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1.
Acta sci., Biol. sci ; Acta sci., Biol. sci;35(4): 513-519, out.-dez. 2013.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460761

RESUMO

We aimed to access the knowledge of the structure of the periphytic algae community on a floating substrate, the macrophyte Ricciocarpus natans (L.) Corda, during two hydrological periods in a connected environment at the Paraná river floodplain. Attached algal was removed from the substrate with the aid of a soft-bristled brush and distilled water jets and was fixed immediately for qualitative and quantitative analysis. The total richness of the periphytic algae was 188 taxa. February showed the highest species richness (154 taxa), while total species density exhibited an inverse pattern, with the highest values occurring in June (273.4 103ind. cm-2). Bacillariophyceae comprised the largest fraction of density, which was reflected by the abundance of Achnanthidium minutissimum (Kütz.) Czarn. Community structure of periphytic algae in R. natans followed the same pattern of other substrates, as previously determined. This suggests that main factor acting on the structure of periphyton at the Paraná river floodplain is primarily the floodpulses regime. The hydrochoric dispersion of R. natans across the various environments comprising the floodplain favors its communities associated, as the periphytic algae, subject to passive transport via water movement. Floating rhizoids of R. natans also may act as a mesh retainer, promoting the colonization of many metaphytic and planktonic s

2.
Acta Sci. Biol. Sci. ; 35(4): 513-519, 2013.
Artigo em Português | VETINDEX | ID: vti-725561

RESUMO

We aimed to access the knowledge of the structure of the periphytic algae community on a floating substrate, the macrophyte Ricciocarpus natans (L.) Corda, during two hydrological periods in a connected environment at the Paraná river floodplain. Attached algal was removed from the substrate with the aid of a soft-bristled brush and distilled water jets and was fixed immediately for qualitative and quantitative analysis. The total richness of the periphytic algae was 188 taxa. February showed the highest species richness (154 taxa), while total species density exhibited an inverse pattern, with the highest values occurring in June (273.4 103ind. cm-2). Bacillariophyceae comprised the largest fraction of density, which was reflected by the abundance of Achnanthidium minutissimum (Kütz.) Czarn. Community structure of periphytic algae in R. natans followed the same pattern of other substrates, as previously determined. This suggests that main factor acting on the structure of periphyton at the Paraná river floodplain is primarily the floodpulses regime. The hydrochoric dispersion of R. natans across the various environments comprising the floodplain favors its communities associated, as the periphytic algae, subject to passive transport via water movement. Floating rhizoids of R. natans also may act as a mesh retainer, promoting the colonization of many metaphytic and planktonic s

3.
Acta sci., Biol. sci ; Acta sci., Biol. sci;34(4): 419-429, Oct.-Dec. 2012.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460741

RESUMO

The aim of this study is to evaluate the kinetics of aerobic decomposition of Saccharum officinarum and Talauma ovata leaves. For each species, decomposition chambers (leaves and water) were set up, which were maintained under controlled conditions. Each sampling day (1, 7, 15, 30, 39, 58, 72 and 90 days), the concentrations of total organic carbon, pH and electrical conductivity (EC) were determined in the dissolved fraction, while the mass and cell wall fractions (CWF) were determined in the particulate fraction. The pH stabilization of the chambers with T. ovata and S. officinarum leaves occurred in alkaline (ca. 8 - 8.5) and close to the neutrality (ca. 7 - 7.5) environment, respectively. The EC values were on average 1.6 times higher in incubations with T. ovata leaves. The mass loss did not differ between the species (mean = 53.85%), however the decay coefficient was higher for S. officinarum (k4 = 0.007 day-1) than for T. ovata (k4 = 0.005 day-1) leaves. The CWF mass loss (mean = 50.16%) and their coefficient (0.0090 day-1) were similar. S. officinarum decomposed faster due to its high concentrations of energetic compounds of interest to the microbiota. The slower decomposition of T. ovata may have occurred due to the presence of secondary compounds with negative effects to the microorganisms.

4.
Acta sci., Biol. sci ; Acta sci., Biol. sci;34(2): 173-179, Apr.-June 2012.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460711

RESUMO

The objective of the present study was to investigate the influence of domestic sewage on the water along the Camandocaia River. The limnological variables analyzed were: pH, turbidity, color, manganese, iron, dissolved oxygen, nitrogen and total phosphorus. The data are discussed in terms of average values, and the Principal Component Analysis was employed. At no point were the oxygen saturation values below 70%, with the exception of point 9 (38.8%). The lowest nitrogen values were detected in points 1 to 3 (0.18 to 0.21 mg L-1) and the highest in points 9 and 10 (1.29 and 1.79 mg L-1); the highest phosphorus value was detected in point 9 (345.5 µg L-1). All variables correlate positively to the principal component 1, with the exception of oxygen saturation. The sum of the two principal components explains 86.6% of total variation found. The water of the river was little impacted by domestic sewage until Amparo. The highest levels of pollution were detected at the end of that city, and the trend was partial self-depuration until confluence with the Jaguary River. Nevertheless, the most polluted point of the river, when compared to other polluted rivers, presented lower pollution levels.


