y no se recolecta a tiempo (de uno a dos días después de su arribo a una playa), empieza a descomponerse y a generar gases tóxicos, como gas de ácido sulfhídrico y metano, y lixiviados que contienen metales, entre los cuales destaca por su peligrosidad el arsénico (se ha encontrado en concentraciones altas en muchos lugares del Caribe donde recala). Por eso, hay que recogerlo lo más pronto posible, antes de que regrese al mar, y llevarlo a sitios habilitados para su disposición final”, indica Rodríguez Martínez.

En ocasiones, el sargazo trae organismos pegados que causan dermatitis y los gases que generan cuando se descomponen pueden dar origen a problemas respiratorios y dolores de cabeza y, en la gente que vive cerca de las playas y está expuesta a él durante meses, problemas pulmonares y neurológicos.

Unas veces, esta macroalga es retirada de una playa y llevada a una “de sacrifico”, y entonces, al cabo de unos días, los lixiviados se van al mar; otras se tiran en calles, camellones o terrenos baldíos, incluso en la selva o el manglar.

Eso se ha venido dando desde 2015 porque se carece de sitios adecuados de disposición final de sargazo. Hace dos o tres años, la Secretaría de Ecología y Medio Ambiente (Sema) de Quintana Roo otorgó a cada municipio un terreno para ese propósito, pero la mayoría de ellos no sirven porque se localizan en zonas de selva (algunos cerca de cenotes), no están habilitados, no disponen de una geomembrana y no cuentan con personal ni con maquinaria.

“El municipio Solidaridad es el único que lleva su sargazo a un centro de manejo de residuos sólidos. Los demás recurren a sascaberas (canteras o pozos de sascab, una especie de tierra blanca caliza), por lo que los lixiviados se van al acuífero; asimismo, el sargazo puede estar secando la vegetación de los alrededores porque, además, contiene muchas sales”, explica la científica.

Ventana de oportunidad

Sin duda, el sargazo representa un peligro tanto para los ecosistemas como para la industria turística de la zona, pero también una ventana de oportunidad.

En Quintana Roo, una empresa ya produce bioestimulantes (sustancias o microorganismos que modulan procesos fisiológicos y bioquímicos de las plantas) a partir del sargazo. Y otra que todavía no opera porque no ha obtenido los permisos necesarios producirá fertilizantes también a partir del sargazo. De igual modo, en Puerto Morelos, una pequeña empresa ya elabora, con una mezcla de sargazo y arcilla, bloques para construir viviendas. Y en Playa del Carmen, otra compañía mezcla sargazo con concreto para fabricar lo que se conoce como sargacreto.

“Por si fuera poco, el sargazo contiene aminoácidos, proteínas y compuestos antivirales, antimicrobianos y para regular la presión arterial que podrían utilizarse en las industrias alimenticia (en animales de crianza para consumo humano) y farmacéutica”, apunta Rodríguez Martínez.

El dinero desviado

Los turistas que viajan a Quintana Roo tienen que pagar una cuota de poco más de 20 pesos por noche para cubrir el denominado Derecho de Saneamiento Ambiental. Originalmente, el dinero recaudado por este derecho se destinaba a hacerle frente al sargazo, pero después se empezó a usar para otras cosas.

Así pues, hoy en día, el presupuesto del gobierno federal y de los municipios para atender las arribazones de sargazo y mitigar su impacto en las costas del Caribe mexicano es muy bajo.

En relación con ese punto, la académica comenta: “Habría que asignar más dinero para combatir el sargazo y hacer funcionales los sitios de su disposición final. Esto evitaría que nuestros recursos costeros (selva, manglar, playas, laguna arrecifal, arrecife y acuífero) siguieran contaminándose. También es importante acelerar los trámites de permisos para que las empresas puedan invertir en personal y maquinaria, y aprovecharlo como materia prima.”

Fuente/Source: nadietepregunto.com.mx 26/04/2022

MEXICO : PRIORITARIO RECURSOS Y PROTECCIÓN INTEGRAL PARA ATENCIÓN DEL SARGAZO

Rosa Elisa Rodríguez Martínez - UNAM Puerto Morelos
Rosa Elisa Rodríguez Martínez – UNAM Puerto Morelos
  • Destacaron las científicas Rosa Elisa Rodríguez Martínez y Brigitta Ine van Tussenbroek en la conferencia «Arribazones de sargazo en el Caribe Mexicano”
  • Ofrecida por el gobierno de Quintana Roo en el marco del día Mundial de la Tierra

Chetumal.- En el marco del Día Mundial de la Tierra el gobierno de Quintana Roo presidido por Carlos Joaquín a través de la Secretaría de Ecología y Medio Ambiente (SEMA), en coordinación con el Instituto de Ciencias del Mar y Limnología UNAM de Puerto Morelos, ofreció la conferencia magistral «Arribazones de sargazo en el Caribe Mexicano”, impartida las científicas Rosa Elisa Rodríguez Martínez y Brigitta Ine van Tussenbroek.

