RESUMO
This study determined the influence of foraging distance, environmental factors, and native vegetation on honeybee (Apis mellifera) foraging in arid shrublands and grasslands in Northern Mexico. Apiary distance from inflorescence sites did not have a significant influence on the intensity of foraging. Apiary location and landscape were decisive factors in the response of honeybees to environmental factors. Air temperature, minimum temperature, wind velocity, and relative humidity explained foraging by 87, 80, 68, and 41% (R2), respectively, in shrubland sites in open landscapes but had no significant influence on foraging in the grassland sites in a valley surrounded by hills (1820-2020 amsl). Nights with a minimum temperature of <20 °C increased foraging activity during the day. Minimum temperature, which has the least correlative influence among climate elements, can be used to determine climate change's impact on bees. The quantity of available inflorescence explained the foraging intensity by 78% in shrublands and 84% in grasslands. Moreover, when honeybees depended mainly on native vegetation in grasslands, the quantity of inflorescence explained the intensity of foraging by 95%. High intensity of honeybee foraging was observed in allthorn (Koeberlinia spinosa) and wait-a-minute bush (Mimosa aculeaticarpa) in shrublands and honey mesquite (Neltuma glandulosa) and wait-a-minute bush (Mimosa aculeaticarpa) in grasslands. The findings and baseline data contributed by this study may be used to identify suitable environments for increasing apiary productivity and other agricultural and ecological benefits.
RESUMO
INTRODUCTION: The aim of the study was to investigate the relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments of the province of Catamarca, Argentina. METHODS: The departments Capital, Andalgalá, Paclín, Ambato and Tinogasta, Catamarca, Argentina, were studied. Between April 2021 and April 2022 variables analyzed were: number of COVID-19 cases, temperature, and percentage of environmental humidity. The correlation of variables was analyzed by the coefficient of Spearman. RESULTS: The temperature with the numbers of COVID-19 cases show inverse correlation values that ranged between -0.56 and -0.34. The humidity percentages show a slightly positive relationship only for Capital and Andalgalá, with values of 0.34 and 0.40 with the number of cases. CONCLUSION: The results showed a relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments in the province of Catamarca.
Introducción: El objetivo del trabajo fue estudiar la relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca. Métodos: Los departamentos estudiados fueron Capital, Andalgalá, Paclín, Ambato y Tinogasta, Catamarca, Argentina. Las variables número de casos COVID-19, temperatura y porcentaje de humedad ambiental fueron obtenidos entre abril de 2021 y abril de 2022. La correlación de variables se analizó mediante el coeficiente de Spearman. Resultados: La temperatura, en relación con los nú- meros de casos por COVID-19 mostró valores de correlación inversa que oscilaron entre -0.56 y -0.34. El porcentaje de humedad, indicó una relación levemente positiva con el número de casos solo para Capital y Andalgalá con valores de 0.34 y 0.40. Conclusión: Los resultados muestran una relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca.
Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Argentina/epidemiologiaRESUMO
Resumen Introducción : El objetivo del trabajo fue estudiar la relación entre el número de casos positivos de CO VID-19 y los parámetros ambientales de temperatura y humedad en cinco departamentos de la provincia de Catamarca. Métodos : Los departamentos estudiados fueron Ca pital, Andalgalá, Paclín, Ambato y Tinogasta, Catamarca, Argentina. Las variables número de casos COVID-19, temperatura y porcentaje de humedad ambiental fueron obtenidos entre abril de 2021 y abril de 2022. La corre lación de variables se analizó mediante el coeficiente de Spearman. Resultados : La temperatura, en relación con los nú meros de casos por COVID-19 mostró valores de co rrelación inversa que oscilaron entre -0.56 y -0.34. El porcentaje de humedad, indicó una relación levemente positiva con el número de casos solo para Capital y Andalgalá con valores de 0.34 y 0.40. Conclusión : Los resultados muestran una relación entre el número de casos positivos de COVID-19 y los parámetros ambientales de temperatura y hu medad en cinco departamentos de la provincia de Catamarca.
Abstract Introduction : The aim of the study was to investi gate the relationship between the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments of the province of Catamarca, Argentina. Methods : The departments Capital, Andalgalá, Paclín, Ambato and Tinogasta, Catamarca, Argentina, were stud ied. Between April 2021 and April 2022 variables analyzed were: number of COVID-19 cases, temperature, and per centage of environmental humidity. The correlation of variables was analyzed by the coefficient of Spearman. Results : The temperature with the numbers of CO VID-19 cases show inverse correlation values that ranged between -0.56 and -0.34. The humidity percentages show a slightly positive relationship only for Capital and Andal galá, with values of 0.34 and 0.40 with the number of cases. Conclusion : The results showed a relationship be tween the number of positive cases of COVID-19 and the environmental parameters of temperature and humidity in five departments in the province of Catamarca.