Investigar a influência do esgoto orgânico na água do rio Camandocaia. Foram analisadas as seguintes variáveis limnológicas: pH, turbidez, cor, manganês, ferro, oxigênio dissolvido, nitrogênio e fósforo totais. Os dados são discutidos em termos de valores médios e foi aplicada a Análise de Componentes Principais. Em nenhum dos 12 pontos estudados, os valores de saturação de oxigênio estiveram abaixo de 70%, com exceção do Ponto 9 (38,8%). Os menores valores de nitrogênio foram detectados nos Pontos 1 a 3 (0,18 a 0,21 mg L-1) e os valores mais elevados nos Pontos 9 e 10 (1,29 e 1,79 mg L-1); o valor mais elevado de fósforo foi detectado no Ponto 9 (345,5 µg L-1). Todas as variáveis correlacionam-se positivamente ao componente principal 1, com exceção da saturação de oxigênio. Os dois componentes principais somados explicam 86,6% do total da variação encontrada. A água do Camandocaia foi pouco impactada pelos esgotos até Amparo. No final dessa cidade foram detectados os níveis mais elevados de poluição, e a tendência foi a depuração parcial do esgoto até a confluência com o rio Jaguari. Entretanto, o local mais poluído do rio, quando comparado a outros rios poluídos, apresentou níveis de poluição inferiores.

5.
Acta sci., Biol. sci ; Acta sci., Biol. sci;34(2): 155-162, Apr.-June 2012.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460718

RESUMO

The present study aimed to inventory of bats species present in an urban area, located within the main campus of the State University of Maringá, northwestern Paraná State, and to present data on the diet, reproduction, and activity times of the captured species. Collections were performed monthly, between September 2007 and August 2008, and 377 individuals were captured, belonging to four species from the Phyllostomidae family: Artibeus lituratus (90%), Platyrrhinus lineatus (6.4%), Sturnira lilium (2.4%), and Carollia perspicillata (1.3%). The types of fruit ingested consisted especially of Cecropiaceae, Moraceae, Myrtaceae, Piperaceae and Solanaceae. Among the captured exemplars, 51% were female and 49% male. No pregnant females of A. lituratus or males with descended testicles were captured in autumn, and the largest recorded numbers of these groups were verified in winter. With regard to lactating females, A. lituratus was sampled year-round, with predominance during the warmer season. In spite of the low species diversity, the campus area is used by frugivore species that are generalists and are able to feed and reproduce in urbanized areas. In order to increase that diversity, management programs should be implemented so that urbanization and Chiroptera diversity can coexist with lower risks and losses to ecosystems.

6.
Acta sci., Biol. sci ; Acta sci., Biol. sci;34(1): 59-68, Jan.-Mar. 2012.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460691

RESUMO

This work aimed to study the structure of functional groups of entomofauna associated to aquatic macrophytes in Correntoso river, Rio Negro sub-region, Pantanal, Mato Grosso do Sul State, Brazil. Six samples were taken in different seasonal periods; ebb, dry and wet. The organisms were collected using D net (300 m mesh), sweeping five times through the roots of macrophyte banks at each sample session. Three environments were compared (open, intermediary, close) using data from six collection sites, through which were analyzed absolute abundance, observed richness of families and the sampled specimens were also separated in functional groups. A total of 60 families from 12 orders of Insecta were registered, totaling 19,773 sampled insects. The largest number of families was categorized into predators functional group, with 34 families collected, followed by the collectors with 17, shredders-herbivores ten and scrapers eight.

7.
Acta Sci. Biol. Sci. ; 34(2): 155-162, 2012.
Artigo em Português | VETINDEX | ID: vti-726053

RESUMO

The present study aimed to inventory of bats species present in an urban area, located within the main campus of the State University of Maringá, northwestern Paraná State, and to present data on the diet, reproduction, and activity times of the captured species. Collections were performed monthly, between September 2007 and August 2008, and 377 individuals were captured, belonging to four species from the Phyllostomidae family: Artibeus lituratus (90%), Platyrrhinus lineatus (6.4%), Sturnira lilium (2.4%), and Carollia perspicillata (1.3%). The types of fruit ingested consisted especially of Cecropiaceae, Moraceae, Myrtaceae, Piperaceae and Solanaceae. Among the captured exemplars, 51% were female and 49% male. No pregnant females of A. lituratus or males with descended testicles were captured in autumn, and the largest recorded numbers of these groups were verified in winter. With regard to lactating females, A. lituratus was sampled year-round, with predominance during the warmer season. In spite of the low species diversity, the campus area is used by frugivore species that are generalists and are able to feed and reproduce in urbanized areas. In order to increase that diversity, management programs should be implemented so that urbanization and Chiroptera diversity can coexist with lower risks and losses to ecosystems.