Rosa Elisa Rodríguez Martínez, durante la conferencia de las Jornadas de Educación Ambiental “Reconecta con la Naturaleza” resaltó que, es prioritario destinar más recursos y protección integral para la atención del sargazo y evitar implicaciones económicas y ecológicas. “Hasta ahora -dijo Rodríguez- hay avances en México, pero son insuficientes por la magnitud del problema que ocasiona el alga marina”.

Rodríguez Martínez puntualizó que, hay probabilidades que a futuro lleguen otro tipo de algas a las costas (ha sucedido en otras partes del mundo) y se puede empezar a perder los ecosistemas y afectar a las pesquerías. La científica recomendó que desde casa iniciemos acciones para reducir el cambio climático y la contaminación al planeta, de lo contrario este tipo de problemática continuará.

Brigitta Ine van Tussenbroek acotó que el sargazo es un problema complejo, no hay solución sencilla, se requieren muchos recursos, mucha voluntad política. Vivimos -dijo- en un lugar increíble, con un recurso invaluable: el mar, el sol y el azul turquesa del caribe que era gratuito, no nos costaba, ahora sí, es necesario destinar los recursos para preservar los ecosistemas, de lo contrario se van a perder. Una vez que colapsen – sentenció Ine van Tussenbroek- ya no hay cuenta de reinicio. Brigitta hizo un llamado al igual que su antecesora a sumar esfuerzos para que cada uno colabore al cuidado del planeta.

La Subsecretaría de Política Ambiental de la SEMA, al invitar a todas y todos los participantes a fomentar el equilibrio entre las necesidades económicas, sociales y ambientales y futuras, reafirmando el desarrollo sostenible; recordó el trabajo permanente que realiza la SEMA junto con Ayuntamientos y la Secretaría de Marina (SEMAR) para combatir el fenómeno.

Fuente/Source : QUEQUI 22 de Abril 2022

Mexico – Acuario de mantarrayas en Cozumel es invadido por el sargazo

Acuario de mantarrayas en Cozumel es invadido por el sargazo [Foto: Gustavo Villegas]
El acuario de mantarrayas y tiburones gata, ubicado en Cozumel sufrió las consecuencias del arribo masivo del sargazo, pues este atractivo quedó como una alberca invadida de estás algas marinas.

De acuerdo con la información, los empleados de la empresa Stingray ya comenzaron a retirar el sargazo del área, sin embargo se desconocen las condiciones de los animales marinos que son explotados en ese acuario como atractivo para el turismo de cruceros.

Según los datos proporcionados por el titular de Zofemat, José Rafael López Saavedra, este asunto debe ser atendido por las autoridades ambientales federales ya que el polígono afectado se localiza en la Zona Federal. Anque se revela que hasta el momento no se han contactado con la dependencia ya mencionada.

Cozumel invadido por el sargazo
Desde el viernes la zona Oeste de Cozumel comenzó a recibir « manchones » de las algas marinas, que en esa zona son arrastradas por las corrientes y son muy pocos los sitios en los que se acumulan, mismos que son retirados por el personal de la dirección de Zona Federal Marítimo Terrestre (Zofemat), de inmediato.

Germán Yáñez Mendoza, Subdirector de Ecología, fue consultado sobre la competencia de esa área del ayuntamiento para sancionar alguna negligencia, descuido o afectación a los organismos marinos que ahí están en cautiverio. Mendoza indicó que esto es competencia de Zofemat.

Sin embargo, la ambientalista Guadalupe Álvarez Chulin, presidente de Cielo, Tierra y Mar ( Citymar), la Subdirección de Ecología debió levantar evidencia de asunto y enviar una denuncia a las autoridades ambientales federales, pues si bien no tiene facultades para sancionar, si puede alertar a la Profepa.

Fuente: Novedades Quintana RooCozumel 12 de abril 2022

Element concentrations in pelagic Sargassum along the Mexican Caribbean coast in 2018-2019

Rosa E. Rodríguez-Martínez ​​1, Priyadarsi D. Roy ​2, Nuria Torrescano-Valle 3, Nancy Cabanillas-Terán 3, 4, Silvia Carrillo-Domínguez 5, Ligia Collado-Vides 6, Marta García-Sánchez 1, 7, Brigitta I. van Tussenbroek 1

The west coast of Africa and some eastern Caribbean islands received unusual large quantities of pelagic Sargassum spp. (S. fluitans (Boergesen) Boergesen and S. natans (Linnaeus) Gallion; hereafter named sargasso) for the first time in 2011 (Gower, Young & King, 2013). In subsequent years, the range of massive sargasso influx extended over the Atlantic Ocean and whole Caribbean Sea. Wang et al. (2019) reported more than 20 million metric tons of sargasso in the open ocean in the peak month of June 2018, when the Great Atlantic Sargasso Belt extended for 8,850 km in total length. Beaching of sargasso has caused havoc to the Caribbean coastal ecosystems. Leachates and particulate organic matter from stranded decaying algal masses depleted the oxygen in near shore waters and reduced visibility of the water column, causing mortality of near-shore seagrasses and fauna (van Tussenbroek et al., 2017; Rodríguez-Martínez et al., 2019). Onshore and near shore masses of sargasso interfered with the seaward journeys of the juvenile turtles (Maurer, De Neef & Stapleton, 2015), affected sea turtle nestings (Maurer, Stapleton & Layman, 2018) and altered the trophic structure of the sea urchin Diadema antillarum in coastal marine systems (Cabanillas-Terán et al., 2019). Massive beachings also enhanced beach erosion (van Tussenbroek et al., 2017). Coastal ecosystem-based tourist industry is one of the major sources of income for the Caribbean countries (Langin, 2018) and the potential socio-economic impacts of ecosystem degradation due to sargasso influx have yet to be assessed.

