RESUMEN
The most severe drought of this century in the Amazon rainforest, which was caused by El Niño, occurred from 2015 to 2016. With a focus on the ecophysiology of the regrowth of the Brazil nut tree, Bertholletia excelsa, it was investigated how the progression of the drought of 2015-2016 affected the physiological traits of the coppice regrowth of B. excelsa. The experiment was carried out in a ten-year-old plantation of Brazil nut trees, which had been subjected to thinning and coppice regrowth two years earlier. In the sprouts grown on the stumps of cut trees, the following treatments were applied: (T1) thinning to one sprout per stump; (T2) thinning to two sprouts per stump, and (T3) maintenance of three sprouts per stump. Thinning treatments did not alter the growth and ecophysiological traits of the Brazil nut tree sprouts, though the phosphorus content of the leaves was higher in T1. However, the progression of the drought in 2015-2016 negatively affected the growth (height) and gas exchange of sprouts of all treatments. In addition, an increase of around 37% was observed in the intrinsic wateruse efficiency. Concerning photochemical performance, no alterations were observed. Therefore, drought stress promoted a negative effect on sprout growth and affected traits related to the photosynthesis of the B. excelsa sprouts independently of the number of sprouts per stump.(AU)
A seca mais severa deste século na floresta amazônica, causada por El Niño, ocorreu de 2015 a 2016. Com foco na ecofisiologia da rebrota da castanheira da Amazônia, foi investigado como a progressão da seca de 2015-2016 afetou as características fisiológicas das rebrotas de uma talhadia de B. excelsa. O experimento foi realizado em uma plantação de castanheiras com dez anos, a qual havia sido submetida a um desbaste e rebrota de talhadia dois anos antes. Nas rebrotas crescidas sobre os tocos das árvores cortadas foram aplicados os seguintes tratamentos: (T1) desbrota para manter um broto por cepa; (T2) desbrota para manter dois brotos por cepa; e (T3) manutenção de três brotos por cepa. Os tratamentos de desbrota não alteraram o crescimento e as características ecofisiológicas dos brotos da castanheira, exceto para o teor foliar de fósforo, que foi maior em T1. Porém, a progressão da seca em 2015-2016 afetou negativamente o crescimento em altura e as trocas gasosas dos brotos de todos os tratamentos. Além disso, foi observado um aumento de cerca de 37% na eficiência intrínseca do uso da água. Quanto ao desempenho fotoquímico, não foram observadas alterações. Portanto, o estresse hídrico promoveu efeito negativo no crescimento da brotação e afetou características relacionadas à fotossíntese das brotações de B. excelsa, independentemente do número de brotações por cepa.(AU)
Asunto(s)
Estructuras de las Plantas/crecimiento & desarrollo , Bertholletia/crecimiento & desarrollo , Bertholletia/fisiología , Brasil , El Niño Oscilación del Sur/efectos adversosRESUMEN
Stable isotope analyses, particularly of carbon (δ13C) and nitrogen (δ15N), are used to investigate ecological relationships among species. For marine predators, research has shown the main factors influencing their intra-specific and intra-individual isotopic variation are geographical movements and changes in the composition of diet over time. However, as the differences seen may be the result of changes in the prey items consumed, a change in feeding location or the combination of both, knowledge of the temporal and spatial consistency in the isotopic values of prey becomes crucial for making accurate inferences about predator diets. This study used an abundant marine predator, the Australasian gannet (Morus serrator), as prey sampler to investigate the annual variation in fish and squid prey isotope values over a four-year period (2012-2015) and the geographic variation between two sites with contrasting oceanographic conditions. Significant inter-annual variation was observed in δ13C and/or δ15N values of five of the eight prey species analysed. The strongest inter-annual variation in both δ13C and δ15N values occurred in 2015, which coincided with a strong El Niño-Southern Oscillation (ENSO). This may suggest a temporal fluctuation in the geographic source of prey or the origin of their nutrients. These results suggest that it is important to consider the potential significant differences in isotopic values within the prey assemblages that predators consume. This is important to improve the interpretation of marine predator isotope results when determining the influence of environmental variability on their diets.
Asunto(s)
Organismos Acuáticos/metabolismo , Conducta Alimentaria/fisiología , Isótopos/análisis , Animales , Australia , Carbono/metabolismo , Dieta , El Niño Oscilación del Sur/efectos adversos , Conducta Alimentaria/clasificación , Cadena Alimentaria , Geografía , Nitrógeno/metabolismo , Nutrientes/metabolismo , Oceanografía , Conducta Predatoria/fisiología , Alimentos Marinos , Análisis Espacio-TemporalRESUMEN
The past 40 years in Southeast Asia have seen about 50% of lowland rainforests converted to oil palm and other plantations, and much of the remaining forest heavily logged. Little is known about how fragmentation influences recovery and whether climate change will hamper restoration. Here, we use repeat airborne LiDAR surveys spanning the hot and dry 2015-16 El Niño Southern Oscillation event to measure canopy height growth across 3,300 ha of regenerating tropical forests spanning a logging intensity gradient in Malaysian Borneo. We show that the drought led to increased leaf shedding and branch fall. Short forest, regenerating after heavy logging, continued to grow despite higher evaporative demand, except when it was located close to oil palm plantations. Edge effects from the plantations extended over 300 metres into the forests. Forest growth on hilltops and slopes was particularly impacted by the combination of fragmentation and drought, but even riparian forests located within 40 m of oil palm plantations lost canopy height during the drought. Our results suggest that small patches of logged forest within plantation landscapes will be slow to recover, particularly as ENSO events are becoming more frequent.
