RESUMO

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.

Assuntos

RESUMO

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.

RESUMO

Photodynamic therapy, by reducing pain and inflammation and promoting the proliferation of healthy cells, can be used to treat recurrent lesions, such as diabetic foot ulcers. Studies using the photosensitizer phthalocyanine, together with the nanostructured copolymeric matrix of Pluronic® and Carbopol® for the treatment of diabetic foot ulcers and leishmaniosis lesions, are showing promising outcomes. Despite their topical or subcutaneous administration, these molecules are absorbed and their systemic effects are unknown. Therefore, we investigated the effect of the subcutaneous administration of the hydroxy-aluminum phthalocyanine hydrogel without illumination on systemic parameters, markers of liver injury, and liver energy metabolism in type 1 diabetic Swiss mice. Both the hydrogel and the different doses of phthalocyanine changed the levels of injury markers and the liver glucose release, sometimes aggravating the alterations caused by the diabetic condition itself. However, the dose of 2.23 µg/mL caused less marked plasmatic and metabolic changes and did not change glucose tolerance or insulin sensitivity of the diabetic mice. These results are indicative that the use of hydroxy-aluminum phthalocyanine hydrogel for the treatment of cutaneous ulcers in diabetic patients is systemically safe.

Assuntos

RESUMO

Photodynamic therapy, by reducing pain and inflammation and promoting the proliferation of healthy cells, can be used to treat recurrent lesions, such as diabetic foot ulcers. Studies using the photosensitizer phthalocyanine, together with the nanostructured copolymeric matrix of Pluronic® and Carbopol® for the treatment of diabetic foot ulcers and leishmaniosis lesions, are showing promising outcomes. Despite their topical or subcutaneous administration, these molecules are absorbed and their systemic effects are unknown. Therefore, we investigated the effect of the subcutaneous administration of the hydroxy-aluminum phthalocyanine hydrogel without illumination on systemic parameters, markers of liver injury, and liver energy metabolism in type 1 diabetic Swiss mice. Both the hydrogel and the different doses of phthalocyanine changed the levels of injury markers and the liver glucose release, sometimes aggravating the alterations caused by the diabetic condition itself. However, the dose of 2.23 µg/mL caused less marked plasmatic and metabolic changes and did not change glucose tolerance or insulin sensitivity of the diabetic mice. These results are indicative that the use of hydroxy-aluminum phthalocyanine hydrogel for the treatment of cutaneous ulcers in diabetic patients is systemically safe.

Assuntos

RESUMO

Abstract Cladocerans are able to produce resting eggs inside a protective resistant capsule, the ephippium, that difficults the visualization of the resting eggs, because of the dark pigmentation. Therefore, before hatching experiments, methods to verify viable resting eggs in ephippia must be considered. This study aimed to evaluate the number of eggs per ephippium of Daphnia from two tropical aquatic ecosystems and the efficiency of some methods for decapsulating resting eggs. To evaluate the influence of methods on hatching rates, three different conditions were tested: immersion in sodium hypochlorite, manually decapsulated resting eggs and intact ephippia. The immersion in hypochlorite solution could evaluate differences in numbers of resting eggs per ephippium between the ecosystems studied. The exposure to sodium hypochlorite at a concentration of 2% for 20 minutes was the most efficient method for visual evaluation and isolation of the resting eggs. Hatching rate experiments with resting eggs not isolated from ephippia were underestimated (11.1 ± 5.0%), showing the need of methods to quantify and isolate viable eggs. There were no differences between the hatching rate of resting eggs submitted to hypochlorite solution (47.2 ± 7.34%) and manually decapsulated (53.7 ± 13.24%). However, the immersion in hypochlorite was a more efficient technique, faster and not requiring manual ability.

