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1.
Braz. j. biol ; 83: e273010, 2023. tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1505864

Resumo

Aquatic macroinvertebrates are integral parts of functioning wetlands, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Here, we study the community structure of benthic macroinvertebrates in four different types of lotic and lentic wetlands in the semiarid Haut Plateaux of Northeast Algeria. Macroinvertebrates and 06 physicochemical parameters were sampled in 12 sites belonging to four types of habitats (lotic river, lentic river, dams, and sebkha [saline lentic water body]) during January-December 2021. Eventually, the character lentic-lotic was the most important variable affecting the affecting invertebrate communities in the Mediterranean region. The results revealed that sebkha and dams had a lower Shannon index than lentic and lotic rivers. Non-metric multidimensional scaling analysis showed a strong overlap between the community composition in lotic and lentic sites . Howeverin the three types of aquatic groups lentic river, dam and lotic habitats showed a strong overlap between the community whereas sebkha was markedly separated. Redundancy analysis showed that water velocity and pH, were the main drivers of community structure of macroinvertebrates, revealed a strong effect with pH (F1,8=4.15, P = 0.001) and water velocity (F1,8= 3.22, P = 0.002) , separating lotic communities from those that inhabited dams, lentic rivers, and sebkhas. As conclusion, this study contributes to the better understanding of the community structure of macroinvertebrates in semiarid North Africa where wetlands have been experiencing high anthropogenic disturbance.


Macroinvertebrados aquáticos são partes integrantes de zonas úmidas em funcionamento, habitando uma diversidade de ecossistemas aquáticos onde as comunidades são espacialmente estruturadas. Os macroinvertebrados de algumas regiões mediterrâneas, como o norte da África, ainda não foram especificamente analisados. Neste trabalho, almejou-se analisar a estrutura da comunidade de macroinvertebrados bentônicos em 4 tipos diferentes de pântanos lóticos e lênticos no semiárido Haut Plateaux do nordeste da Argélia. Os macroinvertebrados e 6 parâmetros físico-químicos foram amostrados mensalmente em 12 locais pertencentes a 4 categorias de habitats diferentes (rio lótico, rio lêntico, barragens e sebkha - corpo de água salina lêntica) de janeiro a dezembro de 2021. Os resultados revelaram que sebkha e barragens tiveram um pH mais baixo do que os rios lênticos e lóticos. A análise de escala multidimensional não-métrica mostrou uma forte sobreposição entre a composição da comunidade em sítios lóticos e lênticos, mas nos 3 tipos de sítios lênticos, barragem e rio lêntico mostraram uma forte sobreposição, enquanto sebkha foi marcadamente separado. A análise de redundância mostrou que a velocidade da água e o pH foram os principais impulsionadores da estrutura da comunidade de macroinvertebrados, separando as comunidades lóticas daquelas que habitavam barragens, rios lênticos e sebkhas. Assim, à guisa de conclusão, este estudo contribui para a melhor compreensão da estrutura da comunidade de macroinvertebrados no semiárido norte da África, onde as zonas úmidas têm sofrido alta perturbação antrópica.


Assuntos
Animais , Fauna Aquática , Fauna Bentônica , Invertebrados , Argélia
2.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487496

Resumo

Abstract The Pantanal floodplains of Brazil are a region of rich biodiversity. To date, the true richness of the Pantanal avifauna has not been explored satisfactorily caused by a lack of studies in the region and, especially, by the divergence of opinion among the works published by various authors on the many species found in the region. This is due to the lack of criteria in examining records, both with regard to the reliability of the identifications and in the precise geographical allocation. Therefore, in the study, we collage findings from various studies and records created by us in the last few decades from 199 distinct locations to produce a list of birds in the Pantanal floodplains. We grouped the results into three lists: primary, secondary, and tertiary. We found that the avifauna of the Pantanal floodplain is composed of a total of 617 species, of which 571 (92%) have supporting records of occurrence (primary list) and 46 still lack documentation (secondary list). The number of species listed here for the Pantanal floodplain represents 32% of all avifauna known to the Brazilian territory. This reflects the importance of the biome, as part of the national territory, for the maintenance of a meaningful avifaunistic richness. Migratory birds (n = 183), notably northern ones (n = 43), are among the main players involved in ecological processes of nutrient cycling and dispersion of important pathogens between the two continents. With regard to conservation, 25 species are included in some category of threat in the lists of threatened species with global extinction. We hope that our list will help future researchers a more definitive approach when researching the avian fauna in this bountiful region.

