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1.
Rev. biol. trop ; 66(4): 1721-1740, oct.-dic. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-1003359

ABSTRACT

Resumen Las quebradas están fuertemente influenciadas por su vegetación ribereña y la deforestación afecta a la comunidad acuática. Se estudiaron los efectos de la deforestación sobre la diversidad taxonómica y funcional del ensamblaje de macroinvertebrados acuáticos en cuatro quebradas Andinas colombianas. El estudio incluyó 12 sitios, siete de ellos con cobertura arbórea en sus márgenes en áreas boscosas no perturbadas por la deforestación (estaciones de referencia) y los otros cinco sin cobertura arbórea en áreas deforestadas (estaciones alteradas). Se realizaron cuatro muestreos de campo entre junio 2011 y febrero 2012 y se recolectaron muestras de macroinvertebrados bentónicos utilizando el método D-net con malla de 500 μm y recolección manual, y se midieron diferentes variables fisicoquímicas in situ. Se calcularon los índices de Shannon-Wienner (H ') y Simpson (D). Se aplicaron análisis unidireccionales de varianza ANOVAs a cada variable ambiental y análisis canónicos discriminantes (CDA). Se recolectaron un total 8 370 individuos correspondientes a 80 taxones durante el estudio. La abundancia y diversidad fue mayor en las estaciones localizadas en áreas boscosas no perturbadas. Thraulodes, Anacroneuria y Rhagovelia, se asociaron con valores más altos de Calidad de Bosque de Ribera Andina (QBR-And), Índice de Hábitat Fluvial (IHF), Biological Monitoring Working Party Colombia (BMWP/Col) y temperatura en estaciones de referencia, mientras que Leptonema, Baetodes y Mayobaetis se asociaron con mayores valores de pH y altura sobre nivel del mar en estaciones alteradas. Los principales grupos funcionales tróficos (GFT) en las estaciones de referencia fueron colectores-recolectores/raspadores (27.2 %), raspadores (25.4 %) y depredadores (24.4 %), mientras que en estaciones alteradas fueron: Colectores filtradores (27.5 %), colectores-recolectores/raspadores (17.4 %) y raspadores (15.7 %). Los hábitos de vida más abundantes en las estaciones de referencia fueron agarradores (50.5 %), taxones con tres o más hábitos (28.7 %) y patinadores (16.1 %), mientras que en las estaciones alteradas fueron agarradores (68.1 %), taxones con tres o más hábitos (13.7 %) y excavadores (5.2 %). El conocimiento de las variables que determinan la estructura taxonómica y funcional de los ensamblajes de macroinvertebrados, y cómo responden a impactos como la deforestación, puede ayudar a determinar acciones de protección o restauración de las condiciones ambientales y ecológicas de las quebradas Andinas y los hábitats riparios.(AU)