Resumo Cladóceros são capazes de produzir ovos de resistência envoltos por uma cápsula protetora, o efípio, que dificulta a visualização do número de ovos, devido à pigmentação escura. Assim, antes da condução de experimentos de eclosão, métodos para determinar o número de ovos de resistência viáveis no interior do efípio devem ser utilizados. Este estudo teve como objetivo avaliar o número de ovos por efípio de Daphnia de dois ecossistemas aquáticos tropicais e a eficiência de alguns métodos de desencapsulamento de ovos de resistência. Para avaliar a influência dos métodos na taxa de eclosão foram testadas três condições: imersão em hipoclorito de sódio, ovos de resistência desencapsulados manualmente e efípios intactos. A imersão em solução de hipoclorito permitiu avaliar as diferenças no número de ovos de resistência por efípios entre os ecossistemas. A exposição ao hipoclorito de sódio a uma concentração de 2% durante 20 minutos foi o método mais eficiente para a avaliação visual e isolamento dos ovos de resistência. A taxa de eclosão de ovos não isolados de efípios foi subestimada (11,1 ± 5,0%), mostrando a necessidade de métodos para quantificação e isolamento dos ovos. Não foi verificada diferença de eclosão entre os ovos isolados a partir da imersão em solução de hipoclorito (47,2 ± 7,34%) e manualmente desencapsulados (53,7 ± 13,24%). Entretanto, a imersão em hipoclorito é uma técnica mais eficiente, pois além de mais rápida, não necessita de destreza manual.

Assuntos

RESUMO

Cladocerans are able to produce resting eggs inside a protective resistant capsule, the ephippium, that difficults the visualization of the resting eggs, because of the dark pigmentation. Therefore, before hatching experiments, methods to verify viable resting eggs in ephippia must be considered. This study aimed to evaluate the number of eggs per ephippium of Daphnia from two tropical aquatic ecosystems and the efficiency of some methods for decapsulating resting eggs. To evaluate the influence of methods on hatching rates, three different conditions were tested: immersion in sodium hypochlorite, manually decapsulated resting eggs and intact ephippia. The immersion in hypochlorite solution could evaluate differences in numbers of resting eggs per ephippium between the ecosystems studied. The exposure to sodium hypochlorite at a concentration of 2% for 20 minutes was the most efficient method for visual evaluation and isolation of the resting eggs. Hatching rate experiments with resting eggs not isolated from ephippia were underestimated (11.1 ± 5.0%), showing the need of methods to quantify and isolate viable eggs. There were no differences between the hatching rate of resting eggs submitted to hypochlorite solution (47.2 ± 7.34%) and manually decapsulated (53.7 ± 13.24%). However, the immersion in hypochlorite was a more efficient technique, faster and not requiring manual ability.(AU)

Cladóceros são capazes de produzir ovos de resistência envoltos por uma cápsula protetora, o efípio, que dificulta a visualização do número de ovos, devido à pigmentação escura. Assim, antes da condução de experimentos de eclosão, métodos para determinar o número de ovos de resistência viáveis no interior do efípio devem ser utilizados. Este estudo teve como objetivo avaliar o número de ovos por efípio de Daphnia de dois ecossistemas aquáticos tropicais e a eficiência de alguns métodos de desencapsulamento de ovos de resistência. Para avaliar a influência dos métodos na taxa de eclosão foram testadas três condições: imersão em hipoclorito de sódio, ovos de resistência desencapsulados manualmente e efípios intactos. A imersão em solução de hipoclorito permitiu avaliar as diferenças no número de ovos de resistência por efípios entre os ecossistemas. A exposição ao hipoclorito de sódio a uma concentração de 2% durante 20 minutos foi o método mais eficiente para a avaliação visual e isolamento dos ovos de resistência. A taxa de eclosão de ovos não isolados de efípios foi subestimada (11,1 ± 5,0%), mostrando a necessidade de métodos para quantificação e isolamento dos ovos. Não foi verificada diferença de eclosão entre os ovos isolados a partir da imersão em solução de hipoclorito (47,2 ± 7,34%) e manualmente desencapsulados (53,7 ± 13,24%). Entretanto, a imersão em hipoclorito é uma técnica mais eficiente, pois além de mais rápida, não necessita de destreza manual.(AU)

Assuntos

RESUMO

Abstract Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a “quilombola” community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.

