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1.
Neotrop. ichthyol ; 19(1): e200071, 2021. tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1287435

RESUMO

Dams often cause drastic changes in freshwater environments and can compromise the quality and availability of food resources in rivers. This study aims to analyze the influence of a dam on the trophic structure of fish assemblages in lotic areas located both upstream and downstream of the Irapé Hydroelectric Power Plant. Fish sampling occurred before (2003 to 2005) and after (2011 to 2017) the impoundment, which began in 2006. The trophic structure and species composition before dam construction were similar upstream of the reservoir and downstream of the dam. After the building of the dam, both aspects of the assemblages changed along the lotic stretches - the upstream incurred an increase in biomass of detritivores and a decrease of piscivores and omnivores, while downstream went exactly the opposite, causing a differentiation between the two assemblages. Because lotic areas upstream of reservoirs are also impacted by river damming, efforts for impact mitigation should also focus on these areas.(AU)


Barragens causam mudanças drásticas em ambientes de água doce e podem comprometer a qualidade e a disponibilidade de recursos alimentares nos rios. Este estudo teve como objetivo analisar a influência de uma barragem na estrutura trófica da assembleia de peixes em áreas lóticas localizadas a montante e a jusante da usina hidrelétrica de Irapé. A amostragem de peixes ocorreu antes (2003 a 2005) e após (2011 a 2017) o fechamento das comportas, iniciado em 2006. A estrutura trófica e a composição das espécies antes da construção da barragem eram semelhantes a montante do reservatório e a jusante da barragem. Após a construção da barragem, ambos os aspectos das assembleias mudaram ao longo dos trechos lóticos - a montante ocorreu um aumento na biomassa de detritívoros e diminuição de piscívoros e onívoros, enquanto a jusante ocorreu exatamente o oposto, causando uma diferenciação entre as duas assembleias. Como as áreas lóticas a montante dos reservatórios também são impactadas por barramentos, esforços para mitigação de impactos também devem se concentrar nessas áreas.(AU)


Assuntos
Animais , Barragens , Reservatórios de Água , Energia Hidrelétrica/análise , Níveis Tróficos , Peixes
2.
Acta sci., Biol. sci ; 43: e52230, 2021. map, tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1461022

RESUMO

Coastal habitats have great ecological importance with estuarine environments providing feeding sites for many fish species, especially during juvenile life stages. This study investigates the diet composition and trophic guild organization of the common and abundant ichthyofauna in shallow areas of the Todos os Santos Bay (TSB), Bahia, Brazil, and their relationships with environmental parameters. Six fish sampling campaigns were carried out in the shallow zones (infralittoral) of the Paraguaçu River estuary which encompasses the inner and outer (marine exposure) reaches of theTSB. The stomach contents of 1231 individualsbelonging to common and abundant species were examined. A total of 32 food items were identifiedand fish were into four trophic guilds: detritivores, zoobenthivores I, zoobenthivores II, and zooplanktivores. The relationship between the guilds and environmental parameters showed that zoobenthivores II and zooplanktivores guilds had a positive relationship with salinity and pH, explaining 86% of data variability, though only the salinity variable was significant. This study provides basic information about the diet composition of common and abundant species in the TSBand their organization into trophic guilds. In addition, demonstrates that shallow waters fish across all guilds have broadly similar diets, comprising food items that are usually associated with bottom waters.


Assuntos
Animais , Dieta , Ecossistema , Peixes/metabolismo
3.
J Environ Biol ; 2020 Jul; 41(4): 745-754
Artigo | IMSEAR | ID: sea-214538

RESUMO

Aim: The present study was aimed to analyze the ecological significance of Ulhas River estuary of the western coast of India using the taxonomic, functional and conservation aspects, and also to record an updated data base on the estuarine community structure.Methodology: Ichthyo faunal diversity was assessed by experimental fishing conducted at 3 selected stations using single day dolnets of code end mesh size of 10mm, from September 2017 to August 2018. The diversity of fish species was recorded considering the most relevant taxonomic classification data and further supplemented by the information pertaining to ecological roles played by the individual species (using guild approach) and the IUCN- conservation status. Results: There were 105 species, belonging to 4 classes, 19 orders, 44 families and 75 genera, recorded from Ulhas River Estuary. The class: Actinopterygii was the most diverse taxa, (including 12 orders, 32 families and 55 genera) among the total ichthyofauna reported. Order Perciformes was the most representative order of the class (40 species, 31 genera and 17 families), followed by Decapoda (21species, 8 genera and 6 families). Based on the estuarine usefunctional guild categorization, 51.42 % of the species were marine migrants, followed by amphidromous species (21.9%). Zoobenthivores (29.41%) was found to be the most dominant feeding guild followed by omnivores (19.6%). Based on the IUCN Red List, 53.33% of the fish species observed from Ulhas River Estuary were categorized as “Not Evaluated”, and 7% were “Data Deficient”, signifying the lack of information on biological aspects of the species along Indian waters. Tenualosa toli marked its presence under threatened category (Vulnerable) from Ulhas River Estuary. Interpretation: The abundance of marine migrants as well as the amphidromous species in the estuary signifies the use of this ecosystem for the nursery function of commercially important marine fisheries resources. Increased proportion of “Not Evaluated” and “Data Deficient” categories in the context of high level of anthropogenic stress demands for more updated documentation of the biodiversity and periodic changes in its ecological structure for formulating and implementing effective ecosystem-based management programs for such sensitive estuarine ecosystems.