8.
Acta Sci. Biol. Sci. ; 34(4): 419-429, 2012.
Artigo em Português | VETINDEX | ID: vti-725765

RESUMO

The aim of this study is to evaluate the kinetics of aerobic decomposition of Saccharum officinarum and Talauma ovata leaves. For each species, decomposition chambers (leaves and water) were set up, which were maintained under controlled conditions. Each sampling day (1, 7, 15, 30, 39, 58, 72 and 90 days), the concentrations of total organic carbon, pH and electrical conductivity (EC) were determined in the dissolved fraction, while the mass and cell wall fractions (CWF) were determined in the particulate fraction. The pH stabilization of the chambers with T. ovata and S. officinarum leaves occurred in alkaline (ca. 8 - 8.5) and close to the neutrality (ca. 7 - 7.5) environment, respectively. The EC values were on average 1.6 times higher in incubations with T. ovata leaves. The mass loss did not differ between the species (mean = 53.85%), however the decay coefficient was higher for S. officinarum (k4 = 0.007 day-1) than for T. ovata (k4 = 0.005 day-1) leaves. The CWF mass loss (mean = 50.16%) and their coefficient (0.0090 day-1) were similar. S. officinarum decomposed faster due to its high concentrations of energetic compounds of interest to the microbiota. The slower decomposition of T. ovata may have occurred due to the presence of secondary compounds with negative effects to the microorganisms.  

9.
Acta Sci. Biol. Sci. ; 34(2): 173-179, 2012.
Artigo em Português | VETINDEX | ID: vti-725685

RESUMO

The objective of the present study was to investigate the influence of domestic sewage on the water along the Camandocaia River. The limnological variables analyzed were: pH, turbidity, color, manganese, iron, dissolved oxygen, nitrogen and total phosphorus. The data are discussed in terms of average values, and the Principal Component Analysis was employed. At no point were the oxygen saturation values below 70%, with the exception of point 9 (38.8%). The lowest nitrogen values were detected in points 1 to 3 (0.18 to 0.21 mg L-1) and the highest in points 9 and 10 (1.29 and 1.79 mg L-1); the highest phosphorus value was detected in point 9 (345.5 µg L-1). All variables correlate positively to the principal component 1, with the exception of oxygen saturation. The sum of the two principal components explains 86.6% of total variation found. The water of the river was little impacted by domestic sewage until Amparo. The highest levels of pollution were detected at the end of that city, and the trend was partial self-depuration until confluence with the Jaguary River. Nevertheless, the most polluted point of the river, when compared to other polluted rivers, presented lower pollution levels.


Investigar a influência do esgoto orgânico na água do rio Camandocaia. Foram analisadas as seguintes variáveis limnológicas: pH, turbidez, cor, manganês, ferro, oxigênio dissolvido, nitrogênio e fósforo totais. Os dados são discutidos em termos de valores médios e foi aplicada a Análise de Componentes Principais. Em nenhum dos 12 pontos estudados, os valores de saturação de oxigênio estiveram abaixo de 70%, com exceção do Ponto 9 (38,8%). Os menores valores de nitrogênio foram detectados nos Pontos 1 a 3 (0,18 a 0,21 mg L-1) e os valores mais elevados nos Pontos 9 e 10 (1,29 e 1,79 mg L-1); o valor mais elevado de fósforo foi detectado no Ponto 9 (345,5 µg L-1). Todas as variáveis correlacionam-se positivamente ao componente principal 1, com exceção da saturação de oxigênio. Os dois componentes principais somados explicam 86,6% do total da variação encontrada. A água do Camandocaia foi pouco impactada pelos esgotos até Amparo. No final dessa cidade foram detectados os níveis mais elevados de poluição, e a tendência foi a depuração parcial do esgoto até a confluência com o rio Jaguari. Entretanto, o local mais poluído do rio, quando comparado a outros rios poluídos, apresentou níveis de poluição inferiores.

10.
Acta Sci. Biol. Sci. ; 34(1): 59-68, 2012.
Artigo em Português | VETINDEX | ID: vti-725460

RESUMO

This work aimed to study the structure of functional groups of entomofauna associated to aquatic macrophytes in Correntoso river, Rio Negro sub-region, Pantanal, Mato Grosso do Sul State, Brazil. Six samples were taken in different seasonal periods; ebb, dry and wet. The organisms were collected using D net (300 m mesh), sweeping five times through the roots of macrophyte banks at each sample session. Three environments were compared (open, intermediary, close) using data from six collection sites, through which were analyzed absolute abundance, observed richness of families and the sampled specimens were also separated in functional groups. A total of 60 families from 12 orders of Insecta were registered, totaling 19,773 sampled insects. The largest number of families was categorized into predators functional group, with 34 families collected, followed by the collectors with 17, shredders-herbivores ten and scrapers eight.