Resumo O conhecimento local acerca da biodiversidade vem sendo utilizado em pesquisas voltadas ao uso e manejo de recursos naturais aliados à conservação. Entre estes recursos, destaca-se o Pequi (Caryocar brasiliense Cambess.) devido à sua importância econômica e alimentar para comunidades que vivem no Cerrado. No quilombo de Pontinha, localizado na região central do estado de Minas Gerais, um estudo etnoecológico sobre o Pequi foi desenvolvido, a fim de subsidiar iniciativas de geração de trabalho e renda para esta comunidade. Informações foram obtidas por meio de entrevistas semiestruturadas, observação participante e travessia. Alimentação familiar (97%), produção de sabão (67%), produção de óleo (37%), tratamento medicinal (17%) e comércio (3%) foram os principais usos do Pequi citados pelos comunitários. Abelhas foram os visitantes florais com maior Índice de Saliência (S=0,639). Dentre os frugívoros que se alimentam de frutos não caídos, as aves apresentaram maior Saliência (S=0,359) e os insetos foram os mais importantes frugívoros entre os que utilizam frutos caídos (S=0,574). Brocas, lagartas folívoras e que atacam troncos e raízes foram as pragas mais citadas. Os indivíduos jovens de Pequi são, segundo os entrevistados, os mais afetados pelo fogo devido ao menor porte e por ter a casca menos espessa. O reconhecimento da importância cultural e ecológica do Pequi tem mobilizado a comunidade, que demonstra interesse em fazer dessa espécie uma alternativa de renda.

Assuntos

RESUMO

Abstract Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a quilombola community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.(AU)

Resumo O conhecimento local acerca da biodiversidade vem sendo utilizado em pesquisas voltadas ao uso e manejo de recursos naturais aliados à conservação. Entre estes recursos, destaca-se o Pequi (Caryocar brasiliense Cambess.) devido à sua importância econômica e alimentar para comunidades que vivem no Cerrado. No quilombo de Pontinha, localizado na região central do estado de Minas Gerais, um estudo etnoecológico sobre o Pequi foi desenvolvido, a fim de subsidiar iniciativas de geração de trabalho e renda para esta comunidade. Informações foram obtidas por meio de entrevistas semiestruturadas, observação participante e travessia. Alimentação familiar (97%), produção de sabão (67%), produção de óleo (37%), tratamento medicinal (17%) e comércio (3%) foram os principais usos do Pequi citados pelos comunitários. Abelhas foram os visitantes florais com maior Índice de Saliência (S=0,639). Dentre os frugívoros que se alimentam de frutos não caídos, as aves apresentaram maior Saliência (S=0,359) e os insetos foram os mais importantes frugívoros entre os que utilizam frutos caídos (S=0,574). Brocas, lagartas folívoras e que atacam troncos e raízes foram as pragas mais citadas. Os indivíduos jovens de Pequi são, segundo os entrevistados, os mais afetados pelo fogo devido ao menor porte e por ter a casca menos espessa. O reconhecimento da importância cultural e ecológica do Pequi tem mobilizado a comunidade, que demonstra interesse em fazer dessa espécie uma alternativa de renda.(AU)

Assuntos

RESUMO

Cladocerans are able to produce resting eggs inside a protective resistant capsule, the ephippium, that difficults the visualization of the resting eggs, because of the dark pigmentation. Therefore, before hatching experiments, methods to verify viable resting eggs in ephippia must be considered. This study aimed to evaluate the number of eggs per ephippium of Daphnia from two tropical aquatic ecosystems and the efficiency of some methods for decapsulating resting eggs. To evaluate the influence of methods on hatching rates, three different conditions were tested: immersion in sodium hypochlorite, manually decapsulated resting eggs and intact ephippia. The immersion in hypochlorite solution could evaluate differences in numbers of resting eggs per ephippium between the ecosystems studied. The exposure to sodium hypochlorite at a concentration of 2% for 20 minutes was the most efficient method for visual evaluation and isolation of the resting eggs. Hatching rate experiments with resting eggs not isolated from ephippia were underestimated (11.1 ± 5.0%), showing the need of methods to quantify and isolate viable eggs. There were no differences between the hatching rate of resting eggs submitted to hypochlorite solution (47.2 ± 7.34%) and manually decapsulated (53.7 ± 13.24%). However, the immersion in hypochlorite was a more efficient technique, faster and not requiring manual ability.