Asunto(s)
El Niño Oscilación del Sur/efectos adversos , Bosques , Árboles , Clima Tropical , Arecaceae , Asia Sudoriental , Borneo , Cambio Climático , Sequías , Ecología , Humanos , Malasia , Hojas de la Planta , Bosque LluviosoRESUMEN
We present a time series of 13 years (2003-2016) of continuous monthly data on the prevalence and mean abundance of the trematode Oligogonotylus mayae for all the hosts involved in its life cycle. We aimed to determine whether annual (or longer than annual) environmental fluctuations affect these infection parameters of O. mayae in its intermediate snail host Pyrgophorus coronatus, and its second and definitive fish host Mayaheros urophthalmus from the Celestun tropical coastal lagoon, Yucatan, Mexico. Fourier time series analysis was used to identify infection peaks over time, and cross-correlation among environmental forcings and infection parameters. Our results suggest that the transmission of O. mayae in all its hosts was influenced by the annual patterns of temperature, salinity and rainfall. However, there was a biannual accumulation of metacercarial stages of O. mayae in M. urophthalmus, apparently associated with the temporal range of the El Niño-Southern Oscillation (five years) and the recovery of the trematode population after a devasting hurricane. Taking O. mayae as an example of what could be happening to other trematodes, it is becoming clear that environmental forcings acting at long-term temporal scales affect the population dynamics of these parasites.
Asunto(s)
Cíclidos/parasitología , Caracoles/parasitología , Trematodos/parasitología , Animales , El Niño Oscilación del Sur/efectos adversos , Interacciones Huésped-Parásitos , Estadios del Ciclo de Vida , Metacercarias/crecimiento & desarrollo , México/epidemiología , Dinámica Poblacional , Prevalencia , Estaciones del Año , Temperatura , Clima TropicalRESUMEN
Childhood diarrheal disease causes significant morbidity and mortality in low and middle-income countries, yet our ability to accurately predict diarrhea incidence remains limited. El Niño-Southern Oscillation (ENSO) has been shown to affect diarrhea dynamics in South America and Asia. However, understanding of its effects in sub-Saharan Africa, where the burden of under-5 diarrhea is high, remains inadequate. Here we investigate the connections between ENSO, local environmental conditions, and childhood diarrheal disease in Chobe District, Botswana. Our results demonstrate that La Niña conditions are associated with cooler temperatures, increased rainfall, and higher flooding in the Chobe region during the rainy season. In turn, La Niña conditions lagged 0-5 months are associated with higher than average incidence of under-5 diarrhea in the early rainy season. These findings demonstrate the potential use of ENSO as a long-lead prediction tool for childhood diarrhea in southern Africa.
Asunto(s)
Diarrea Infantil/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , El Niño Oscilación del Sur/efectos adversos , Infecciones por Rotavirus/epidemiología , Vacunas contra Rotavirus/administración & dosificación , Rotavirus/inmunología , Botswana/epidemiología , Preescolar , Frío/efectos adversos , Diarrea Infantil/prevención & control , Diarrea Infantil/virología , Brotes de Enfermedades/prevención & control , Seguimiento de Parámetros Ecológicos/estadística & datos numéricos , Humanos , Incidencia , Lactante , Recién Nacido , Lluvia , Infecciones por Rotavirus/prevención & control , Infecciones por Rotavirus/virologíaRESUMEN
The dynamics of dengue transmission are multifactorial and involve socioeconomic, ecological, and environmental aspects, the latter being closely related to local climatic conditions that affect the vector's reproductive cycle. Climate depends in turn on tropical oceanic mechanisms such as phases of El Niño/La Niña over the Pacific. The study contributes to this discussion and reports on the correlations between the Multivariate ENSO Index (MEI) in the Pacific and the number of reported dengue cases in seven state capitals in the Brazilian Amazon from 2001 to 2012. The study also analyzes the seasonality pattern (quarterly mean values) in dengue cases throughout the region. Evidence that El Niño/La Niña causes a decrease versus increase in the local rainfall pattern is consistent with the lower versus higher number of reported dengue cases in most of the state capitals in the Amazon, a result proven by the statistically significant negative correlations seen in Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) and Palmas (Tocantins). The 12-years means (2001-2012) revealed the presence of pronounced seasonality in dengue incidence in the majority of the state capitals, with sharp peaks from January to March [Rio Branco (Acre), Manaus, Belém and Palmas] and from April to June (São Luís), corresponding to 50-70% of the annual total. State capitals farther north [Boa Vista (Roraima) and Macapá (Amapá)] showed dengue reporting in all quarters of the year, with no pronounced seasonality.
A dinâmica de transmissão da dengue é multifatorial e envolve aspectos socioeconômicos, ecológicos e ambientais, sendo este último intimamente relacionado às condições climáticas locais que interferem no ciclo reprodutivo dos vetores da doença. Por sua vez, o clima é dependente dos mecanismos oceânicos tropicais, a exemplo das fases de El Niño/La Niña sobre o Pacífico. O presente trabalho contribui com esta temática e reporta as correlações entre o índice MEI (Multivariate ENOS Index) do Pacífico e o número de casos notificados de dengue em sete capitais da Amazônia brasileira, no período de 2001 a 2012. Além disso, investiga-se o padrão de sazonalidade (médias trimestrais) dos casos de dengue ao longo da região. As evidências de que o fenômeno El Niño/La Niña provoca redução/aumento no padrão pluviométrico local é consistente com o número menor/maior de casos notificados de dengue na maior parte das capitais amazônicas, cujo resultado foi comprovado pelas correlações negativas estatisticamente significantes encontradas para Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) e Palmas (Tocantins). As médias dos 12 anos (2001/2012) revelaram a presença de sazonalidade pronunciada na incidência de dengue na maioria das capitais, com picos acentuados de janeiro a março [Rio Branco (Acre), Manaus, Belém e Palmas] e de abril a junho (São Luís), correspondendo em torno de 50% a 70% do total anual. As localidades mais ao norte [Boa Vista (Roraima) e Macapá (Amapá)] revelaram registro da dengue ao longo de todos os trimestres do ano, não apresentando sazonalidade acentuada.