RESUMO
To investigate the influence of climate on hospitalizations of sickle cell anemia (SCA) adults and children, we analyzed the health and meteorological parameters from a metropolis (1999-2018). 1462 hospitalizations were coded for SCA patients in crisis (M:F = 715:747) and 1354 hospitalizations for SCA patients without crisis (M:F = 698:656) [age = 22.9 vs 15.2 years and duration of hospitalization (DoH) = 5.7 vs 4.4 days, respectively,]. More hospitalizations were for adults than children in crisis, and for children than adults without crisis. More children and adults were hospitalized in winter andspring than in summer and autumn Hospitalizations correlated positively with humidity (lag -5), maximum pressure (lag -2), mean pressure (lag -2), and thermal amplitude (lag -2), and negatively with maximum temperature (lag -3). DoH positively correlated with minimum temperature (lag -4). Understanding these complex associations would induce attitudinal/behavioral modifications among patients and their caregivers.
Assuntos
Anemia Falciforme , Clima , Criança , Adulto , Humanos , Adulto Jovem , Estudos Retrospectivos , Brasil/epidemiologia , Anemia Falciforme/epidemiologia , HospitalizaçãoRESUMO
Lakes in subtropical regions are highly susceptible to eutrophication due to the heavy rainfall, which causes significant runoff of pollutants (e.g., nutrients) to reach surface waters, altering the water quality and influencing the microbial communities that regulate the biogeochemical cycles within these ecosystems. Lake Cajititlán is a shallow, subtropical, and endorheic lake in western Mexico. Nutrient pollution from agricultural activity and wastewater discharge have affected the lake's water quality, leading the reservoir to a hypereutrophic state, resulting in episodes of fish mortality during the rainy season. This study investigated the temporal dynamics of bacterial communities within Lake Cajititlán and their genes associated with the nitrogen, phosphorus, sulfur, and carbon biogeochemical cycles during the rainy season, as well as the influences of physicochemical and environmental variables on such dynamics. Significant temporal variations were observed in the composition of bacterial communities, of which Flavobacterium and Pseudomonas were the dominant genera. The climatological parameters that were most correlated with the bacterial communities and their functional profiles were pH, DO, ORP, turbidity, TN, EC, NH4 +, and NO3 -. The bacterial communities displayed variations in their functional composition for nitrogen, phosphorus, and sulfur metabolisms during the sampling months. The bacterial communities within the lake are highly susceptible to nutrient loads and low DO levels during the rainy season. Bacterial communities had a higher relative abundance of genes associated with denitrification, nitrogen fixation, assimilatory sulfate reduction, cysteine, SOX system, and all phosphorus metabolic pathways. The results obtained here enrich our understanding of the bidirectional interactions between bacterial communities and major biogeochemical processes in eutrophic subtropical lakes.
RESUMO
Lake Cajititlán is a small, shallow, subtropical lake located in an endorheic basin in western Mexico. It is characterized by a strong seasonality of climate with pronounced wet and dry seasons and has been classified as a hypereutrophic lake. This eutrophication was driven by improperly treated sewage discharges from four municipal wastewater treatment plants (WWTPs) and by excessive agricultural activities, including the overuse of fertilizers that reach the lake through surface runoff during the rainy season. This nutrient rich runoff has caused algal blooms, which have led to anoxic or hypoxic conditions, resulting in large-scale fish deaths that have occurred during or immediately after the rainy season. This study investigated the changes in the phytoplankton community in Lake Cajititlán during the rainy season and the association between these changes and the physicochemical water quality and environmental parameters measured in the lake's basin. Planktothrix and Cylindrospermopsis were the dominant genera of the cyanobacterial community, while the Chlorophyceae, Chrysophyceae, and Trebouxiophyceae classes dominated the microalgae community. However, the results showed a significant temporal shift in the phytoplankton communities in Lake Cajititlán induced by the rainy season. The findings of this study suggest that significant climatic variations cause high seasonal surface runoff and rapid changes in the water quality (Chlorophyll-a, DO, NH4 +, and NO3 -) and in variations in the composition of the phytoplankton community. Finally, an alternation between phosphorus and nitrogen limitation was observed in Lake Cajititlán during the rainy season, clearly correlating to the presence of Planktothrix when the lake was limited by phosphorus and to the presence of Cylindrospermopsis when the lake was limited by nitrogen. The evidence presented in this study supports the idea that the death of fish in Lake Cajititlán could be mainly caused by anoxia, caused by rapid changes in water quality during the rainy season. Based on our review of the literature, this is the first study on the phytoplankton community in a subtropical lake during the rainy season using high throughput 16S rRNA and 18S rRNA amplicon sequencing.