3.
Pap. avulsos zool ; 61: e20216182, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1346636

Resumo

Abstract The Pantanal floodplains of Brazil are a region of rich biodiversity. To date, the true richness of the Pantanal avifauna has not been explored satisfactorily caused by a lack of studies in the region and, especially, by the divergence of opinion among the works published by various authors on the many species found in the region. This is due to the lack of criteria in examining records, both with regard to the reliability of the identifications and in the precise geographical allocation. Therefore, in the study, we collage findings from various studies and records created by us in the last few decades from 199 distinct locations to produce a list of birds in the Pantanal floodplains. We grouped the results into three lists: primary, secondary, and tertiary. We found that the avifauna of the Pantanal floodplain is composed of a total of 617 species, of which 571 (92%) have supporting records of occurrence (primary list) and 46 still lack documentation (secondary list). The number of species listed here for the Pantanal floodplain represents 32% of all avifauna known to the Brazilian territory. This reflects the importance of the biome, as part of the national territory, for the maintenance of a meaningful avifaunistic richness. Migratory birds (n = 183), notably northern ones (n = 43), are among the main players involved in ecological processes of nutrient cycling and dispersion of important pathogens between the two continents. With regard to conservation, 25 species are included in some category of threat in the lists of threatened species with global extinction. We hope that our list will help future researchers a more definitive approach when researching the avian fauna in this bountiful region.

4.
Pap. avulsos Zool. ; 61: e20216182, 2021.
Artigo em Inglês | VETINDEX | ID: vti-32479

Resumo

The Pantanal floodplains of Brazil are a region of rich biodiversity. To date, the true richness of the Pantanal avifauna has not been explored satisfactorily caused by a lack of studies in the region and, especially, by the divergence of opinion among the works published by various authors on the many species found in the region. This is due to the lack of criteria in examining records, both with regard to the reliability of the identifications and in the precise geographical allocation. Therefore, in the study, we collage findings from various studies and records created by us in the last few decades from 199 distinct locations to produce a list of birds in the Pantanal floodplains. We grouped the results into three lists: primary, secondary, and tertiary. We found that the avifauna of the Pantanal floodplain is composed of a total of 617 species, of which 571 (92%) have supporting records of occurrence (primary list) and 46 still lack documentation (secondary list). The number of species listed here for the Pantanal floodplain represents 32% of all avifauna known to the Brazilian territory. This reflects the importance of the biome, as part of the national territory, for the maintenance of a meaningful avifaunistic richness. Migratory birds (n = 183), notably northern ones (n = 43), are among the main players involved in ecological processes of nutrient cycling and dispersion of important pathogens between the two continents. With regard to conservation, 25 species are included in some category of threat in the lists of threatened species with global extinction. We hope that our list will help future researchers a more definitive approach when researching the avian fauna in this bountiful region.(AU)


Assuntos
Animais , Aves/anatomia & histologia , Aves/classificação , Aves/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Biodiversidade , Distribuição Animal
5.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487432

Resumo

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animals presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and trees diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

6.
Pap. avulsos zool ; 61: e20216118, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1287477

Resumo

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animal's presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and tree's diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

7.
Pap. avulsos Zool. ; 61: e20216118, 2021. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765683

Resumo

Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca(Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animals presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and trees diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.(AU)


Assuntos
Animais , Répteis/crescimento & desenvolvimento , Ecossistema , Análise Diferencial Térmica/veterinária , Regulação da Temperatura Corporal/fisiologia
8.
Braz. j. biol ; 81(2): 278-284, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153360

Resumo

The Brasilia Tapaculo, Scytalopus novacapitalis Sick, 1958, is a rare, geographically restricted, and endangered bird species that inhabits riparian vegetation of Cerrado, mainly Gallery Forests. In Serra da Canastra National Park, southeastern Brazil, wetlands are under threat due to frequent non-natural burnings and invasion by feral pigs, Sus scrofa, Linnaeus, 1758. We aimed to evaluate the possible effects of seasonal variations on S. novacapitalis records in undisturbed habitats and answer questions about how fire and feral pigs may affect site occupancy of the species. Transects alongside riparian environments were used to survey n=21 sites, totalizing 7.5 Km, from 2014 to 2019. Results indicated the season influenced both, spontaneous records and induced encounters by playback method, which were more abundant in breeding period, from early spring to summer. The use of playback significantly increased the amount of records in all seasons. The probability of site occupancy in all studied area was higher in late spring (ψ=0.91) and lower in autumn (ψ=0.73). In burned sites (n=8), the first post-fire month showed the lowest probability of occupancy, but there was a rapid recovery in 2nd month and stabilization similar to control area from the 3rd month ahead. After sites (n=11) were invaded by feral pigs, the estimation of site occupancy indicated a slight drop in first two months, but after the 3rd month of invasion the decreasing pattern enhanced the discrepancy with undisturbed areas. It is important to keep monitoring S. novacapitalis population and their threats, to subsidize management actions, especially to avoid frequently unusual burnings in riparian forests, and to block the access of feral pigs to wetlands.