Abstract The creeks are strongly influenced by their riparian vegetation, and the deforestation affect the aquatic community. The effects of deforestation on taxonomic and functional diversity of aquatic macroinvertebrate assemblage in four Colombian Andean creeks were evaluated. The study included 12 sites, seven of them with arboreal coverage at their margins in forested areas undisturbed by deforestation (reference stations) and the other five without tree cover in deforested areas (altered stations). Four field samplings were carried out between June 2011 and February 2012, and samples of benthic macroinvertebrates were collected using the D-net method with 500 μm mesh and manual collection, and different physicochemical variables were measured in situ. The Shannon-Wienner (H′) and Simpson´s index (D) were calculated. One-way analyses of variance (ANOVAs) to each environmental variable, and canonical discriminant analysis (CDA) to establish differences in environmental variables, taxonomic and functional diversity between references and altered stations were applied. 8 370 macroinvertebrate individuals corresponding to 80 taxa were collected in the study, with 6 758 individuals and 75 taxa in references stations and 1 612 individuals and 50 taxa in altered stations. The reference stations had higher values of diversity and the taxa that made major contributions to the variance between reference and altered stations were Thraulodes, Anacroneuria and Rhagovelia, which were associated with the highest values of Index of Andean riparian vegetation Quality (QBR-And), fluvial habitat index (IHF), Biological Monitoring Working Party Colombia BMWP/Col, EPT index (Ephemeroptera, Plecoptera, and Trichoptera) and temperature in reference stations, whereas Leptonema, Baetodes and Mayobaetis were associated with higher pH and elevation above sea level in altered stations. The main functional feeding groups (FFG) at the reference stations were collectors-gatherers/scrapers CG / SC (27.2 %), scrapers SC (25.4 %) and predators PR (24.4 %), and for altered stations were collectors-filterers CF (27.5 %), collectors-gatherers/scrapers CG / SC (17.4 %) and scrapers SC (15.7 %). The most abundant life habits were clingers Cg (50.5 %), taxa with three or more habits (28.7 %) and skaters Sk (16.1 %), in the reference stations, and clingers Cg (68.1 %), taxa with three or more habits (13.7 %) and burrowers Bu (5.2 %) in the altered stations. The knowledge of the variables that determine the taxonomic and functional structure of the macroinvertebrate assemblages, and how they respond to impacts such as deforestation, can help to determine actions of protection or restoration of the environmental and ecological conditions of the Andean streams and the riparian habitats.(AU)


Subject(s)
Conservation of Natural Resources , Biodiversity , Life Style , Analysis of Variance , Colombia
2.
rev. udca actual. divulg. cient ; 21(2): 519-529, jul.-dic. 2018. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1094754

ABSTRACT

RESUMEN Se estudió la relación entre la diversidad taxonómica y funcional del ensamblaje de aves y la estructura de vegetación, en cuatro estadios de sucesión secundaria de bosque, realizando cinco muestreos, entre junio de 2016 y febrero de 2017, en los que se registraron las aves, mediante puntos de conteo de radio fijo y se caracterizó la estructura de la vegetación de cada sucesión. Se estableció la abundancia, la preferencia, la especificidad de hábitat y el gremio trófico, así como la riqueza y la diversidad de las especies de aves y las relaciones entre la composición de las especies y los gremios tróficos con las variables del hábitat. Se registraron 9.516 individuos de 187 especies, pertenecientes a 42 familias y 15 órdenes. Se determinaron dos agrupaciones, separando los estadios sucesionales SS1 y SS2, de los estadios SS3 y SS4, con una similitud entre los dos grupos del 10%, a nivel taxonómico y del 32%, a nivel funcional. La regeneración natural posterior al abandono de prácticas agropecuarias, permiten un incremento de áreas de bosque secundario que, en la medida en que obtienen mayor complejidad estructural, se asocian con una mayor cantidad de especies con preferencia de hábitat de interior de bosque y un aumento de los gremios tróficos nectarívos y frugívoros.


ABSTRACT The relationships between taxonomic and functional diversity of bird assemblage and vegetation structure in four stages of secondary forest succession were studied. Five field samplings were carried out between June 2016 and February 2017, in which birds were recorded using fixed radius point counts, and the vegetation structure of each successional stage was characterized. Bird species were identified and their habitat preference, specificity and trophic guilds were established. The abundance, preference, habitat specificity and trophic guild, and the richness and diversity of species of birds and relationships between species composition and trophic guilds with habitat variables in the four sequences was established. 9516 individuals from 187 bird species belonging to 42 families and 15 orders were registered. Two clusters separating the SS1 and SS2 of SS3 and SS4 successional stages, were determined, with a similarity between both of 10% at taxonomic level and 32% at functional level. The natural regeneration subsequent to the abandonment of agricultural practices allow an increase in secondary forest areas, which to the extent they get greater structural complexity, are associated with increased number of forest interior species, and an increase of nectarivorous and frugivorous guilds.