La dinámica de transmisión del dengue es multifactorial e implica aspectos socioeconómicos, ecológicos y ambientales, estando estos últimos íntimamente relacionados con las condiciones climáticas locales que interfieren en el ciclo reproductivo de los vectores de la enfermedad. A su vez, el clima depende de los mecanismos oceánicos tropicales, como por ejemplo las fases de El Niño/La Niña sobre el Pacífico. El presente trabajo contribuye a esta temática e informa sobre las correlaciones entre el índice MEI (Multivariate ENOS Index) del Pacífico y el número de casos notificados de dengue en siete capitales de la Amazonia brasileña durante el período de 2001 a 2012. Además, se investiga el patrón de estacionalidad (medias trimestrales) de los casos de dengue a lo largo de la región. Las evidencias de que el fenómeno El Niño/La Niña provoca reducción/aumento en el patrón pluviométrico local es consistente con el número menor/mayor de casos notificados de dengue en la mayor parte de las capitales amazónicas, cuyo resultado se comprobó por las correlaciones negativas estadísticamente significativas encontradas en Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) y Palmas (Tocantins). Las medias de los doce años (2001/2012) revelaron la presencia de estacionalidad pronunciada en la incidencia de dengue en la mayoría de las capitales, con picos acentuados de enero a marzo [Rio Branco (Acre), Manaus, Belém y Palmas] y de abril a junio (São Luís), correspondiendo en torno del 50 al 70% del total anual. Las localidades más al norte [Boa Vista (Roraima) y Macapá (Amapá)] revelaron registro del dengue a lo largo de todos los trimestres del año, no presentando una estacionalidad acentuada.
Asunto(s)
Dengue/epidemiología , El Niño Oscilación del Sur/efectos adversos , Animales , Brasil/epidemiología , Dengue/transmisión , Vectores de Enfermedades , Humanos , Incidencia , Estaciones del AñoRESUMEN
OBJECTIVE: The aim of this study was to identify regulations that were established and implemented as an emergency disaster response to intense rain and floods generated by the El Niño coastal phenomenon. METHODS: A search was conducted for the legal norms approved and published between December 1, 2016 and December 31, 2017, in El Peruano, Peru's official newspaper. Twenty legal norms involved disaster emergency response, rehabilitation, and the reconstruction of the affected regions. RESULTS: Forty-six legal norms were identified, of which 41% were aimed at the declaration of emergencies and alerts, 22% to facilitate the management of economic resources, and 13% for coordination actions. Sixty-two percent of the approved standards were set for the regional level, 22% for the national level, 7% for the municipal level, and the remaining 10% corresponded with more than 1 level of government. CONCLUSIONS: The actions during and after the El Niño coastal phenomenon required the approval of standards included in the legal framework of Peru's disaster risk management, as well as a large number of unforeseen standards to address existing regulatory gaps and specific problems that occurred during this natural disaster.
Asunto(s)
Atención a la Salud/tendencias , Planificación en Desastres/legislación & jurisprudencia , El Niño Oscilación del Sur/efectos adversos , Atención a la Salud/legislación & jurisprudencia , Desastres/estadística & datos numéricos , Humanos , Innovación Organizacional , PerúRESUMEN
Objetivo: Describir los conocimientos y prácticas sobre las medidas preventivas de dengue en los pobladores de ciudad afectada por epidemia del dengue posfenómeno de El Niño costero, Perú, 2018, y comparar los conocimientos con el cuestionario ENAPRES 2016. Métodos: se realizó un estudio descriptivo transversal en el que se recolectó información mediante dos cuestionarios consecutivos. La muestra se obtuvo con nivel de confianza del 95 por ciento, proporción esperada 29,1 por ciento, precisión de 4,5 por ciento, y población de 8 210 casas, y considerando pérdidas será una muestra de 380. Resultados: La población estuvo constituida principalmente por mujeres (73,7 por ciento), con edad promedio de 42,5 años, 41,8 por ciento secundaria completa, 54,5 por ciento amas de casa. El medio de obtención de información más frecuente fue el centro de salud (48,7 por ciento). El 21,1 por ciento manifestó conocer la enfermedad, el 75 por ciento conocía la transmisión por zancudo y el 86,1 por ciento que este se reproduce en aguas estancadas. Además, 69,2 por ciento reconoció los síntomas de la enfermedad. El 9,7 por ciento señaló medidas para eliminar criaderos, mientras el 20,5 por ciento reconoció medidas para evitar ser picado. El 83,2 por ciento manifestó conocer el abate y su uso. Los síntomas más identificados por la población fueron fiebre, dolor de cabeza, dolor de huesos y/o articulaciones y dolor muscular. Según la comparación realizada con el cuestionario ENAPRES 2016, hubo aumento de conocimiento de los signos de alarma (sangrado, náuseas y vómitos). Conclusiones: Los conocimientos en prevención de dengue fueron escasos y las prácticas observadas resultaron insuficientes en la población de Tumán, pero mejoró el conocimiento en algunas medidas de prevención con respecto a 2016(AU)
Objective: Describe the knowledge and practices regarding dengue prevention measures among the residents of a Peruvian city affected by a dengue epidemic following the 2018 Coastal Child, and compare the knowledge using the ENAPRES 2016 questionnaire. Methods: A descriptive cross-sectional study was conducted in which information was collected by means of two consecutive questionnaires. The sample was obtained with a 95 percent confidence interval, a 29.1 percent expected proportion, 4.5 percent precision and a population of 8 210 households, and considering losses will be a sample of 380. Results: The population was predominantly female (73.7 percent), with a mean age of 42.5 years, 41.8 percent complete secondary schooling, and 54.5 percent housewives. The source of information most commonly used was the health center (48.7 percent). 21.1 percent reported knowing about the disease, 75 percent knew that it was transmitted by mosquitoes, and 86.1 percent knew that mosquitoes reproduce in stagnant water. In addition, 69.2 percent recognized the symptoms of the disease. 9.7 percent referred to measures to eliminate breeding sites, and 20.5 percent to measures to avoid being bitten. 83.2 percent stated they knew about temefos and its use. The symptoms most commonly identified by the population were fever, headache, bone and/or joint pain, and muscle pain. According to the comparison made with the ENAPRES 2016 questionnaire, there was an increase in knowledge about alarm signs (bleeding, nausea and vomiting). Conclusions: Knowledge about dengue prevention was scarce and the practices observed among the population of Tumán were insufficient, but improvement was observed in the knowledge about some prevention measures with respect to 2016(AU)
