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1.
Rev. biol. trop ; 68(2)jun. 2020.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1507692

ABSTRACT

Introducción: Los bosques montanos tropicales se caracterizan por una alta riqueza y endemismo de briófitos. Sin embargo, la diversidad es altamente sensible a cambios microclimáticos relacionados con alteraciones antrópicas. Objetivo: En este estudio, se evaluó la riqueza y composición de briófitos epífitos en los troncos de árboles de bosques montanos alterados y bosques no alterados ubicados en la ladera occidental del Parque Nacional Volcán Barú. Métodos: Los bosques no alterados mostraron alta humedad, mientras que los bosques alterados mostraron altos niveles de luz y temperatura. En cada árbol evaluamos la presencia y cobertura de briófitos epífitos en 160 cuadrantes de 20 × 30 cm. Resultados: Se registraron un total de 86 especies (49 hepáticas y 37 musgos). La riqueza fue positivamente influenciada por la alteración antrópica, donde los bosques alterados presentaron un mayor número de epífitos de sol. La composición de las comunidades difiere entre los dos tipos de bosques, donde las epífitas de sombra fueron restringidas a bosques no alterados, mientras que las epífitas de sol a zonas alteradas. Conclusiones: Las comunidades de briófitos fueron indicadores efectivos de la alteración de los bosques montanos del Parque Nacional Volcán Barú. Por lo tanto, la conservación de los bosques no alterados garantizará la conservación de una rica y diversa comunidad de briófitos epífitos.


Introduction: Tropical montane forests are characterized by high species richness and endemism of bryophytes. However, this diversity is highly sensitive to microclimatic changes related to anthropogenic disturbance. Objective: In this study, we assessed the richness and composition of epiphytic bryophytes on the trunks of trees in undisturbed and disturbed montane forests on the Western slope of the Baru Volcano National Park. Methods: Undisturbed forests were highly humid, while disturbed forests showed high light levels and temperature. In each tree we measured the presence and cover of epiphytic bryophytes in 160 quadrants of 20 × 30 cm. Results: In total, we recorded 86 species (49 liverworts and 37 mosses). Bryophytes richness was positively influenced by disturbance, with disturbed forests showing a high number of sun epiphytes. Bryophyte community composition was different in each forest type, with shade epiphytes confined to primary forests and sun epiphytes restricted to disturbed sites. Conclusions: Bryophyte communities were effective indicators of montane forests disturbance on the Baru Volcano. Thus, protection of the undisturbed forests remnants might help to preserve a rich and diverse community of epiphytic bryophytes.

2.
Rev. biol. trop ; 66(1): 394-402, Jan.-Mar. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-897680

ABSTRACT

Resumen El cambio de uso del suelo por la intensificación de la agricultura contribuye a la fragmentación de los bosques tropicales y la pérdida de la biodiversidad. En este sentido, a diferencia de los sistemas agroforestales (SAF) tradicionales, los SAF modernos son considerados de poca importancia para la conservación de la biodiversidad de los fragmentos de bosque. Sin embargo, existe una tendencia al establecimiento de SAF modernos. Debido a la sensibilidad a los cambios ambientales, se evaluó la diversidad de mariposas en SAF modernos de Coffea arabica y Erythrina poeppigiana (CP) y en combinación con Musa spp. (CPM) o Cordia alliodora (la única especie nativa de los SAF) (CPL), además de fragmentos de bosque muy húmedo premontano (FR) en el Corredor Biológico Volcánica Central-Talamanca, Costa Rica. En seis sitios representativos de cada sistema se establecieron tres transectos paralelos de 80 m cada uno y distanciados a 25 m entre los mismos. Cada cafetal y fragmento de bosque fue muestreado durante 1.5 horas en total para el registro de mariposas. Durante tres fechas de muestreo, se obtuvo un esfuerzo de muestreo de 4.5 horas/sitio y 27 horas en cada SAF y en FR. CP y CPM juntos tuvieron una composición de especies de mariposas diferente a la de CPL y FR. CP y CPM juntos resultaron con las especies de áreas abiertas Hermeuptychia hermes y Anartia jatrophae como indicadoras. CPL resultó con las especies de bosques secundarios Heliconus erato petiverana y Pareuptychia ocirrhoe como indicadoras. Por el contrario, FR resultó con diversas especies indicadoras típicas de bosques continuos tales como Pierella helvina incanescens, Caligo eurilochus y Morpho peleides limpida. Además, la riqueza de especies en FR fue mayor en relación a los SAF. Sin embargo, entre los SAF, CPL resultó con la mayor diversidad (Exp(H')) de especies de áreas cerradas que CP. Así mismo, CPM tuvo una mayor abundancia de mariposas frugívoras que CP y CPL. En bosques fragmentados, los cafetales con sombras exóticas pueden ser mejores hábitats para mariposas de bosques si se combinan con árboles nativos y/o frutales.