The Mexican Caribbean coast began receiving massive amounts of sargasso during the late 2014 and it reached a peak in September 2015, when in the northern section of the coast between Cancun and Puerto Morelos an average of ∼2,360 m3 of algae (mixed with sand, seagrasses and other algae) arrived per km of coastline (Rodríguez-Martínez, van Tussenbroek & Jordán-Dahlgren, 2016). During 2016, and 2017, the influxes decreased, increasing again in 2018, when in the peak month May ∼8,793 m3 km−1 of algae (mixed with sand, seagrasses and other algae) were removed from the same shore section (Rodríguez-Martínez et al., 2019). In the tourist beaches, the algae removed from the beach and sea have been disposed in areas that are not properly prepared to avoid leakage of the leachates into the aquifer. In addition, the cleaning efforts have not covered the whole coastline and thousands of tons of sargasso have accumulated annually along the Mexican Caribbean coast.

Like other brown algae, species of Sargassum (including the pelagic ones) have high capacity to absorb metals and other elements (Kuyucak & Volesky, 1988; Davis, Volesky & Vieira, 2000). This high absorption capacity is attributed to the unique mixture of polysaccharides, mainly alginates, in their cell walls (Fourest & Volesky, 1997). At present, the Sargassum spp. are used for different commercial end products, such as fertilizers (Milledge & Harvey, 2016), textiles, paper and drugs (Oyesiku & Egunyomi, 2014), as well as in the production of biogas (Wang et al., 2018). They have also been increasingly used as food for animals and humans, and therefore the high concentrations of contaminants, including heavy metals, may pose potential health risks (Reis & Duarte, 2018). Therefore, it is mandatory to evaluate elemental concentrations to ensure that acceptable levels are maintained in terms of health regulations (e.g., Fourest & Volesky, 1997). Previous studies on metal contents in sargasso, were either based on limited number of samples collected mostly from a single locality (e.g., Nigeria Oyesiku & Egunyomi, 2014; Dominican Republic, Fernández et al., 2017) or in a single season (e.g., Addico & De Graft-Johnson, 2016). Hence, it is unclear how much the metal contents can vary in the algal tissues across sites and seasons and between species.

In this study, we estimate concentrations of 28 different elements in sargasso tissues collected from the Mexican Caribbean coast, covering a linear north-south distance of 370 km. We hypothesize that the elemental contents are variable both in time and space. The determinations of metals and other elements from this study provide an essential baseline data for adequate management and potential uses of sargasso.

Survey Methodology

Study sites

We collected 63 samples of sargasso along the Mexican Caribbean coast, from Contoy Island, at the northern extreme, to Xcalak in the south (Fig. 1). This region receives an average precipitation of ∼1,061 mm y−1 and the sea-surface temperature (SST) ranges from 25.1–29.9 °C (Rodríguez-Martínez et al., 2010). The Yucatan Current, a major branch of the Caribbean Current, transports the pelagic algal masses parallel to the Mexican Caribbean coastline. Easterly trade-winds dominate this region during the summer and mild cold fronts occur during the winter season. Trade-winds transport the superficial waters towards the shore, importing the pelagic masses of sargasso towards the coast.

Figure 1: Sampling sites. Location of the sampling sites of sargasso along the Mexican Caribbean coast between August 2018 and June 2019. Map produced in QGIS 2.18 (http://www.qgis.org) using the following data sources: National Geospatial-Intelligence Agency (base map, World Vector Shoreline Plus, 2004. http://shoreline.noaa.gov/data/datasheets/wvs.html). The location of survey sites was obtained from the present study. Data sources are open access under the Creative Commons License (CC BY 4.0).

The coastal environment consists of beaches, rocky shores, seagrass beds, coral reefs, mangroves, jungle and underground rivers (Hernández-Arana et al., 2015). All these ecosystems provide services to the tourism industry, a crucial component of the regional economy (Spalding et al., 2017). In the karstic Yucatan peninsula, the freshwater aquifer and seawater are constantly interacting; especially near the coast (Hernández-Terrones et al., 2011; Hernández-Terrones et al., 2015). This region has no other major industries besides tourism. At present, this region has the highest number of hotel rooms in Mexico and the number of rooms has increased from 3,206 in 1975 to 100,986 in 2017 (SEDETUR, 2019). Similarly, the resident population grew almost 15-folds, from less than 100,000 in 1970 to 1,501,785 in 2015 (INEGI, 2015). This rapid urban development has caused coastal pollution through influx of nutrients (Carruthers, van Tussenbroek & Dennison, 2005; Hernández-Terrones et al., 2011; Baker, Rodríguez-Martínez & Fogel, 2013; van Tussenbroek et al., 2017), sewage (Metcalfe et al., 2011), and some metals (e.g., Lead, see Whelan III, van Tussenbroek & Santos, 2011) into the coastal ecosystems.