Assuntos

RESUMO

Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a "quilombola" community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.

Assuntos

RESUMO

The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

Assuntos

RESUMO

Abstract The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

Resumo A introdução de espécies tornou-se um importante problema para a conservação da biodiversidade e dos ecossistemas naturais. O sistema de lagos do médio Rio Doce (MG, Brasil) compreende cerca de 200 lagos em vários estados de conservação, dos quais 50 estão localizados dentro do Parque Estadual do Rio Doce (PERD). Estudos anteriores demonstraram que vários desses lagos sofreram introduções de peixes não nativos. Este estudo discute os efeitos das espécies de peixes não nativos na maior unidade de conservação da Mata Atlântica em Minas Gerais, sudeste do Brasil, utilizando dados de 1983 até 2010, distribuídos da seguinte forma: dados de 1983 a 2005 obtidos de estudos realizados anteriormente, e dados de setembro de 2006 a julho de 2010 obtidos no lago Carioca, utilizando redes de emalhar, redes de arrasto e peneira. Um total de 17 espécies de peixes foi coletado (2006-2010), sendo cinco introduzidas. Dentre estas, Cichla kelberi (tucunaré) e Pygocentrus nattereri (piranha vermelha) estiveram dentre as mais abundantes. Entre as espécies nativas de pequeno a médio porte (30-2000 mm de comprimento padrão), duas foram novos registros e uma foi recapturada. O desaparecimento de sete destas espécies, registradas em estudos anteriores, e a baixa representatividade nas amostragens da maioria das espécies remanescentes, evidencia o alto impacto da invasão de peixes na comunidade estudada. Considerando a importância de ações de manejo de espécies não nativas visando à conservação e manutenção da biodiversidade local e regional, propõem-se a realização de pescas seletivas intensivas, juntamente com ações que previnam novas introduções, incluindo ações educativas junto às comunidades locais.

Assuntos

RESUMO

Abstract The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.(AU)

Resumo A introdução de espécies tornou-se um importante problema para a conservação da biodiversidade e dos ecossistemas naturais. O sistema de lagos do médio Rio Doce (MG, Brasil) compreende cerca de 200 lagos em vários estados de conservação, dos quais 50 estão localizados dentro do Parque Estadual do Rio Doce (PERD). Estudos anteriores demonstraram que vários desses lagos sofreram introduções de peixes não nativos. Este estudo discute os efeitos das espécies de peixes não nativos na maior unidade de conservação da Mata Atlântica em Minas Gerais, sudeste do Brasil, utilizando dados de 1983 até 2010, distribuídos da seguinte forma: dados de 1983 a 2005 obtidos de estudos realizados anteriormente, e dados de setembro de 2006 a julho de 2010 obtidos no lago Carioca, utilizando redes de emalhar, redes de arrasto e peneira. Um total de 17 espécies de peixes foi coletado (2006-2010), sendo cinco introduzidas. Dentre estas, Cichla kelberi (tucunaré) e Pygocentrus nattereri (piranha vermelha) estiveram dentre as mais abundantes. Entre as espécies nativas de pequeno a médio porte (30-2000 mm de comprimento padrão), duas foram novos registros e uma foi recapturada. O desaparecimento de sete destas espécies, registradas em estudos anteriores, e a baixa representatividade nas amostragens da maioria das espécies remanescentes, evidencia o alto impacto da invasão de peixes na comunidade estudada. Considerando a importância de ações de manejo de espécies não nativas visando à conservação e manutenção da biodiversidade local e regional, propõem-se a realização de pescas seletivas intensivas, juntamente com ações que previnam novas introduções, incluindo ações educativas junto às comunidades locais.(AU)

Assuntos

RESUMO

Abstract Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a quilombola community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income.