O tapaculo-de-Brasília, Scytalopus novacapitalis, Sick 1958, é uma espécie de ave rara, geograficamente restrita e ameaçada de extinção que habita vegetação ripária do Cerrado, principalmente matas de galeria. No Parque Nacional da Serra da Canastra, sudeste do Brasil, áreas úmidas estão ameaçadas devido a frequentes queimadas não naturais e a invasão por javaporco, Sus scrofa Linnaeus, 1758. Avaliamos os possíveis efeitos da sazonalidade na quantidade de registros de S. novacapitalis em habitats sem perturbação e buscamos responder questões sobre como o fogo e a invasão por javaporco pode afetar a ocupação de área pela ave. Transecções paralelas aos ambientes ripários foram usadas para amostrar n=21 áreas, totalizando 7,5 km, de 2014 a 2019. Os resultados indicaram que a estação do ano influenciou na quantidade de registros espontâneos e de registros induzidos por playback, os quais foram mais abundantes durante o período reprodutivo. O uso de playback aumentou significativamente a quantidade de registros em todas as estações. A probabilidade de ocupação considerando toda área de estudo foi maior no fim da primavera (ψ=0,91) e menor no outono (ψ=0,73). Em áreas queimadas (n=8 trechos), o primeiro mês após o fogo apresentou a menor probabilidade de ocupação, mas houve uma rápida recuperação no 2º mês, e estabilização similar na área controle a partir do 3º mês. Após n=11 trechos terem sido invadidos por javaporcos, a estimativa de ocupação de área indicou pequena queda nos dois primeiros meses, mas a partir do 3º mês, o padrão de decréscimo ampliou a discrepância com áreas não perturbadas. É importante continuar monitorando a população de S. novacapitalis e suas ameaças, para subsidiar ações de manejo, principalmente para evitar queimadas não naturais frequentes nas florestas ripárias e bloquear o acesso de javaporcos às áreas úmidas.


Assuntos
Animais , Sus scrofa , Passeriformes , Parques Recreativos , Brasil , Ecossistema , Incêndios Florestais , Áreas Alagadas , Espécies Introduzidas
9.
Iheringia. Sér. Zool. ; 111: 1-7, 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765909

Resumo

The knowledge of the diversity and distribution of aquatic Oligochaeta (Annelida: Clitellata) species is scarce in southern Brazil. This study presents a list of the species of aquatic Oligochaeta in wetlands and irrigated rice fields in the state of Rio Grande do Sul. Collections were carried out in two large wetland remnants and seven irrigated rice fields distributed in three regions across the state. We recorded eight species from two families (Alluroididae and Naididae). We expanded the distribution ranges of two species (Brinkhurstia americana and Stylaria lacustris), which represent new records for the state of Rio Grande do Sul and registered their occurrence in non-documented environments. In specific, the present study increases to 24 species the aquatic Oligochaeta diversity for the state of Rio Grande do Sul. In addition, the spatial distribution of the species recorded suggests that rice fields support a subset of the wetland fauna of aquatic Oligochaeta. The results provide important information on the ecology and distribution of limnic Oligochaeta and are useful to inform on the diversity of this fauna in agroecosystems.(AU)


O conhecimento sobre a diversidade e distribuição das espécies aquáticas de Oligochaeta (Annelida: Clitellata) é escasso no sul do Brasil. Este estudo apresenta uma lista das espécies de Oligochaeta aquáticas em áreas úmidas e arrozais irrigados no estado do Rio Grande do Sul. As coletas foram realizadas em dois grandes remanescentes de banhados e sete arrozais irrigados distribuídos em três regiões do estado. Nós registramos oito espécies de duas famílias (Alluroididae e Naididae). Nós expandimos as áreas de distribuição de duas espécies (Brinkhurstia americana e Stylaria lacustris), que representam novos registros para o estado do Rio Grande do Sul e documentamos sua ocorrência em diferentes ambientes. Especificamente, o presente estudo aumenta para 24 a diversidade de espécies de Oligochaeta aquáticas para o estado do Rio Grande do Sul. Além disso, a distribuição espacial das espécies registradas sugere que os arrozais sustentam um subconjunto da fauna de Oligochaeta aquática. Os resultados fornecem informações importantes sobre a ecologia e distribuição de Oligochaeta límnicos e são úteis para informar sobre a diversidade desta fauna em agroecossistemas.(AU)