Methodology

Field collection

Samples were collected between August 2018 and June 2019 from eight different sites along the Mexican Caribbean coast (from north to south): (1) Contoy Island, (2) Blue waters, (3) Puerto Morelos, (4) Cozumel, (5) Mahahual, (6) Chinchorro, (7) Xahuayxol and 8) Xcalak (Fig. 1, Table 1). Fresh sargasso (golden color) thalli floating near the shore (2–20 m) and in the ocean (>5 km from shore) were collected manually and separated in species and morphotypes (S. fluitans III, S. natans I and S. natans VIII) in the laboratory following Schell, Goodwin & Siuda (2015), except for the samples of Contoy Island (CI). The samples collected from CI were frozen before separating the specimens by species and morphotypes, thus, we classified them as Sargassum spp. All the samples were placed in an oven for at least 48 h at 60 °C until completely dry. Special caution was taken to avoid contact between the algal samples and any metal object. Samples were shipped to the Institute of Geology of the National Autonomous University of Mexico for the analysis of element concentrations. We did not remove epibionts from the thalli and analyzed the chemical composition of the algae including attached organisms, as the main interest of this study was to determine the potential contamination hazards and uses of sargasso as collected from the sea, without any specific separation treatment. All surveys were conducted under permit PPD/DGOPA-116/14 granted by SAGARPA (Agriculture, Natural Resources and Fisheries Secretariat) to B.I. van Tussenbroek.

Table 1:
Samples information.
Number of samples collected at eight sites along the Mexican Caribbean coast during 2018–2019. Habitat refers to distance from coast, shore (2–20 m from coast) or ocean (>5 km from coast).

Notes: Sarg sp: Sargassum spp., Sflu III: Sargassum fluitans III, Snat I: S. natans I, Snat VIII: S. natans VIII.

Elemental analysis

Concentrations of 28 different elements were measured in dry samples using a Niton FXL 950 energy dispersive X-ray fluorescence (XRF) containing a 50 kV X-ray tube of Ag and equipped with a geometrically optimized large area drift defector following Quiroz-Jiménez & Roy (2017). Table S1 shows the limit of detection of these elements. The dried samples were processed in the laboratory using a non-destructive sample preparation technique. Approximately 5–7 dry g of each sample was placed in a plastic capsule that has a 4µm thick polypropylene X-ray film on one side and the other side of the capsule was packed with synthetic flexible gauze. The samples were measured in the mining Cu/Zn mode and three different filters using the internal calibration curves previously generated by comparing the results of Niton FXL with a conventional XRF (e.g., Quiroz-Jiménez & Roy, 2017). The results are expressed in parts per million dry weight (ppm DW) after carrying out the analysis in five repetitions in each sample. We used two different geological reference materials (Es-2, organic rich argillite and Es-4, dolostone) for estimation of precision (Kiipli et al., 2000). Except for Mg, all other elements have relative standard deviation (RSD) between <1 and 5%. Mg concentrations show RSD of 26% and it is the least precise among all the analyzed elements. Some advantages of the XRF analysis compared to other methodologies are that small samples are required (∼5 g), the results have high precision, and it is non-destructive, permitting the same sample to be reused for other studies. Also, it is less expensive and faster compared to the use of an ICP-MS. The relatively high limit of detection of XRF for some elements is a disadvantage, and some potentially toxic elements may have been present in low concentrations, but were not measured (e.g., Ni and Co). This technique measures concentrations independent of the chemical state of an element.

Table 2:
Element concentrations median and range.
Element concentrations (ppm DW) of pelagic Sargassum spp. tissue collected from eight localities along the Mexican Caribbean coast between 2018 and 2019. The number of samples with readings above LOD are expressed in % of the total sample size (n = 63).

Notes:
LOD, Limit of detection.

Data analyses

The median of the five readings per element of each sample was calculated and used for further analysis. For each element, the readings below the limit of detection (<LOD; Table S1) were substituted with LOD/ 2–√ for calculation of summary statistics (Celo & Dabek-Zlotorzynska, 2010). Distributions (spread of data and the median values) of the fourteen most commonly found elements (e.g., Al, As, Ca, Cl, K, Mg, Mn, P, Rb, S, Si, Sr, Th and U) in sargasso tissue for each sampling locality are illustrated by dot plots. Differences in the concentration of elements among species and morphotypes were tested using non-parametric ANOVAs based on the Kruskal–Wallis rank procedure. We constructed a heatmap using the data from fourteen elements from Puerto Morelos (location 3, see Fig. 1) to visualize temporal differences in concentration of metals in seven different sampling periods between August 2018 and April 2019. Element concentration values were Z-score-transformed across sampling times and their values above and below the mean were used to generate the heatmap. The Z-value is a dimensionless quantity which is defined by the following equation (Larsen & Marx, 1986):
Z=(X−μ)∕σ
Where X represents an individual raw score that is to be standardized, σ is the standard deviation of the population, and μ is the mean of the population.