Resumo O conhecimento local acerca da biodiversidade vem sendo utilizado em pesquisas voltadas ao uso e manejo de recursos naturais aliados à conservação. Entre estes recursos, destaca-se o Pequi (Caryocar brasiliense Cambess.) devido à sua importância econômica e alimentar para comunidades que vivem no Cerrado. No quilombo de Pontinha, localizado na região central do estado de Minas Gerais, um estudo etnoecológico sobre o Pequi foi desenvolvido, a fim de subsidiar iniciativas de geração de trabalho e renda para esta comunidade. Informações foram obtidas por meio de entrevistas semiestruturadas, observação participante e travessia. Alimentação familiar (97%), produção de sabão (67%), produção de óleo (37%), tratamento medicinal (17%) e comércio (3%) foram os principais usos do Pequi citados pelos comunitários. Abelhas foram os visitantes florais com maior Índice de Saliência (S=0,639). Dentre os frugívoros que se alimentam de frutos não caídos, as aves apresentaram maior Saliência (S=0,359) e os insetos foram os mais importantes frugívoros entre os que utilizam frutos caídos (S=0,574). Brocas, lagartas folívoras e que atacam troncos e raízes foram as pragas mais citadas. Os indivíduos jovens de Pequi são, segundo os entrevistados, os mais afetados pelo fogo devido ao menor porte e por ter a casca menos espessa. O reconhecimento da importância cultural e ecológica do Pequi tem mobilizado a comunidade, que demonstra interesse em fazer dessa espécie uma alternativa de renda.

RESUMO

Abstract The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

Resumo A introdução de espécies tornou-se um importante problema para a conservação da biodiversidade e dos ecossistemas naturais. O sistema de lagos do médio Rio Doce (MG, Brasil) compreende cerca de 200 lagos em vários estados de conservação, dos quais 50 estão localizados dentro do Parque Estadual do Rio Doce (PERD). Estudos anteriores demonstraram que vários desses lagos sofreram introduções de peixes não nativos. Este estudo discute os efeitos das espécies de peixes não nativos na maior unidade de conservação da Mata Atlântica em Minas Gerais, sudeste do Brasil, utilizando dados de 1983 até 2010, distribuídos da seguinte forma: dados de 1983 a 2005 obtidos de estudos realizados anteriormente, e dados de setembro de 2006 a julho de 2010 obtidos no lago Carioca, utilizando redes de emalhar, redes de arrasto e peneira. Um total de 17 espécies de peixes foi coletado (2006-2010), sendo cinco introduzidas. Dentre estas, Cichla kelberi (tucunaré) e Pygocentrus nattereri (piranha vermelha) estiveram dentre as mais abundantes. Entre as espécies nativas de pequeno a médio porte (30-2000 mm de comprimento padrão), duas foram novos registros e uma foi recapturada. O desaparecimento de sete destas espécies, registradas em estudos anteriores, e a baixa representatividade nas amostragens da maioria das espécies remanescentes, evidencia o alto impacto da invasão de peixes na comunidade estudada. Considerando a importância de ações de manejo de espécies não nativas visando à conservação e manutenção da biodiversidade local e regional, propõem-se a realização de pescas seletivas intensivas, juntamente com ações que previnam novas introduções, incluindo ações educativas junto às comunidades locais.