Assuntos
Animais , Oligoquetos/classificação , Oligoquetos/microbiologia , Anelídeos , Demografia , Fauna Aquática
10.
Braz. J. Biol. ; 81(2): 278-284, Mar.-May 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-762724

Resumo

The Brasilia Tapaculo, Scytalopus novacapitalis Sick, 1958, is a rare, geographically restricted, and endangered bird species that inhabits riparian vegetation of Cerrado, mainly Gallery Forests. In Serra da Canastra National Park, southeastern Brazil, wetlands are under threat due to frequent non-natural burnings and invasion by feral pigs, Sus scrofa, Linnaeus, 1758. We aimed to evaluate the possible effects of seasonal variations on S. novacapitalis records in undisturbed habitats and answer questions about how fire and feral pigs may affect site occupancy of the species. Transects alongside riparian environments were used to survey n=21 sites, totalizing 7.5 Km, from 2014 to 2019. Results indicated the season influenced both, spontaneous records and induced encounters by playback method, which were more abundant in breeding period, from early spring to summer. The use of playback significantly increased the amount of records in all seasons. The probability of site occupancy in all studied area was higher in late spring (=0.91) and lower in autumn (=0.73). In burned sites (n=8), the first post-fire month showed the lowest probability of occupancy, but there was a rapid recovery in 2nd month and stabilization similar to control area from the 3rd month ahead. After sites (n=11) were invaded by feral pigs, the estimation of site occupancy indicated a slight drop in first two months, but after the 3rd month of invasion the decreasing pattern enhanced the discrepancy with undisturbed areas. It is important to keep monitoring S. novacapitalis population and their threats, to subsidize management actions, especially to avoid frequently unusual burnings in riparian forests, and to block the access of feral pigs to wetlands.(AU)


O tapaculo-de-Brasília, Scytalopus novacapitalis, Sick 1958, é uma espécie de ave rara, geograficamente restrita e ameaçada de extinção que habita vegetação ripária do Cerrado, principalmente matas de galeria. No Parque Nacional da Serra da Canastra, sudeste do Brasil, áreas úmidas estão ameaçadas devido a frequentes queimadas não naturais e a invasão por javaporco, Sus scrofa Linnaeus, 1758. Avaliamos os possíveis efeitos da sazonalidade na quantidade de registros de S. novacapitalis em habitats sem perturbação e buscamos responder questões sobre como o fogo e a invasão por javaporco pode afetar a ocupação de área pela ave. Transecções paralelas aos ambientes ripários foram usadas para amostrar n=21 áreas, totalizando 7,5 km, de 2014 a 2019. Os resultados indicaram que a estação do ano influenciou na quantidade de registros espontâneos e de registros induzidos por playback, os quais foram mais abundantes durante o período reprodutivo. O uso de playback aumentou significativamente a quantidade de registros em todas as estações. A probabilidade de ocupação considerando toda área de estudo foi maior no fim da primavera (=0,91) e menor no outono (=0,73). Em áreas queimadas (n=8 trechos), o primeiro mês após o fogo apresentou a menor probabilidade de ocupação, mas houve uma rápida recuperação no 2º mês, e estabilização similar na área controle a partir do 3º mês. Após n=11 trechos terem sido invadidos por javaporcos, a estimativa de ocupação de área indicou pequena queda nos dois primeiros meses, mas a partir do 3º mês, o padrão de decréscimo ampliou a discrepância com áreas não perturbadas. É importante continuar monitorando a população de S. novacapitalis e suas ameaças, para subsidiar ações de manejo, principalmente para evitar queimadas não naturais frequentes nas florestas ripárias e bloquear o acesso de javaporcos às áreas úmidas.(AU)


Assuntos
Aves , Espécies em Perigo de Extinção , Sus scrofa , Brasil
11.
Iheringia, Sér. zool ; 111: 1-7, 2021. map, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1483436

Resumo

The knowledge of the diversity and distribution of aquatic Oligochaeta (Annelida: Clitellata) species is scarce in southern Brazil. This study presents a list of the species of aquatic Oligochaeta in wetlands and irrigated rice fields in the state of Rio Grande do Sul. Collections were carried out in two large wetland remnants and seven irrigated rice fields distributed in three regions across the state. We recorded eight species from two families (Alluroididae and Naididae). We expanded the distribution ranges of two species (Brinkhurstia americana and Stylaria lacustris), which represent new records for the state of Rio Grande do Sul and registered their occurrence in non-documented environments. In specific, the present study increases to 24 species the aquatic Oligochaeta diversity for the state of Rio Grande do Sul. In addition, the spatial distribution of the species recorded suggests that rice fields support a subset of the wetland fauna of aquatic Oligochaeta. The results provide important information on the ecology and distribution of limnic Oligochaeta and are useful to inform on the diversity of this fauna in agroecosystems.