Abstract Land use change by the intensification of agriculture contributes to tropical forest fragmentation and biodiversity loss. In this sense, in comparison with traditional agroforestry systems (AFS), modern AFS are considered irrelevant for the conservation of biodiversity of tropical forest fragments. However, there is an increasing trend toward the establishment of different types of modern AFS. Owing to the sensitivity to environmental changes, we evaluated the biodiversity of butterflies in AFS with Coffea arabica and Erythrina poeppigiana (CP), and intermixed with Musa spp. (CPM) or Cordia alliodora (the only native species of AFS) (CPL), as well as premontane very humid forest fragments in the Volcánica Central-Talamanca Biological Corridor, Costa Rica. In six representative sites of each system we set up three parallel 80 m line-transects, separated by a distance of 25 m. Each coffee farm and forest fragment (FR) was surveyed during 1.5 hours to record butterflies. All sites were sampled once a month from May to July 2007. We obtained 4.5 hours of sampling/site, and 27 hours of sampling/habitat. Both CP and CPM together had a butterflies' species composition which differed from CPL and FR. The indicator species of both CP and CPM together were Hermeuptychia hermes and Anartia jatrophae which are typical of open areas. CPL resulted with the species of secondary forests Heliconius erato petiverana and Pareuptychia ocirrhoe as indicators. In contrast, FR resulted with several indicator species typical of closed canopy forests such as Pierella helvina incanescens, Caligo eurilochus, and Morpho peleides limpida. Moreover, the richness of species was similar among coffee AFS. Furthermore, the richness of species of each coffee AFS was lower in comparison with FR. However, among coffee AFS, CPL harbored higher diversity (Exp(H')) of forest butterflies than CP. Also, CPM was higher in abundance of frugivorous butterflies in relation with CP and CPL. In fragmented forests, coffee farms with exotic shade species combined at least with a native tree or fruit species, can be a better habitat for forest butterflies than those dominated by an exotic monospecific shade. Rev. Biol. Trop. 66(1): 394-402. Epub 2018 March 01.

3.
Acta sci., Biol. sci ; 40: 42562-42562, 20180000. ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1460808

ABSTRACT

The degradation of riparian vegetation in low-order streams can cause irreversible environmental damage, biodiversity loss and alter the structure of communities. In this context, the present study evaluated how the level of degradation of riparian vegetation influences the fish assemblage in three low-order streams in the Brazilian Amazon. In each stream, three different stretches were delimited, distributed in the environments of forest, edge and pasture, and the samplings were conducted in three hydrological regimes using dip nets. Influences of the stretches and streams on richness and abundance were tested with GLMM, on the composition with PERMANOVA and on indicator species with IndVal. Species richness was higher in forest environments and lower in pasture; while abundance was higher in pasture and lower in forest. Species composition differed between stretches, streams and in the interaction between stretches and streams, with a strong difference between stretches of forest and pasture environments. Six species dependent of the riparian vegetation were classified as indicators of forest environments; while a generalist species was indicator of pasture. These results reinforce the negative influence of riparian vegetation removal on biological communities and provide subsidies that can help in the conservation and management of these systems.


A degradação da vegetação ripária em riachos de baixa ordem pode causar danos ambientais irreversíveis, perda de biodiversidade e alterar a estrutura das comunidades. Neste contexto, o presente estudo avaliou como o nível de degradação da vegetação ripária influencia a assembleia de peixes em três riachos de baixa ordem na Amazônia brasileira. Em cada riacho, foram delimitados três diferentes trechos, distribuídos nos ambientes de floresta, borda e pastagem, onde as amostragens foram conduzidas em três regimes hidrológicos, usando redes de imersão. As influências dos trechos e dos riachos na riqueza e na abundância foram testadas com GLMM, na composição com PERMANOVA e nas espécies indicadoras com IndVal. A riqueza de espécies foi maior em ambientes de floresta e menor em pastagem, enquanto a abundância foi maior em pastagem e menor em floresta. A composição de espécies diferiu entre trechos, riachos e na interação entre trechos e riachos, com forte diferença entre trechos de ambientes florestais e de pastagem. Seis espécies dependentes da vegetação ripária foram classificadas como indicadoras de ambientes florestais, enquanto uma espécie generalista foi indicadora de pastagem. Estes resultados reforçam a influência negativa da remoção da vegetação ripária sobre as comunidades biológicas e fornecem subsídios que podem auxiliar na conservação e no manejo desses sistemas.


Subject(s)
Animals , Biodegradation, Environmental , Biodiversity , Specimen Handling , Fishes/growth & development
4.
Braz. j. biol ; 77(2): 213-226, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-888745

ABSTRACT

Abstract Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V), and the other is a privately owned farm. Lianas with large diameters (> 13 cm) and tree ferns with great heights (> 19 m) were considered indicators of undisturbed areas (protected areas) because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil.) K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott) Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.