RESUMO

The Ibirité reservoir is an urban and eutrophic environment, with regular occurrences of cyanobacteria blooms. The reservoir is warm monomict and remains stratified most of the year, circulating in the dry season (winter). During the hydrological cycle of October/07 to October/08 there were four scenarios with different environmental conditions, which influenced the structure of the zooplankton community, as confirmed in a previous study. Changes in the zooplankton community structure between the scenarios were studied, aiming at analyzing the stability and persistence of this community. The Spearman's coefficient of correlation was used to measure the stability; the persistence was evaluated through a cluster analysis and changes in community composition were estimated by the "temporal" ß diversity index. Considering the distribution patterns of abundance, the community was stable only in the transition between scenarios 1 and 2 (n = 30, r = 0.71, p = 0.00001), when there were no cyanobacteria blooms. The persistence of zooplankton between the scenarios was low, showing a distinct species composition for each scenario. The highest variations in species composition, observed by the values of temporal ß diversity index, were the transitions between scenarios 3-0 (1.45) and 0-1 (1.05), and the lowest variations occurred in the transition between scenarios 1-2 (0.57). The results suggest that the cyanobacteria blooms at Ibirité reservoir are be acting as "selective filters", and are, thus, disturbances with sufficient ability to change the structure of the zooplankton community.

Assuntos

RESUMO

The Ibirité reservoir is an urban and eutrophic environment, with regular occurrences of cyanobacteria blooms. The reservoir is warm monomict and remains stratified most of the year, circulating in the dry season (winter). During the hydrological cycle of October/07 to October/08 there were four scenarios with different environmental conditions, which influenced the structure of the zooplankton community, as confirmed in a previous study. Changes in the zooplankton community structure between the scenarios were studied, aiming at analyzing the stability and persistence of this community. The Spearmans coefficient of correlation was used to measure the stability; the persistence was evaluated through a cluster analysis and changes in community composition were estimated by the "temporal" β diversity index. Considering the distribution patterns of abundance, the community was stable only in the transition between scenarios 1 and 2 (n = 30, r = 0.71, p = 0.00001), when there were no cyanobacteria blooms. The persistence of zooplankton between the scenarios was low, showing a distinct species composition for each scenario. The highest variations in species composition, observed by the values of temporal β diversity index, were the transitions between scenarios 3-0 (1.45) and 0-1 (1.05), and the lowest variations occurred in the transition between scenarios 1-2 (0.57). The results suggest that the cyanobacteria blooms at Ibirité reservoir are be acting as "selective filters", and are, thus, disturbances with sufficient ability to change the structure of the zooplankton community. Keywords Urban Reservoir, zooplankton, bloom of cyanobacteria, stability, persistence. .(AU)

O reservatório de Ibirité é um ambiente urbano, eutrófico com periódicas ocorrências de florações de cianobactérias. O padrão de mistura deste reservatório é monomítico quente, permanecendo estratificado a maior parte do ano, circulando na estação seca (inverno). Durante o ciclo hidrológico de outubro/07 a outubro/08, ocorreram quatro cenários com condições ambientais distintas, que influenciaram na estruturação da comunidade zooplanctônica, conforme observado em estudo prévio. As mudanças na estrutura da comunidade zooplanctônica entre os cenários foram estudadas objetivando analisar a estabilidade e persistência desta comunidade. O coeficiente de correlação de Spearman foi utilizado para medir a estabilidade; a persistência foi considerada por meio de uma análise de agrupamento; e as mudanças na composição da comunidade foram estimadas através do índice de diversidade β temporal. A comunidade foi estável, considerando os padrões de distribuição da abundância, somente na transição entre os cenários 1 e 2 (n=30; r= 0,71; p=0,00001), nos quais não foram observadas florações de cianobactérias. A persistência do zooplâncton entre os cenários foi baixa, apresentando composições de espécies distintas. As maiores variações na composição das espécies, estimadas através dos valores de diversidade β temporal, foram nas transições entre os cenários 3-0 (1,45) e 0-1 (1,05), e o menor valor na transição entre os cenários 1-2 (0,57). Os resultados do presente trabalho sugerem que as florações de cianobactérias no reservatório de Ibirité estariam funcionando como “filtros seletivos”, ou seja, distúrbios com capacidade suficiente para alterar a estrutura da comunidade zooplanctônica.(AU)