4.
Rev. biol. trop ; 68(1)mar. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507649

RESUMO

Las áreas que se recuperan perturbaciones tales como actividades agrícolas y ganaderas, generan un aumento de bosques secundarios que causan cambios en la cantidad y calidad del hábitat disponible para las aves. El Índice de Integridad Biótica (IIB) compara la estructura, composición y función del ensamblaje de las aves en una regeneración secundaria del bosque, desde edades tempranas hasta maduras, para evaluar su condición ecológica. Se estudió la integridad ecológica utilizando el IIB en cuatro etapas de sucesión de bosque secundario. El IBI se calculóutilizando ensamblajes de aves encontrados en estas cuatro etapas de la sucesión de bosques, y su desempeño se comparócon la riqueza general y elíndice de diversidad de Shannon. Se realizaron cinco muestreos de campo entre junio 2016 y febrero 2017, en los que se registraron las aves utilizando recuentos de puntos de radio fijo. En total, se registraron 9 516 individuos de 187 especies de aves pertenecientes a 42 familias y 15 órdenes. Para cada especie se estableció hábitat de presencia, gremio de forrajeo y grupos de indicadores potenciales. La riqueza de especies y el Índice de Abundancia Puntual (PAI) de todas las categorías, se utilizaron como métricas candidatas y luego de evaluar un total de 34 métricas, se seleccionaron 13 para los análisis. Las métricas que se correlacionaron positivamente con el gradiente, de mayor a menor perturbación, fueron: riqueza de insectívoros de interior de bosque, abundancia de especies exclusivamente de interior de bosque, abundancia de especies de interior y borde, abundancia de especies endémicas y abundancia de especies amenazadas. Las métricas que se correlacionaron negativamente con el gradiente, de mayor a menor perturbación, fueron abundancia de especies de áreas abiertas, abundancia de especies de áreas abiertas y de borde, abundancia de frugívoros, abundancia de granívoros, abundancia de omnívoros, abundancia de insectívoros, abundancia de carroñeros y abundancia de especies migratorias. El IBI mostró una correlación lineal significativa positiva con el gradiente de regeneración secundaria del bosque, desde edades tempranas hasta maduras, mientras que la riqueza total de especies y el índice de diversidad de Shannon mostraron una correlación lineal negativa. El IBI, en este caso particular, demostró ser mejor que las medidas clásicas de la riqueza de especies y el índice de diversidad de Shannon para evaluar e interpretar la condición ecológica y ambiental de las etapas de la sucesión del bosque secundario evaluado.


Recovering areas from disturbance, after agriculture and livestock activities, increases secondary forests extension, which might change the quantity and quality of available habitat for birds. The Index of Biotic Integrity (IBI) compare the structure, composition and function of bird assemblages in secondary regeneration forest, from early succession to mature forest, to evaluate the ecological condition. Thus, the ecological condition along four stages of secondary forest in Antioquia, Colombia were studied using the IBI. This index was compared with richness and Shannon's diversity Index of the same bird assemblages. Five field surveys were conducted between June 2016 and February 2017, using fixed-radius point counts. In total 9 516 individuals, from 187 bird species, belonging to 42 families and 15 orders were recorded. Habitat of occurrence, foraging guild and potential indicators groups were established for every species. Species richness and Punctual Abundance Index (PAI) of all categories were defined as candidate metrics, and after evaluating a total of 34 metrics, 13 were selected for further analysis. Metrics that were positively correlated with successional forest gradient, from highest to lowest disturbance, were: species richness of forest interior insectivorous, abundance of exclusively forest species, abundance of forest interior and edge species, abundance of endemic species and abundance of threatened species. Metrics that were negatively correlated with successional forest gradient, from highest to lowest disturbance, were: abundance of species from open areas, abundance of open areas and edge species, abundance of frugivorous, abundance of granivorous, abundance of omnivorous, abundance of insectivorous, abundance of scavengers and abundance of migratory species. IBI showed a positive significant linear correlation with the gradient of secondary forest regeneration, from early to mature forest, while Shannon´s diversity Index and species richness showed a negative significant linear correlation. So that, in this particular case, IBI proved to be better indicator that the classical measures for assessing and interpreting ecological and environmental condition along the secondary forest succession evaluated.

5.
Acta biol. colomb ; 24(2): 224-231, May-ago. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1010852

RESUMO

RESUMEN Se analiza el origen y evolución del término gremio, así como su aplicación en ecología, considerando las múltiples connotaciones que se le ha dado y la confusión que se ha generado por utilizarlo de forma indebida. De igual forma, se discute la importancia de homogenizar los términos y definir de manera clara a los gremios, a fin de tener un leguaje que permita entender los alcances del término sin ambigüedades. El uso del término, así como su persistencia en estudios ecológicos, sugiere que el mismo tiene relevancia considerable dependiendo de la forma y el modo en que es empleado. El uso inadecuado o derivado de este término es arriesgado y peligroso, dado que tiende a reducir el término a una palabra vacía con múltiples significados. Más que nada, esta trivialización constituye una amenaza al uso y significado adecuado del concepto de gremio en ecología.


ABSTRACT The origin and evolution of the term guild are analyzed, as well as its application in ecology, considering the multiple connotations that have been given and the confusion that has been generated by using it improperly. Likewise, the importance of homogenizing the terms and clearly defining the guilds is discussed, to have a language that allows understanding the scope of the term without ambiguities. The use of the term, as well as its persistence in ecological studies, suggests that it has considerable relevance depending on the form and the way it is used. The inappropriate or derivative use of this term is risky and dangerous since it tends to reduce the term to an empty word with multiple meanings. Also, this trivialization constitutes a threat to the proper use of the guild concept in ecology and its meaning as a whole.