3.
Journal of Bacteriology and Virology ; : 41-53, 2017.
Article in English | WPRIM | ID: wpr-225910

ABSTRACT

Purpose of this study was to evaluate the influence of a lotion on the bacterial community in the human forearm skin. The chemical- and natural-based lotions were applied on the left and right inner forearm skins, respectively, of 14 participants, who cleansed forearm skin using sterilized cotton swabs. The germs on cotton swabs were analyzed using libraries of PCR amplicons. The genetic diversity of the bacterial communities detected on the natural-based lotion-applied skin (NLS) was significantly higher than that of the bacterial communities on the chemical-based lotion-applied skin (CLS) in all participants, except two. The diversity was estimated based on operational taxonomic unit (OTU), Chao1, Shannon, and Simpson indices. Bacterial communities obtained from the CLS and NLS were phylogenetically separated into 5 and 3 monophyletic groups, respectively, based on lotion types. The taxonomic distribution of the bacterial communities, which were composed of 198 genera in 14 phyla in the CLS and NLS, respectively, was irregularly and biasedly separated into 2 groups based on the lotion types. Among the 14 phyla, Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria were found to be relatively dominant, and 15 of the 198 genera, including Methylobacterium, Propionibacterium, Pseudomonas, Staphylococcus, Streptococcus, and Bacillus were relatively dominant (>0.5%). The taxonomic distribution of dominant bacterial communities from CLS and NLS was irregularly and biasedly separated without relation to the lotion types. In conclusion, the chemical- and natural-based lotions were responsible for changing or influencing the genetic diversity, phylogenetic separation, and taxonomic distribution of skin bacterial communities.


Subject(s)
Humans , Actinobacteria , Bacillus , Bacteroidetes , Firmicutes , Forearm , Genetic Variation , Methylobacterium , Polymerase Chain Reaction , Propionibacterium , Proteobacteria , Pseudomonas , Skin , Staphylococcus , Streptococcus
4.
Rev. biol. trop ; 64(2): 587-602, abr.-jun. 2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-843300

ABSTRACT

ResumenLa parte norte del Golfo de California es una zona mega diversa de alto endemismo con gran interés económico por las pesquerías multiespecíficas que se desarrollan, principalmente de camarón. Existe carencia de estudios recientes sobre ensamblajes de peces componentes de la fauna acompañante. Por lo que, durante las temporadas de pesca 2009-2010 y 2010-2011 se realizaron 14 viajes de pesca comercial a bordo de 13 barcos camaroneros, con un total de 119 lances, efectuados entre los 5 y 90 m de profundidad. Los 119 lances fueron analizados para evaluar la estructura de la comunidad de peces. Se utilizaron índices de diversidad taxonómica para detectar cambios taxonómicos en la comunidad siguiendo el índice de distinción taxonómica promedio Δ+ y el índice de variación taxonómica Δ* (TAXDEST del programa PRIMER v6). Para la conformación de grupos funcionales se consideró las similitudes de rasgos ecológicos y morfológicos entre las especies. Los resultados mostraron que los índices Δ+ y Δ* estuvieron dentro del promedio estimado y por dentro de los intervalos de confianza al 95 %, se encontraron diferencias significativas entre los índices. Los análisis mostraron una comunidad bien estructurada debido a la gran variedad de formas y funciones de las especies dentro de la comunidad. En la composición de grupos funcionales, el atributo ecológico que más contribuyó para conformación grupos, fue el gremio reproductivo. La estructura de la comunidad fue representada por niveles tróficos intermedios 3-3.9, preferencialmente carnívoros primarios y carnívoros secundarios, dentro de las categorías tróficas de ictiobentófagos y zoobentófagos, pertenecientes a especies demersales de fondos blandos y mayormente de cuerpo fusiforme.Se concluye que el NGC presentó alta redundancia funcional de acuerdo a los grupos funcionales estimados, por lo que se considera un ecosistema estable y de gran diversidad. Es recomendable dar seguimiento a este tipo de estudios utilizando información de esfuerzo pesquero y ambiental, debido a la gran importancia biológica y ecológica del área.