O conhecimento sobre a diversidade e distribuição das espécies aquáticas de Oligochaeta (Annelida: Clitellata) é escasso no sul do Brasil. Este estudo apresenta uma lista das espécies de Oligochaeta aquáticas em áreas úmidas e arrozais irrigados no estado do Rio Grande do Sul. As coletas foram realizadas em dois grandes remanescentes de banhados e sete arrozais irrigados distribuídos em três regiões do estado. Nós registramos oito espécies de duas famílias (Alluroididae e Naididae). Nós expandimos as áreas de distribuição de duas espécies (Brinkhurstia americana e Stylaria lacustris), que representam novos registros para o estado do Rio Grande do Sul e documentamos sua ocorrência em diferentes ambientes. Especificamente, o presente estudo aumenta para 24 a diversidade de espécies de Oligochaeta aquáticas para o estado do Rio Grande do Sul. Além disso, a distribuição espacial das espécies registradas sugere que os arrozais sustentam um subconjunto da fauna de Oligochaeta aquática. Os resultados fornecem informações importantes sobre a ecologia e distribuição de Oligochaeta límnicos e são úteis para informar sobre a diversidade desta fauna em agroecossistemas.


Assuntos
Animais , Anelídeos , Demografia , Fauna Aquática , Oligoquetos/classificação , Oligoquetos/microbiologia
12.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1483468

Resumo

ABSTRACT The knowledge of the diversity and distribution of aquatic Oligochaeta (Annelida: Clitellata) species is scarce in southern Brazil. This study presents a list of the species of aquatic Oligochaeta in wetlands and irrigated rice fields in the state of Rio Grande do Sul. Collections were carried out in two large wetland remnants and seven irrigated rice fields distributed in three regions across the state. We recorded eight species from two families (Alluroididae and Naididae). We expanded the distribution ranges of two species (Brinkhurstia americana and Stylaria lacustris), which represent new records for the state of Rio Grande do Sul and registered their occurrence in non-documented environments. In specific, the present study increases to 24 species the aquatic Oligochaeta diversity for the state of Rio Grande do Sul. In addition, the spatial distribution of the species recorded suggests that rice fields support a subset of the wetland fauna of aquatic Oligochaeta. The results provide important information on the ecology and distribution of limnic Oligochaeta and are useful to inform on the diversity of this fauna in agroecosystems.


RESUMO Oligochaeta aquáticos (Annelida: Clitellata) em áreas úmidas e arrozais irrigados no estado do Rio Grande do Sul (Sul do Brasil). O conhecimento sobre a diversidade e distribuição das espécies aquáticas de Oligochaeta (Annelida: Clitellata) é escasso no sul do Brasil. Este estudo apresenta uma lista das espécies de Oligochaeta aquáticas em áreas úmidas e arrozais irrigados no estado do Rio Grande do Sul. As coletas foram realizadas em dois grandes remanescentes de banhados e sete arrozais irrigados distribuídos em três regiões do estado. Nós registramos oito espécies de duas famílias (Alluroididae e Naididae). Nós expandimos as áreas de distribuição de duas espécies (Brinkhurstia americana e Stylaria lacustris), que representam novos registros para o estado do Rio Grande do Sul e documentamos sua ocorrência em diferentes ambientes. Especificamente, o presente estudo aumenta para 24 a diversidade de espécies de Oligochaeta aquáticas para o estado do Rio Grande do Sul. Além disso, a distribuição espacial das espécies registradas sugere que os arrozais sustentam um subconjunto da fauna de Oligochaeta aquática. Os resultados fornecem informações importantes sobre a ecologia e distribuição de Oligochaeta límnicos e são úteis para informar sobre a diversidade desta fauna em agroecossistemas.

13.
Pap. avulsos zool ; 60: e20206011, Feb. 14, 2020. ilus, map
Artigo em Inglês | VETINDEX | ID: biblio-1487226

Resumo

The aim of this paper is to shed light on the boundaries of two sympatric species of Cuernavaca, C. inexacta and C. longula, to enable further ecological studies. Species in this genus are associated with water hyacinths in wetlands of Northeastern Argentina (Paraná-Paraguay waterway system) and the Peruvian Amazon. This work lists new host records for Cuernavaca, which include Pontederia crassipes, P. cordata, P. subovata and P. rotundifolia (Pontederiaceae). A redescription for C. inexacta with new diagnostic genitalic features is also provided, as well as an updated identification key and a distribution map. The genus is distributed throughout Central and South America, reaching north and central Argentina in its southernmost distribution.