6.
Artigo | IMSEAR | ID: sea-204813

RESUMO

The internal organization of reef-fish communities, particularly the species richness and the hierarchical structuring of species abundances, depends on many environmental factors, including fishing intensity and proportion of macroalgal cover which are expected to have determinant influences. However, reported studies on this topic are generally based on incomplete samplings (almost unavoidable in practice when dealing with highly uneven and species-rich communities), so that the derived results can be appreciably skewed. To overcome this difficulty, the incomplete samplings involved in this study were completed numerically through a reliable extrapolation procedure. This precaution provided a safe confirmation that reduced fishing activity and increased macroalgae cover both contribute to enhance the total species richness and to reduce the abundance unevenness in these reef fish communities. Yet, it is shown that this reduction of abundance unevenness is almost entirely attributable to the increase in species richness.

7.
Mycobiology ; : 13-23, 2018.
Artigo em Inglês | WPRIM | ID: wpr-730005

RESUMO

Depending on the mode of nutrition exploitation, major fungal guilds are distinguished as ectomycorrhizal and saprotrophic fungi. It is generally known that diverse environmental factors influence fungal communities; however, it is unclear how fungal communities respond differently to environment factors depend on fungal guilds. In this study, we investigated basidiomycetes communities associated with Quercus mongolica using 454 pyrosequencing. We attempted to detect guild pattern (ectomycorrhizal or saprotrophic fungal communities) by comparing the influence of geography and source (root and surrounding soil). A total of 515 mOTUs were detected from root (321) and soil (394) of Q. mongolica at three sites of Mt. Jeombong in Inje County. We found that patterns of diversity and community structure were different depending on the guilds. In terms of alpha diversity, only ectomycorrhizal fungi showed significant differences between sources. In terms of community structure, however, geography significantly influenced the ectomycorrhizal community, while source appeared to have a greater influence on the saprotrophic community. Therefore, a guild-based view will help to elucidates novel features of the relationship between environmental factors and fungal communities.


Assuntos
Basidiomycota , Fungos , Geografia , Quercus , República da Coreia , Solo
8.
Rev. biol. trop ; 65(4): 1540-1553, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-897641

RESUMO

Abstract Neotropical wetlands comprise contrasting habitats with highly diverse avifauna, including herbivores, insectivores and carnivores, of both terrestrial and aquatic species. Therefore, comparisons between wetland bird assemblages based only on species identity may disregard turnover within ecological groups, and eclipse important variations between habitat types. We studied bird assemblages from mangrove and estuary habitat types from a coastal lagoon system in Oaxaca, Mexico. For this, we used 640 point counts to obtain data on bird species using those habitats between October 2009 and May 2012. We ascertained guild structure by classifying 139 species in a scalar hierarchy of two-levels: 17 key-resource guilds nested within seven trophic guilds. To evaluate variation in guild structure between habitat types, we contrasted richness and diversity across trophic guilds and tested for variation in abundance within key-resource guilds. We exposed a tendency of greater diversity within terrestrial guilds in mangrove and within aquatic guilds at the estuary. However, these differences were compensatory and neither richness nor diversity varied between habitat types in comparisons across the sets of trophic guilds. Parallel analyses at two hierarchical levels supported the theoretical prediction of greater change at lower levels. Herpetofauna, wood invertebrates, aquatic invertebrates and seeds emerged as dietary components that may explain the distribution of abundance in key-resource guilds. Although the guilds from mangrove and estuary produced comparable sets of richness and diversity values, the actual identity of guilds with high values varied between habitats. On the other hand, species abundance comparisons within guilds pinpointed specific associations with habitat types and this method represents a suitable strategy for identifying habitat preferences in complex wetland bird assemblages.


Resumen Los humedales neotropicales comprenden hábitats contrastantes con avifaunas altamente diversas que incluyen especies terrestres y acuáticas de herbívoros, insectívoros y carnívoros. Por lo cual, las comparaciones entre los ensambles avifaunísticos de los humedales basados únicamente en la identidad de especies podrían ignorar el recambio entre grupos ecológicos, y ocultar variaciones importantes entre tipos de hábitat. Nosotros estudiamos ensambles avifaunísticos de tipos de hábitat de manglar y estuario en un sistema lagunar de la costa de Oaxaca, México. Entre octubre 2009 y mayo 2012, utilizamos 640 puntos de conteo para determinar la estructura de gremios mediante la clasificación de 139 especies en una jerarquía escalar de dos niveles: 17 gremios de recursos claves anidados en siete gremios tróficos. Para evaluar la variación en la estructura jerárquica entre tipos de hábitat, contrastamos la riqueza y diversidad a través de gremios tróficos y probamos para variación en la abundancia dentro de gremios de recursos claves. Registramos una tendencia de mayor diversidad en gremios terrestres del manglar y en gremios acuáticos del estuario. Sin embargo, ésta variación fue compensatoria, ya que ni la riqueza específica ni la diversidad variaron entre los tipos de hábitat a través de los conjuntos de gremios tróficos. Un análisis paralelo de dos niveles jerárquicos soportó la predicción de un mayor recambio en niveles inferiores. La herpetofauna, los invertebrados en madera, los invertebrados acuáticos, y las semillas se presentaron como componentes alimenticios que podrían explicar la distribución de abundancia en los gremios de recursos claves. Aunque los gremios del manglar y estuario produjeron conjuntos comparables de valores de riqueza y diversidad, la identidad exacta de los gremios con valores altos variaba entre hábitats. Por otro lado, las comparaciones de abundancia dentro los gremios determinaron asociaciones específicas con tipos de hábitat y este método representa una estrategia apta para identificar las preferencias de hábitat en ensambles complejos de aves en humedales.