RESUMO
Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.(AU)
As florestas ripárias apresentam fatores bióticos e abióticos que influenciam a dissimilaridade ambiental, e que refletem a distribuição específica de samambaias. O objetivo deste trabalho foi avaliar a heterogeneidade ambiental associada às comunidades de samambaias terrícolas em remanescentes de mata ciliar dos campos da metade sul do estado do Rio Grande do Sul (Pampa). Foram amostradas dez parcelas de 5×5 m em cada sítio (AI, AII e AIII), totalizando 30 parcelas. Em cada quadro, foram inventariadas as espécies de samambaia, além de outros parâmetros vegetacionais, microclimáticos e edáficos. Um total de 24 espécies foram identificadas nos três remanescentes de mata ciliar, distribuídas em 19 gêneros e 10 famílias. A Análise de Componentes Principais (PCA) mostrou que as parcelas de AI apresentaram os maiores valores de temperatura e alumínio, enquanto a umidade foi a menor, o que se refletiu na diminuição da riqueza de samambaias. A umidade do solo e a umidade do ar foram as variáveis mais relacionadas às parcelas de AII e AIII, indicando que essas plantas foram favorecidas nesses. A identidade florística característica de cada local sugere que muitas espécies são dependentes de certas condições ambientais locais. Nesse sentido, mesmo em sítios geograficamente próximos, remanescentes de matas ciliares merecem atenção no que se refere a conservação, uma vez que são capazes de abrigar grande diversidade nesta fitofisionomia exclusiva do sul do Brasil. Os resultados deste estudo integrado, com parâmetros vegetacionais, climáticos e edáficos, sugerem, que as samambaias respondem categoricamente à heterogeneidade mostrada pelos ambientes ripários, mesmo quando os fragmentos estão próximos.(AU)
Assuntos
Gleiquênias , Biodiversidade , BrasilRESUMO
Abstract Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.
Resumo As florestas ripárias apresentam fatores bióticos e abióticos que influenciam a dissimilaridade ambiental, e que refletem a distribuição específica de samambaias. O objetivo deste trabalho foi avaliar a heterogeneidade ambiental associada às comunidades de samambaias terrícolas em remanescentes de mata ciliar dos campos da metade sul do estado do Rio Grande do Sul (Pampa). Foram amostradas dez parcelas de 5×5 m em cada sítio (AI, AII e AIII), totalizando 30 parcelas. Em cada quadro, foram inventariadas as espécies de samambaia, além de outros parâmetros vegetacionais, microclimáticos e edáficos. Um total de 24 espécies foram identificadas nos três remanescentes de mata ciliar, distribuídas em 19 gêneros e 10 famílias. A Análise de Componentes Principais (PCA) mostrou que as parcelas de AI apresentaram os maiores valores de temperatura e alumínio, enquanto a umidade foi a menor, o que se refletiu na diminuição da riqueza de samambaias. A umidade do solo e a umidade do ar foram as variáveis mais relacionadas às parcelas de AII e AIII, indicando que essas plantas foram favorecidas nesses. A identidade florística característica de cada local sugere que muitas espécies são dependentes de certas condições ambientais locais. Nesse sentido, mesmo em sítios geograficamente próximos, remanescentes de matas ciliares merecem atenção no que se refere a conservação, uma vez que são capazes de abrigar grande diversidade nesta fitofisionomia exclusiva do sul do Brasil. Os resultados deste estudo integrado, com parâmetros vegetacionais, climáticos e edáficos, sugerem, que as samambaias respondem categoricamente à heterogeneidade mostrada pelos ambientes ripários, mesmo quando os fragmentos estão próximos.
Assuntos
Humanos , Gleiquênias , Solo , Brasil , Florestas , BiodiversidadeRESUMO
In order to run a series of in vitro studies on the effect of extremely low-frequency magnetic fields on cell cultures, developing and characterizing an appropriate exposure system is required. The present design is based on a two-shielded Lee-Whiting coils system. The circular design was chosen because its axial symmetry allowed for both reducing simulation unknowns and measurement points during the characterization, and additionally made the machining of the parts easier. The system can generate magnetic flux densities (B fields) up to 1 mT root-mean-square amplitude (rms) with no active cooling system in the incubator, and up to 3 mTrms with it. The double-wrapped windings with twisted pairs allow for the use of each set of coils either as exposure or control with no detectable parasitic B field in the control. The artifacts have also been analyzed; the B field in the center of the sham control chamber is about 1 µTrms for a maximum of 3 mTrms in the exposure chamber, the parasitic incident electric fields are less than 1 V/m, the temperature difference between sham and exposure chamber is less than or equal to 0.2 °C, and the typical vibration difference between sham and exposure is less than 0.1 m/s2 . © 2020 Bioelectromagnetics Society.
Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição à Radiação/análise , Radiometria/instrumentação , Desenho de EquipamentoRESUMO
Water is the most important nutrient in animal nutrition; however, water intake is rarely measured. The objective of this study was to determine whether previously published water intake (WI) equations for beef cattle would accurately predict WI from four experiments conducted under tropical conditions. The experiments were conducted from 2013 to 2015. Nellore (Bos indicus) growing bulls (Exps. 1, 2, and 3) and heifers (Exp. 4) were used in the feedlot trials. In all experiments, animals were fed for ad libitum DMI. The WI, animal performance, diet composition, and environmental data were collected. The prediction of WI using the current published WI equations was evaluated by regressing predicted and measured WI values. The regression was evaluated using the two-hypothesis test: H0: ß0 = 0 and H0: ß1 = 1 and Ha: not H0. If both null hypotheses were not rejected, it was concluded that the tested equation accurately estimated WI. To develop a WI prediction equation based on the input variables, a leave-one-out cross-validation method was proposed. The proposed equation was evaluated using similar methodology described above. All previously published eight equations overestimated WI of cattle used in the four experiments conducted in southeast Brazil. A possible explanation for the overestimate of WI is that previously published WI equations were generated from data collected from predominantly Bos taurus cattle raised under temperate climates. From the data collected from experiments conducted with Nellore cattle in southeast Brazil, the proposed equation (WI = 9.449 + 0.190 × MBW + 0.271 × TMAX -0.259 × HU + 0.489 × DMI, where the MBW is the metabolic BW (kg0.75), TMAX is the maximum temperature (°C), HU is the humidity (%) and DMI in kg/d), more accurately to predicts WI of cattle raised under tropical conditions.
Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Ingestão de Líquidos , Animais , Brasil , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Feminino , Umidade , Masculino , Clima TropicalRESUMO
Abstract Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.
Resumo As florestas ripárias apresentam fatores bióticos e abióticos que influenciam a dissimilaridade ambiental, e que refletem a distribuição específica de samambaias. O objetivo deste trabalho foi avaliar a heterogeneidade ambiental associada às comunidades de samambaias terrícolas em remanescentes de mata ciliar dos campos da metade sul do estado do Rio Grande do Sul (Pampa). Foram amostradas dez parcelas de 5×5 m em cada sítio (AI, AII e AIII), totalizando 30 parcelas. Em cada quadro, foram inventariadas as espécies de samambaia, além de outros parâmetros vegetacionais, microclimáticos e edáficos. Um total de 24 espécies foram identificadas nos três remanescentes de mata ciliar, distribuídas em 19 gêneros e 10 famílias. A Análise de Componentes Principais (PCA) mostrou que as parcelas de AI apresentaram os maiores valores de temperatura e alumínio, enquanto a umidade foi a menor, o que se refletiu na diminuição da riqueza de samambaias. A umidade do solo e a umidade do ar foram as variáveis mais relacionadas às parcelas de AII e AIII, indicando que essas plantas foram favorecidas nesses. A identidade florística característica de cada local sugere que muitas espécies são dependentes de certas condições ambientais locais. Nesse sentido, mesmo em sítios geograficamente próximos, remanescentes de matas ciliares merecem atenção no que se refere a conservação, uma vez que são capazes de abrigar grande diversidade nesta fitofisionomia exclusiva do sul do Brasil. Os resultados deste estudo integrado, com parâmetros vegetacionais, climáticos e edáficos, sugerem, que as samambaias respondem categoricamente à heterogeneidade mostrada pelos ambientes ripários, mesmo quando os fragmentos estão próximos.
RESUMO
Abstract Araçá Bay, located in the city of São Sebastião, São Paulo, Brazil, is a protected area of substantial complexity. It represents the last remaining mangrove swamp preserve between the cities of Bertioga and Ubatuba on the northern coast of São Paulo State. This mangrove swamp has specific physical and chemical properties, and it shelters a wide variety of life, including fungi. These microorganisms are present in a variety of species with different morphophysiological features, and they have the ability to produce enzymes of biotechnological importance. The goal of this study was to quantify, isolate, and identify filamentous fungi in water and sediment samples from the Araçá Bay mangrove swamp in São Sebastião. Two samplings were performed in the summer and two were performed in the winter. The samples were collected from intertidal zones, and dissolved oxygen (DO), temperature, salinity, and pH were measured in situ. The spread plate technique was used to inoculate the samples collected on plates with a potato dextrose agar (PDA) medium. A total of 208 colonies (68 from water samples and 140 from sediment samples) were isolated, and they were identified based on their morphological characteristics. Filamentous fungus density was higher in the sediment than in the water, and the samplings performed in the winter revealed a higher density than those performed in the summer. Though some of the environmental parameters were not ideal for fungal development, a high quantity of growth was nevertheless observed. When the isolated colonies were analyzed, the greatest diversity and species richness were found in the summer samples. The genera identified in all of the samples were Aspergillus, Penicillium, Cladosporium, and Fusarium. The pathogenic species found from these genera were Aspergillus fumigatus, A. terreus, Penicillium citrinum, and P. chrysogenum. These species are also able to produce enzymes that offer a variety of applications. The fungal community described herein represents the diversity found in this mangrove swamp during the period studied. Many of the fungus species found are pathogenic and may be useful due to their ability to produce specific enzymes applicable in the biotechnological and pharmaceutical industries.