Abstract The Northern Gulf of California (NGC) is a mega diverse area of high endemism with major economic interest because of the multi-specific fisheries developed, mainly shrimp. There is a lack of recent studies on bycatch fish assemblages, so during the fishing seasons from 2009-2010 and 2010-2011, on board 13 shrimp boats, 14 commercial fishing trips were performed from 5 m - 90 m in depth with a total of 119 catches. The 119 catches were analyzed to assess fish community structure using taxonomic diversity indices to detect changes in the community following the taxonomic distinctness average Δ+ and the diversity index Δ* (TAXDEST of the PRIMER v6 program). To confirm the structure of functional groups, we considered similarities of ecologic and morphologic traits among species. The results showed that the indices Δ+ and Δ* were within the expected average and confidence intervals at 95%, finding significant differences between the indices. The analyses showed a well-structured community because of the great variety of forms and functions of the species within the community. In the community of the functional groups, reproduction was the ecological attribute that contributed the most to their structure. The community structure was represented by intermediate trophic levels (3-3.9), preferably primary and secondary carnivores within the trophic categories of predators of benthic ichthyo-fauna that belong to demersal species of soft bottoms and mostly fusiform body. To conclude, the NGC showed high functional redundancy according to the estimated functional groups, thus the ecosystem was considered stable and with great diversity. This type of studies should be followed using fishing and environmental effort due to the great biological and ecologic importance in the area.


Subject(s)
Animals , Male , Female , Biodiversity , Fishes/classification , Population Dynamics , Population Density , Mexico
5.
Biota neotrop. (Online, Ed. port.) ; 15(1): 1-16, 23/01/2015. tab, graf
Article in English | LILACS | ID: lil-732243

ABSTRACT

The state of Sergipe has suffered extreme reduction of its Atlantic Forest area in the last decades. The objective of this study is to present an inventory of the Mata do Crasto flora, the largest Atlantic Forest Remnant in Sergipe (approximately 1,000 ha), located in the Municipality of Santa Luzia do Itanhy. An intensive survey was undertaken with monthly plant collections in the study area, for four years (1995 to 1999). Additionally, collections deposited in herbaria were consulted to complete the species list. A total of 324 species were found, belonging to 84 families and 193 genera. This study adds an additional 29 genera and 96 species to the Sergipe flora as new occurrences. The four most speciose families were the Fabaceae (33 species), Rubiaceae (24 species), Myrtaceae (23 species) and Melastomataceae (15 species), that accounted for ca. 30% of the total species. The taxonomic distinction of the area is very similar to three other lowland forests in Northeastern Brazil, although its species composition is quite distinct.


O estado de Sergipe sofreu extrema redução da área de Mata Atlântica nas últimas décadas. Este trabalho tem como objetivo inventariar a composição florística da Mata do Crasto, maior remanescente de Mata Atlântica de Sergipe (aproximadamente 1.000 ha), situada no Município de Santa Luzia do Itanhy. Um inventário intensivo foi realizado com coletas florísticas na área de estudo por quatro anos (1995 a 1999). Adicionalmente, exsicatas depositadas em herbários foram consultadas para complementar a lista de espécies. Um total de 324 espécies foram identificadas, pertencentes a 84 famílias e 193 gêneros. Este estudo adicionou 96 espécies è flora de Sergipe como novas ocorrências. As famílias com maior número de espécies são Fabaceae (33 espécies), Rubiaceae (24 espécies), Myrtaceae (23 espécies) e Melastomataceae (15 espécies), que juntas somam cerca de 30% do total de espécies. A distinção taxonômica do remanescente é surpreendentemente similar ao de outras florestas de terras baixas no Nordeste do Brasil embora suas espécies sejam bastante distintas.