9.
Rev. biol. trop ; 65(3): 917-924, Jul.-Sep. 2017. ilus
Artigo em Inglês | LILACS | ID: biblio-897592

RESUMO

AbstractDung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are considered essential for enhancing the physicochemical characteristics of soils, principally by changing organic materials (e.g. dead animals, faeces, fruits e leaf litter). This study compared the species richness and abundance of dung beetles captured using various types of baits, to demonstrate attractiveness differences in variable habitats of the Brazilian Amazon. Samplings were carried out with pitfall traps baited with human faeces, rotten banana, rotten meat and a nonbaited trap, in February, March, June, September and October 2015. Habitats included native forests, agriculture areas, pastures and disturbed forests in different regeneration stages. A total of 13 736 Scarabaeinae beetles were captured, distributed over 98 species. Most individuals were captured using traps baited with faeces (76.7 % of individuals), followed by rotten meat baited traps (17.8 % of individuals), fermented banana baited traps (3.9 % of individuals) and finally by non-baited traps (1.6 % of individuals). A significant difference in attractiveness of the different baits used and habitats types was observed. Most of the captured assemblages were composed by coprophagous (42 %), generalist species (32 %), necrophagous (15 %) and none was classified as saprophagous. Approximately 54 % of the specimens were tunnelers, 25 % were rollers and 12 % were dwellers. The species of Scarabaeinae sampled in the region revealed qualitative and quantitative differences among their assemblages and the phytophysiognomies. The forest environments housed the greatest species richness observed, and a fraction of these is exclusive of those areas. We concluded that some species of Scarabaeinae have an important potential as disturbance indicators in the Amazonian ecosystem. Rev. Biol. Trop. 65 (3): 917-924. Epub 2017 September 01.


ResumenLos escarabajos peloteros (Coleoptera: Scarabaeidae: Scarabaeinae) son considerados fundamentales para la mejora de las características físico-químicas de los suelos, es decir, para la descomposición de materiales orgánicos (p. ej., animales muertos, heces, frutas y hojarasca). Este estudio compara la riqueza de especies y la abundancia de escarabajos peloteros, capturados utilizando diversos tipos de cebos, para demostrar diferencias en la atracción en hábitats de la Amazonía Brasileña. Se realizaron muestreos con trampas cebadas con heces humanas, plátano podrido, carne podrida y una trampa sin cebo. Los hábitats incluyen bosques nativos, zonas de agricultura, pastos y bosques alterados en diferentes fases de regeneración. Se capturaron un total de 13 736 escarabajos Scarabaeinae, distribuidos en 98 especies. La mayoría de los individuos fueron capturados en trampas cebadas con heces (76.7 % de los individos), seguido por las trampas con cebo de carne podrida (17.8 % de los individuos), trampas con cebo de plátano fermentado (3.9 % de los individuos) y finalmente por las trampas sin cebo (1.6 % de los individuos). Se observó una diferencia significativa en la atracción de los diferentes cebos y hábitats. La mayoría de la comunidad capturada estuvo compuesta de escarabajos coprófagos (42 %), especies generalistas (32 %) y necrófagos (15 %) y ninguno fue clasificado como saprófago. Aproximadamente, el 54 % de las muestras fueron excavadores, 25 % rodadores y 12 % residentes. Las especies de scarabaeinae muestreadas en la región revelaron diferencias cualitativas y cuantitativas entre sus ensamblajes y las fitofisionomías muestreadas. Los ambientes forestales albergaron la mayor riqueza de especies observada y una fracción de ellas es exclusiva de este entorno. Concluimos que algunas especies de Scarabaeinae tienen un potencial importante como indicadores de alteración en el ecosistema amazónico.

10.
Rev. biol. trop ; 64(1): 289-303, ene.-mar. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-843278

RESUMO

ResumenLos escarabajos pasálidos son componentes importantes de los bosques tropicales debido a que facilitan el reciclaje de nutrientes propios de madera en descomposición, ya sea por acción directa (consumo) o indirecta (facilitando la acción de otros organismos). En la actualidad los estudios ecológicos dentro del grupo son escasos y se han centrado en respuestas a cambios ambientales relacionados con su recurso alimenticio. En el presente estudio se caracterizó la composición gremial de escarabajos pasálidos, distribuida en un gradiente altitudinal, de acuerdo a sus características de aprovechamiento del recurso. Se cuantificaron aspectos morfoecológicos de importancia adaptativa para la explotación diferencial del recurso (medidas corporales, puntos homólogos en cuerpo y alas y series de Fourier en protibias). Se reconocieron cinco especies, 198 grupos familiares y tres gremios: el subcortícola, el alboduramícola y el generalista. La riqueza de la comunidad disminuyó conforme aumentó la altitud. Los cambios entre las variables morfométricas lineales se vieron influenciadas por la altitud; por su parte, los datos morfogeométricos se comportaron independientes del gradiente. El análisis de marcadores morfológicos (morfogeométrico) arrojó información relevante para la delimitación de los gremios ya establecidos en esta familia. Dentro de estos, la forma general del cuerpo junto a las tibias anteriores, aportaron la mayor información de agrupación gremial. La cuantificación de dichos marcadores evidenció la relación entre los tipos de aprovechamiento del recurso, ya que al ser estructuras importantes en el movimiento y consumo de la madera en microzonas particulares, permite plantear roles funcionales puntuales. Reconocer estas variables en interacción con aquellas ecológicas brinda herramientas para el entendimiento de la riqueza y los aportes funcionales de los escarabajos pasálidos al ecosistema.