Assuntos

RESUMO

The effect of dormancy in zooplankton populations is still unknown, largely because of the lack of methods to estimate hatching and production of the dormant stages. This study aimed to compare the production and hatching rates of ephippia of Daphnia laevis between thermal stratification and mixing periods in Jacaré Lake (Middle Rio Doce, Minas Gerais, Brazil). For this, we collected ephippia on the sediment with core sampler and we created a device called the "Ephippial Collector". There was a significant difference in ephippia hatching in situ between stratification and mixing periods (Pearson's Chi-squared test p <0.001), being higher in the second one. Significant differences in the hatching rates between periods was observed in the laboratory only for ephippia collected with Ephippial Collectors (Pearson's Chi-squared test p <0.001), being higher during the mixing period (∼ 8%). The core sample allows the collection of a certain fraction of the sediment that may contain a mixture of ephippia produced in different periods, i.e., may contain old and not viable ephippia, which masks the hatching rate. Thus, seasonality in hatching rates of ephippia was reported only by Ephippial Collectors. The higher hatching rate observed during the mixing period in the lake suggests that individuals hatched from ephippia may contribute to the increase in the population of D. laevis in the water column at this time.

Assuntos

Assuntos

RESUMO

The effect of dormancy in zooplankton populations is still unknown, largely because of the lack of methods to estimate hatching and production of the dormant stages. This study aimed to compare the production and hatching rates of ephippia of Daphnia laevis between thermal stratification and mixing periods in Jacaré Lake (Middle Rio Doce, Minas Gerais, Brazil). For this, we collected ephippia on the sediment with core sampler and we created a device called the “Ephippial Collector”. There was a significant difference in ephippia hatching in situ between stratification and mixing periods (Pearson's Chi-squared test p <0.001), being higher in the second one. Significant differences in the hatching rates between periods was observed in the laboratory only for ephippia collected with Ephippial Collectors (Pearson's Chi-squared test p <0.001), being higher during the mixing period (∼8%). The core sample allows the collection of a certain fraction of the sediment that may contain a mixture of ephippia produced in different periods, i.e., may contain old and not viable ephippia, which masks the hatching rate. Thus, seasonality in hatching rates of ephippia was reported only by Ephippial Collectors. The higher hatching rate observed during the mixing period in the lake suggests that individuals hatched from ephippia may contribute to the increase in the population of D. laevis in the water column at this time.(AU)

O efeito de dormência nas populações zooplanctônicas é ainda desconhecido, em grande parte devido à falta de metodologias para estimar a produção e eclosão de formas dormentes. Esse trabalho teve como objetivo comparar as taxas de produção e eclosão de efípios de Daphnia laevis entre períodos de estratificação térmica e de mistura na lagoa Jacaré (Médio Rio Doce, Minas Gerais, Brasil). Para isso, foi coletado efípios no sedimento com amostrador “corer” e foi criado um aparato denominado “Coletor de Efípios”. Houve diferença significativa na eclosão de efípios in situ entre período de estratificação térmica e de mistura (Pearson's Chi-squared test p<0.001), sendo maior no segundo. Diferenças significativas nas taxas de eclosão em laboratório entre os períodos foram observadas somente para os efípios coletados com os Coletores de Efípios (Pearson's Chi-squared test p<0.001), sendo maiores durante período de mistura (∼8%). O amostrador “corer” permite a coleta de determinada fração do sedimento que pode conter uma mistura de efípios produzidos em períodos distintos, ou seja, pode conter efípios antigos e não mais viáveis, o que mascara a taxa de eclosão. Dessa forma, a sazonalidade nas taxas de eclosão dos efípios foi constatada apenas pelos Coletores de Efípios. A maior taxa de eclosão observada em período de mistura do lago sugere que os indivíduos eclodidos dos efípios podem contribuir para o aumento da população de D. laevis na coluna de água nesta época.(AU)

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