Asunto(s)
Humanos , Masculino , Femenino , Conocimientos, Actitudes y Práctica en Salud , El Niño Oscilación del Sur/efectos adversos , Dengue/prevención & control , Perú , Epidemiología Descriptiva , Estudios TransversalesRESUMEN
Forecast-based drought early warning/early action has been hampered by both inadequate decision-making frameworks and a lack of appropriate funding mechanisms. Rural communities in Nicaragua and Ethiopia that have participated in resilience-building interventions of varying durations demonstrate the value of community-based actions informed by early warning, forecasts and drought management advice, both before and during the agricultural season. While drought affected all crops negatively, participants were better able to mitigate impacts, were more organised in accessing relief and recovered more effectively. These results are consistent with other research on the cost/benefit of anticipatory actions, use of climate services and appropriate drought management advice. They also confirm the importance of embedding short-term early action in long-term resilience-building. Despite this, formal systems, national and local, remain essentially unimplemented. Systems being developed at global level now need to be operationalised and translated into effective local drought management standard operating procedures for the most vulnerable.
Asunto(s)
Planificación en Desastres/organización & administración , Sequías , El Niño Oscilación del Sur/efectos adversos , Agricultura , Etiopía , Predicción , Humanos , Nicaragua , Población Rural , Estaciones del AñoRESUMEN
Structural complexity underpins the ecological functioning of coral reefs. However, rising ocean temperatures and associated coral bleaching threaten the structural integrity of these important ecosystems. Despite the increased frequency of coral bleaching events, few studies to date have examined changes in three-dimensional (3D) reef structural complexity following severe bleaching. The influence of local stressors on reef complexity also remains poorly understood. In the wake of the 2015-2016 El Niño-induced mass coral bleaching event, we quantified the effects of severe heat stress on 3D reef structural complexity across a gradient of local human disturbance. Using Structure-from-Motion photogrammetry we created 3D reconstructions of permanent reef plots and observed substantial declines in reef structural complexity, measured as surface rugosity and terrain ruggedness, and a detectable loss of habitat volume one year after the bleaching event. 3D reef complexity also declined with increasing levels of human disturbance, and with decreasing densities of branching and massive corals. These findings improve our understanding of the effects of local and global stressors on the structural foundation of coral reef ecosystems. In the face of accelerating climate change, mitigating local stressors may increase reef structural complexity, thereby heightening reef resilience to future bleaching events.
Asunto(s)
Antozoos/química , Ecosistema , Agua de Mar/química , Simbiosis/fisiología , Animales , Antozoos/fisiología , Cambio Climático , Arrecifes de Coral , El Niño Oscilación del Sur/efectos adversos , Peces/metabolismo , Humanos , Dinámica Poblacional , TemperaturaRESUMEN
Introducción: En la actualidad, el dengue persiste como un problema latente para la salud pública en nuestro país; se debe tener en cuenta también que los casos de dengue han presentado una tendencia creciente en los últimos 5 años, en 2017 una cifra de 76 093 casos (3.03 veces más casos en relación con 2016), y 93 muertes, la mayor cifra en los últimos 5 años. Objetivo: Describir el perfil clínico, epidemiológico y geográfico del dengue en la Red EsSalud Lambayeque 2017, durante El Niño Costero. Material y métodos: Pacientes captados por sistema de vigilancia epidemiológica que cuentan con ficha epidemiológica con diagnóstico clínico de dengue de todas las edades, ambos sexos, atendidos en la red asistencial EsSalud-Lambayeque durante el fenómeno El Niño Costero. Se utilizó estadística descriptiva con cálculo de frecuencias absolutas y relativas para las variables cualitativas y media con desviación estándar para las cuantitativas y software libre QGis 2.14 para georreferenciación. Resultados: La edad fue 7.2 + 20.4 años, 27,9 por ciento procedentes de Chiclayo, 52,9 por ciento fueron mujeres, 77 por ciento presentaron dengue sin signos de alarma, 1,5 por ciento fallecidos. De los 874 casos, 335 (38,3 por ciento ) casos fueron positivos 213 (63,5 por ciento ) por laboratorio. La clínica más frecuente fue fiebre, cefalea, artralgia y mialgia. El signo de alarma más frecuente fue disminución de plaquetas. Conclusiones: El dengue afectó en mayor frecuencia a la población adulta, femenina, procedente de Chiclayo; clínicamente sin signos de alarma(AU)
Introduction: At present, dengue fever persists as a latent problem for public health in our country. It should also be borne in mind that the cases of dengue fever have presented a growing trend during the last 5 years, with a number of 76 093 cases in 2017 (3.03 times more cases with respect to the year 2016); and 93 deaths, which represents the highest figure in the last 5 years. Objective: To describe the clinical, epidemiological and geographical profile of dengue fever in the EsSalud Lambayeque Network 2017, during El Niño Costero Phenomenon. Material and Methods: Patients of all ages and both sexes with an epidemiological record of a clinical diagnosis of dengue identified by the epidemiological surveillance system, in the EsSalud-Lambayeque Health Care Network, during El Niño Costero Phenomenon. Descriptive statistics with calculation of absolute and relative frequencies for qualitative variables and mean with standard deviation for quantitative and free software QGis 2.14 for georeferencing. Results: The age was 7.2 + 20.4 years, 27.9 percent from Chiclayo, 52.9 percent were women; 77 percent had dengue without warning signs, 1.5 percent died. Of the 874 cases, 335 ones (38.3 percent) were positive, and 213 (63.5 percent) were diagnosed from reference laboratory. The most frequent clinical symptoms and signs were fever, headache, arthralgia and myalgia. The most frequent alarm sign was decrease in platelet. Conclusions: Dengue fever affected the adult female population from Chiclayo more frequently; presenting no clinical warning signs(AU)
