Loss of sediment associated with the removal of deposits of Sargassum spp. on the beaches of the Caribbean

La retirada de restos vegetales de Sargassum spp. depositados sobre la playa emergida constituyen una parte de la limpieza de playas en el Caribe. Estas gestiones realizadas a lo largo de las últimas décadas han dado lugar a la pérdida de superficies y volúmenes de playa y dunas. El estudio analiza los volúmenes de sedimento retirados mediante la limpieza de Sargassum spp. en 12 playas de México y República Dominicana, cuantificando el volumen total en 18.987,3 m3 , con un 61,23% de sedimento intercalado, equivalente a 9.872,36T de arena. Este tipo de gestión supone un impacto geomorfológico continuo con una importante pérdida de sedimento anual que afecta a la estabilidad del balance sedimentario del sistema playaPart of the cleaning of beaches in the Caribbean islands involves the removal of Sargassum spp. that remains deposited on the emerged beach and dunes. The study analyses the volumes of sediment removed with the Sargassum spp. at 12 beaches in México and the Dominican Republic, quantifying the volume of material removed at 18,987.3 m3 , of which an estimated 61.23 % (or 9,872.36 T) was sand. This kind of management involves a continuous geomorphological impact with an important loss of sediment that affects the stability of the sedimentary balance of the beach system

Analysis of the erosive effects of palms (Cocos nucifera L.) in the beach-dune systems of the Dominican Republic

Este estudio analiza el impacto de la distribución del coco (Cocos nucifera L.) en las playas de la República Dominicana y su relación con la erosión costera y la dinámica de los sistemas playa-duna. Se compararon 31 sistemas playa-duna utilizando 17 variables cualitativas para evaluar la influencia de las palmeras sembradas con fines agrícolas o turísticos en la morfología, ocupación antrópica y dinámica de las playas.Los resultados indican que las playas con palmeras sembradas con fines turísticos presentan mayor compactación, descalces y erosión, así como menor resiliencia en el sistema playa-duna. Estas playas también tienen una mayor presencia de complejos turísticos, limpieza mecánica y retirada de restos vegetales, lo que contribuye a la alteración del perfil y la vegetación propia de la playa. Las palmeras pueden actuar como aceleradores del flujo de olas, agravando la pérdida de sedimento y aumentando el riesgo de caída de las propias palmeras, lo que conlleva riesgos personales. Se concluye que la eliminación de los cocoteros y la restauración integral de las playas, incluyendo la recuperación de frentes dunares y vegetación asociada, son acciones necesarias para mejorar la estabilidad y dinámica de las costas dominicanas. Además, se sugiere la importancia de desarrollar estrategias de planificación y gestión que promuevan la conservación y restauración de los sistemas playa-duna en áreas turísticas y agrícolas.This study examines the impact of coconut (Cocos nucifera L.) distribution on the beaches of the Dominican Republic and its relationship with coastal erosion and beach-dune system dynamics.A total of 31 beach-dune systems were compared using 17 qualitative variables to assess the influence of palm trees planted for agricultural or touristic purposes on beach morphology, anthropic occupation, and dynamics. The results indicate that beaches with palm trees planted for touristic purposes exhibit higher compaction, slumping, and erosion, as well as lower resilience in the beach-dune system. These beaches also have a higher presence of tourist complexes, mechanical cleaning, and removal of vegetal debris, which contributes to the alteration of the beach profile and native vegetation. Palm trees can also act as wave flow accelerators, exacerbating sediment loss and increasing the risk of the palms themselves falling, which entails personal risks. It is concluded that the removal of coconut palms and comprehensive beach restoration, including the recovery of dune fronts and associated vegetation, are necessary actions to improve the stability and dynamics of Dominican coasts. Furthermore, the importance of developing planning and management strategies that promote the conservation and restoration of beach-dune systems in touristic and agricultural areas is suggested

Quantification of sediment loss due to the removal of berms of Thalassia testudinum on the beaches of the Caribbean: geomorphological effects

La retirada de restos vegetales de Thalassia testudinum depositados sobre la playa emergida, constituyen una parte de la limpieza de playas. Estas gestiones continuadas a lo largo de las últimas décadas han dado lugar a la pérdida de superficies y volúmenes de playa. El estudio analiza los volúmenes de sedimento retirados mediante la retirada de bermas de Thalassia testudinum en 11 playas de 4 países del Caribe, cuantificando el volumen total en 35.837,7 m3 , con un 89,05 % de sedimento intercalado, equivalente a 32.846,75 t de arena. Este tipo de gestión supone un impacto geomorfológico continuo con una importante pérdida de sedimento anual que afecta a la estabilidad del balance sedimentario del sistema playa.Part of the cleaning of beaches in the Caribbean islands has been focused on the removal of the remains of Thalassia testudinum deposited on the emerged beach. The study analyses the volumes of sediment extracted through the removal of Thalassia testudinum berms from 11 beaches distributed throughout 4 Caribbean countries, quantifying the total volume of material removed at 35,837.7m3 , of which an estimated 89.05% is interspersed sand, equivalent to 32,846.75 t of sand. This kind of management involves a continuous geomorphological impact with an important loss of sediment that affects the stability of the sedimentary balance of the beach system

First record of the presence of blocks associated with extreme events on the southern coast of Hispaniola (Dominican Republic)

Se registra por primera vez en la isla caribeña de la Española, República Dominicana, la presencia de bloques de grandes dimensiones ubicados sobre la costa rocosa y relacionados con eventos extremos. Se trata de bloques dispersos, algunos con imbricación, y ubicados en la costa de Sardinilla (San Pedro de Macorí, la Romana), S de República Dominicana. El registro amplía los estudios de bloques en el Caribe y abre la puerta a nuevas investigaciones relacionadas con eventos de ciclones y/o tsunamis en los países de Haití y República Dominicana.The presence of large boulders located on a rocky coast and related to extreme events is registered for the first time on the Caribbean island of Hispaniola. These are scattered boulders, some overlapping, found on the coast of Sardinilla (San Pedro de Macorí la Romana), in the south of the Dominican Republic. The discovery expands boulders studies in the Caribbean and opens the door to new research related to cyclone and/or tsunami events in Haiti and the Dominican Republic

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Cuantificación de la pérdida de sedimento por la retirada de depósitos de Thalassia testudinum en las playas del Caribe: efectos geomorfológicos

Part of the cleaning of beaches in the Caribbean islands has been focused on the removal of the remains of Thalassia testudinum deposited on the emerged beach. The study analyses the volumes of sediment extracted through the removal of Thalassia testudinum berms from 11 beaches distributed throughout 4 Caribbean countries, quantifying the total volume of material removed at 35,837.7m3, of which an estimated 89.05% is interspersed sand, equivalent to 32,846.75 t of sand. This kind of management involves a continuous geomor-phological impact with an important loss of sediment that affects the stability of the sedimentary balance of the beach system.La retirada de restos vegetales de Thalassia testudinum depositados sobre la playa emergida, constituyen una parte de la limpieza de playas. Estas gestiones continuadas a lo largo de las últimas décadas han dado lugar a la pérdida de superficies y volúmenes de playa. El estudio analiza los volúmenes de sedimento retirados mediante la retirada de bermas de Thalassia testudinum en 11 playas de 4 países del Caribe, cuantificando el volumen total en 35.837,7 m3, con un 89,05 % de sedimento intercalado, equivalente a 32.846,75 t de arena. Este tipo de gestión supone un impacto geomorfológico continuo con una importante pérdida de sedimento anual que afecta a la estabilidad del balance sedimentario del sistema playa