AbstractBess beetles are important components on tropical forest dead wood nutrient cycling, since they act as direct consumers and ease the consumption by another organism (indirect). Studies of bess beetle ecology are scarce and have focused on communities responses to environmental changes on alimentary resources. We characterized the bess beetles guild composition in an elevation gradient, according to their differential use of resources (microhabitat) and morphological traits quantification (geometric and lineal), as a potential tool to improve our understanding on resource use and functional ecology of beetles. Three guilds (underbark, sapwood-heartwood and generalists feeders), five species and 198 familiar groups were recognized; their richness decreased as elevation increased. Changes in linear morphometric measures were influenced by elevation; morphogeometrical measures were not associated with the elevation gradient, only grouping at guild level were observed. Morphological markers analysis (morphometric) provided information to guild delimitation. Body and metatibiae shape contributed with the best information to guild grouping. Quantification of those structural markers proved the relationship between resource repartition, because they are involved in movement on wood galleries and wood consumption, this fact allowed to propose specific functional roles. The identified patterns have contributed on the understanding of functional processes in Passalidae communities and their role in ecosystem function.


Assuntos
Animais , Besouros/anatomia & histologia , Clima Tropical , Besouros/classificação , Besouros/fisiologia , Florestas , Colômbia , Biodiversidade
11.
Rev. biol. trop ; 62(supl.2): 169-178, abr. 2014. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-753764

RESUMO

Feeding habits of immature individuals of Ephemeroptera, Plecoptera, and Trichoptera from middle reaches of a tropical mountain stream. Morphological and behavioral aspects of insects allow their grouping in trophic guilds and represent their dependence on food resources. We determined the feeding habits of immature organisms of Ephemeroptera, Plecoptera, and Trichoptera (EPT) from the middle reaches of Gaira stream (Sierra Nevada de Santa Marta, Colombia), using gut content analysis. We identified 13 EPT genera, but only ten were analyzed for a total of 100 organisms. We describe six food items: animal parts (AP), vascular plant tissue (VPT), microalgae (M), fungi (F), coarse particulate organic matter (CPOM) and fine particulate organic matter (FPOM). Baetodes was determined to be a collector-scraper, since FPOM represented 46.6% of food content, followed by F (38.4%). Chimarra, Leptohyphes, Lachlania, and Thraulodes were categorized as collectors with average proportions of FPOM 86.8%, 93.1%, 93.1% and 93.7%, respectively. Phylloicus, Smicridea and Leptonema were main consumers of VPT and CPOM with proportions of 76.3%, 54.6%, and 62.4%, respectively; while ratios of FPOM were 22.3%, 38.8%, and 32.9%, respectively. While all are detritivores, Phylloicus is functionally classified as shredders and Smicridea and Leptonema as collectors. Atopsyche and Anacroneuria were the only taxa in which AP were observed in high proportions, 57.9% and 58.2%, respectively, for that reason they were classified as predators. The organisms examined consume a wide variability of resources. Rev. Biol. Trop. 62 (Suppl. 2): 169-178. Epub 2014 April 01.


Los aspectos morfológicos y de comportamiento de insectos permiten agruparlos en gremios, y representar la dependencia de la comunidad lotica hacia recursos alimentarios particulares. Se evaluó los hábitos alimentarios de organismos inmaduros de Ephemeroptera, Plecoptera y Trichoptera (EPT) de la parte media del río Gaira (Sierra Nevada de Santa Marta, Colombia), por medio del análisis del contenido estomacal. Se identificaron 13 géneros de EPT, pero solo a diez de éstos se les revisó el contenido estomacal, para un total de 100 organismos analizados. Se describieron seis ítems alimentarios: restos animales (RA), tejido de plantas vasculares (TPV), Microalgas (MA), hongos (HN), materia orgánica particulada gruesa (MOPG) y materia orgánica particulada fina (MOPF). Baetodes se registró como Recolector-Raspador, ya que su principal ítem alimentario fue MOPF (46.6%) seguido de HN (38.4%). Chimarra, Leptohyphes, Thraulodes y Lachlania, se categorizaron como Recolectores con proporciones promedio de 86.8%, 93.1%, 93.1% y 93.7% de MOPF, respectivamente. En los géneros Phylloicus, Leptonema y Smicridea se observó principalmente TPV y MOPG con 76.3%, 54,6% y 62.4% junto con proporciones de MOPF de 22.3%, 38.8% y 32.9%, respectivamente. Categorizado como Detritívoro, Phylloicus es funcionalmente clasificado como Fragmentador y Leptonema y Smicridea como Recolectores. Los géneros Anacroneuria y Atopsyche fueron clasificados como Depredadores y fueron los únicos taxones en los que se observó RA en altas proporciones (57.9% y 58.2%). Nuestro estudio sugiere que los organismos examinados ingieren una amplia variabilidad de recursos.


Assuntos
Animais , Monitoramento Ambiental , Comportamento Alimentar/fisiologia , Insetos/classificação , Insetos/fisiologia , Colômbia , Rios
12.
Rev. bras. entomol ; 57(1): 47-54, jan.-mar. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-669493