Resumo A Baía do Araçá, localizada no município de São Sebastião (SP), é uma região protegida, de grande complexidade, mantendo o último remanescente preservado de manguezal entre Bertioga e Ubatuba, litoral Norte do Estado de São Paulo. Manguezal caracteriza-se com propriedades físico-químicas específicas e abriga grande diversidade de seres vivos, entre eles os fungos. Estes microrganismos apresentam grande variedade de espécies e diferentes características morfofisiológicas com capacidade de produzir algumas enzimas de importância biotecnológica. Este trabalho teve como objetivo quantificar, isolar e identificar fungos filamentosos em amostras de água e de sedimento do manguezal da Baía do Araçá, São Sebastião, (SP). Foram realizadas 2 coletas no verão e 2 no inverno na região entremarés, medidos "in situ" os parâmetros oxigênio dissolvido (OD), temperatura, salinidade e pH. Utilizou-se a Técnica "Spread Plate" para inocular os materiais coletados, em placas com meio Potato Dextrose Agar (PDA). Foram isoladas 208 colônias (68 das amostras de água e 140 das amostras de sedimento) e identificadas pelas características morfofisiológicas. As densidades de fungos filamentosos foram maiores no sedimento em relação à água e nas coletas realizadas no inverno demonstraram maiores densidades do que no verão. Apesar de alguns parâmetros ambientais não se apresentarem ideais para o desenvolvimento dos fungos, observou-se alta quantidade de crescimento nas amostragens. Analisando as colônias isoladas, a maior diversidade e riqueza foram observadas na amostragem coletado no verão. Foram observados os gêneros Aspergillus sp, Penicillium sp, Cladosporium sp e Fusarium sp em todas as amostragens, dos quais as espécies Aspergillus fumigatus, A. terreus, Penicillium citrinum e P. chrysogenum identificados neste trabalho são considerados patogênicos mas também são espécies capazes de produzir enzimas aplicáveis em diversas atividades. A comunidade fúngica descrita apresenta a diversidade encontrada neste manguezal em relação à variedade ambiental no período estudado, sendo que muitos apresentam patogenicidade e podem ser uteis pela sua capacidade de produzir enzimas específicas aplicáveis nos estudos biotecnológicos e farmacêuticos.
RESUMO
Abstract Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.
Resumo As florestas ripárias apresentam fatores bióticos e abióticos que influenciam a dissimilaridade ambiental, e que refletem a distribuição específica de samambaias. O objetivo deste trabalho foi avaliar a heterogeneidade ambiental associada às comunidades de samambaias terrícolas em remanescentes de mata ciliar dos campos da metade sul do estado do Rio Grande do Sul (Pampa). Foram amostradas dez parcelas de 5×5 m em cada sítio (AI, AII e AIII), totalizando 30 parcelas. Em cada quadro, foram inventariadas as espécies de samambaia, além de outros parâmetros vegetacionais, microclimáticos e edáficos. Um total de 24 espécies foram identificadas nos três remanescentes de mata ciliar, distribuídas em 19 gêneros e 10 famílias. A Análise de Componentes Principais (PCA) mostrou que as parcelas de AI apresentaram os maiores valores de temperatura e alumínio, enquanto a umidade foi a menor, o que se refletiu na diminuição da riqueza de samambaias. A umidade do solo e a umidade do ar foram as variáveis mais relacionadas às parcelas de AII e AIII, indicando que essas plantas foram favorecidas nesses. A identidade florística característica de cada local sugere que muitas espécies são dependentes de certas condições ambientais locais. Nesse sentido, mesmo em sítios geograficamente próximos, remanescentes de matas ciliares merecem atenção no que se refere a conservação, uma vez que são capazes de abrigar grande diversidade nesta fitofisionomia exclusiva do sul do Brasil. Os resultados deste estudo integrado, com parâmetros vegetacionais, climáticos e edáficos, sugerem, que as samambaias respondem categoricamente à heterogeneidade mostrada pelos ambientes ripários, mesmo quando os fragmentos estão próximos.
RESUMO
Seasonal sampling was carried out at three Argentinian salterns, Salitral Negro (SN), Colorada Grande (CG) and Guatraché (G), to analyze abiotic parameters and microbial diversity and dynamics. Microbial assemblages were correlated to environmental factors by statistical analyses. Principal component analysis of the environmental data grouped SN and CG samples separately from G samples owing to G's higher pH values and sulfate concentration. Differences in microbial assemblages were also found. Many archaeal sequences belonged to uncultured members of Haloquadratum and Haloquadratum-related genera, with different environmental optima. Notably, nearly half of the archaeal sequences were affiliated to the recently described 'Candidatus Haloredividus' (phylum Nanohaloarchaeota), not previously detected in salt-saturated environments. Most bacterial sequences belonged to Salinibacter representatives, while sequences affiliated to the recently described genus Spiribacter were also found. Seasonal analysis showed at least 40% of the microbiota from the three salterns was prevalent through the year, indicating they are well adapted to environmental fluctuations. On the other hand, a minority of archaeal and bacterial sequences were found to be seasonally distributed. Five viral morphotypes and also eukaryal predators were detected, suggesting different mechanisms for controlling prokaryotic numbers. Notably, Guatraché was the saltern that harbored the highest virus-to-cell ratios reported to date for hypersaline environments.