All analyses were done in R (R Core Team, 2019) using packages: dplyr (Wickham et al., 2019), ggplot2 (Wickham, 2009), gplots (Warnes et al., 2009), pgirmess (Giraudoux, 2013), reshape (Wickham, 2018), tidyr (Wickham & Henry, 2017), and RColorBrewer (Neuwirth, 2011) A reproducible record of all statistical analyses is available on GitHub (https://github.com/rerodriguezmtz/ElementsSar). This includes all underlying data and R code for all analyses.

Results

The most frequent elements in sargasso tissues, detected in 100% of the samples, were As, Ca, Cl, K, Mn, P, Rb, S, Si, Sr, Th, and U. They were followed in frequency by Mg (92.1% of samples) and Al (58.7% of samples) (Table 2). Other elements were found in fewer samples and they had median concentrations below the LOD: V (28.6% of samples), Zn (12.7% of samples), and Cu, Fe, Mo and Pb, present in 7.9% of samples (Table 2). Ba, Cd, Co, Cr, Ni, Ti, Y, and Zr remained below the LOD in all the samples (See Table S1 for LOD values). Some elements showed more than 5-fold difference between their minimal and maximal concentrations (ppm DW). For example, Cl showed 71.1-fold difference, K exhibited 23.1-fold difference, As had 7.2-fold difference, Si showed 6.5-fold difference and Ca exhibited 5.7-fold difference between their minimum and maximum values (Table 2). Concentrations of P, S and Sr showed the least inter-site variability and the concentrations of Al, As, Cl and K showed the most inter-site variability (Fig. 2).

Figure 2: Spatial variability in element concentrations.
Concentration of fourteen most frequent elements (ppm algal DW) in tissues of sargasso collected at eight sites along the Mexican Caribbean coast in 2018–2019. Note differences in scale of the Y-axis. Each dot corresponds to the median of the five XRF readings per sample. Color of the dot represents the sargasso species/morphotype. The horizontal black lines correspond to the median for each site. The dotted blue line corresponds to the limit of detection of the XRF equipment. A, Aluminum; B, Arsenic; C, Calcium; D, Chlorine; E, Potassium; F, Magnesium; G, Manganese; H, Phosphorus; I, Rubidium; J, Sulphur; K, Silicon; L, Strontium; M, Thorium; N, Uranium. Figure 1 and Table 1 have the site and sample details.

Among the potentially toxic elements, only As (median contents of 24–172 ppm DW) and Mn (median contents of 40–139 ppm DW) were present in all the samples (Table 2). Of all samples, 86% presented As concentrations above the maximum allowable concentration for seaweeds to be used as animal fooder under European regulations (40 ppm DW; EU, 2019), and 100% of the samples were above the maximum allowable concentration for agricultural soils in Mexico (22 ppm DW; NOM-147-SEMARNAT-SSA1-2004). Approximately 5% of our samples showed Cu concentrations above maximum tolerable level of dietary minerals for sheep (25 ppm DW) and cattle (100 ppm DW) (McDowell, 1992). Other potentially toxic elements (e.g., Mo, Pb and Zn) were detected in only 8–13% of the samples and they had median concentrations below the toxic limits for agricultural soils (see Table 2 and Table S2).

Concentrations of As, Ca, Cl, K, Mn, Rb and Si varied significantly among sargasso species/morphotypes (Fig. 2, Kruskal–Wallis test, p < 0.05; Table 3). As, Cl, K and Rb were significantly higher in Sargassum natans VIII compared to S. natans I. The concentrations of Ca and Si were significantly lower in S. natans VIII than in S. fluitans III and S. natans I. Similarly, the concentration of Mn was higher in S. natans I compared to S. fluitans III and S. natans VIII (Table 3). Contents of Al, Mg, P, S, Sr, Th and U did not vary significantly among species and morphotypes (KW, p > 0.05; Table 3). We did not compare the concentrations of Cu, Fe, Mo, Pb and Zn statistically among the species/morphotypes as their medians remained <LOD.

Table 3:
Elements concentrations in sargasso morphotypes.
Median and range (in parenthesis) of elements (ppm DW) in three sargasso species/morphotypes collected from eight localities along the Mexican Caribbean coast in 2018–2019. P values show summary of statistical analyses using Kruskal–Wallis H test (bold if significant) and the last column shows results of multiple comparison test.

Notes: LOD, limit of detection.