RESUMO

Dung beetle assemblages (Coleoptera, Scarabaeinae) in Atlantic forest fragments in southern Brazil. The beetles of the subfamily Scarabaeinae are important organisms that participate in the cycle of decomposition, especially in tropical ecosystems. Most species feed on feces (dung) or carcasses (carrion) and are associated with animals that produce their food resources. Dung beetles are divided into three functional groups: rollers, tunnelers and dwellers. This present work aims to study the diversity of dung beetle communities inhabiting fragments of the Atlantic Forest, with the purpose of describing the ecology of the species in southern Brazil. This study was conducted in the region of Campos Novos, in Santa Catarina, where twenty sites of Atlantic forest fragments were sampled. Samplings of dung beetles were conducted using 200 pitfall traps, of which 100 were baited with human feces and another 100 with carrion. Size and environmental complexity were also measured for each forest fragment. A total of 1,502 dung beetles, belonging to six tribes, 12 genera and 33 species, were collected. Results of the Levin's index of niche breadth indicated that 11 species were categorized as being coprophagous, ten as generalists, and two as necrophagous. Most species are tunnelers (19), nine of rollers and four of dwellers. The great diversity of Scarabaeinae in the region of Campos Novos, including several rare species, adds important data to the Scarabaeinae fauna in the central-western region of Santa Catarina. It may also help choosing priority areas for conservation in the region, where human impact, with large areas of monoculture, increasingly threatens the fragments of Mixed Ombrophilous Forest.

13.
Neotrop. ichthyol ; 11(4): 871-880, 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-697855

RESUMO

We determined in this study the habitat preferences of seven native fish species in a regulated river in Southeastern Brazil. We tested the hypothesis that fishes differ in habitat preference and that they use stretches of the river differing in hydraulic characteristics and substrate type. We surveyed fishes in four 1-km long river stretches encompassing different habitat traits, where we also measured water depth, velocity, and substrate type. We investigated preference patterns of four Siluriformes (Loricariichthys castaneus, Hoplosternum littorale, Pimelodus maculatus, and Trachelyopterus striatulus) and three Characiformes (Astyanax aff. bimaculatus, Oligosarcus hepsetus, and Hoplias malabaricus), representing approximately 70% of the total number of fishes and 64% of the total biomass. We classified fishes into four habitat guilds: (1) a slow-flowing water guild that occupied mud-sand substrate, composed of two Siluriformes in either shallow (< 4 m, i.e., H. littorale) or deep (> 8 m, L. castaneus) waters; (2) a run-dwelling guild that occurs in deep backwaters with clay-mud substrate, composed of the Characiformes A. aff. bimaculatus and O. hepsetus; (3) a run-dwelling guild that occurs in sandy and shallow substrate, composed of T. striatulus; and (4) a fast-flowing guild that occurs primarily along shorelines with shallow mud bottoms, composed of H. malabaricus and P. maculatus. Our hypothesis was confirmed, as different habitat preferences by fishes appear to occur in this regulated river.


Determinamos neste estudo a preferência de habitat de sete espécies de peixes abundantes em um rio regulado do Sudeste do Brasil. Testamos a hipótese de que peixes diferem na preferência de habitat e usam trechos do rio com diferentes características hidráulicas e tipos de substratos. Realizamos amostragens de peixes, utilizando redes de espera e tarrafas em quatro trechos do rio de 1 km de extensão, compreendendo diferentes características do habitat, onde também obtivemos medidas de profundidade, velocidade da água e tipo de substrato. Quatro Siluriformes (Loricariichthys castaneus, Hoplosternum littorale, Pimelodus maculatus e Trachelyopterus striatulus) e três Characiformes (Astyanax aff. bimaculatus, Oligosarcus hepsetus e Hoplias malabaricus) que juntos compreenderam aproximadamente 70% do número total e 64% do peso total de peixes foram estudados. Classificamos os peixes em quatro guildas: (1) peixes que ocorrem em trechos com baixa velocidade de fluxo e substrato constituído predominantemente de lama e areia, compreendendo dois Siluriformes, um de áreas rasas (< 4 m, i.e., H. littorale) e outro de áreas profundas (> 8 m, i.e., L. castaneus); (2) peixes que utilizam rápidos de áreas laterais mais profundas com substrato lamoso, representados pelos pequenos Characiformes, A. aff. bimaculatus e O. hepsetus; (3) peixes que utilizam rápidos que ocorrem em áreas rasas e substrato arenoso, representado por T. striatulus; e (4) peixes de corredeiras que utilizam as margens rasas com fundo lamoso, representados por H. malabaricus e P. maculatus. As espécies estudadas apresentam diferenciação na preferência por variáveis do hábitat, corroborando a hipótese investigada.


Assuntos
Animais , Fauna Aquática/análise , Ecossistema/análise , Rios , Especificidade da Espécie , Peixes/classificação
14.
Biota neotrop. (Online, Ed. port.) ; 12(3): 254-262, Sept. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-655962

RESUMO

A ordem Chiroptera é a segunda maior em riqueza de mamíferos no Brasil e a Mata Atlântica é o bioma com o melhor estado de conhecimento para esse grupo. Em Sergipe, estudos sobre quirópteros ainda são escassos, sendo necessário ampliar as pesquisas com esses animais. O presente trabalho teve como objetivo realizar o inventário de morcegos do Refúgio de Vida Silvestre Mata do Junco (RVSMJ), segunda maior reserva de Mata Atlântica do estado de Sergipe. As coletas foram realizadas durante duas noites por mês, entre fevereiro de 2011 a fevereiro de 2012, exceto junho. Com um esforço de captura de 21.168 m².h foram registrados 189 indivíduos de duas famílias e 14 espécies. Destas, Artibeus planirostris, Chiroderma doriae, Myotis nigricans, Phyllostomus discolor, Trachops cirrhosus e Trinycteris nicefori correspondem a novas ocorrências para a localidade, sendo T. nicefori novo registro para o estado. Phyllostomidae foi a família com maior riqueza e abundância e A. lituratus (N = 67), Carollia perspicillata (N = 45) e Dermanura cinerea (N = 45) foram as espécies mais abundantes. Essas três espécies juntas representam 83,0% dos indivíduos capturados; sendo caracterizadas como generalistas no uso do habitat e dieta. Com relação às guildas alimentares, a maioria das espécies é frugívora (57,1%), devido a metodologia e existência de áreas agrícolas presentes no RVSMJ. O registro de novas espécies para a localidade, juntamente com os parâmetros obtidos de riqueza, abundância e guilda alimentar, contribuem para o aumento do conhecimento dos quirópteros em Sergipe e podem servir de base para estratégias de conservação e manejo dessa área.