Assuntos
Animais , Eichhornia , Hemípteros , Pontederiaceae/parasitologia , Argentina , Áreas Alagadas
14.
Pap. avulsos Zool. ; 60: e20206011, Mar. 16. ilus, mapas
Artigo em Inglês | VETINDEX | ID: vti-25677

Resumo

The aim of this paper is to shed light on the boundaries of two sympatric species of Cuernavaca, C. inexacta and C. longula, to enable further ecological studies. Species in this genus are associated with water hyacinths in wetlands of Northeastern Argentina (Paraná-Paraguay waterway system) and the Peruvian Amazon. This work lists new host records for Cuernavaca, which include Pontederia crassipes, P. cordata, P. subovata and P. rotundifolia (Pontederiaceae). A redescription for C. inexacta with new diagnostic genitalic features is also provided, as well as an updated identification key and a distribution map. The genus is distributed throughout Central and South America, reaching north and central Argentina in its southernmost distribution.(AU)


Assuntos
Animais , Hemípteros , Pontederiaceae/parasitologia , Eichhornia , Áreas Alagadas , Argentina
15.
Acta sci., Biol. sci ; 42: e49894, fev. 2020. map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460921

Resumo

Campos de murundus work as recharge zones and are important for the maintenance of water resources in Brazilian Cerrado. However, with the expansion of the agricultural frontier, this ecosystem may disappear or suffer high anthropogenic disturbances. The aim of the study was to evaluate the structure and distribution of woody species, after the implantation of artificial drainage channels in campo de murundus, in plots near and distant of the drains in the soil. We sampled woody individuals with ≥ 3 cm diameter at the base, and established 20 permanent plots of 20×50 m, 10 of which were between 0-20 m of the drains (edge) and 10 between 150-200 m distant from the drains (interior), totaling two hectares of survey. We recorded 47 species with total density of 230.5 ind.ha-1 and total basal area of 1.331 m2 ha-1. The diversity index of species was H’ = 3.18. We recorded higher density and basal area in the edge, and differential distribution and occupation of woody species in the microrelief of the murundus. This provides us strong evidence that the drains have altered the vegetation structure, especially in the edge of the remnant campos de murundus turning the vegetation woodier and denser.


Assuntos
Biologia do Solo , Drenagem do Solo , Estruturas Vegetais/anatomia & histologia , Estruturas Vegetais/química
16.
Acta sci. vet. (Impr.) ; 48(suppl.1): Pub.507-4 jan. 2020. ilus
Artigo em Português | VETINDEX | ID: biblio-1458334

Resumo

Background: Xanthium spp., the cockleburs, are invasive plants found on riverbanks, lakeshores, and floodplains. Ingestion of Xanthium sprouts or fruit causes cocklebur toxicosis, which is characterized clinically and pathologically by acuteliver failure. The main lesion observed is an accentuation of the lobular pattern of the liver (nutmeg appearance), whichis microscopically characterized by coagulation necrosis in the centrilobular region, hepatocyte degeneration in otherregions of the hepatic parenchyma, and sinusoidal congestion. The objective of this study was to describe an outbreak ofspontaneous cattle poisoning by ingestion of Xanthium spp. sprouts in the southern region of Rio Grande do Sul, Brazil.Case: In September 2018, a beef cattle farm located in Rio Grande county, Rio Grande do Sul, Brazil, reported significantmortality of cattle in a short period of time. There were 700 cattle on the property, divided by class into three differentherds, all kept under extensive conditions in native wetlands. All fields were heavily infested by cocklebur, with mostplants in the budding stage. Twenty animals developed muscle tremors, salivation, aggression, and recumbency. Theclinical course lasted 24 to 48 h, with a lethal outcome in all cases. An 18-month-old male crossbreed bovine was sent tothe Regional Diagnostic Laboratory of the Universidade Federal de Pelotas (UFPel) School of Veterinary Medicine fornecropsy. Gross examination revealed ascites and accentuation of the lobular pattern of the liver. Organ fragments wereharvested and fixed in 10% buffered formalin. Microscopically, the liver exhibited marked coagulation necrosis in thecentrilobular region and vacuolization of the hepatocyte cytoplasm in the midzonal and periportal regions. In the brain,there was perineuronal edema, cytoplasmic shrinkage and basophilia, gliosis, and satellitosis...