11.
Acta sci., Biol. sci ; Acta sci., Biol. sci;33(4): 393-397, Out.-Dec. 2011.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460681

RESUMO

The present study investigates the 13C and 15N isotopic composition in frozen samples (control), samples in alcohol and in formaldehyde of Plagioscion squamosissimus and Hypophthalmus edentates. From each individual we extracted a strip of muscle from the region above the lateral line, in the dorsal fin base, that was divided into three equal parts, each one was submitted to one type of treatment: freeze control group (-15oC), conservation in alcohol 70% and fixation in formaldehyde 4%. Samples were kept under those treatments for 30 days, washed and submerged in distilled water for 4 hours. Afterwards, they were dried up in air oven at 60oC for 48 hours and macerated until the obtaining of a fine powder. A significant difference was found in isotopic values of carbon and nitrogen, between the control and the samples in alcohol and formaldehyde, except for 13C from the H. edentates samples in formaldehyde. The carbon isotopic values of samples in alcohol were mostly enriched compared to control, whereas the samples in formaldehyde presented depleted values in relation to the control. The nitrogen isotopic values for both samples preserved in alcohol and formaldehyde were enriched when compared to the values of frozen samples, independently of used preservatives. Therefore, the isotopic correction should be accomplished according to the isotope and preservative employed for


The present study investigates the 13C and 15N isotopic composition in frozen samples (control), samples in alcohol and in formaldehyde of Plagioscion squamosissimus and Hypophthalmus edentates. From each individual we extracted a strip of muscle from the region above the lateral line, in the dorsal fin base, that was divided into three equal parts, each one was submitted to one type of treatment: freeze control group (-15oC), conservation in alcohol 70% and fixation in formaldehyde 4%. Samples were kept under those treatments for 30 days, washed and submerged in distilled water for 4 hours. Afterwards, they were dried up in air oven at 60oC for 48 hours and macerated until the obtaining of a fine powder. A significant difference was found in isotopic values of carbon and nitrogen, between the control and the samples in alcohol and formaldehyde, except for 13C from the H. edentates samples in formaldehyde. The carbon isotopic values of samples in alcohol were mostly enriched compared to control, whereas the samples in formaldehyde presented depleted values in relation to the control. The nitrogen isotopic values for both samples preserved in alcohol and formaldehyde were enriched when compared to the values of frozen samples, independently of used preservatives. Therefore, the isotopic correction should be accomplished according to the isotope and preservative employed for

12.
Acta sci., Biol. sci ; Acta sci., Biol. sci;33(4): 417-426, Out.-Dec. 2011.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460684

RESUMO

The floodplain of the upper Paraná river is characterized by the great diversity of aquatic organisms, and the larvae of Chironomidae are distinguished for their high density. Starting from the hypothesis that abiotic variables influence Chironomidae larvae composition, density and dominance in different environments and sampled periods, this study aimed to characterize the Baía river, secondary channel, floodplain lakes (connected and non-connected) of the Paraná river floodplain, according to attributes of Chironomidae assemblage, and identify possible gradients of temporal and spatial distribution of the larvae, relating them with abiotic variables. The collections were carried out from March 2003 to December 2005. Samples were collected in three points (margins and center), using a modified Petersen grab. CCA showed the larvae were influenced mainly by sediment particle size. Curutuba channel, due to the presence of pebbles, differed from other sites such as the Baía river and floodplain lakes, where fine particles predominated. It was concluded that particle size composition, percentage of organic matter and hydrodynamic of each environment were the main variables that influenced the spatial distribution of Chironomidae larvae.


A planície de inundação do alto rio Paraná caracteriza-se pela grande diversidade de organismos aquáticos e as larvas de Chironomidae destacam-se por sua elevada abundância. A partir da hipótese de que as variáveis abióticas influenciam a composição, densidade e dominância das larvas de Chironomidae em diferentes ambientes e períodos amostrados, este trabalho objetivou: caracterizar o rio Baía, canal secundário, lagoa não-conectada (Fechada) e lagoa conectada (Guaraná) da planície de inundação do alto rio Paraná, de acordo com os atributos da assembléia de Chironomidae e identificar possíveis gradientes de distribuição espacial e temporal das larvas, relacionando-as com algumas variáveis abióticas. As coletas foram realizadas no período de março de 2003 a dezembro de 2005, em três pontos distintos (margens e centro), com o auxílio de um pegador tipo Petersen modificado. A Análise de Correspondência Canônica mostrou que as larvas foram influenciadas principalmente pela textura granulométrica do sedimento. O canal Curutuba, pela presença de seixos, diferenciou-se das demais estações de coleta como rio Baía e as lagoas de inundação onde predominaram as partículas mais finas. Pode-se concluir que a composição granulométrica, a porcentagem de matéria orgânica presente no sedimento e a hidrodinâmica de cada ambiente foram os principais fatores que influenciaram a distribuição espacia

