Rosseval Leite | Instituto Nacional de Pesquisas da Amazônia (original) (raw)
Papers by Rosseval Leite
Fig. 2. Mean levels of total mercury in fish from different trophic categories in the Lago Grande... more Fig. 2. Mean levels of total mercury in fish from different trophic categories in the Lago Grande de Manacapuru, in the Amazon floodplain. DET, Detritivores; HER/FRU, Herbivores/ Frugivores; ONI, Omnivores; ONI/FRU, Omnivores/ Frugivores; ONI/INS, Omnivores/Insectivores; PLA, Planktivores; CAR/PIS, Carnivores/Piscivores; PIS, Piscivores; CAR/NEC, Carnivores/Necrophagous.
Fig. 3. Bioconcentration factor (Bf) among trophic categories in the Lago Grande de Manacapuru, i... more Fig. 3. Bioconcentration factor (Bf) among trophic categories in the Lago Grande de Manacapuru, in the Amazon floodplain. DET, Detritivores; HER/FRU, Herbivores/Frugivores; ONI, Omnivores; ONI/FRU, Omnivores/Frugivores; ONI/INS, Omnivores/Insectivores; PLA, Planktivores; CAR/PIS, Carnivores/Piscivores; PIS, Piscivores; CAR/NEC, Carnivores/Necrophagous.
Fig. 1. Map of lago Grande de Mancapuru.
Journal of Fish Biology, 2020
Analysis of feeding habits was performed for early life stages of Brachyplatystoma rousseauxii an... more Analysis of feeding habits was performed for early life stages of Brachyplatystoma rousseauxii and Brachyplatystoma filamentosum in the Madeira River, Brazil. Stomach contents of B. rousseauxii and B. filamentosum were identified and analyzed to provide the percentage of frequency of occurrence (%FO) and area (%A) and the alimentary index IAi. The order Diptera represented the most important item consumed by both species. This is the first analyses of the trophic ecology of these ecologically and economically important species of the Amazonian region in early life stages. This article is protected by copyright. All rights reserved.
The famous "four freedoms" laid out by Franklin Roosevelt were freedom of speech and religion, fr... more The famous "four freedoms" laid out by Franklin Roosevelt were freedom of speech and religion, freedom from want and fear.. .. My candidate for top of the list is freedom of memory. Most Canadians are lucky enough to enjoy extensive access to their own history, with relatively few restrictions. In far too much of the world,. .. efforts to recapture the history of war, abuse and injustice are met with denial, indifference, scorn or outright terror. Yet there are people, often survivors of atrocities, who insist on the right to remember. .. Such a man is Mateo Pablo,. . .[a] 43-year-old Chuj Maya Indian, [who witnessed] the slaughter. .. [of] his wife and two children [by the] Guatemalan army. [He] now lives in Montreal.
O conhecimento das fontes de energia para as larvas de peixes e essencial para o estudo das suas ... more O conhecimento das fontes de energia para as larvas de peixes e essencial para o estudo das suas relacoes troficas, incluindo o manejo em condicoes controladas total ou parcialmente pelo homem. Estas informacoes ainda nao existem para a maioria da ictiofauna amazonica. Assim, foi desenhado um experimento, para avaliar a dieta das larvas e quais os principais produtores primarios envolvidos na base de sua cadeia trofica. As amostragens que incluiram 5 lagos de varzea e o rio adjcente, foram feitas entre janeiro de 1993 e janeiro de 1996, usando-se redes de ictioplancton e de mao. Os principais mesohabitats ocupados pelas larvas foram amostrados e 10 especie foram estudadas, todas com importancia comercial. A dieta das larvas foi avaliada por classe de comprimento e local de captura e testada com ANOVA de dois fatores. A composicao isotopica (d13C e d15N) das larvas foi determinada para identificar as fontes autotroficas de energia para as mesmas e o seu nivel trofico. As larvas alime...