Asunto(s)
Humanos , Femenino , El Niño Oscilación del Sur/efectos adversos , Dengue/etiología , Dengue/transmisión , Perfil de Salud , Epidemiología Descriptiva , Estudios Transversales , Estudio ObservacionalRESUMEN
Summer days with extremely hot temperatures in Taiwan have been increasing for the past few decades, and this continuing trend is expected to worsen heat-related mortality. To mitigate the corresponding health impacts, in this study, we developed a statistical state-space model to predict the number of extremely hot days in June-September for the next year. Based on historical data from 1951 to 2017, we estimated the climate change trend after adjusting for the nonlinear lagged effect of the Niño 3.4 index. We then developed a predictive state-space model using these two primary factors and adjusting for residual autocorrelations. Validation results comparing the extremely hot days observed over 2015-2017 with predictions showed that 86% of the average prediction errors were within 4â¯days of the observations. To assess the health impacts, we applied the model to the projection of heat-attributable mortality (AM) in 2018 by adopting a comparative risk assessment (CRA) approach with the reference period of 2001-2010. The results showed that the Taipei metropolitan area in northern Taiwan is the most affected region with AM of 1501 deaths from all-causes, followed by Taichung in central Taiwan with 490 deaths. The prediction model and the CRA projection provide both a tool and guidance for public health administrators to address the imminent threat posed by climate change.
Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Cambio Climático , El Niño Oscilación del Sur , Calor Extremo/efectos adversos , Enfermedades Respiratorias/mortalidad , Enfermedades Cardiovasculares/etiología , El Niño Oscilación del Sur/efectos adversos , Predicción , Humanos , Modelos Teóricos , Enfermedades Respiratorias/etiología , Medición de Riesgo/métodos , Estaciones del Año , Taiwán/epidemiologíaRESUMEN
Climate change is expected to exacerbate upwelling intensity and natural acidification in Eastern Boundaries Upwelling Systems (EBUS). Conducted between January-September 2015 in a nearshore site of the northern Humboldt Current System directly exposed to year-round upwelling episodes, this study was aimed at assessing the relationship between upwelling mediated pH-changes and functional traits of the numerically dominant planktonic copepod-grazer Acartia tonsa (Copepoda). Environmental temperature, salinity, oxygen, pH, alkalinity, chlorophyll-a (Chl), copepod adult size, egg production (EP), and egg size and growth were assessed through 28 random oceanographic surveys. Agglomerative clustering and multidimensional scaling identified three main di-similitude nodes within temporal variability of abiotic and biotic variables: A) "upwelling", B) "non-upwelling", and C) "warm-acid" conditions. Nodes A and B represented typical features within the upwelling phenology, characterized by the transition from low temperature, oxygen, pH and Chl during upwelling to higher levels during non-upwelling conditions. However, well-oxygenated, saline and "warm-acid" node C seemed to be atypical for local climatology, suggesting the occurrence of a low frequency oceanographic perturbation. Multivariate (LDA and ANCOVA) analyses revealed upwelling through temperature, oxygen and pH were the main factors affecting variations in adult size and EP, and highlighted growth rates were significantly lower under node C. Likely buffering upwelling pH-reductions, phytoplankton biomass maintained copepod reproduction despite prevailing low temperature, oxygen and pH levels in the upwelling setting. Helping to better explain why this species is among the most recurrent ones in these variable yet productive upwelling areas, current findings also provide opportune cues on plankton responses under warm-acid conditions, which are expected to occur in productive EBUS as a consequence of climate perturbations.
Asunto(s)
Copépodos/fisiología , El Niño Oscilación del Sur/efectos adversos , Fitoplancton/crecimiento & desarrollo , Animales , Biomasa , Clorofila A/análisis , Cambio Climático , Copépodos/crecimiento & desarrollo , Ecosistema , Concentración de Iones de Hidrógeno , Plancton/crecimiento & desarrollo , Dinámica Poblacional , Salinidad , Estaciones del Año , TemperaturaRESUMEN
INTRODUCTION: Leptospirosis is a zoonotic disease caused by a bacteria of the genus Leptospira. Climate is key in order to understand leptospirosis dynamics. El Niño Southern Oscillation is the main modulator of climate in Colombia. Our goal was to analyze the changes that occurred in number of cases and incidence rate of leptospirosis during La Niña and El Niño episodes in Colombia at three spatial scales in the period between 2007 and 2015. METHODOLOGY: A cross-sectional retrospective study was performed. DATA ANALYSIS: correlation and lagged cross correlation between time series of Oscillation Niño Index and time series of standardized number of leptospirosis cases; construction of annual cycle of leptospirosis; comparison of changes of number of cases between Neutral, periods with El Niño and Neutral periods with La Niña. RESULTS: At the national level, monthly number of cases raised a 25% during La Niña and decreased of 17% during El Niño. At departmental level, increase of cases in both phases of ENSO, depending on the location in the country, was found. At the municipal level, 17 have a rise in the number of cases during La Niña months. Of those, seven presented also an increase of cases during El Niño months and eight have a significant negative correlation with ONI. CONCLUSIONS: In Colombia, there exists a relationship between leptospirosis and the excess and lack of rainfall related with ENSO. The contrasting results from each spatial scale, reinforce that leptospirosis is a multidimensional disease with high complex interactions among its determinants.