13.
Acta Sci. Biol. Sci. ; 33(4): 417-426, 2011.
Artigo em Português | VETINDEX | ID: vti-725874

RESUMO

The floodplain of the upper Paraná river is characterized by the great diversity of aquatic organisms, and the larvae of Chironomidae are distinguished for their high density. Starting from the hypothesis that abiotic variables influence Chironomidae larvae composition, density and dominance in different environments and sampled periods, this study aimed to characterize the Baía river, secondary channel, floodplain lakes (connected and non-connected) of the Paraná river floodplain, according to attributes of Chironomidae assemblage, and identify possible gradients of temporal and spatial distribution of the larvae, relating them with abiotic variables. The collections were carried out from March 2003 to December 2005. Samples were collected in three points (margins and center), using a modified Petersen grab. CCA showed the larvae were influenced mainly by sediment particle size. Curutuba channel, due to the presence of pebbles, differed from other sites such as the Baía river and floodplain lakes, where fine particles predominated. It was concluded that particle size composition, percentage of organic matter and hydrodynamic of each environment were the main variables that influenced the spatial distribution of Chironomidae larvae.


A planície de inundação do alto rio Paraná caracteriza-se pela grande diversidade de organismos aquáticos e as larvas de Chironomidae destacam-se por sua elevada abundância. A partir da hipótese de que as variáveis abióticas influenciam a composição, densidade e dominância das larvas de Chironomidae em diferentes ambientes e períodos amostrados, este trabalho objetivou: caracterizar o rio Baía, canal secundário, lagoa não-conectada (Fechada) e lagoa conectada (Guaraná) da planície de inundação do alto rio Paraná, de acordo com os atributos da assembléia de Chironomidae e identificar possíveis gradientes de distribuição espacial e temporal das larvas, relacionando-as com algumas variáveis abióticas. As coletas foram realizadas no período de março de 2003 a dezembro de 2005, em três pontos distintos (margens e centro), com o auxílio de um pegador tipo Petersen modificado. A Análise de Correspondência Canônica mostrou que as larvas foram influenciadas principalmente pela textura granulométrica do sedimento. O canal Curutuba, pela presença de seixos, diferenciou-se das demais estações de coleta como rio Baía e as lagoas de inundação onde predominaram as partículas mais finas. Pode-se concluir que a composição granulométrica, a porcentagem de matéria orgânica presente no sedimento e a hidrodinâmica de cada ambiente foram os principais fatores que influenciaram a distribuição espacia

14.
Acta Sci. Biol. Sci. ; 33(4): 393-397, 2011.
Artigo em Português | VETINDEX | ID: vti-725754

RESUMO

The present study investigates the 13C and 15N isotopic composition in frozen samples (control), samples in alcohol and in formaldehyde of Plagioscion squamosissimus and Hypophthalmus edentates. From each individual we extracted a strip of muscle from the region above the lateral line, in the dorsal fin base, that was divided into three equal parts, each one was submitted to one type of treatment: freeze control group (-15oC), conservation in alcohol 70% and fixation in formaldehyde 4%. Samples were kept under those treatments for 30 days, washed and submerged in distilled water for 4 hours. Afterwards, they were dried up in air oven at 60oC for 48 hours and macerated until the obtaining of a fine powder. A significant difference was found in isotopic values of carbon and nitrogen, between the control and the samples in alcohol and formaldehyde, except for 13C from the H. edentates samples in formaldehyde. The carbon isotopic values of samples in alcohol were mostly enriched compared to control, whereas the samples in formaldehyde presented depleted values in relation to the control. The nitrogen isotopic values for both samples preserved in alcohol and formaldehyde were enriched when compared to the values of frozen samples, independently of used preservatives. Therefore, the isotopic correction should be accomplished according to the isotope and preservative employed for