The Egyptian Journal of Hospital Medicine, 2021
Background: Syncope is defined as temporary loss of consciousness and postural tone resulting fro... more Background: Syncope is defined as temporary loss of consciousness and postural tone resulting from an abrupt transient decrease in cerebral blood flow. It is characterized by rapid onset, short duration and spontaneous complete recovery. Objective: Our study aimed to analyze the frequency of syncope due to cardiac, neurocardiogenic, neurologic, situational, psychiatric, and other causes and make a differential diagnosis of syncope types according to detailed medical history and further investigations with focus on cardiac cause as the most serious type of syncope. Patients and Methods: 125 pediatric patients were recruited from Arrhythmia Clinic in our Cardiology Unit, Sohag University Hospital. They presented with a primary complaint of syncope aged from 1year to 18 years with a mean age of 6.49 ± 3.77 years. Results: The most common diagnosis was neurocardiogenic syncope (n=76, 60.8%). Sixty-four cases (84.2%) had recurrent episodes. Epilepsy was found in Thirty-four cases (27.2%) and psychogenic pseudo-syncope affected one female child. There were fourteen cases (11.2%) with cardiac syncope: 8 patients with LQTS, one patient with CPVT, one patient with AVNRT, 2 patients with dilated cardiomyopathy, 1 patients with history of atrioventricular (AV) canal defect closure and one patient with cardiac mass. There was significant relationship between arrhythmia and cardiac syncope (p < 0.001). Exercise-induced syncopes were significantly associated with cardiac origins (p < 0.001). Positive ECG, Holter and echocardiographic findings were statistically significant for cardiac syncope (P < 0.001). Conclusion: Syncope is a common pediatric complaint. Most cases seen were resulting from benign causes, with only a small percentage because of serious medical conditions. In addition, most syncopal episodes in the pediatric population were diagnosed clinically or with minimally invasive testing, emphasizing the importance of a detailed history and physical examination.
Understanding the factors that control production of commercially important fishes in the Amazon ... more Understanding the factors that control production of commercially important fishes in the Amazon are necessary to effectively manage fisheries resources in the region. The first step of this understanding demands the identification of plants that contribute to the energy flow in fish’s food web. The objective of this study was to investigate which group of plants supports the production of Characiformes during their juvenile life phase, in which these fish inhabit an environment formed by C 3 and C 4 plants. A carbon isotope analysis was conducted for juvenile Characiformes collected from herbaceous aquatic stands of the Solimoes River floodplain. The diet of these fishes was also analyzed to identify possible trophic links. The results indicate that although C 3 plants are the main energy sources of juveniles, the juvenile stage is that the sampled species have higher contribution from group of C 4 plants. A diet analysis revealed that juveniles of Brycon amazonicus , Mylossoma dur...
Biota Amazônia ISSN 2179-5746 Understanding the factors that control production of commercially i... more Biota Amazônia ISSN 2179-5746 Understanding the factors that control production of commercially important fishes in the Amazon are necessary to effectively manage fisheries resources in the region. The first step of this understanding demands the identification of plants that contribute to the energy flow in fish's food web. The objective of this study was to investigate which group of plants supports the production of Characiformes during their juvenile life phase, in which these fish inhabit an environment formed by C and C plants. A carbon 3 4 isotope analysis was conducted for juvenile Characiformes collected from herbaceous aquatic stands of the Solimões River floodplain. The diet of these fishes was also analyzed to identify possible trophic links. The results indicate that although C plants are the main 3 energy sources of juveniles, the juvenile stage is that the sampled species have higher contribution from group of C plants. A diet 4 analysis revealed that juveniles of...
Programa de Pos-Graduacao em Desenvolvimento Regional e Meio Ambiente, Area de Concentracao em Am... more Programa de Pos-Graduacao em Desenvolvimento Regional e Meio Ambiente, Area de Concentracao em Ambiente, Saude e Sustentabilidade para obtencao de titulo de mestre em Desenvolvimento Regional e Meio Ambiente.
Revista Colombiana de Ciencia Animal - RECIA, 2013
Los cladóceros por su pequeña talla, rápido desarrollo y temprana reproducción, son utilizados ... more Los cladóceros por su pequeña talla, rápido desarrollo y temprana reproducción, son utilizados como alimento vivo en piscicultura. Este trabajo tuvo como objetivo estudiar la historia de vida de Daphnia magna y Ceriodaphnia reticulata (Crustacea - Cladocera), bajo condiciones de laboratorio para definir su potencial como alimento en piscicultura. Fueron realizados cultivos experimentales de D. magna y C. reticulata manteniendo 12 individuos por especie en recipientes independientes de 100 ml. Como alimento se utilizó seston proveniente de la ciénaga de San Marcos – Sucre, filtrado con malla de 40 μm y mantenido en dos acuarios de 25 litros. Los parámetros poblacionales fueron medidos cada 12 horas a lo largo del periodo de vida de los especímenes. El tiempo del desarrollo embrionario fue de 16 horas para C. reticulata y 24 horas para D. magna. Se obtuvieron diferencias significativas (P≥0.05) en el crecimiento poblacional, siendo mejor el desempeño de C. reticulata (fecundidad med...