Resumo Os indicadores são aplicados com menores custos e mais rapidez em comparação com levantamentos convencionais, fornecendo respostas rápidas e eficientes que podem facilitar a gestão das áreas protegidas. Nosso objetivo foi selecionar indicadores de vegetação para monitorar áreas protegidas. Para este fim, analisamos o sub-bosque e quantificamos as lianas e fetos arborescentes em áreas protegidas e não-protegidas em busca de espécies indicadoras. Nossas áreas de estudo estão localizadas na região do Vale do Ribeira, sudeste do Estado de São Paulo, Brasil. Uma delas é uma área protegida (categorias da IUCN II e V) e outra uma fazenda de propriedade privada. Lianas com grandes diâmetros (>13 cm) e fetos arborescentes com grandes alturas (>19 m) foram considerados indicadores de áreas não perturbadas (área protegida), pois seu crescimento está diretamente associado com o estágio sucessional das florestas. As espécies indicadoras da área protegida são não pioneiras, como Bathysa australis (A.St.-Hil.) K.Schum., já as da fazenda (não protegida) são pioneiras, como Pera glabrata (Schott) Poepp. ex Baill. e Nectandra oppositifolia Ness. Todos indicadores sugeridos podem ser utilizados em ações de gestão e conservação, especialmente em áreas protegidas, para garantir a manutenção dos remanescentes florestais e para assegurar o cumprimento dos objetivos destas áreas.


Subject(s)
Conservation of Natural Resources , Biodiversity , Rainforest , Trees/growth & development , Brazil , Ferns/growth & development
5.
Braz. j. biol ; 75(1): 1-7, Jan-Mar/2015. tab, graf
Article in English | LILACS | ID: lil-744342

ABSTRACT

The oligochaetes are considered good indicators of ecological conditions and specific types of habitats. Among the factors that influence the distribution of these invertebrates are the water flow and the nature of the substrate. The aim of this study is to describe the composition and distribution of oligochaete species in a first-order stream in Atlantic Forest and try to identify if some species are associated with characteristics of particular types of habitats. In the dry season and in the rainy season, sand and litter samples in two riffle areas and two pool areas were collected in different parts along the stream using a hand net. The greatest observed richness and abundance occurred in sand in the pool, however the greatest estimated richness was obtained for litter in the pool. The Kruskal-Wallis analysis showed effect of the different types of habitat on the abundance and richness of oligochaetes. The Nonmetric Multidimensional Scaling (NMDS) and Multiresponse Permutation Procedure analysis (MRPP) indicated that the variation in the fauna composition had relation with different types of substrates. The indicator species analysis showed that Limnodrilus. hoffmeisteri was an indicator species in both the riffle sand and pool sand and Pristina americana was only an indicator in the pool sand. The high organic matter content in both sandy habitats probably favored the greater abundance of oligochaetes. The results showed that the substrate constitutes an important factor for the local distribution of these invertebrates in streams. The variation of the community structure among mesohabitats and the presence of indicator species of specific types of habitats in the stream demonstrate the importance of environmental heterogeneity for the oligochaetes fauna in forested streams.


Os oligoquetos são considerados bons indicadores de condições ecológicas e de tipos específicos de habitats. Entre os principais fatores que influenciam a distribuição desses invertebrados estão o fluxo da água e a natureza do substrato. O objetivo principal desse estudo foi descrever a composição e distribuição de espécies de oligoquetas de um riacho de primeira ordem da Mata Atlântica e identificar espécies que são características de tipos específicos de habitats. Na estação seca e na estação chuvosa, amostras de areia e folhiço de duas corredeiras e dois remansos foram coletadas em diferentes manchas ao longo de um trecho do riacho usando rede de mão. A maior abundância e riqueza observada ocorreram em areia de remanso. Entretanto, a análise de rarefação mostrou que a maior riqueza estimada foi obtida em folhiço de remanso. A análise de Kruskal-Wallis mostrou o efeito dos diferentes tipos de mesohabitats sobre a abundância e riqueza de oligoquetas. A análise de Escalonamento Multidimensional não- Métrico (NMDS) e a análise de Procedimento de permutação mulitirespostas (MRPP) indicaram que a variação na composição da fauna teve relação com os diferentes tipos de substratos. A análise de espécies indicadoras mostrou que L. hoffmeisteri foi indicadora tanto de areia de corredeira como de remanso e P. americana foi indicadora somente de areia de remanso. O alto conteúdo de material orgânico em ambos habitats arenosos provavelmente favoreceu a maior abundância de oligoquetos. Os resultados mostraram que o substrato constitui um importante fator para a distribuição local desses invertebrados em riachos. A variação da estrutura da comunidade entre os mesohabitats e a presença de espécies indicadoras de tipos específicos de habitats demonstrou a importância da heterogeneidade ambiental para a riqueza e distribuição de oligoquetos em riachos florestados.