The present study investigates the 13C and 15N isotopic composition in frozen samples (control), samples in alcohol and in formaldehyde of Plagioscion squamosissimus and Hypophthalmus edentates. From each individual we extracted a strip of muscle from the region above the lateral line, in the dorsal fin base, that was divided into three equal parts, each one was submitted to one type of treatment: freeze control group (-15oC), conservation in alcohol 70% and fixation in formaldehyde 4%. Samples were kept under those treatments for 30 days, washed and submerged in distilled water for 4 hours. Afterwards, they were dried up in air oven at 60oC for 48 hours and macerated until the obtaining of a fine powder. A significant difference was found in isotopic values of carbon and nitrogen, between the control and the samples in alcohol and formaldehyde, except for 13C from the H. edentates samples in formaldehyde. The carbon isotopic values of samples in alcohol were mostly enriched compared to control, whereas the samples in formaldehyde presented depleted values in relation to the control. The nitrogen isotopic values for both samples preserved in alcohol and formaldehyde were enriched when compared to the values of frozen samples, independently of used preservatives. Therefore, the isotopic correction should be accomplished according to the isotope and preservative employed for

15.
Acta Sci. Biol. Sci. ; 31(4): 355-361, 2009.
Artigo em Português | VETINDEX | ID: vti-726020

RESUMO

The dynamic of plant communities is strongly influenced by biological interactions. We studied the effects of Eichhornia azurea on the growth of the free-floating macrophytes Eichhornia crassipes, Salvinia minima, Salvinia auriculata and Limnobium laevigatum. The experiments were carried out in three lakes of the upper Paraná river floodplain. We used 0.5 m side squares where these species grew for 11 days (S. auriculata and L. laevigatum) and 17 days (E. crassipes and S. minima), in the presence and absence of E. azurea. There were no significant differences between the relative growth rates of macrophytes growing in the absence and presence of E. azurea. The relative interaction index showed the existence of competition between E. azurea and L. laevigatum, and neutrality with the other three species. There was no evidence of facilitation related to the improvement of physico-chemistry characteristics that could enhance macrophytes growth. However, we do not discard a mechanical facilitation between E. azurea, which offers protection against wind and waves, and the other species of macrophytes

16.
Acta Sci. Biol. Sci. ; 31(4): 371-377, 2009.
Artigo em Português | VETINDEX | ID: vti-725578

RESUMO

In Brazil, studies on the diet of Chironomidae larvae are still scarce and these data are important to understand the trophic structure and organization of aquatic ecosystems. In this study, we identified the main food items consumed by Cricotopus sp. and compared possible differences in the larval diet at different artificial substrates and hydrological phases. We used four types of artificial substrates: X-shaped wood (MADX); X-shaped nitacetal plates (NITX); tube-shaped PVC (PVCT) and tube-shaped galvanized metal (METT), each with three replicates. Samplings were undertaken fortnightly, between August 2004 and December 2005. Cricotopus sp. diet was composed by detritus, algae and fungal hyphae. Detritus was the main food item, with values above 50% of total intake. The results indicated that Cricotopus sp. is a collector species and, regardless of substrate, these larvae feed on available resources in the environment. However, the changes in hydrological regime of the Paraná river can influence the food resource availability, mainly some Diatoma genera such as Melosira sp., which were consumed in high quantity only during the low water phase


No Brasil, estudos sobre hábitos alimentares das larvas de Chironomidae ainda são escassos e estas informações são importantes para entender a estrutura trófica e a organização dos ecossistemas aquáticos. Neste estudo, teve-se como objetivo identificar os principais itens alimentares ingeridos por Cricotopus sp. e comparar as possíveis diferenças na dieta das larvas em diferentes substratos artificiais e fases hídricas. Foram utilizados quatro tipos de substratos artificiais: madeira em forma de X (MADX), placas de nitacetal em forma de X (NITX), PVC em forma de tubo (PVCT) e metal galvanizado em forma de tubo (METT), cada um com três réplicas. As coletas foram realizadas quinzenalmente, entre os meses de agosto de 2004 e dezembro de 2005. A dieta de Cricotopus sp. foi constituída por detritos, algas e hifas de fungos. Detrito foi o principal item alimentar, com valores superiores a 50% do total consumido. Os resultados indicaram que Cricotopus sp. é uma espécie coletora e, independentemente do substrato, as larvas alimentam-se dos recursos disponíveis no ambiente. Entretanto, mudanças no regime hidrológico do rio Paraná podem influenciar a disponibilidade de alimento, principalmente algumas diatomaceas como Melosira sp., consumidas em maior quantidade apenas na fase de águas baixas