The order Chiroptera is the second in mammal species richness in Brazil and the Atlantic Forest is the biome with the best knowledge status for this group. In Sergipe, studies focused on bats are still scarce, being necessary to increase the research on such important taxon. This work aimed to conduct a bat inventory in the Refúgio de Vida Silvestre Mata do Junco (RVSMJ), which is the second largest reserve of Atlantic Forest in the state of Sergipe. Samples were obtained during two nights per month from February 2011 to February 2012, except in June. With a sampling effort of 21,168 m².h, we recorded 189 individuals of two families and 14 species. Among these, Artibeus planirostris, Chiroderma doriae, Myotis nigricans, Phyllostomus discolor, Trachops cirrhosus and Trinycteris nicefori are new occurrences for the location, being T. nicefori also new record for the state. Phyllostomidae was the richest and most abundant family, and A. lituratus (N = 67), Carollia perspicillata (N = 45), and Dermanura cinerea (N = 45) were the most abundant species. These three species accounted for 83.0% of all captured individuals, and were characterized as generalists in habitat use and diet. With respect to feeding guilds, most of the captured species are frugivores (57.1%), probably due to the methodology and existence of agricultural areas present in RVSMJ. The new records here assigned, along with the parameters obtained for richness, abundance and feeding guild, will increase our knowledge on the bats of Sergipe and can be used as a basis for conservation strategies and management at the studied site location.

15.
Biota neotrop. (Online, Ed. port.) ; 11(4): 161-168, Oct.-Dec. 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-622617

RESUMO

O objetivo deste trabalho foi elaborar uma lista das espécies de quirópteros capturados em seis lagoas no Parque Nacional da Restinga de Jurubatiba, Estado do Rio de Janeiro, Brasil. O Parque está localizado a cerca de 180 km a leste da cidade do Rio de Janeiro e abrange os municípios de Macaé, Carapebus e Quissamã. A região é dominada por dunas e cordões arenosos formados no Quaternário. Foram capturados 149 morcegos, pertencentes a três famílias e 14 espécies. A maior parte das espécies capturadas na restinga de Jurubatiba foi de frugívoros, em parte devido à técnica empregada, com redes de neblina, que favorece a captura de indivíduos da família Phyllostomidae. Foram capturadas cinco espécies pouco frequentes em inventários de morcegos (Uroderma magnirostrum, Lasiurus cinereus, Lophostoma brasiliense, Chiroderma villosum e Diaemus youngi). As espécies capturadas variaram entre as lagoas, o que mostra a importância desses ambientes para a manutenção da diversidade de morcegos.


The aim of this study was to perform a list of bat species captured in six lagoons in the Parque Nacional da Restinga de Jurubatiba, Rio de Janeiro State, Brazil. The park is located about 180 km eastward of Rio de Janeiro city and covers the municipalities of Macaé, Carapebus and Quissamã. The region is dominated by sand dunes and sand ridges formed in the Quaternary. We captured 149 bats belonging to three families and 14 species. Most species caught in restinga de Jurubatiba were frugivores, partly due to technique employed, mist-net, that favors the capture of individuals of the Phyllostomidae family. Five species are uncommonly captured in bats inventories (Uroderma magnirostrum, Lasiurus cinereus, Lophostoma brasiliense, Chiroderma villosum and Diaemus youngi). Species caught varied among lagoons, showing the importance of these habitats for maintaining the diversity of bats.

16.
Rev. biol. trop ; 58(1): 447-463, mar. 2010. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-637835

RESUMO

Do live fences help conserve butterfly diversity in agricultural landscapes? In Central America, natural forests have been transformed into agriculture production areas, generating forest fragmentation, desertification, erosion and loss of biodiversity, among other concerns. Different tree cover compositions are kept on these agricultural landscapes, including scattered trees in pastures, live fences, fragments of secondary forests, and riparian forests. These can help in biodiversity conservation because they generate shelter, feeding and reproduction areas, among others. We studied the composition, richness and abundance of diurnal butterflies on two types of live fences in a landscape where pastures are predominant in Costa Rica’s Central Pacific Region. Transects (120x5m) were observed for an hour (two days/habitat) in five multi-strata fences (with several plant species, strata and canopy width) and five simple fences (with smaller and pruned trees). A total of 2 782 butterflies were observed (75 species). The most abundant species were Anartia fatima, Eurema daria, Eurema nise, Hermeuptychia hermes, Junonia evarete and Phoebis philea. Multi-strata fences had more species and can help maintain 56% of the total species observed in secondary and riparian forests. This type of live fence can play an important role in butterfly conservation in livestock areas, and its benefits are influenced by the manner in which farmers manage their land. Rev. Biol. Trop. 58 (1): 447-463. Epub 2010 March 01.