Subject(s)
Animals , Ecosystem , Forests , Oligochaeta/classification , Rivers , Animal Distribution , Brazil , Geologic Sediments , Population Density , Seasons , Water Movements
6.
Rev. biol. trop ; 62(2): 795-808, Jun.-Aug. 2014. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-715472

ABSTRACT

In plant communities, the species distribution patterns and their relationships with environmental factors are of central importance in ecology. In San Luis Potosi of Mexico, woodlands of Pinus cembroides and P. johannis are sympatric, but P. cembroides tends to be located in South and Southwest slopes, in more disturbed sites; unlike, P. johannis, is mostly distributed in mesic areas, in North and Northeast slopes. The aim of this study was to analyze the influence of some physical factors on the floristic similarity of pinyon pine P. cembroides and P. johannis. The study area was located in the Sierra San Miguelito, San Luis Potosi, Mexico. We selected 40 sampling units spread over an area of 50km². In each unit, we laid out two 20m long lines perpendicular to each other, in which we recorded cover data of the plant species intercepted. We developed two data matrices, the first one including cover values of 91 species, and the second one, considering seven topographical, climatic, and solar radiation variables. We applied cluster analysis and ordination to explore the influence of environmental variables on the floristic differentiation of pinyon pine woodlands. Clustering showed six groups, the first three characterized by P. cembroides. The ordination showed that variance represented by the first three axes was 65.9%. Axis 1 was positively correlated with altitude and negatively with mean annual temperature; axes two and three, showed low correlation with the variables tested. P. cembroides woodlands and accompanying flora tend to be located in lower altitude, higher mean annual temperature, and mainly in South-Southwestern slopes. In contrast, stands of P. johannis, mixed stands of P. johannis-P. cembroides, and Quercus potosina, were usually founded in greater altitudes, mean annual temperature slightly lower, and North-Northeastern exposure. The sites of these monospecific and mixed woodlands with associated species, indicators of environmental variables, generates the pre-diagnosis of the situation of the communities and their condition, so that future actions can be planned in agreement with the natural balance of the ecosystem.


El conocimiento de los patrones de distribución de especies en las comunidades vegetales y su relación con factores del medio es un objetivo fundamental en ecología. Las comunidades de Pinus cembroides y P. johannis coexisten en diversas regiones de México, pero P. cembroides tiende a distribuirse en laderas de exposiciones sur y suroeste en sitios deteriorados, a diferencia de P. johannis localizados en áreas mésicas en laderas con exposición norte y noreste. El objetivo de este trabajo fue analizar la influencia de algunos factores físicos en la semejanza florística de los piñonares de P. cembroides y P. johannis. El área de estudio se ubica en la Sierra San Miguelito, San Luis Potosí, México. Se seleccionaron 40 unidades de muestreo, distribuidas en una superficie de 50km²; en cada una se trazaron dos líneas de 20m perpendiculares entre sí, donde se registró la cobertura de los individuos interceptados. Se elaboraron dos tipos de matrices de datos: la primera con los valores de cobertura de 91 especies y la segunda, con siete variables topográficas, climáticas y de incidencia solar. Se aplicaron análisis de agrupamiento y de ordenación para explorar la influencia de variables ambientales en la diferenciación florística de los piñonares. El agrupamiento diferenció seis grupos; los tres primeros caracterizados por bosques de P. cembroides. La ordenación mostró que la varianza representada por los tres primeros ejes fue de 65.9%. El eje uno se correlacionó positivamente con la altitud y negativamente con la temperatura media anual y la orientación; los ejes dos y tres mostraron bajos valores de correlación con las variables probadas. Se observó que los piñonares de P. cembroides y flora acompañante, tienden a localizarse en sitios de menor altitud, con mayor temperatura media anual y en laderas con orientación al sur y suroeste. En contraste, los sitios de P. johannis, los de P. johannis-P. cembroides y de éstos con Quercus potosina, por lo regular están ubicados en condiciones de mayor altitud, temperatura media anual baja y con orientación al norte-noreste. La localización de estos bosques monoespecíficos y mixtos junto con las especies asociadas, indicadoras de variables ambientales, genera el pre-diagnóstico de la situación de las comunidades y su condición, para que en el futuro se planifiquen acciones acordes con el balance natural ecosistémico.


Subject(s)
Pinaceae/growth & development , Altitude , Mexico , Population Density , Pinaceae/classification , Temperature
7.
Acta sci., Biol. sci ; 36(1): 67-78, jan.- mar. 2014. ilus, tab
Article in English | LILACS | ID: biblio-849196

ABSTRACT

Periphytic diatoms were sampled from two streams, one located in an urban area and the other located in a rural area, in Maringá, State of Paraná, Brazil. In addition to temporal variability, differences in the assemblage structure between streams were evaluated and correlated with physical and chemical characteristics. Six samples of periphytic diatoms were collected from each stream from July 2007 to June 2008. The streams differed in abiotic factors and in relation to the structure of diatom assemblages and the spatial scale was more important than the temporal scale (ANOVA, p ≥ 0.05; non-metric multidimensional scaling (NMS) stress = 13.73, p = 0.009). The Procrustes analysis (m 2 = 0.7607 and p = 0.0001) showed that variables with the greatest influence on the assemblage structure of diatoms were total nitrogen (TN), electrical conductivity, dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD5) and flow. These results indicate that abiotic variables modified by the land-use had greater influence on the community structure of diatoms than seasonal changes in abiotic variables.