Assuntos
Animais , Bovinos , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Hepatopatias/veterinária , Intoxicação por Plantas/veterinária , Xanthium/intoxicação , Magnoliopsida , Plantas Tóxicas , Áreas Alagadas
17.
Acta Sci. Biol. Sci. ; 42: e49894, fev. 2020. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-26754

Resumo

Campos de murundus work as recharge zones and are important for the maintenance of water resources in Brazilian Cerrado. However, with the expansion of the agricultural frontier, this ecosystem may disappear or suffer high anthropogenic disturbances. The aim of the study was to evaluate the structure and distribution of woody species, after the implantation of artificial drainage channels in campo de murundus, in plots near and distant of the drains in the soil. We sampled woody individuals with ≥ 3 cm diameter at the base, and established 20 permanent plots of 20×50 m, 10 of which were between 0-20 m of the drains (edge) and 10 between 150-200 m distant from the drains (interior), totaling two hectares of survey. We recorded 47 species with total density of 230.5 ind.ha-1 and total basal area of 1.331 m2 ha-1. The diversity index of species was H = 3.18. We recorded higher density and basal area in the edge, and differential distribution and occupation of woody species in the microrelief of the murundus. This provides us strong evidence that the drains have altered the vegetation structure, especially in the edge of the remnant campos de murundus turning the vegetation woodier and denser.(AU)


Assuntos
Estruturas Vegetais/anatomia & histologia , Estruturas Vegetais/química , Biologia do Solo , Drenagem do Solo
18.
Acta sci. vet. (Online) ; 48(suppl.1): Pub. 507, 5 jun. 2020. ilus
Artigo em Português | VETINDEX | ID: vti-31759

Resumo

Background: Xanthium spp., the cockleburs, are invasive plants found on riverbanks, lakeshores, and floodplains. Ingestion of Xanthium sprouts or fruit causes cocklebur toxicosis, which is characterized clinically and pathologically by acuteliver failure. The main lesion observed is an accentuation of the lobular pattern of the liver (nutmeg appearance), whichis microscopically characterized by coagulation necrosis in the centrilobular region, hepatocyte degeneration in otherregions of the hepatic parenchyma, and sinusoidal congestion. The objective of this study was to describe an outbreak ofspontaneous cattle poisoning by ingestion of Xanthium spp. sprouts in the southern region of Rio Grande do Sul, Brazil.Case: In September 2018, a beef cattle farm located in Rio Grande county, Rio Grande do Sul, Brazil, reported significantmortality of cattle in a short period of time. There were 700 cattle on the property, divided by class into three differentherds, all kept under extensive conditions in native wetlands. All fields were heavily infested by cocklebur, with mostplants in the budding stage. Twenty animals developed muscle tremors, salivation, aggression, and recumbency. Theclinical course lasted 24 to 48 h, with a lethal outcome in all cases. An 18-month-old male crossbreed bovine was sent tothe Regional Diagnostic Laboratory of the Universidade Federal de Pelotas (UFPel) School of Veterinary Medicine fornecropsy. Gross examination revealed ascites and accentuation of the lobular pattern of the liver. Organ fragments wereharvested and fixed in 10% buffered formalin. Microscopically, the liver exhibited marked coagulation necrosis in thecentrilobular region and vacuolization of the hepatocyte cytoplasm in the midzonal and periportal regions. In the brain,there was perineuronal edema, cytoplasmic shrinkage and basophilia, gliosis, and satellitosis...(AU)


Assuntos
Animais , Bovinos , Xanthium/intoxicação , Intoxicação por Plantas/veterinária , Hepatopatias/veterinária , Doença Hepática Induzida por Substâncias e Drogas/veterinária , Plantas Tóxicas , Magnoliopsida , Áreas Alagadas
19.
Artigo em Inglês | VETINDEX | ID: vti-745549