En Centro América, los paisajes agropecuarios mantienen diferentes formas de cobertura arbórea como árboles dispersos, cercas vivas, fragmentos de bosque, bosques ribereños, que pueden generar hábitats apropiados para la conservación de la biodiversidad. El presente estudio caracterizó la composición, riqueza y abundancia de mariposas en dos tipos de cercas vivas presentes en un paisaje dominado por pasturas en el Pacifico Central de Costa Rica. Se seleccionaron un total de cinco cercas vivas por cada tipo de cerca (simples y multiestrato), donde se establecieron franjas de 120x5m que fueron recorridos por espacio de una hora durante dos días/hábitat. Se registró un total de 2 782 individuos, pertenecientes a 75 especies de mariposas. Las especies más abundantes fueron: Anartia fatima, Eurema daría, E. nise, Hermeuptychia hermes, Junonia evarete y Phoebis philea. Las cercas vivas multiestrato presentaron una mayor riqueza y abundancia de especies de mariposas que las cercas vivas simples. Las cercas vivas multiestrato pueden ayudar a mantener el 56% de las especies encontradas en los bosques secundarios y ribereños. Este tipo de cerca viva pueden jugar un papel importante para la conservación de mariposas en áreas de producción pecuaria, y su beneficio está influenciado por el tipo manejo que realizan los productores.


Assuntos
Animais , Biodiversidade , Borboletas/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Árvores , Borboletas/classificação , Densidade Demográfica
17.
Biota neotrop. (Online, Ed. port.) ; 9(4): 91-95, Oct.-Dec. 2009. tab
Artigo em Português | LILACS | ID: lil-543226

RESUMO

A fauna do solo exerce importante papel nos processos ecológicos do ecossistema. Estudos sobre a composição e estrutura dessas comunidades são importantes para entender o seu funcionamento. Assim o objetivo deste trabalho foi avaliar a comunidade de Coleoptera, coletada mediante armadilhas de solo, quinzenalmente, durante o período de treze meses (08/2003-08/2004), na Mata do Mergulhão, Rio de Janeiro. Foram capturados 10.820 espécimes, representados por 24 famílias, sendo considerados abundantes Nitidulidae (4.782 indivíduos), Curculionidae (3.176 indivíduos), Scarabaeidae (2.019 indivíduos) e Staphylinidae (326 indivíduos), capturadas em todo período de coleta. De acordo com as guildas tróficas, os indivíduos das famílias coletados, podem ser agrupados em detritívoros (4.802 espécimes), herbívoros (3.218 espécimes), decompositores (2.019 espécimes), predadores (621 espécimes) e fungívoros (160 espécimes). Foi constatada maior ocorrência de detritívoros (44,4 por cento), herbívoros (29,7 por cento) e decompositores (18,7 por cento). Foram capturados 6.685 exemplares (61,8 por cento) no período de outubro/2003 a março/2004, na estação chuvosa, e 4.135 exemplares (38,2 por cento) na estação seca. Foram observadas maiores capturas nos meses de outubro e dezembro de 2003, e março de 2004.


The soil fauna plays an important role in the ecological function of an ecosystem and studies on the composition and structure of these communities are important to understand your functioning. The objective of our study was to evaluate of community of the soil fauna Coleoptera, collected bimonthly through pitfall trap, from August 2003 to August 2004. A total of 10,820 specimens from 24 families of Coleoptera were captured, but Nitidulidae (4,782 individuals), Curculionidae (3,176), Scarabaeidae (2,019) and Staphylinidae (326) were considered abundant families. According to the trophic guild, the collected individuals can be divided into detritivores (4,802 specimens), herbivores (3,218), decomposers (2,019), predators (621) and fungivoros (160). These results indicate no dominance of a single trophic group, however, the high occurrence of detritivores (44.4 percent), herbivores (29.7 percent) and decomposers (18.7 percent) was registered. About 61.8 percent (6,685 individuals) were captured during October 2003 to March 2004, a rainy period, and 38.2 percent (4,135) during the dry period indicating a pronounced seasonal difference in the relative abundance of individuals sampled. The high frequency of individuals was observed during the October and December, 2003, and March, 2004.

18.
Acta amaz ; 28(3)1998.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454657

RESUMO

The spatial and temporal distribution of a guild of eight diurnal tiger beetle species was studied on a 105 m long transect near the field station of the Reserva Florestal A. Ducke near Manaus (AM), Brazil. The transect followed a path that included both shaded and an open areas. Five of the species, restricted to primary forest, occurrred only in shaded areas of the transect, and three species occurred in open areas. Of all eight species only two of the open habitat species showed no clear seasonality in adult activity. In six species the activity of adults was limited to the rainy season. The most pronounced annual rhythm was found in Pentacomia ventralis, an open habitat species. Activity of adults was limited to October/November. First in-star larvae appeared shortly thereafter. Larval development mainly took place from January to May. The third instar larva entered a dormancy which lasted up to 10 months, and which enabled the synchronisation of emerging adults with annual seasons.


A distribuição espacial e temporal de uma associação de cicindelídeos diurnos foi estudada num transecto de 105 m próximo à estação de campo da Reserva Florestal A. Ducke, perto de Manaus (AM), Brasil. O transecto seguiu uma trilha, incluindo áreas sombrias e ensolaradas. Cinco das espécies, restritas à floresta primária, ocorreram somente nas áreas sombrias do transecto, e três espécies ocorreram em áreas abertas. Das oito espécies, somente duas, dos habitats abertos, não mostraram uma distinta atividade sazonal. Em seis espécies, a atividade foi restrita à época de chuva. O ritmo anual mais pronunciado foi constatado para Pentacomia ventralis, uma espécie de habitats abertos. A atividade de adultos foi limitada a Outubro/Novembro. Larvas do primeiro estádio apareceram logo em seguida. O principal desenvolvimento larval foi de Janeiro até Maio. A larva do terceiro estádio entrou em dormência, com uma duração de até 10 meses, possibilitando assim a sincronização da eclosão dos adultos com as estações do ano.

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