Assuntos
Archaea/classificação , Bacteroidetes/classificação , Halobacteriales/classificação , Proteobactérias/classificação , Vírus/classificação , Archaea/genética , Archaea/isolamento & purificação , Argentina , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Halobacteriales/genética , Microbiota/genética , Microscopia Eletrônica de Transmissão , Análise de Componente Principal , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Estações do Ano , Água do Mar/microbiologia , Cloreto de Sódio , Vírus/genética , Vírus/isolamento & purificaçãoRESUMO
Alternaria arborescens has been reported as a common fungal species invading tomatoes and is capable of producing several mycotoxins in infected plants, fruits and in agricultural commodities. Alternariol (AOH), alternariol monomethyl ether (AME), and tenuazonic acid (TeA) are some of the main Alternaria mycotoxins that can be found as contaminants of food. This species can produce these toxic metabolites together with AAL toxins (Alternaria alternata f. sp. lycopersicum toxins), which can act as inhibitors of sphingolipid biosynthesis. The objective of this study was to determine the effect of water activity (aw, 0.995, 0.975, 0.950) and temperature (6, 15, 20, 25 and 30 °C) on mycotoxin production by A. arborescens on a synthetic tomato medium. The optimum production of AOH and AME occurred at 0.975 aw after 40 days of incubation at 30 °C. The maximum TeA accumulation was observed at 0.975 aw and 25 °C and at 0.950 aw and 30 °C. AAL TA was produced in higher quantities at 0.995 aw and 30 °C. At 6 °C no quantifiable levels of AOH or AME were detected, but significant amounts of TeA were produced at 0.975 aw. In general, high aw levels and high temperatures were favorable for mycotoxin production. The greatest accumulation of all four toxins occurred at 0.975 aw and 30 °C. The results obtained here could be extrapolated to evaluate the risk of tomato fruits and tomato products contamination caused by these toxins.
Assuntos
Alternaria/metabolismo , Micotoxinas/metabolismo , Solanum lycopersicum/microbiologia , Temperatura , Água/metabolismo , Alternaria/patogenicidade , Contaminação de Alimentos , Microbiologia de Alimentos , Frutas/química , Lactonas/metabolismo , Micotoxinas/análise , Esfingolipídeos/biossíntese , Ácido Tenuazônico/metabolismoRESUMO
Habitat use is different along the ontogenetic development of some species and may be influenced by environmental parameters. This study described the interaction of Atherinella brasiliensis caught in intertidal areas of the Paranaguá Estuarine Complex with environmental parameters. We caught 10024 individuals between August 2010 and July 2011, with total mean length of 44.32 mm (SD ± 25.37 mm), variation range between 12 and 142 mm, and weight between 0.01 and 73 g, averaging 1.35 g (SD ± 2.66 g) and ages estimated between 1 and 22 months. Significant differences were detected between sectors and periods for number of individuals and weight at capture, with higher mean values in the mean sector during the rainy period. The spatial and temporal distribution of ages was statistically different, individuals between 1 and 3 months were more abundant in the sector 2 during the rainy period, and individuals older than 7 months were evenly distributed throughout the sampling area, and with higher mean abundance at the beginning and end of the dry period. Environmental variables that most influenced the distribution of age classes were temperature and salinity.
O uso do habitat é diferenciado ao longo do desenvolvimento ontogenético em algumas espécies, podendo ser influenciado pelos parâmetros ambientais. O presente estudo descreve a interação da Atherinella brasiliensis capturada nas regiões intertidais do Complexo Estuarino de Paranaguá (CEP) com os parâmetros ambientais deste ambiente. Foram capturados 10024 indivíduos entre agosto de 2010 e julho de 2011, com comprimento total médio de 44,32 mm (DP = ± 25,37 mm), amplitude de variação entre 12 e 142 mm, e pesos entre 0,01 e 73 g, com média de 1,35g (DP = ± 2,66 g) e idades estimadas entre < 1 e 22 meses. Foram evidenciadas diferenças significativas entre setores e estações do ano no número de indivíduos e peso da captura, com maiores médias no setor mediano e na estação chuvosa. Diferenças estatísticas foram observadas na distribuição espaço-temporal das idades, com os indivíduos entre < 1 e 3 meses em média mais abundantes no setor 2 e período chuvoso, e os com indivíduos com idades acima de 7 meses igualmente distribuídos em toda a área amostral e com maior abundância média no início e final da seca. As variáveis ambientais que mais influenciaram na distribuição das classes etárias foram a temperatura e a salinidade.