Diatomáceas perifíticas foram amostradas em dois córregos, um localizado na zona urbana e outro na zona rural, situados em Maringá, Paraná, Brasil. Foram avaliadas as diferenças na estrutura da comunidade entre os córregos, relacionando-as às características físicas e químicas, bem como a variabilidade temporal. Seis amostras de diatomáceas perifíticas foram coletadas ao longo de cada córrego, de julho de 2007 a junho de 2008. Os córregos diferiram tanto em relação aos fatores abióticos como em relação à estrutura da comunidade de diatomáceas, e a escala espacial foi mais importante do que a escala temporal (ANOVA, p ≥ 0,05; NMS ­ estresse = 13,73; p = 0,009). A análise de Procrustes (m2 = 0,7607 e p = 0,0001) mostrou que as variáveis com maior influência sobre a estrutura da comunidade de diatomáceas nos córregos estudados foram o nitrogênio total (NT), condutividade, oxigênio dissolvido (OD), demanda química do oxigênio (DQO), demanda bioquímica de oxigênio (DBO5) e velocidade da água. Os resultados indicam que as variáveis abióticas, alteradas pelo uso do solo, tiveram maior influência sobre a estrutura da comunidade de diatomáceas perifíticas do que a variação das condições abióticas devido às estações do ano.


Subject(s)
Diatoms , Food , Periphyton
8.
Rev. biol. trop ; 60(2): 843-856, June 2012. graf, tab
Article in Spanish | LILACS | ID: lil-657823

ABSTRACT

Phorophyte specificity and microenvironmental preferences of corticolous lichens in five phorophyte species from premontane forest of Finca Zíngara, Cali, Colombia). Lichenized fungi or lichens are organisms that have been little studied in the tropics and which distribution is affected by microenvironmental factors and substrate characteristics. The present study aimed to identify phorophyte specificity and microenvironmental preferences of corticolous lichens in five phorophyte species from premontane forest of the farm Finca Zingara in Cali, Colombia. For this, five individuals were selected from five tree species (phorophytes). Lichen species present in a 0.50x0.20m² quadrant located in the trunk of each tree at a height of 1.3m were identified. Substrate parameters such as bark pH, Diameter Breast Height (DBH) and bark structure were measured. Also, microenvironmental factors including temperature, humidity and irradiance were determined. In order to detect phorophyte preferences, a non-metric multidimensional scaling (NMS) and indicator species analysis were made. Spearman correlation analysis was used to assert the relationship between environmental variables and groupings found in the NMS. A total of 69 species of lichens were found, of which 37 were identified to species, 18 to genera and 14 were not determined because they were sterile or had no spores. NMS showed that some individuals of the same tree species were grouped alongside the analysis dimensions, and they were related with the factors of light intensity, temperature and DBH. Only three lichens with preference for certain tree species were found (Arthonia microsperma by Meriania sp., Cladonia ceratophylla and sorediado 8 by Clusia sp.), suggesting absence of phorophyte preferences. Thus, it can be concluded that lichens from the study area do not show phorophyte preference, but their distribution is affected by light, temperature and DBH. Rev. Biol. Trop. 60 (2): 843-856. Epub 2012 June 01.


El objetivo de este trabajo fue evaluar la especificidad de forófito y las preferencias microambientales de los líquenes cortícolas en el Bosque de la Finca Zíngara (Cali, Colombia). Asimismo, se seleccionaron cinco individuos de cinco especies de árboles. Además, se identificaron las especies de líquenes presentes en un cuadrante de 0.50x0.20m2 ubicado en el tronco de cada árbol a 1.3 m de altura. También, se midieron parámetros microambientales como pH de la corteza, diámetro a la altura del pecho (DAP), estructura de la corteza, humedad relativa e irradianza. Para detectar las preferencias de forófito, se realizó un escalamiento no métrico multidimensional (NMS) y un análisis de especies indicadoras. Luego se efectúo un análisis de correlación de Spearman para evaluar la relación entre las variables ambientales y los agrupamientos encontrados en el NMS. Se encontraron 69 especies de líquenes, de los cuales 37 fueron determinados hasta especie, 18 hasta género y 14 no fueron determinados. El resultado del NMS mostró que algunos individuos de la misma especie de árbol se agruparon a lo largo de las dimensiones del análisis, y están relacionados con los factores intensidad de luz, temperatura y DAP. Sólo tres especies mostraron preferencia por ciertas especies de árboles (Arthonia microsperma por Meriania sp., Cladonia ceratophylla y sorediado 8 por Clusia sp.), lo cual sugiere ausencia de preferencias de forófito.


Subject(s)
Ecosystem , Lichens/physiology , Trees , Colombia , Lichens/classification
9.
Ciênc. Saúde Colet. (Impr.) ; 17(6): 1557-1568, jun. 2012. tab
Article in Portuguese | LILACS | ID: lil-626679

ABSTRACT

O presente trabalho objetivou analisar a contaminação de águas superficiais e de chuvas por agrotóxicos em dois municípios do estado do Mato Grosso, Lucas do Rio Verde e Campo Verde, situados entre os maiores produtores de soja, milho e algodão do estado e do país. A metodologia analítica combinou o uso de técnicas cromatográficas em amostras de água superficial e de chuva com análises ecotoxicológicas do impacto da contaminação por agrotóxicos sobre espécies bioindicadoras. Resultados das análises mostraram a presença de resíduos de diferentes agrotóxicos nas amostras de águas superficiais e de chuva coletadas nos dois municípios. Associados a estes dados, resultados das análises ecotoxicológicas mostraram a presença de anomalias em uma espécie de anfíbio anuro coletado em uma das duas localidades, compatíveis com exposição a agrotóxicos. Os resultados aqui apresentados e discutidos apontam para a degradação da qualidade de recursos hídricos da região, causada pelo uso intensivo de agrotóxicos na agricultura, incluindo fontes de água de consumo humano e de chuvas, amplificando o risco de contaminação para além das áreas de plantio.