17.
Acta Sci. Biol. Sci. ; 31(4): 407-413, 2009.
Artigo em Português | VETINDEX | ID: vti-725479

RESUMO

The objective of this study was to evaluate the impacts of fire on the tree-shrub component in an ombrophilous forest fragment in Areia, state of Paraíba, Brazil. Forty parcels were plotted in two environments: intact forest (Environment I) and burned forest (Environment II). The vegetation structure was evaluated by conventional parameters, and the difference in the number of shoots of individuals between the environments was evaluated using the Kruskal-Wallis test. Also calculated were the index of diversity, equability and the similarity between the environments. We sampled 1,960 individuals, belonging to 22 families, 26 genera and 35 species. In Environment I, Protium heptaphyllum, Cupania oblongifolia and Brosimum guianense were the most important and abundant species, while the dead individuals were the majority in Environment II. The Kruskal-Wallis test showed there were significant differences between the intact and burned environments. The indices of diversity and the equability of Environment I were greater than those found in Environment II. Nevertheless, the two environments remain similar according to the Jaccard index. The results showed that fire does not appear to change the composition of species; however, it affected the structure of the community, and increased significantly the number of shoots, indicating the death of the canopy in several individuals


O objetivo do presente trabalho foi avaliar os impactos causados pelo fogo sobre o estrato arbustivo-arbóreo de um fragmento de Floresta Atlântica, em Areia, Paraíba. Foram plotadas 40 parcelas de 100 m2 em dois ambientes: floresta intacta (Ambiente I) e floresta queimada (Ambiente II). O presente levantamento incluiu indivíduos com diâmetro ao nível do solo (DNS) 3 cm, sendo a estrutura da vegetação avaliada por parâmetros convencionais. Calcularam-se, também, os índices de diversidade e de equabilidade, além da similaridade entre os ambientes. Foram amostrados 1.960 indivíduos, pertencentes a 22 famílias, 26 gêneros e 35 espécies. No Ambiente I, Protium heptaphyllum foi a espécie mais abundante e importante; no Ambiente II, sobressaíram-se os indivíduos mortos. O teste Kruskal-Wallis (H) analisou a diferença no número de perfilhos dos indivíduos entre os Ambientes, apontando diferença significativa entre estes. O índice de diversidade e a equabilidade no Ambiente I foram maiores que no atingido pelo incêndio; pelo índice de Jaccard, porém, verificou-se que continuam similares. Os resultados demonstraram que o incêndio parece não modificar a composição específica da sinúsia, mas afeta a estrutura da comunidade, além de aumentar significativamente o perfilhamento, indicando a morte da parte aérea de muitos indivíduos

18.
Acta Sci. Biol. Sci. ; 31(2): 127-134, 2009.
Artigo em Português | VETINDEX | ID: vti-725397

RESUMO

This work aimed ato research the distribution of insects associated with aquatic macrophytes and the similarity among collection sites during the reflux period in a stretch of Correntoso river, Pantanal do Negro, Mato Grosso do Sul State, Brazil. The collection sites were determined by changes in the riparian formation structure, characterized as open when there is communication with flooded fields and intermediary and closed when there is not any communication with flooded fields. Three collections were taken at six sample sites, during reflux periods. The organisms were collected using a D net, 300 µm mesh, with samples from five nets thrown in roots of aquatic macrophytes. Family richness, absolute and relative abundance of the insects found, and similarity of collection sites were analyzed using Euclidian distance and complete connection, Shannon-Wiener diversity index, with log2. Sixty-four families from 10 orders of Hexapoda class were registered, totaling 2,525 individuals 2,405 of them aquatic and semi- aquatic, and 120 terrestrial. The collect sites did not present a fixed model of similarity, and the formation of groups occurred in distinct forms at each collection.


Este trabalho teve como objetivo pesquisar a distribuição de insetos associados a macrófitas aquáticas e a similaridade dos sítios de coleta, no período de vazante, em um trecho do rio Correntoso, Pantanal do Negro, Estado do Mato Grosso do Sul, Brasil. Os sítios de coleta foram determinados conforme a mudança na estrutura da formação ripária, caracterizados como abertos com comunicação com campos inundáveis; intermediários sem comunicação com campos inundáveis; fechados sem comunicação com campos inundáveis. Foram realizadas três coletas durante o período de vazante, em seis sítios de coletas. Os organismos foram coletados utilizando rede D com malha de 300 µm e esforço amostral de cinco lances de rede em raízes de macrófitas aquáticas. Foi analisada a riqueza de famílias, a abundância absoluta e relativa dos insetos encontrados, a similaridade dos sítios de coleta por análise de agrupamento, utilizando distância euclidiana e ligação completa, índice de diversidade de Shannon-Wienner, com log2. Foram registradas 64 famílias de dez ordens da Classe Hexapoda, totalizando 2.525 indivíduos, 2.405 aquáticos e semi-aquáticos e 120 terrestres. Os sítios de coleta não apresentaram padrão fixo de similaridade, e a formação dos grupos ocorreu de forma distinta a cada coleta.