The concentrations of fourteen different elements (i.e., Al, As, Ca, Cl, K, Mg, Mn, P, Rb, S, Si, Sr, Th and U) in sargasso collected at Puerto Morelos in seven different sampling periods, from August 2018 to April 2019, showed considerable variability (Fig. 3). This inconsistent pattern indicates absence of any seasonal tendency in the elemental concentrations.

Figure 3: Temporal variability in element concentrations.
Variability in concentration of fourteen different elements (ppm DW) in sargasso collected at Puerto Morelos between August 2018 and April 2019. Z-score transformations were applied to values of each element across all the sampling periods and their intensities above and below the mean are represented on the heatmap by red and yellow colors, respectively, as shown on the color key bar.

Discussion

The sargasso tissues from the Mexican Caribbean had more As, Cu and Mn and less Cd, Cr, Pb and Zn compared to the chemical compositions of the algae biomass from Nigeria, Ghana and Dominican Republic (Table 4). Most striking was the high variability of element concentrations detected both in space (different sites along the coast) and time (different sampling months). This variability is likely partially due to the pelagic nature of the sargasso, as a result of increased uptake when exposed to areas rich in metals. It is unlikely that heavy metals were absorbed in near-shore waters of the Mexican Caribbean because this area lacks these elements in high concentrations, due to absence of major industrial, mining or heavy agricultural activities in the region. In addition, the absorption of metals by Sargassum thunbergii under experimental conditions was only clearly noticeable after ≥3 d exposure (Wu et al., 2010), whereas the residence time of sargasso in near-shore Mexican waters is usually in the order of hours when it is transported from the Yucatan Current towards the shore. Thus, the sargasso tissues likely acquired the heavy and trace elements before entering the Mexican coastal waters. Different contaminants are released into the ocean, some as point sources and others more continuous, in different parts across the North Equatorial Recirculation Region of the Atlantic Ocean (NERR) and the Wider Caribbean Region (as a result of long-range transport). Fernandez, Singh & Jaffé (2007) recognized the discharge of sewage, mineral extracts, fertilizer and pesticide used in the agricultural sector as the principal pollution sources. The pelagic masses of sargasso might have been exposed to these contaminants depending on its trajectory in the ocean. The metal sequestration also involves complex mechanisms of ion exchange, chelation, adsorption, and ion entrapment in polysaccharide networks of the algae (Volesky & Holan, 1995). This ion entrapment, in turn, depends on the affinity of some divalent metals to alginates (Haug, 1961), and pH of the seawater also influences absorption of metals (Davis, Volesky & Vieira, 2000). Alginates are often characterized by the proportion of mannuronic (M) and guluronic (G) acids present in the polymer (M:G ratio), which may vary among and within species. For example, Mn concentration was higher in S. natans I, whereas Ca and Si concentrations were higher in S. fluitans III and S. natans I, and the concentrations of As, Cl, K and Rb were higher in S. natans VIII than in S. natans I. Variations in the metal concentrations among the sargasso species and morphological forms may be explained by different concentrations in their tissues, but also by differences in calcifying epifauna, such as bryozoans, tube polychaeta, and crustose coralline algae (Weis, 1968; Huffard et al., 2014). Large differences in concentrations of Si (447–2,922 ppm DW) could be explained by different abundance of diatoms and silicoflagellates present in the samples (Takahashi & Blackwelder, 1992).

Table 4:
Element concentrations in different studies.
Comparison of element concentration in sargasso from the Mexican Caribbean coast and other studies in different parts of the world.

Notes:
a Oyesiku & Egunyomi, 2014 (mean and SD).
b Fernández et al., 2017 (range).
c Addico & De Graft-Johnson, 2016 (range).
d This study (range).

Sargasso samples from the Mexican Caribbean coast contained essential macro-elements for plants, like Ca (23,723–136,146 ppm DW), K (1,990–46,002 ppm DW), Mg (<2,915–13,662 ppm DW), P (228–401 ppm DW) and S (9,462–24,773 ppm DW), in addition to various micro-elements. Similar properties have been found in other Sargassum spp., making them adequate as complementary fertilizers as they enhance growth, seed germination and photosynthesis of crop plants on mineral-depleted soils (Sathya et al., 2010; Kumari, Kaur & Bhatnagar, 2013; El-Din, 2015). Some micro-elements found in sargasso from Mexico, such as Cu, Mn, Mo and Zn, are micronutrients in low concentrations, but they are potentially toxic when present in high concentrations. In this study, we detected the presence of Cu (<8–540 ppm DW) and Mo (<1–7 ppm DW) in 7.9% of the samples, Zn (<2–17 ppm DW) in 12.7% of the samples and Mn (40-139 ppm DW) in all the samples. Cu concentrations exceeded safely limits recommended for agricultural soils by several countries in 5% of the samples (see Table S2). Similarly, about 8% of our samples contained Mo concentrations above the maximum level established for agricultural soils by Canada (i.e., 2 ppm DW), but these were below the limits established by Austria and Poland (i.e., 10 ppm DW). Mn content was above 100 ppm DW in 22% of the samples, considered toxic for some plant species, but acceptable for others that can tolerate Mn up to 5,000 ppm DW (Howe, Malcolm & Dobson, 2004). Pb (<2–3 ppm DW) could be detected only in 7.9% of the samples, due to the limitation related to LOD of XRF analysis, and its concentration always remained below the toxic levels. Arsenic is of concern for the usages of sargasso as complementary fertilizer for crop plants. Limits of total As allowed for agricultural soils are between 15–50 ppm DW depending on the country (Table S2) (Belmonte-Serrato et al., 2010), thus, continuous application of sargasso (with total As between 24–172 ppm DW) may cause accumulation of As in the soils above allowable levels. High concentrations of As in soil may be toxic for the plants themselves, as it interferes with photosynthesis and other metabolic processes (Påhlsson, 1989; Ruiz Huerta & Armienta Hernández, 2012).