Revista Colombiana de Ciencia Animal - RECIA, 2011
Aglomerados de herbáceas aquáticas constituem estruturas importantes para a complexidade e hetero... more Aglomerados de herbáceas aquáticas constituem estruturas importantes para a complexidade e heterogeneidade de habitats. Esta heterogeneidade exerce grande influência sobre as relações ecológicas entre os organismos a elas associados (LIMA E ARAÚJO-LIMA, 2004; PELICICE E AGOSTINHO, 2006). As partes submersas das macrófitas aquáticas são importantes habitats para diversos grupos de organismos (SÁNCHES-BOTERO et al., 2003), especialmente para peixes, que utilizam o substrato para desova, forrageamento e refúgio contra predadores (PELICICE E AGOSTINHO, 2006).
Fish and Fisheries, 2018
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
PeerJ, 2017
The boundary zone between two different hydrological regimes is often a biologically enriched env... more The boundary zone between two different hydrological regimes is often a biologically enriched environment with distinct planktonic communities. In the center of the Amazon River basin, muddy white water of the Amazon River meets with black water of the Negro River, creating a conspicuous visible boundary spanning over 10 km along the Amazon River. Here, we tested the hypothesis that the confluence boundary between the white and black water rivers concentrates prey and is used as a feeding habitat for consumers by investigating the density, biomass and distribution of mesozooplankton and ichthyoplankton communities across the two rivers during the rainy season. Our results show that mean mesozooplankton density (2,730 inds. m(-3)) and biomass (4.8 mg m(-3)) were higher in the black-water river compared to the white-water river (959 inds. m(-3); 2.4 mg m(-3)); however an exceptionally high mesozooplankton density was not observed in the confluence boundary. Nonetheless we found the hi...
Scientific reports, Feb 6, 2017
We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (B... more We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (Brachyplatystoma rousseauxii, B. platynemum, B. juruense and B. vaillantii) based on the presence of individuals with mature gonads and conducted statistical analysis of the expected long-distance downstream migrations of their larvae and juveniles. By linking the distribution of larval, juvenile and mature adult size classes across the Amazon, the results showed: (i) that the main spawning regions of these goliath catfish species are in the western Amazon; (ii) at least three species-B. rousseauxii, B. platynemum, and B. juruense-spawn partially or mainly as far upstream as the Andes; (iii) the main spawning area of B. rousseauxii is in or near the Andes; and (iv) the life history migration distances of B. rousseauxii are the longest strictly freshwater fish migrations in the world. These results provide an empirical baseline for tagging experiments, life histories extrapolated from otol...
Caldasia, 2016
During the hydrological year from December 2007 to November 2008, monthly samplings in the pelagi... more During the hydrological year from December 2007 to November 2008, monthly samplings in the pelagic, littoral and macrophytes zones were conducted in the Lago Catalão, a floodplain lake receiving a mixture of water from Negro and Solimões Rivers, in front of Manaus city. Taxonomic composition and their relative abundance of the planktonic microcrustaceans community was studied. Natural abundances of carbon (C) and nitrogen (N) stable isotopes were measured to indicate energy sources. Cladocerans were the most abundant, with a relative abundance of 60%, followed by the calanoid and cyclopoid copepods with relative abundances of 29% and 11%, respectively. Diaphanosoma spp. was the dominant cladoceran group during all the sampling periods. Cladocerans were also represented by Moina spp., Ceriodaphnia spp. and Daphnia gessneri. Three genera of calanoid copepods were found: Notodiaptomus spp, Rhacodiaptomus spp., and Argyrodiaptomus spp. The genus Mesocyclops spp. was identified among the cyclopoid copepods. Zooplankton δ 13 C values indicated that the aquatic macrophyte zone was distinct, with a mean of-27.31‰, which was more enriched than zooplankton in the pelagic and littoral zones, where they had mean δ 13 C values of-33.11 and-34.66‰, respectively. Overall, analysis of stable isotopes showed that regardless of the pathways, the initial source of carbon for the zooplankton was phytoplankton, with a minimal participation of heterotrophic bacteria.