This study sought to analyze groundwater and rainwater contamination by pesticides in two municipalities (Lucas do Rio Verde and Campo Verde) of Mato Grosso state. The area is Brazil's mid-west situated among the major soybean, corn and cotton producers in the state and the country. The analytical methodology combined chromatographic techniques on groundwater and rainwater samples with eco-toxicological analyses of the impacts of contamination by pesticide on bio-indicator species. The results revealed the presence of different pesticide residues in the groundwater and rainwater samples collected in the two municipalities. In conjunction with this data, results of the eco-toxicological tests revealed the presence of anomalies in a bio-indicator species collected in one of the two study sites compatible with exposure to pesticides. The results presented and discussed here highlight the degradation of water resources in the region, caused by the intensive use of pesticides in agriculture, including the contamination of drinking water sources and rain, broadening the risk of contamination beyond the cultivated areas.


Subject(s)
Agriculture , Groundwater/chemistry , Pesticide Residues/analysis , Pesticides/analysis , Rain/chemistry , Water Pollutants, Chemical/analysis , Water Pollution, Chemical , Brazil
10.
Braz. j. biol ; 72(2): 305-310, May 2012. tab
Article in English | LILACS | ID: lil-639439

ABSTRACT

This study sampled the diversity of Braconidae (Hymenoptera) in three different ecosystems: a degraded pasture, a secondary forest and an area in recovery process using native tree seedlings. The objective was to verify the use of those insects as a tool to check the local conservation by examining Shannon's diversity index. Ten subfamilies were identified, and Microgastrinae was predominant in a number of individuals. The diversity index calculated varies among the sampled areas, thus showing a correlation with vegetation cover with the number of individuals collected and number of subfamilies found. The results showed changes in the community of Braconidae, in the recovery area between the first and second year of study, thereby leading to the conclusion that they are indicators of environmental quality.


Este estudo amostrou a diversidade de Braconidae (Hymenoptera) em três ecossistemas distintos: pastagem degradada, mata secundária e área em processo de recuperação com utilização de mudas de árvores nativas. O objetivo foi verificar a possibilidade de utilização desse grupo de insetos como ferramenta para identificar o estado de conservação local por meio da análise do índice de diversidade de Shannon. Foram identificadas dez subfamílias, com predominância em número de indivíduos de Microgastrinae. Os índices de diversidade calculados permitiram diferenciar as áreas amostradas, apresentando uma correlação da cobertura vegetal com o número de indivíduos coletados e o numero de subfamílias encontradas. O método evidenciou alteração na comunidade de Braconidae na área em recuperação, entre o primeiro e o segundo ano de estudo, demonstrando que são insetos indicadores de qualidade ambiental.


Subject(s)
Animals , Biodiversity , Environmental Monitoring/methods , Hymenoptera/classification , Brazil , Conservation of Natural Resources , Population Density
11.
Rev. biol. trop ; 59(3): 1433-1451, Sept. 2011. ilus, mapas, tab
Article in Spanish | LILACS | ID: lil-638171

ABSTRACT

Ecological indicators of habitat and biodiversity in a Neotropical landscape: multitaxonomic perspective. The use of indicator species to characterize specific ecological areas is of high importance in conservation/ restoration biology. The objective of this study was to identify indicator species of diverse taxa that characterize different landscape units, and to better understand how management alters species composition. We identified two ecomosaics, tropical rain forest and the agricultural matrix, each one comprised of four landscape units. The taxonomic groups studied included birds (highly mobile), butterflies (moderately mobile), terrestrial gastropods (less mobile) and trees (sessile). Sampling efficiency for both ecomosaics was ≥86%. We found 50 mollusks, 74 butterflies, 218 birds and 172 tree species, for a total of 514 species. Using ordination and cluster analysis, we distinguished three habitat types in the landscape: tropical rainforest, secondary vegetation and pastures with scattered trees and live fences. The InVal (≥50%) method identified 107 indicator species, including 45 tree species, 38 birds, 14 butterflies and 10 gastropods. Of these, 35 trees, 10 birds, four butterflies and eight gastropods were forest indicators. Additionally, 10, 28, 10 and two species, respectively per group, were characteristic of the agricultural matrix. Our results revealed a pattern of diversity decrease of indicator species along the rainforest-secondary forest-pasture gradient. in the forest, the gastropods Carychium exiguum, Coelocentrum turris, Glyphyalinia aff. indentata y Helicina oweniana were significantly correlated (p<0.05) with 90% of the other groups of flora and fauna indicator species. These findings suggest that gastropods may be good indicators of forest habitat quality and biodiversity. The secondary vegetation is an intermediate disturbance phase that fosters high diversity in the agricultural matrix. We exemplify a multitaxa approach, including mesofauna, for ecological monitoring of agricultural landscapes. Rev. Biol. Trop. 59 (3): 1433-1451. Epub 2011 September 01.