Asunto(s)
El Niño Oscilación del Sur , Leptospirosis/epidemiología , Colombia/epidemiología , Estudios Transversales , Sequías , El Niño Oscilación del Sur/efectos adversos , Humanos , Incidencia , Lluvia , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Resumo: A dinâmica de transmissão da dengue é multifatorial e envolve aspectos socioeconômicos, ecológicos e ambientais, sendo este último intimamente relacionado às condições climáticas locais que interferem no ciclo reprodutivo dos vetores da doença. Por sua vez, o clima é dependente dos mecanismos oceânicos tropicais, a exemplo das fases de El Niño/La Niña sobre o Pacífico. O presente trabalho contribui com esta temática e reporta as correlações entre o índice MEI (Multivariate ENOS Index) do Pacífico e o número de casos notificados de dengue em sete capitais da Amazônia brasileira, no período de 2001 a 2012. Além disso, investiga-se o padrão de sazonalidade (médias trimestrais) dos casos de dengue ao longo da região. As evidências de que o fenômeno El Niño/La Niña provoca redução/aumento no padrão pluviométrico local é consistente com o número menor/maior de casos notificados de dengue na maior parte das capitais amazônicas, cujo resultado foi comprovado pelas correlações negativas estatisticamente significantes encontradas para Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) e Palmas (Tocantins). As médias dos 12 anos (2001/2012) revelaram a presença de sazonalidade pronunciada na incidência de dengue na maioria das capitais, com picos acentuados de janeiro a março [Rio Branco (Acre), Manaus, Belém e Palmas] e de abril a junho (São Luís), correspondendo em torno de 50% a 70% do total anual. As localidades mais ao norte [Boa Vista (Roraima) e Macapá (Amapá)] revelaram registro da dengue ao longo de todos os trimestres do ano, não apresentando sazonalidade acentuada.
Abstract: The dynamics of dengue transmission are multifactorial and involve socioeconomic, ecological, and environmental aspects, the latter being closely related to local climatic conditions that affect the vector's reproductive cycle. Climate depends in turn on tropical oceanic mechanisms such as phases of El Niño/La Niña over the Pacific. The study contributes to this discussion and reports on the correlations between the Multivariate ENSO Index (MEI) in the Pacific and the number of reported dengue cases in seven state capitals in the Brazilian Amazon from 2001 to 2012. The study also analyzes the seasonality pattern (quarterly mean values) in dengue cases throughout the region. Evidence that El Niño/La Niña causes a decrease versus increase in the local rainfall pattern is consistent with the lower versus higher number of reported dengue cases in most of the state capitals in the Amazon, a result proven by the statistically significant negative correlations seen in Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) and Palmas (Tocantins). The 12-years means (2001-2012) revealed the presence of pronounced seasonality in dengue incidence in the majority of the state capitals, with sharp peaks from January to March [Rio Branco (Acre), Manaus, Belém and Palmas] and from April to June (São Luís), corresponding to 50-70% of the annual total. State capitals farther north [Boa Vista (Roraima) and Macapá (Amapá)] showed dengue reporting in all quarters of the year, with no pronounced seasonality.
Resumen: La dinámica de transmisión del dengue es multifactorial e implica aspectos socioeconómicos, ecológicos y ambientales, estando estos últimos íntimamente relacionados con las condiciones climáticas locales que interfieren en el ciclo reproductivo de los vectores de la enfermedad. A su vez, el clima depende de los mecanismos oceánicos tropicales, como por ejemplo las fases de El Niño/La Niña sobre el Pacífico. El presente trabajo contribuye a esta temática e informa sobre las correlaciones entre el índice MEI (Multivariate ENOS Index) del Pacífico y el número de casos notificados de dengue en siete capitales de la Amazonia brasileña durante el período de 2001 a 2012. Además, se investiga el patrón de estacionalidad (medias trimestrales) de los casos de dengue a lo largo de la región. Las evidencias de que el fenómeno El Niño/La Niña provoca reducción/aumento en el patrón pluviométrico local es consistente con el número menor/mayor de casos notificados de dengue en la mayor parte de las capitales amazónicas, cuyo resultado se comprobó por las correlaciones negativas estadísticamente significativas encontradas en Manaus (Amazonas), São Luís (Maranhão), Belém (Pará) y Palmas (Tocantins). Las medias de los doce años (2001/2012) revelaron la presencia de estacionalidad pronunciada en la incidencia de dengue en la mayoría de las capitales, con picos acentuados de enero a marzo [Rio Branco (Acre), Manaus, Belém y Palmas] y de abril a junio (São Luís), correspondiendo en torno del 50 al 70% del total anual. Las localidades más al norte [Boa Vista (Roraima) y Macapá (Amapá)] revelaron registro del dengue a lo largo de todos los trimestres del año, no presentando una estacionalidad acentuada.