Sargasso could also be considered as animal fodder due to the presence of micro- and macro-elements, in addition to proteins, fibers and other components (Marín et al., 2009; Carrillo et al., 2012). However, approximately 86% of the samples had total As concentrations above the maximum level (40 ppm DW) allowable in Europe for animal feed materials derived from seaweed (EU, European Union). The toxicity of As depends on its chemical form, with inorganic As (trivalent state As III and pentavalent state As V) considered toxic (e.g., Yuan et al., 2007, Circuncisão et al., 2018), thus, even if total As concentrations are below 40 ppm DW, it is recommendable to carry out As speciation studies before using sargasso as animal fodder.

The (occasional) high contents of potentially toxic metals in sargasso is also a serious threat for the environment. The Mexican Caribbean coast has already received millions of tons of algae since late 2014. This accumulation over time, in addition to eutrophication and organic matter accumulation (Carruthers, van Tussenbroek & Dennison, 2005; Hernández-Terrones et al., 2011; Baker, Rodríguez-Martínez & Fogel, 2013; van Tussenbroek et al., 2017), is also a potential source of metal contamination for this region, even though levels of some potentially toxic elements like Cu, Mo, Zn, Mn and Pb were low. The sargasso removed from Mexican Caribbean beaches is presently deposited at abandoned limestone quarries, near the coast, without any treatment. The Yucatan Peninsula has a highly porous karst aquifer that is the only source of freshwater in the region. The pollutants from near surface deposits can easily infiltrate into the aquifer causing accumulation of As and other potentially toxic metals in the groundwater. Considering that water from the aquifer flows into the ocean through underground rivers, all these metals and excessive nutrients will eventually reach the marine environment (Carruthers, van Tussenbroek & Dennison, 2005; Metcalfe et al., 2011; Baker, Rodríguez-Martínez & Fogel, 2013). Prevention and mitigation measures are urgently needed to ensure that the massive influx of sargasso does not harm the coastal ecosystems and the tourism-based economy of countries located in the vicinity of the Great Atlantic Sargassum belt, including the Mexican Caribbean. The analyses of different specimens collected over longer periods and from different locations is required to obtain reliable information about metal contents in tissues.

Conclusion

In countries affected by the Great Atlantic Sargassum belt, the accumulation of decomposing sargasso on shores has harmed the coastal ecosystems, tourism-based economy and general human well-being. The Mexican Caribbean coast has received millions of tons of sargasso since late 2014, and our study concludes that the massive influx might contribute with potentially toxic elements to the coastal ecosystems, including the aquifer. We observed relatively higher values of As, Cu and Mn and lower values of Cd, Cr and Pb compared to similar studies in countries affected by the Sargassum belt. Cu, Mo, Zn, Mn and Pb were present in lower contents but their accumulation over time might be a potential source of contamination in this region. Total arsenic in most samples exceeded the limit established for usage as animal fodder in Europe and for agricultural soil in several countries. Further studies on As speciation are required before using sargasso in food industries to determine if it complies with guidelines of international institutions and organizations (i.e., FAO, WHO). Chemical analysis should also be conducted using other methodologies such as an ICP-MS, with better limit of detection, before evaluating sargasso usages in food, pharmaceutical and agricultural industries. Governments and industries have the financial strengths, as well as the moral and legal responsibilities, to carry out regular analyses of specimens collected over long periods and from different locations required for obtaining reliable information about metal contents in the tissues of sargasso due to its unpredictable variability.

Supplemental Information

Limits of Detection (LOD) of the analyzed elements in Niton FXL energy dispersive XRF (ppm = mg/kg) and Toxic metals and trace elements maximum levels permitted by different countries in agricultural soils (ppm = mg kg−1). nr: no reported

Additional Information and Declarations

Competing Interests : The authors declare there are no competing interests.

Author Contributions

Rosa E. Rodríguez-Martínez conceived and designed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, and approved the final draft.

Priyadarsi D. Roy, Nuria Torrescano-Valle and Nancy Cabanillas-Terán conceived and designed the experiments, performed the experiments, authored or reviewed drafts of the paper, and approved the final draft.