Acta Biologica Colombiana, 2012
Acta Biologica Colombiana, Nov 11, 2011
Fig. 2. Mean levels of total mercury in fish from different trophic categories in the Lago Grande... more Fig. 2. Mean levels of total mercury in fish from different trophic categories in the Lago Grande de Manacapuru, in the Amazon floodplain. DET, Detritivores; HER/FRU, Herbivores/ Frugivores; ONI, Omnivores; ONI/FRU, Omnivores/ Frugivores; ONI/INS, Omnivores/Insectivores; PLA, Planktivores; CAR/PIS, Carnivores/Piscivores; PIS, Piscivores; CAR/NEC, Carnivores/Necrophagous.
Fig. 3. Bioconcentration factor (Bf) among trophic categories in the Lago Grande de Manacapuru, i... more Fig. 3. Bioconcentration factor (Bf) among trophic categories in the Lago Grande de Manacapuru, in the Amazon floodplain. DET, Detritivores; HER/FRU, Herbivores/Frugivores; ONI, Omnivores; ONI/FRU, Omnivores/Frugivores; ONI/INS, Omnivores/Insectivores; PLA, Planktivores; CAR/PIS, Carnivores/Piscivores; PIS, Piscivores; CAR/NEC, Carnivores/Necrophagous.
Fig. 1. Map of lago Grande de Mancapuru.
Journal of Fish Biology, 2020
Analysis of feeding habits was performed for early life stages of Brachyplatystoma rousseauxii an... more Analysis of feeding habits was performed for early life stages of Brachyplatystoma rousseauxii and Brachyplatystoma filamentosum in the Madeira River, Brazil. Stomach contents of B. rousseauxii and B. filamentosum were identified and analyzed to provide the percentage of frequency of occurrence (%FO) and area (%A) and the alimentary index IAi. The order Diptera represented the most important item consumed by both species. This is the first analyses of the trophic ecology of these ecologically and economically important species of the Amazonian region in early life stages. This article is protected by copyright. All rights reserved.
The famous "four freedoms" laid out by Franklin Roosevelt were freedom of speech and religion, fr... more The famous "four freedoms" laid out by Franklin Roosevelt were freedom of speech and religion, freedom from want and fear.. .. My candidate for top of the list is freedom of memory. Most Canadians are lucky enough to enjoy extensive access to their own history, with relatively few restrictions. In far too much of the world,. .. efforts to recapture the history of war, abuse and injustice are met with denial, indifference, scorn or outright terror. Yet there are people, often survivors of atrocities, who insist on the right to remember. .. Such a man is Mateo Pablo,. . .[a] 43-year-old Chuj Maya Indian, [who witnessed] the slaughter. .. [of] his wife and two children [by the] Guatemalan army. [He] now lives in Montreal.
O conhecimento das fontes de energia para as larvas de peixes e essencial para o estudo das suas ... more O conhecimento das fontes de energia para as larvas de peixes e essencial para o estudo das suas relacoes troficas, incluindo o manejo em condicoes controladas total ou parcialmente pelo homem. Estas informacoes ainda nao existem para a maioria da ictiofauna amazonica. Assim, foi desenhado um experimento, para avaliar a dieta das larvas e quais os principais produtores primarios envolvidos na base de sua cadeia trofica. As amostragens que incluiram 5 lagos de varzea e o rio adjcente, foram feitas entre janeiro de 1993 e janeiro de 1996, usando-se redes de ictioplancton e de mao. Os principais mesohabitats ocupados pelas larvas foram amostrados e 10 especie foram estudadas, todas com importancia comercial. A dieta das larvas foi avaliada por classe de comprimento e local de captura e testada com ANOVA de dois fatores. A composicao isotopica (d13C e d15N) das larvas foi determinada para identificar as fontes autotroficas de energia para as mesmas e o seu nivel trofico. As larvas alime...