Asunto(s)
Humanos , Animales , Dengue/epidemiología , El Niño Oscilación del Sur/efectos adversos , Estaciones del Año , Brasil/epidemiología , Incidencia , Dengue/transmisión , Vectores de EnfermedadesRESUMEN
Abstract Copepods are an important planktonic group, and account for most of the total biomass and species diversity in pelagic marine ecosystems. Seasonal variability of the community structure of copepods in the Eastern tropical Pacific off central Mexico was studied during three distinct hydrodynamic periods in 2010 using statistical and multivariate analyses. The survey period included the second half of the 2009-2010 El Niño (January), the neutral transition period (May-June), and the first half of the 2010-2011 La Niña (October). Seventy-eight copepod species were identified; richness ranged from 11 to 47 species per station, with seasonal averages from 25 species in May to 35 species in January. Cluster analysis indicated that there were four principal groups present across the surveyed periods, defined by January (El Niño), October (La Niña), May offshore stations, and May upwelling stations (cyclonic eddy and coastal stations). There were no significant differences in abundance, but the January (El Niño) cluster was most diverse with 32 species, May offshore and October (La Niña) clusters each had 25 species, and the May upwelling was the least diverse cluster with 18 species. Mesoscale processes were strongest during May, which was the only period with a significant inshore-offshore gradient of species richness and diversity. Canonical correspondence analysis (CCA) revealed that variability was primarily driven by subsurface (75-200 m) ammonium, and surface (0-50 m) temperature, nitrates+nitrites, salinity and phosphorus. Copepodites and adults of the primarily herbivorous Eucalanidae dominated the stations of the upwelling cluster, while copepodites and adults of the carnivorous Euchaetidae dominated the January (El Niño) station cluster. The higher Chl a levels during the less productive (reduced upwelling) El Niño period were probably due to reduced grazing activities and increased ammonium availability through increased zooplankton metabolism. The horizontal distribution of copepods in the Eastern Tropical Pacific off Mexico appears to be principally defined by mesoscale eddy processes (offshore) and upwelling (coastal). These mesoscale processes were affected by El Niño - La Niña transitions, which subsequently disrupted the inshore-offshore gradient and in the case of El Niño likely caused reductions in copepod abundance across the entire region which persisted for the entire study period, and possibly longer.(AU)
Resumen Los copépodos son un importante grupo planctónico y representan la mayor parte de la biomasa total y la diversidad de especies en los ecosistemas marinos pelágicos. La variabilidad estacional de la estructura de la comunidad de copépodos se analizó en el Pacífico central mexicano durante tres períodos hidrodinámicos durante el 2010, mediante análisis estadísticos y multivariados. El período de estudio incluyó la segunda mitad del Niño 2009-2010 (enero), el período de transicional (mayo) y la primera mitad del La Niña 2010-2011 (octubre). Setenta y ocho especies de copépodos fueron identificadas; la riqueza varió de 11 a 47 especies por estación, con promedios estacionales de 25 especies en mayo a 35 especies en enero. El análisis de clúster indicó la presencia de cuatro grupos principales en los períodos estudiados: enero (El Niño), octubre (La Niña), un grupo de estaciones oceánicas en mayo, y un grupo de estaciones de afloramientos en mayo (remolino ciclónico y estaciones costeras). No hubo diferencias significativas en la abundancia entre grupos, pero el grupo de enero (El Niño) fue más diverso con 32 especies. Los grupos de mayo (oceánico) y octubre (La Niña) tenían 25 especies cada uno, y el grupo de mayo (afloramientos) fue el menos diverso con 18 especies. Los procesos de mesoescala fueron más intensos durante mayo, que fue el único período con un gradiente significativo costeroocéano de riqueza de especies y diversidad. El análisis de correspondencias canónicas explicó que la variabilidad se debe principalmente a la concentración de amonio en la capa profunda (75-200), y la temperatura, nitratos + nitritos, salinidad y fósforo presente en la capa superficial (0-50 m) de la columna de agua. Los copepoditos y adultos herbívoros de la familia Eucalanidae, dominaron las estaciones de surgencia, mientras que los copepoditos y adultos carnívoros de Euchaetidae dominaron las estaciones de enero (El Niño). Las concentraciones más altas de Clorofila a durante El Niño, que fue el periodo menos productivo (surgencia reducida), se deben probablemente a la reducción de actividades de pastoreo. La distribución horizontal de copépodos en el Pacífico central mexicano parece estar definida principalmente por la influencia de remolinos de mesoescala (mar adentro) y surgencias (costera). Estos procesos oceanográficos fueron afectados por la transición de El Niño a La Niña, que posteriormente interrumpieron el gradiente costero-oceánico y en el caso de El Niño probablemente causó una disminución en la abundancia de copépodos en toda la región durante todo el período de estudio, que posiblemente persistió en los meses posteriores.(AU)
Asunto(s)
Estaciones del Año , Zooplancton , Turbulencia del Fluido , Copépodos , El Niño Oscilación del Sur/efectos adversos , MéxicoRESUMEN
Climate change increases local climatic variation and unpredictability, which can alter ecological interactions and trigger wildlife disease outbreaks. Here we describe an unprecedented multi-species outbreak of wild fish disease driven by a climate perturbation. The 2015-16 El Niño generated a +2.5 °C sea surface temperature anomaly in the Galapagos Islands lasting six months. This coincided with a novel ulcerative skin disease affecting 18 teleost species from 13 different families. Disease signs included scale loss and hemorrhagic ulcerated patches of skin, fin deterioration, lethargy, and erratic behavior. A bacterial culture isolated from skin lesions of two of the affected fish species was identified by sequencing of the 16S rRNA gene as a Rahnella spp. Disease prevalence rates were linearly correlated with density in three fish species. In January 2016, disease prevalence reached 51.1% in the ring-tailed damselfish Stegastes beebei (n = 570) and 18.7% in the king angelfish Holacanthus passer (n = 318), corresponding to 78% and 86% decreases in their populations relative to a 4.5-year baseline, respectively. We hypothesize that this outbreak was precipitated by the persistent warm temperatures and lack of planktonic productivity that characterize extreme El Niño events, which are predicted to increase in frequency with global warming.
