ABSTRACT In the last 30 years, the events of hydraulic drought in Guantánamo have intensified in such a way that they have affected the available water resources, abruptly interfering in the development of the main activities. The objective of this research is to evaluate the impacts of hydraulic drought in the "Caujerí Valley" by applying a synthetic index. A four-year time series was analyzed to characterize hydraulic drought events with categories of mild, moderate, intense and very intense, based on the application of an innovative hydraulic drought index, which corroborated its suitability and functionality. In addition, it demonstrated that from 2018 to 2021 the study area suffers the effects of a persistent drought with considerable damage.

RESUMEN En los últimos 30 años, los eventos de sequía hidráulica en Guantánamo se han intensificado de manera que han afectado los recursos hídricos disponibles, interfiriendo de manera brusca en el desarrollo de las principales actividades. El objetivo de la presente investigación es evaluar los impactos de la sequía hidráulica en el "Valle de Caujerí" mediante la aplicación de un índice sintético. Se analizó una serie temporal de cuatro años para caracterizar los eventos de sequía hidráulica con categorías de leves, moderadas, intensas y muy intensas, a partir de la aplicación de un novedoso Índice de sequía hidráulica, que corroboró la conveniencia y funcionalidad del mismo. Además, demostró que desde el 2018 hasta el 2021 el área de estudio sufre los efectos de una sequía persistente con daños considerables.

ABSTRACT The research is focused on studying the impact of the crisis caused by COVID-19 on family food security. Various epistemological positions of some researchers are analyzed, as well as the reality revealed in the current scenario. Economic and social inequalities are addressed in their context. The study is based on a systematic review with a critical approach based on the method of analysis and synthesis. The results reveal that the pandemic associated with COVID-19 has aggravated the current economic and social crisis, and has put family food security at risk in different contexts.

RESUMEN La investigación está centrada en el estudio de la repercusión de la crisis ocasionada por la COVID-19 en la seguridad alimentaria familiar. Son objeto de análisis diversas posiciones epistemológicas de algunos investigadores, así como la realidad develada en el escenario actual. Las desigualdades económicas y sociales se abordan en su contexto. El estudio se sustenta en una revisión sistemática con enfoque crítico sobre la base del método de análisis y síntesis. Los resultados permiten develar que la pandemia asociada a la COVID-19 ha agravado la actual crisis económica y social, y ha puesto en riesgo la seguridad alimentaria familiar en diferentes contextos.

ABSTRACT Trophic status of twenty-four water reservoirs of the eastern of Cuba was evaluated, classifying these reservoirs according to the eutrophication level. The average trophic state index (TSI) was calculated considering chlorophyll a, transparency and total phosphorus. A cluster analysis with TSI values allow to establish five eutrophic levels with specific ranges and attributes, modifying the classical Carlson criteria. The most eutrophic reservoirs were Chalóns and Camazán (level 4). It was confirmed direct relationship between eutrophic and cyanobacteria bloom occurrence, being the most contaminated those with higher risk. Toxic bloom-forming species were detected in Parada, Baraguá, La Yaya, Mícara, Bio and Guisa, Chalóns and Camazán, involving cyanobacteria like Synechocystis aquatilis, Cylindrospermopsis raciborskii, Oscillatoria sp., Microcystis aeruginosa, M. flos-aquae, M. panniformis,M. wesenbergii, Planktolyngbya limnetica, and Synechococcus sp.

RESUMEN El estado trófico de veinticuatro reservorios de agua del este de Cuba fue evaluado, clasificando estos según su nivel de eutrofización. El índice de estado trófico promedio (TSI) se calculó considerando la clorofila a, la transparencia y el fósforo total. Cinco niveles eutróficos con rangos y atributos específicos fueron establecidos modificando los criterios de Carlson luego de un análisis de clúster. Los reservorios más eutróficos fueron Chalóns y Camazán (nivel 4). Se confirmó la relación directa entre la aparición de floración eutrófica y de cianobacterias, siendo las más contaminadas las de mayor riesgo. Se detectaron especies tóxicas formadoras de flores en Parada, Baraguá, La Yaya, Mícara, Bio y Guisa, Chalóns y Camazán, involucrando cianobacterias como Synechocystis aquatilis, Cylindrospermopsis raciborskii, Microcystis aeruginosa, Oscillatoria sp, M. flos-aquae, M. panniformis, M. wesenbergii, Planktolyngbya limnetica, y Synechococcus sp.

We investigated the distribution of epiphytic macroalgae on the thalli of their hosts at eight localities along the southeastern coast of Cuba between June 2010 and March 2011. We divided he epiphytes in two groups according to their distribution on the host: those at the base of the thallus and those on its surface. We determining the dissimilarity between the zones and the species involved. We identified 102 taxa of epiphytic macroalgae. There were significant differences between the two zones. In 31 hosts, the number of epiphytes was higher on the surface of the thallus, whereas the number of epiphytes was higher at the thallus base in 25 hosts, and the epiphytes were equally distributed between the two zones in five hosts (R=−0.001, p=0.398). The mean dissimilarity between the two zones, in terms of the species composition of the epiphytic macroalgae, was 96.64%. Hydrolithon farinosum and Polysiphonia atlantica accounted for 43.76% of the dissimilarity. Among macroalgae, the structure of the thallus seems to be a determinant of their viability as hosts for epiphytes.