The Egyptian Journal of Hospital Medicine, 2021
Background: Syncope is defined as temporary loss of consciousness and postural tone resulting fro... more Background: Syncope is defined as temporary loss of consciousness and postural tone resulting from an abrupt transient decrease in cerebral blood flow. It is characterized by rapid onset, short duration and spontaneous complete recovery. Objective: Our study aimed to analyze the frequency of syncope due to cardiac, neurocardiogenic, neurologic, situational, psychiatric, and other causes and make a differential diagnosis of syncope types according to detailed medical history and further investigations with focus on cardiac cause as the most serious type of syncope. Patients and Methods: 125 pediatric patients were recruited from Arrhythmia Clinic in our Cardiology Unit, Sohag University Hospital. They presented with a primary complaint of syncope aged from 1year to 18 years with a mean age of 6.49 ± 3.77 years. Results: The most common diagnosis was neurocardiogenic syncope (n=76, 60.8%). Sixty-four cases (84.2%) had recurrent episodes. Epilepsy was found in Thirty-four cases (27.2%) and psychogenic pseudo-syncope affected one female child. There were fourteen cases (11.2%) with cardiac syncope: 8 patients with LQTS, one patient with CPVT, one patient with AVNRT, 2 patients with dilated cardiomyopathy, 1 patients with history of atrioventricular (AV) canal defect closure and one patient with cardiac mass. There was significant relationship between arrhythmia and cardiac syncope (p < 0.001). Exercise-induced syncopes were significantly associated with cardiac origins (p < 0.001). Positive ECG, Holter and echocardiographic findings were statistically significant for cardiac syncope (P < 0.001). Conclusion: Syncope is a common pediatric complaint. Most cases seen were resulting from benign causes, with only a small percentage because of serious medical conditions. In addition, most syncopal episodes in the pediatric population were diagnosed clinically or with minimally invasive testing, emphasizing the importance of a detailed history and physical examination.
Understanding the factors that control production of commercially important fishes in the Amazon ... more Understanding the factors that control production of commercially important fishes in the Amazon are necessary to effectively manage fisheries resources in the region. The first step of this understanding demands the identification of plants that contribute to the energy flow in fish’s food web. The objective of this study was to investigate which group of plants supports the production of Characiformes during their juvenile life phase, in which these fish inhabit an environment formed by C 3 and C 4 plants. A carbon isotope analysis was conducted for juvenile Characiformes collected from herbaceous aquatic stands of the Solimoes River floodplain. The diet of these fishes was also analyzed to identify possible trophic links. The results indicate that although C 3 plants are the main energy sources of juveniles, the juvenile stage is that the sampled species have higher contribution from group of C 4 plants. A diet analysis revealed that juveniles of Brycon amazonicus , Mylossoma dur...
Biota Amazônia ISSN 2179-5746 Understanding the factors that control production of commercially i... more Biota Amazônia ISSN 2179-5746 Understanding the factors that control production of commercially important fishes in the Amazon are necessary to effectively manage fisheries resources in the region. The first step of this understanding demands the identification of plants that contribute to the energy flow in fish's food web. The objective of this study was to investigate which group of plants supports the production of Characiformes during their juvenile life phase, in which these fish inhabit an environment formed by C and C plants. A carbon 3 4 isotope analysis was conducted for juvenile Characiformes collected from herbaceous aquatic stands of the Solimões River floodplain. The diet of these fishes was also analyzed to identify possible trophic links. The results indicate that although C plants are the main 3 energy sources of juveniles, the juvenile stage is that the sampled species have higher contribution from group of C plants. A diet 4 analysis revealed that juveniles of...
Programa de Pos-Graduacao em Desenvolvimento Regional e Meio Ambiente, Area de Concentracao em Am... more Programa de Pos-Graduacao em Desenvolvimento Regional e Meio Ambiente, Area de Concentracao em Ambiente, Saude e Sustentabilidade para obtencao de titulo de mestre em Desenvolvimento Regional e Meio Ambiente.
Revista Colombiana de Ciencia Animal - RECIA, 2013
Los cladóceros por su pequeña talla, rápido desarrollo y temprana reproducción, son utilizados ... more Los cladóceros por su pequeña talla, rápido desarrollo y temprana reproducción, son utilizados como alimento vivo en piscicultura. Este trabajo tuvo como objetivo estudiar la historia de vida de Daphnia magna y Ceriodaphnia reticulata (Crustacea - Cladocera), bajo condiciones de laboratorio para definir su potencial como alimento en piscicultura. Fueron realizados cultivos experimentales de D. magna y C. reticulata manteniendo 12 individuos por especie en recipientes independientes de 100 ml. Como alimento se utilizó seston proveniente de la ciénaga de San Marcos – Sucre, filtrado con malla de 40 μm y mantenido en dos acuarios de 25 litros. Los parámetros poblacionales fueron medidos cada 12 horas a lo largo del periodo de vida de los especímenes. El tiempo del desarrollo embrionario fue de 16 horas para C. reticulata y 24 horas para D. magna. Se obtuvieron diferencias significativas (P≥0.05) en el crecimiento poblacional, siendo mejor el desempeño de C. reticulata (fecundidad med...