Asunto(s)
Brotes de Enfermedades/veterinaria , El Niño Oscilación del Sur/efectos adversos , Enfermedades de los Peces/epidemiología , Peces/fisiología , Enfermedades de la Piel/veterinaria , Úlcera/veterinaria , Animales , Cambio Climático , Ecosistema , Ecuador/epidemiología , Enfermedades de los Peces/etiología , Enfermedades de los Peces/patología , Calentamiento Global , Enfermedades de la Piel/etiología , Enfermedades de la Piel/patología , Úlcera/etiología , Úlcera/patologíaRESUMEN
A number of studies indicate that tropical arthropods should be particularly vulnerable to climate warming. If these predictions are realized, climate warming may have a more profound impact on the functioning and diversity of tropical forests than currently anticipated. Although arthropods comprise over two-thirds of terrestrial species, information on their abundance and extinction rates in tropical habitats is severely limited. Here we analyze data on arthropod and insectivore abundances taken between 1976 and 2012 at two midelevation habitats in Puerto Rico's Luquillo rainforest. During this time, mean maximum temperatures have risen by 2.0 °C. Using the same study area and methods employed by Lister in the 1970s, we discovered that the dry weight biomass of arthropods captured in sweep samples had declined 4 to 8 times, and 30 to 60 times in sticky traps. Analysis of long-term data on canopy arthropods and walking sticks taken as part of the Luquillo Long-Term Ecological Research program revealed sustained declines in abundance over two decades, as well as negative regressions of abundance on mean maximum temperatures. We also document parallel decreases in Luquillo's insectivorous lizards, frogs, and birds. While El Niño/Southern Oscillation influences the abundance of forest arthropods, climate warming is the major driver of reductions in arthropod abundance, indirectly precipitating a bottom-up trophic cascade and consequent collapse of the forest food web.
Asunto(s)
Artrópodos/crecimiento & desarrollo , Clima Tropical/efectos adversos , Animales , Biodiversidad , Biomasa , Aves/crecimiento & desarrollo , Ecosistema , El Niño Oscilación del Sur/efectos adversos , Cadena Alimentaria , Bosques , Puerto Rico , Bosque Lluvioso , Árboles/crecimiento & desarrolloRESUMEN
This paper investigates the persistent effects of negative shocks in utero and in infancy on low-income children's health and cognitive outcomes and examines whether timing of exposure matters differentially by skill type. Specifically, I exploit the geographic intensity of extreme floods in Ecuador during the 1997-1998 El Niño phenomenon, which provides exogenous variation in exposure at different periods of early development. I show that children exposed to severe floods in utero, especially during the third trimester, are shorter in stature five and seven years later. Also, children affected by the floods in the first trimester of pregnancy score lower on cognitive tests. Additionally, I explore potential mechanisms by studying health at birth and family inputs (income, consumption, and breastfeeding). I find that children exposed to El Niño floods, especially during the third trimester in utero, were more likely to be born with low birth weight. Furthermore, households affected by El Niño suffered a decline in income, total consumption, and food consumption in the aftermath of the shock. Falsification exercises and robustness checks suggest that selection concerns such as selective fertility, mobility, and infant mortality do not drive these results.
Asunto(s)
Salud Infantil/estadística & datos numéricos , Desastres/economía , El Niño Oscilación del Sur/efectos adversos , Inundaciones/economía , Factores Socioeconómicos , Adulto , Niño , Salud Infantil/economía , Preescolar , Ecuador/epidemiología , Femenino , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Pobreza/economía , Pobreza/estadística & datos numéricos , Embarazo , Resultado del Embarazo/economía , Resultado del Embarazo/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Rabies is a major zoonotic disease affecting humans, domestic and wildlife mammals. Cattle are the most important domestic animals impacted by rabies virus in the New World, leading to thousands of cattle deaths per year and eliciting large economic losses. In the New World, virus transmission in cattle is primarily associated with Desmodus rotundus, the common vampire bat. This study analyses the association of weather fluctuations and the El Niño Southern Oscillation (ENSO), with the occurrence and magnitude, in terms of associated mortality, of cattle rabies outbreaks. Data from the 100 cattle rabies outbreaks recorded between 1985 and 2016 in Costa Rica were analyzed. Periodograms for time series of rabies outbreaks and the El Niño 4 index were estimated. Seasonality was studied using a seasonal boxplot. The association between epidemiological and climatic time series was studied via cross wavelet coherence analysis. Retrospective space-time scan cluster analyses were also performed. Finally, seasonal autoregressive time series models were fitted to study linear associations between monthly number of outbreaks, monthly mortality rates and the El Niño 4 index, temperature, and rainfall. RESULTS: Large rabies mortality occurred towards the Atlantic basin of the country. Outbreak occurrence and size were not directly associated with ENSO, but were sensitive to weather variables impacted by ENSO. Both, ENSO phases and rabies outbreaks, showed a similar 5 year period in their oscillations. Cattle rabies mortality and outbreak occurrence increased with temperature, whereas outbreak occurrence decreased with rainfall. These results suggest that special weather conditions might favor the occurrence of cattle rabies outbreaks. CONCLUSIONS: Further efforts are necessary to articulate the mechanisms underpinning the association between weather changes and cattle rabies outbreaks. One hypothesis is that exacerbation of cattle rabies outbreaks might be mediated by impacts of weather conditions on common vampire bat movement and access to food resources on its natural habitats. Further eco-epidemiological field studies could help to understand rabies virus transmission ecology, and to propose sound interventions to control this major veterinary public health problem.