19.
Acta sci., Biol. sci ; Acta sci., Biol. sci;31(2): 127-134, 2009.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460577

RESUMO

This work aimed ato research the distribution of insects associated with aquatic macrophytes and the similarity among collection sites during the reflux period in a stretch of Correntoso river, Pantanal do Negro, Mato Grosso do Sul State, Brazil. The collection sites were determined by changes in the riparian formation structure, characterized as open when there is communication with flooded fields and intermediary and closed when there is not any communication with flooded fields. Three collections were taken at six sample sites, during reflux periods. The organisms were collected using a D net, 300 µm mesh, with samples from five nets thrown in roots of aquatic macrophytes. Family richness, absolute and relative abundance of the insects found, and similarity of collection sites were analyzed using Euclidian distance and complete connection, Shannon-Wiener diversity index, with log2. Sixty-four families from 10 orders of Hexapoda class were registered, totaling 2,525 individuals 2,405 of them aquatic and semi- aquatic, and 120 terrestrial. The collect sites did not present a fixed model of similarity, and the formation of groups occurred in distinct forms at each collection.


Este trabalho teve como objetivo pesquisar a distribuição de insetos associados a macrófitas aquáticas e a similaridade dos sítios de coleta, no período de vazante, em um trecho do rio Correntoso, Pantanal do Negro, Estado do Mato Grosso do Sul, Brasil. Os sítios de coleta foram determinados conforme a mudança na estrutura da formação ripária, caracterizados como abertos com comunicação com campos inundáveis; intermediários sem comunicação com campos inundáveis; fechados sem comunicação com campos inundáveis. Foram realizadas três coletas durante o período de vazante, em seis sítios de coletas. Os organismos foram coletados utilizando rede D com malha de 300 µm e esforço amostral de cinco lances de rede em raízes de macrófitas aquáticas. Foi analisada a riqueza de famílias, a abundância absoluta e relativa dos insetos encontrados, a similaridade dos sítios de coleta por análise de agrupamento, utilizando distância euclidiana e ligação completa, índice de diversidade de Shannon-Wienner, com log2. Foram registradas 64 famílias de dez ordens da Classe Hexapoda, totalizando 2.525 indivíduos, 2.405 aquáticos e semi-aquáticos e 120 terrestres. Os sítios de coleta não apresentaram padrão fixo de similaridade, e a formação dos grupos ocorreu de forma distinta a cada coleta.

20.
Acta sci., Biol. sci ; Acta sci., Biol. sci;31(4): 407-413, 2009.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460609

RESUMO

The objective of this study was to evaluate the impacts of fire on the tree-shrub component in an ombrophilous forest fragment in Areia, state of Paraíba, Brazil. Forty parcels were plotted in two environments: intact forest (Environment I) and burned forest (Environment II). The vegetation structure was evaluated by conventional parameters, and the difference in the number of shoots of individuals between the environments was evaluated using the Kruskal-Wallis test. Also calculated were the index of diversity, equability and the similarity between the environments. We sampled 1,960 individuals, belonging to 22 families, 26 genera and 35 species. In Environment I, Protium heptaphyllum, Cupania oblongifolia and Brosimum guianense were the most important and abundant species, while the dead individuals were the majority in Environment II. The Kruskal-Wallis test showed there were significant differences between the intact and burned environments. The indices of diversity and the equability of Environment I were greater than those found in Environment II. Nevertheless, the two environments remain similar according to the Jaccard index. The results showed that fire does not appear to change the composition of species; however, it affected the structure of the community, and increased significantly the number of shoots, indicating the death of the canopy in several individuals


O objetivo do presente trabalho foi avaliar os impactos causados pelo fogo sobre o estrato arbustivo-arbóreo de um fragmento de Floresta Atlântica, em Areia, Paraíba. Foram plotadas 40 parcelas de 100 m2 em dois ambientes: floresta intacta (Ambiente I) e floresta queimada (Ambiente II). O presente levantamento incluiu indivíduos com diâmetro ao nível do solo (DNS) 3 cm, sendo a estrutura da vegetação avaliada por parâmetros convencionais. Calcularam-se, também, os índices de diversidade e de equabilidade, além da similaridade entre os ambientes. Foram amostrados 1.960 indivíduos, pertencentes a 22 famílias, 26 gêneros e 35 espécies. No Ambiente I, Protium heptaphyllum foi a espécie mais abundante e importante; no Ambiente II, sobressaíram-se os indivíduos mortos. O teste Kruskal-Wallis (H) analisou a diferença no número de perfilhos dos indivíduos entre os Ambientes, apontando diferença significativa entre estes. O índice de diversidade e a equabilidade no Ambiente I foram maiores que no atingido pelo incêndio; pelo índice de Jaccard, porém, verificou-se que continuam similares. Os resultados demonstraram que o incêndio parece não modificar a composição específica da sinúsia, mas afeta a estrutura da comunidade, além de aumentar significativamente o perfilhamento, indicando a morte da parte aérea de muitos indivíduos

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