El uso de especies indicadoras para caracterizar unidades ecológicas específicas es de gran importancia en la biología de la conservación/restauración. El objetivo del estudio fue identificar desde una perspectiva multitaxonómica, las especies que caracterizan distintas unidades de un paisaje. Así, se diferenciaron dos ecomosaicos: bosque tropical lluvioso y matriz agropecuaria con cuatro unidades de paisaje cada uno. Se incluyeron cuatro grupos biológicos: aves (muy móviles), mariposas frugívoras diurnas (moderadamente móviles), gasterópodos terrestres (poco móviles) y árboles (sésiles). La eficiencia de muestreo en los ecomosaicos fue ≥86%. Se registraron 50 especies de moluscos, 74 de mariposas, 218 de aves y 172 de árboles, totalizando 514 especies. Mediante ordenamiento y agrupamiento, se diferenciaron tres tipos de hábitats: bosque tropical lluvioso, vegetación secundaria y potreros con árboles. Aplicando el método InVal (≥50%), se identificaron 107 especies indicadoras, de las cuales 45 fueron árboles, 38 aves, 14 mariposas y diez gasterópodos. De éstas, 35 especies de árboles, diez de aves, cuatro de mariposas y ocho de gasterópodos son indicadoras del bosque. Diez, veintiocho, diez y dos especies (de cada grupo respectivamente) caracterizaron a la matriz agropecuaria. En el bosque, los gasterópodos Carychium exiguum, Coelocentrum turris, Glyphyalinia aff. indentata y Helicina oweniana se correlacionaron significativamente (p<0.05) con 90% de las especies indicadoras. Estos gasterópodos pueden, además de diferenciar la calidad del hábitat, ser indicadoras de la biodiversidad del bosque. La vegetación secundaria representó una fase intermedia de perturbación que propicia alta riqueza en la matriz agropecuaria. De manera que se aporta una perspectiva multitaxonómica que incluye el papel de la mesofauna en el monitoreo ecológico de agropaisajes.


Subject(s)
Animals , Biodiversity , Birds/classification , Butterflies/classification , Ecosystem , Environmental Monitoring/methods , Gastropoda/classification , Trees/classification , Tropical Climate
12.
J Environ Biol ; 2010 Jan; 31(1): 97-100
Article in English | IMSEAR | ID: sea-146334

ABSTRACT

We explored the semi-natural forests in south western Anatolia along a gradient between Mediterranean and continental climates to determine the site requirements of Juniperus excelsa in Turkey. We hypothesized that environmental variables and indicator species can be used to predict differences in occurrence and cover of J. excelsa and can therefore support decision making in reforestation management planning. Plant species composition and environmental variables were assessed in 153 plots. Association between J. excelsa and other plant species and environmental variables were analyzed using Fisher exact probability tests and stepwise discriminant analysis. High altitude (> 1000 m) as a proxy for an Oromediterranean climate, and high surface stoniness as a proxy for low competition by other tree species, are positive site properties for J. excelsa. The tree species avoids Eumediterranean and Supramediterranean plant communities. Twelve plant species, including the herbs Dianthus zonatus, Ajuga chamaepitys and Paronchia carica and the shrub Cotoneaster nummularia may be used as site indicators for J. excelsa restoration. Platanus orientalis, with similar site requirements but at present negatively associated to J. excelsa due to competitive effects, may be considered an additional indicator if stand conversion (harvesting and replacing P. orientalis) is part of the management plan.

13.
J Environ Biol ; 2009 Sept; 30(5): 741-746
Article in English | IMSEAR | ID: sea-146270

ABSTRACT

In this study, a data set from Mediterranean mountain forests of southern Anatolia, consisting of species cover and environmental measures in 99 sample plots was analyzed with cluster analysis, indicator species analysis, MRPP, NMDS and sperman rank correlation. Results illustrated two vegetation gradients related to factor complexes of altitude-landform and parent material-land surface smoothness. Axis I of the ordination was strongly related to limestone, serpantine, conglomerate, marl from parent material group, middle slope from slope position group, concave, convex, linear and undulate from landform group, A I, A II, A III and A IV from altitude group, and rocky and erosion pavement from land surface smoothness group. Axis II was strongly related to limestone, serpantine, smooth surface, rocky surface and A III.