Revista Colombiana de Ciencia Animal - RECIA, 2011
Aglomerados de herbáceas aquáticas constituem estruturas importantes para a complexidade e hetero... more Aglomerados de herbáceas aquáticas constituem estruturas importantes para a complexidade e heterogeneidade de habitats. Esta heterogeneidade exerce grande influência sobre as relações ecológicas entre os organismos a elas associados (LIMA E ARAÚJO-LIMA, 2004; PELICICE E AGOSTINHO, 2006). As partes submersas das macrófitas aquáticas são importantes habitats para diversos grupos de organismos (SÁNCHES-BOTERO et al., 2003), especialmente para peixes, que utilizam o substrato para desova, forrageamento e refúgio contra predadores (PELICICE E AGOSTINHO, 2006).
Fish and Fisheries, 2018
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
PeerJ, 2017
The boundary zone between two different hydrological regimes is often a biologically enriched env... more The boundary zone between two different hydrological regimes is often a biologically enriched environment with distinct planktonic communities. In the center of the Amazon River basin, muddy white water of the Amazon River meets with black water of the Negro River, creating a conspicuous visible boundary spanning over 10 km along the Amazon River. Here, we tested the hypothesis that the confluence boundary between the white and black water rivers concentrates prey and is used as a feeding habitat for consumers by investigating the density, biomass and distribution of mesozooplankton and ichthyoplankton communities across the two rivers during the rainy season. Our results show that mean mesozooplankton density (2,730 inds. m(-3)) and biomass (4.8 mg m(-3)) were higher in the black-water river compared to the white-water river (959 inds. m(-3); 2.4 mg m(-3)); however an exceptionally high mesozooplankton density was not observed in the confluence boundary. Nonetheless we found the hi...
Scientific reports, Feb 6, 2017
We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (B... more We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (Brachyplatystoma rousseauxii, B. platynemum, B. juruense and B. vaillantii) based on the presence of individuals with mature gonads and conducted statistical analysis of the expected long-distance downstream migrations of their larvae and juveniles. By linking the distribution of larval, juvenile and mature adult size classes across the Amazon, the results showed: (i) that the main spawning regions of these goliath catfish species are in the western Amazon; (ii) at least three species-B. rousseauxii, B. platynemum, and B. juruense-spawn partially or mainly as far upstream as the Andes; (iii) the main spawning area of B. rousseauxii is in or near the Andes; and (iv) the life history migration distances of B. rousseauxii are the longest strictly freshwater fish migrations in the world. These results provide an empirical baseline for tagging experiments, life histories extrapolated from otol...
Caldasia, 2016
During the hydrological year from December 2007 to November 2008, monthly samplings in the pelagi... more During the hydrological year from December 2007 to November 2008, monthly samplings in the pelagic, littoral and macrophytes zones were conducted in the Lago Catalão, a floodplain lake receiving a mixture of water from Negro and Solimões Rivers, in front of Manaus city. Taxonomic composition and their relative abundance of the planktonic microcrustaceans community was studied. Natural abundances of carbon (C) and nitrogen (N) stable isotopes were measured to indicate energy sources. Cladocerans were the most abundant, with a relative abundance of 60%, followed by the calanoid and cyclopoid copepods with relative abundances of 29% and 11%, respectively. Diaphanosoma spp. was the dominant cladoceran group during all the sampling periods. Cladocerans were also represented by Moina spp., Ceriodaphnia spp. and Daphnia gessneri. Three genera of calanoid copepods were found: Notodiaptomus spp, Rhacodiaptomus spp., and Argyrodiaptomus spp. The genus Mesocyclops spp. was identified among the cyclopoid copepods. Zooplankton δ 13 C values indicated that the aquatic macrophyte zone was distinct, with a mean of-27.31‰, which was more enriched than zooplankton in the pelagic and littoral zones, where they had mean δ 13 C values of-33.11 and-34.66‰, respectively. Overall, analysis of stable isotopes showed that regardless of the pathways, the initial source of carbon for the zooplankton was phytoplankton, with a minimal participation of heterotrophic bacteria.
Acta Biologica Colombiana, 2012
Acta Biologica Colombiana, Nov 11, 2011