Assuntos
Animais , Ecossistema/análise , Ecossistema/métodos , Peixes/classificação , Peixes/crescimento & desenvolvimentoRESUMO
Habitat use is different along the ontogenetic development of some species and may be influenced by environmental parameters. This study described the interaction of Atherinella brasiliensis caught in intertidal areas of the Paranaguá Estuarine Complex with environmental parameters. We caught 10024 individuals between August 2010 and July 2011, with total mean length of 44.32 mm (SD ± 25.37 mm), variation range between 12 and 142 mm, and weight between 0.01 and 73 g, averaging 1.35 g (SD ± 2.66 g) and ages estimated between < 1 and 22 months. Significant differences were detected between sectors and periods for number of individuals and weight at capture, with higher mean values in the mean sector during the rainy period. The spatial and temporal distribution of ages was statistically different, individuals between < 1 and 3 months were more abundant in the sector 2 during the rainy period, and individuals older than 7 months were evenly distributed throughout the sampling area, and with higher mean abundance at the beginning and end of the dry period. Environmental variables that most influenced the distribution of age classes were temperature and salinity.
O uso do habitat é diferenciado ao longo do desenvolvimento ontogenético em algumas espécies, podendo ser influenciado pelos parâmetros ambientais. O presente estudo descreve a interação da Atherinella brasiliensis capturada nas regiões intertidais do Complexo Estuarino de Paranaguá (CEP) com os parâmetros ambientais deste ambiente. Foram capturados 10024 indivíduos entre agosto de 2010 e julho de 2011, com comprimento total médio de 44,32 mm (DP = ± 25,37 mm), amplitude de variação entre 12 e 142 mm, e pesos entre 0,01 e 73 g, com média de 1,35g (DP = ± 2,66 g) e idades estimadas entre < 1 e 22 meses. Foram evidenciadas diferenças significativas entre setores e estações do ano no número de indivíduos e peso da captura, com maiores médias no setor mediano e na estação chuvosa. Diferenças estatísticas foram observadas na distribuição espaço-temporal das idades, com os indivíduos entre < 1 e 3 meses em média mais abundantes no setor 2 e período chuvoso, e os com indivíduos com idades acima de 7 meses igualmente distribuídos em toda a área amostral e com maior abundância média no início e final da seca. As variáveis ambientais que mais influenciaram na distribuição das classes etárias foram a temperatura e a salinidade.
Assuntos
Monitorização de Parâmetros Ecológicos , Ecossistema , PeixesRESUMO
The influence of environmental parameters on the total and pathogenic Vibrio parahaemolyticus seasonal densities in American oysters (Crassostrea virginica) was evaluated for 1 year. Harvesting site A yielded the highest mean densities of V. parahaemolyticus tlh+, tdh+/trh-, tdh-/trh+ and tdh+/trh+ during spring season at 2.57, 1.74, 0.36, and -0.40 log10 MPN/g, respectively, and tdh+/orf8+ during winter season (0.90 log10 MPN/g). V. parahaemolyticus tlh+ densities were associated to salinity (R(2)=0.372, P<0.022), tdh+/trh+ to turbidity (R(2)=0.597, P<0.035), and orf8+ to temperature, salinity, and pH (R(2)=0.964, P<0.001). The exposure to salinity and temperature conditions during winter and spring seasons regulated the dynamics of V. parahaemolyticus harboring potentially pathogenic genotypes within the oyster. The adaptive response of V. parahaemolyticus to seasonal environmental changes may lead to an increase in survival and virulence, threatening the seafood safety and increasing the risk of illness.