14.
Braz. j. biol ; 68(2): 259-268, May 2008. tab
Article in English | LILACS | ID: lil-486750

ABSTRACT

Aiming to evaluate the potential of Passerine birds as bioindicators of forest fragmentation, we studied the avifauna in the mountain region of the state of Rio de Janeiro by mist-netting between 2001 and 2005. We sampled six sites, including four small fragments (from 4 to 64 ha) in an agricultural area (Teresópolis), one second-growth forest (440 ha - Miguel Pereira) and a continuous forest (10,600 ha, Serra dos Órgãos National Park - SONP). Indicator Species analysis and a Monte Carlo test were run to detect associations between species and sites, considering at least 30 percent of perfect indication and a significant value for the statistical test, only considering species with at least 10 captures. A total of 30 Passerine birds were sampled, and due to their association to the largest area (SONP), we considered Sclerurus scansor, Mionectes rufiventris, Chiroxiphia caudata and Habia rubica as the best indicators for this area. Five species were more captured not by chance in the 440 ha second-growth: Conopophaga melanops, Myiobius barbatus, Myrmeciza loricata, Philydor atricapillus and Schiffornis virescens and no species were related to any small fragment. This analysis has identified specialized Passerine species in many aspects (foraging substract, needs for nesting, rarity status), and it can be a valuable tool for detecting possible bioindicators.


Para avaliar o potencial de Passeriformes como bioindicadores de fragmentação florestal na Mata Atlântica, estudamos a avifauna da região serrana do Rio de Janeiro, utilizando capturas com redes de neblina entre 2001 e 2005. Foram amostradas seis áreas, sendo quatro pequenos fragmentos (de 4 a 64 ha) em áreas agrícolas (Teresópolis), uma mata secundária com cerca de 40 anos (440 ha - Miguel Pereira) e uma área de mata contínua de 10600 hectares (Parque Nacional da Serra dos Órgãos - PARNASO). A análise de espécies indicadoras e o teste de Monte Carlo foram empregados para que se verificassem as espécies mais associadas a cada local amostrado, considerando-se um mínimo de 30 por cento de indicação e valor significativo para o teste mencionado, utilizando-se somente espécies com 10 ou mais capturas. Foi amostrado um total de 30 espécies e, pela sua associação com a maior área (PARNASO), consideramos Sclerurus scansor, Mionectes rufiventris, Chiroxiphia caudata e Habia rubica como as melhores indicadoras. Cinco espécies foram mais capturadas não ao acaso na área de 440 ha: Conopophaga melanops, Myiobius barbatus, Myrmeciza loricata, Philydor atricapillus e Schiffornis virescens. Nenhuma espécie foi associada aos pequenos fragmentos. Como esta análise identificou espécies de Passeriformes especialistas em diversos aspectos (substrato de forrageio, locais de nidificação, status de raridade), ela pode ser uma ferramenta útil na detecção de possíveis bioindicadores.


Subject(s)
Animals , Environmental Monitoring , Passeriformes/classification , Trees , Brazil , Population Density , Population Dynamics
15.
Braz. j. biol ; 61(3)Aug. 2001.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467549

ABSTRACT

The family Psychodidae includes the medically important phlebotomine sand flies and four other subfamilies that have been little studied in the Neotropics. The authors here report the results of a trip to collect psychodids in Parque Estadual do Rio Doce, a national park in Minas Gerais that contains one of the largest surviving areas of Atlantic Forest in Brazil. Collections made by Malaise and CDC light traps as well as from diurnal resting sites included 15 species of Psychodinae and Trichomyiinae, among them Trichomyia dolichopogon sp. nov., T. riodocensis sp. nov. and 13 other species new to science but represented by females only. Twelve species of phlebotomine sand flies (Lutzomyia spp.) were also collected. Collections from an undisturbed area of the park were much richer faunistically than those from an area that was destroyed by fire in 1967 but had since regenerated, suggesting that recovery after environmental disturbances of this type may be prolonged. This pattern was not seen for phlebotomine sand flies, whose greater abundance and species richness in the disturbed section of the park may be related to their dependence on small mammal hosts, known to be more diverse in this type of habitat.


A família Psychodidae inclui além dos flebotomíneos de importância médica mais cinco subfamílias pouco estudadas no neotrópico. Os autores relatam os resultados de uma viagem para coletar psicodódeos no Parque Estadual do Rio Doce (Minas Gerais), o qual contém uma das maiores regiões sobreviventes da Mata Atlântica no Brasil. Amostragens realizadas mediante armadilhas Malaise e de luz (CDC), além de capturas em lugares de repouso diurno, incluíram 15 espécies de Psychodinae e Trichomyiinae, dentre elas Trichomyia dolichopogon sp. nov., T. riodocensis sp. nov. e mais 13 espécies novas à ciência, representadas apenas por fêmeas. Também foram coletadas 12 espécies de flebotomíneos (Lutzomyia spp.). As amostras da área do parque não atingida pelo fogo em 1967 tinham uma diversidade de espécies muito maior que as da área destruída e subseqüentemente regenerada, sugerindo que a recuperação após uma catástrofe ambiental desse tipo pode ser muito prolongada. Esse padrão não foi observado nos flebotomíneos, cuja maior abundância e riqueza de espécies na parte afetada do parque podem ser relacionadas a sua dependência por mamíferos pequenos, os quais atuam como hospedeiros e são os mais diversos neste tipo de ambiente.

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