Resumo

Abstract The Brasilia Tapaculo, Scytalopus novacapitalis Sick, 1958, is a rare, geographically restricted, and endangered bird species that inhabits riparian vegetation of Cerrado, mainly Gallery Forests. In Serra da Canastra National Park, southeastern Brazil, wetlands are under threat due to frequent non-natural burnings and invasion by feral pigs, Sus scrofa, Linnaeus, 1758. We aimed to evaluate the possible effects of seasonal variations on S. novacapitalis records in undisturbed habitats and answer questions about how fire and feral pigs may affect site occupancy of the species. Transects alongside riparian environments were used to survey n=21 sites, totalizing 7.5 Km, from 2014 to 2019. Results indicated the season influenced both, spontaneous records and induced encounters by playback method, which were more abundant in breeding period, from early spring to summer. The use of playback significantly increased the amount of records in all seasons. The probability of site occupancy in all studied area was higher in late spring (=0.91) and lower in autumn (=0.73). In burned sites (n=8), the first post-fire month showed the lowest probability of occupancy, but there was a rapid recovery in 2nd month and stabilization similar to control area from the 3rd month ahead. After sites (n=11) were invaded by feral pigs, the estimation of site occupancy indicated a slight drop in first two months, but after the 3rd month of invasion the decreasing pattern enhanced the discrepancy with undisturbed areas. It is important to keep monitoring S. novacapitalis population and their threats, to subsidize management actions, especially to avoid frequently unusual burnings in riparian forests, and to block the access of feral pigs to wetlands.


Resumo O tapaculo-de-Brasília, Scytalopus novacapitalis, Sick 1958, é uma espécie de ave rara, geograficamente restrita e ameaçada de extinção que habita vegetação ripária do Cerrado, principalmente matas de galeria. No Parque Nacional da Serra da Canastra, sudeste do Brasil, áreas úmidas estão ameaçadas devido a frequentes queimadas não naturais e a invasão por javaporco, Sus scrofa Linnaeus, 1758. Avaliamos os possíveis efeitos da sazonalidade na quantidade de registros de S. novacapitalis em habitats sem perturbação e buscamos responder questões sobre como o fogo e a invasão por javaporco pode afetar a ocupação de área pela ave. Transecções paralelas aos ambientes ripários foram usadas para amostrar n=21 áreas, totalizando 7,5 km, de 2014 a 2019. Os resultados indicaram que a estação do ano influenciou na quantidade de registros espontâneos e de registros induzidos por playback, os quais foram mais abundantes durante o período reprodutivo. O uso de playback aumentou significativamente a quantidade de registros em todas as estações. A probabilidade de ocupação considerando toda área de estudo foi maior no fim da primavera (=0,91) e menor no outono (=0,73). Em áreas queimadas (n=8 trechos), o primeiro mês após o fogo apresentou a menor probabilidade de ocupação, mas houve uma rápida recuperação no 2º mês, e estabilização similar na área controle a partir do 3º mês. Após n=11 trechos terem sido invadidos por javaporcos, a estimativa de ocupação de área indicou pequena queda nos dois primeiros meses, mas a partir do 3º mês, o padrão de decréscimo ampliou a discrepância com áreas não perturbadas. É importante continuar monitorando a população de S. novacapitalis e suas ameaças, para subsidiar ações de manejo, principalmente para evitar queimadas não naturais frequentes nas florestas ripárias e bloquear o acesso de javaporcos às áreas úmidas.

20.
Zoologia (Curitiba, Impr.) ; 36: e30475, Apr. 18, 2019. map, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1504551

Resumo

The Amazon floodplains become periodically submerged as result of seasonal changes in the water levels throughout the year. These changes influence the availability of microhabitats and consequently the abundance of organisms in these ecosystems. In this study we investigated 1) how changes in the water level affect the richness and abundance of ardeid birds in the lowland floodplain lakes of the lower Amazon River, and 2) the microhabitats used by these birds throughout the seasonal cycle. Ten lakes were surveyed at each of the four phases of the seasonal cycle. In total, 3,280 individuals of 11 species were recorded. Of these, eight species occurred in the four phases, and three were observed in one or two phases. In the analysis including the entire family, there were more individuals in the phase with waters at lowest level and less in the phase that the water level was lowering. Many species were present throughout the seasonal cycle, suggesting that they might be resident species. However, their abundance varied throughut the cycle, suggesting that parts of their populations temporarily migrate elsewhere. The microhabitat that was most commonly used by most species at all phases of the seasonal cycle, with the excetions noted below, was aquatic macrophytes, suggesting that ardeid birds have a strong preperence for this kind of habitat. Three species - Egretta caerulea (Linnaeus, 1758), Nycticorax nycticorax (Linnaeus, 1758) and Bubulcus ibis (Linnaeus, 1758) - preferred other microhabitats at some phase of their seasonal cycle. The present study shows that the floodplain lakes of the lower Amazon River are richer in ardeid bird species than other areas of the Amazon biome and other biomes in Brazil. The fact that we found rare species in our study and that they depend on aquatic macrophytes demonstrates the importance of conserving the floodplain lakes of the lower Amazon River.


Assuntos
Animais , Aves , Estação Chuvosa , Estação Seca , Macrófitas , Medição de Níveis de Água , Biota , Brasil , Ecossistema Amazônico/análise , Áreas Alagadas
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