Assuntos
Crassostrea/microbiologia , Ostreidae/microbiologia , Água do Mar/química , Frutos do Mar/microbiologia , Vibrio parahaemolyticus/isolamento & purificação , Animais , Crassostrea/crescimento & desenvolvimento , Monitoramento Ambiental , México , Ostreidae/crescimento & desenvolvimento , Análise de Componente Principal , Salinidade , Estações do Ano , Temperatura , Vibrio parahaemolyticus/crescimento & desenvolvimento , Vibrio parahaemolyticus/patogenicidade , VirulênciaRESUMO
Habitat use is different along the ontogenetic development of some species and may be influenced by environmental parameters. This study described the interaction of Atherinella brasiliensis caught in intertidal areas of the Paranaguá Estuarine Complex with environmental parameters. We caught 10024 individuals between August 2010 and July 2011, with total mean length of 44.32 mm (SD ± 25.37 mm), variation range between 12 and 142 mm, and weight between 0.01 and 73 g, averaging 1.35 g (SD ± 2.66 g) and ages estimated between 1 and 22 months. Significant differences were detected between sectors and periods for number of individuals and weight at capture, with higher mean values in the mean sector during the rainy period. The spatial and temporal distribution of ages was statistically different, individuals between 1 and 3 months were more abundant in the sector 2 during the rainy period, and individuals older than 7 months were evenly distributed throughout the sampling area, and with higher mean abundance at the beginning and end of the dry period. Environmental variables that most influenced the distribution of age classes were temperature and salinity.(AU)
O uso do habitat é diferenciado ao longo do desenvolvimento ontogenético em algumas espécies, podendo ser influenciado pelos parâmetros ambientais. O presente estudo descreve a interação da Atherinella brasiliensis capturada nas regiões intertidais do Complexo Estuarino de Paranaguá (CEP) com os parâmetros ambientais deste ambiente. Foram capturados 10024 indivíduos entre agosto de 2010 e julho de 2011, com comprimento total médio de 44,32 mm (DP = ± 25,37 mm), amplitude de variação entre 12 e 142 mm, e pesos entre 0,01 e 73 g, com média de 1,35g (DP = ± 2,66 g) e idades estimadas entre < 1 e 22 meses. Foram evidenciadas diferenças significativas entre setores e estações do ano no número de indivíduos e peso da captura, com maiores médias no setor mediano e na estação chuvosa. Diferenças estatísticas foram observadas na distribuição espaço-temporal das idades, com os indivíduos entre < 1 e 3 meses em média mais abundantes no setor 2 e período chuvoso, e os com indivíduos com idades acima de 7 meses igualmente distribuídos em toda a área amostral e com maior abundância média no início e final da seca. As variáveis ambientais que mais influenciaram na distribuição das classes etárias foram a temperatura e a salinidade.(AU)
Assuntos
Animais , Peixes/classificação , Peixes/crescimento & desenvolvimento , Ecossistema/análise , Ecossistema/métodosRESUMO
The brachyuran crabs are iteroparous species which present a high diversification of reproduction patterns, which may have evolved as a species-specific response to environmental conditions. Tropical species commonly present a year-round reproduction due to stable environment conditions. Goniopsis cruentata is a crab species widely distributed along the Western Atlantic, inhabiting practically every microhabitat in the mangrove ecosystem. The aim of the present study is to determine the breeding period of the crab Goniopsis cruentata in Northeastern Brazil and also to evaluate the influence of water salinity, rainfall and air and water temperature on it. A total of 71 ovigerous females, captured from August-2007 to July-2008, were used to assess the breeding period of this species. It was analyzed by the monthly proportion of ovigerous females. A correlation was applied to verify the influence of the abiotic factors on the breeding period. The present population bred seasonal-continuously with peaks in the dry period, which was not associated with monthly variations of salinity, rainfall and air and water temperatures. Therefore, according to statistical analyses, our hypothesis was refuted. However, breeding was intensified in the dry period, when salinity and temperatures were higher and rainfall was lower. We conclude that, even though breeding is not related to monthly variation of environmental factors, it occurs in periods of higher salinity and temperatures and lower rainfall.
Los cangrejos Brachyura son especies iteróparas, que presentan alta diversificación en los patrones de reproducción, que pueden haber evolucionado como una respuesta específica de la especie a las condiciones ambientales. Las especies tropicales frecuentemente presentan una reproducción en todo el año debido a las condiciones estables del medio. El cangrejo Goniopsis cruentata es una especie ampliamente distribuida en largo del Atlántico occidental, y que habita prácticamente cada micro-hábitat en el ecosistema de manglar. El objetivo del presente estudio fue evaluar el periodo de reproducción del cangrejo G. cruentata en el noreste de Brasil. Un total de 71 hembras ovadas, fueron capturadas entre agosto 2007 y julio 2008, y utilizadas para obtener el periodo de reproducción de esta especie. Nuestra hipótesis es que, ya que las zonas tropicales no presentan gran variación de las temperaturas, las oscilaciones temporales de la salinidad son el principal factor que influye en la actividad reproductiva de G. cruentata. Se analizó el período reproductivo mediante la proporción mensual de hembras ovadas. Una correlación fue aplicada para evaluar la influencia de los factores abióticos limitantes (salinidad, pluviosidad, temperatura del aire y del agua) en la época de crianza. La población se reproduce continuamente con picos estacionales en el período seco, lo que no fue asociado a las variaciones mensuales de salinidad, precipitación y temperatura del aire y del agua. Por lo tanto, nuestra hipótesis fue refutada. Sin embargo, la reproducción se intensificó en el período seco, cuando la salinidad y las temperaturas fueron más altas y la precipitación fue menor. Se concluye que, a pesar de que la reproducción no está relacionada con la variación mensual de los factores ambientales limitantes, ella ocurre en períodos de mayor salinidad y temperatura, y baja precipitación.