Silvia Carrillo-Domínguez, Ligia Collado-Vides, Marta García-Sánchez and Brigitta I. van Tussenbroek conceived and designed the experiments, authored or reviewed drafts of the paper, and approved the final draft.

Field Study Permissions
The following information was supplied relating to field study approvals (i.e., approving body and any reference numbers):

All surveys were conducted under permit PPD/DGOPA-116/14granted by SAGARPA (Agriculture, Natural Resources and Fisheries Secretariat) to Brigitta I. van Tussenbroek.

Data Availability
The following information was supplied regarding data availability:

Data is available at https://github.com/rerodriguezmtz/ElementsSar.

Funding
The authors received no funding for this work.

Acknowledgements

Special thanks to Elisa Vera Vázquez, for collecting sargasso samples from Puerto Morelos and Manta México Caribe A.C. for providing samples from Blue Waters and Isla Contoy. We also want to thank CEMIE-Oceano for the samples at Cozumel. Gabriela González López provided logistic help during fieldwork and in laboratory and Irma Gabriela Vargas-Martinez helped in XRF analysis. The authors claim no conflict of interest with this work.

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SOURCE: https://peerj.com/articles/8667/  Published February 26, 2020

 

FRANCE – Plan Sargasses II : le Gouvernement s’engage pour quatre ans auprès des collectivités locales

Pour pérenniser l’appui de l’État aux collectivités locales pour faire face au phénomène des sargasses, le Gouvernement vient d’adopter un second plan interministériel pour la période 2022-2025. Il est doté de près de 36 millions d’euros pour 4 ans. Ce budget traduit une augmentation de près de 30 % des financements de l’État.

Ce plan national prévoit 26 mesures pour mieux connaître, prévenir et lutter contre ce phénomène naturel. Il constitue un socle de priorités, de financements et de principes de gestion des sargasses, qui fera l’objet d’une déclinaison territoriale et opérationnelle avec les collectivités, en cours de concertation locale, dans les territoires les plus concernés (Martinique, Guadeloupe et Îles du Nord). Il permettra de mobiliser 3 millions d’euros, incluant des financements internationaux, pour la recherche amont consacrée à la compréhension et la prédiction de la prolifération des algues sargasses, et 3 millions d’euros pour des actions de recherche appliquée, en matière de valorisation des algues collectées notamment.

Les crédits nationaux, principalement gérés par les préfets et les agences régionales de santé, permettront d’appuyer les collectivités dans la durée, en particulier pour prendre en charge le ramassage des algues en mer comme à terre, et assurer leur transport et leur stockage. Les crédits à destination des collectivités ont ainsi été augmentés de 75 % dans ce second plan, et le taux de subvention porté à 50 % pour les actions qui étaient auparavant financées à 30 %.

Ce plan fait suite au premier plan national de prévention et de lutte contre les sargasses, lancé par l’État en octobre 2018. En octobre 2019, une conférence internationale a été organisée sous l’égide du Premier ministre, notamment pour mobiliser la recherche des différents pays concernés.

Le phénomène d’échouages des algues sargasses sur le littoral des Antilles et de la Guyane est un phénomène aux conséquences négatives très importantes, en matière sanitaire et environnementale ainsi que pour l’économie des îles concernées, notamment sur le secteur touristique. Il gagne au fil des années en nombre d’échouements et en intensité.

sargasses-martinique-guadeloupe-saintmartin-saintbarth-marie-galante-france

Contact(s)

EMAIL: secrétariat.presse@mer.gouv.fr

TEL : 01 44 49 85 24

TEL : 0155558424

 

 

Telecharger ICI le dossier de presse

Source : https://www.enseignementsup-recherche.gouv.fr/ du 17 mars 2022

Invita Comuna solidarense a segunda jornada de limpieza de sargazo

Invita Comuna solidarense a segunda jornada de limpieza de sargazo

Autoridades municipales convocaron a la sociedad en general a participar en la segunda jornada de limpieza de sargazo que se realizará este sábado 9 de abril, de 7 a 10 de la mañana, en las playas de las calles 10, 12, 14 norte, El Recodo y Punta Esmeralda.

De acuerdo con Lourdes Várguez Ocampo, directora de Zofemat Solidaridad, dicha jornada de limpieza se realizará cada sábado, y busca concientizar a la población de que todos podemos contribuir a mantener los arenales del municipio en buen estado.

Playa del Carmen – Sargazo

Agregó que, al mismo tiempo, se busca que “todos pongan su granito de arena”, para que se mantengan limpios los arenales durante este periodo vacacional, que a su vez transcurrirá en el marco de los primeros arribos atípicos de la temporada de sargazo.

Asimismo, recomendó a la ciudadanía interesada a acudir a los arenales con sombrero o gorra, así como con botellas de agua para mantenerse hidratados durante las actividades.

Sargazo Mexico Riviera Maya

Cabe mencionar que el pasado sábado se logró la convocatoria de alrededor de 500 trabajadores de diferentes secretarías del Ayuntamiento y ciudadanía en general y miembros de asociaciones civiles.

Fuente: INFOCARIBE 8 de Abril 2022