6.
Braz. j. biol ; 74(4): 991-999, 11/2014. tab
Article in English | LILACS | ID: lil-732331

ABSTRACT

Predicting how anthropogenic activities may influence the various components of biodiversity is essential for finding ways to reduce diversity loss. This challenge involves: a) understanding how environmental factors influence diversity across different spatial scales, and b) developing ways to measure these relationships in a way that is fast, economical, and easy to communicate. In this study, we investigate whether landscape and bioclimatic variables could explain variation in biodiversity indices in macroinvertebrate communities from 39 Atlantic Forest streams. In addition to traditional diversity measures, i.e., species richness, abundance and Shannon index, we used a taxonomic distinctness index that measures the degree of phylogenetic relationship among taxa. The amount of variation in the diversity measures that was explained by environmental and spatial variables was estimated using variation partitioning based on multiple regression. Our study demonstrates that taxonomic distinctness does not respond in the same way as the traditional used in biodiversity studies. We found no evidence that taxonomic distinctness responds predictably to variation in landscape metrics, indicating the need for the incorporation of predictors at multiple scales in this type of study. The lack of congruence between taxonomic distinctness and other indices and its low predictability may be related to the fact that this measure expresses long-term evolutionary adaptation to ecosystem conditions, while the other traditional biodiversity metrics respond to short-term environmental changes.


Prever como as atividades antrópicas podem influenciar os vários componentes da biodiversidade é essencial para encontrar maneiras de reduzir a perda de diversidade. Este desafio envolve: a) a compreensão de como os fatores ambientais influenciam a diversidade em diferentes escalas espaciais e, b) desenvolver formas de medir essas relações de uma maneira rápida, econômica e de fácil comunicação. Neste estudo, nós investigamos se a paisagem e as variáveis bioclimáticas podem explicar a variação nos índices de biodiversidade em comunidades de macroinvertebrados de 39 riachos de Mata Atlântica. Adicionalmente às medidas tradicionais de diversidade, por ex.: riqueza de espécies, abundância e índice de Shannon, nos utilizamos índice de distinção taxonômica que mede o grau de relação filogenética dentre os taxa. A quantidade de variação nas medidas de diversidade que foi explicado por variáveis ambientais e espaciais foi estimada utilizando a variação particionada baseada em regressão múltipla. O presente estudo demonstra que o índice de distinção taxonômica não responde da mesma maneira que os índices tradicionais utilizados em estudos de biodiversidade. Nós não encontramos nenhuma evidência de que a distinção taxonômica responde previsivelmente à variação métricas da paisagem, indicando a necessidade de incorporação de preditores em múltiplas escalas neste tipo de estudo. A falta de congruência entre a distinção taxonômica e outros índices e sua baixa previsibilidade pode estar relacionada com o fato de esta medida expressar adaptações evolutivas de longo prazo para as condições ambientais, enquanto as outras métricas tradicionais respondem às alterações ambientais de curto prazo.


Subject(s)
Animals , Biodiversity , Environmental Monitoring , Invertebrates/classification , Brazil , Forests , Fresh Water
7.
Mycobiology ; : 121-125, 2013.
Article in English | WPRIM | ID: wpr-730068

ABSTRACT

Arbuscular mycorrhizal fungi (AMF) have mutualistic relationships with more than 80% of terrestrial plant species. This symbiotic relationship is ancient and would have had important roles in establishment of plants on land. Despite their abundance and wide range of relationship with plant species, AMF have shown low species diversity. However, molecular studies have suggested that diversity of these fungi may be much higher, and genetic variation of AMF is very high within a species and even within a single spore. Despite low diversity and lack of host specificity, various functions have been associated with plant growth responses to arbuscular mycorrhizal fungal colonization. In addition, different community composition of AMF affects plants differently, and plays a potential role in ecosystem variability and productivity. AMF have high functional diversity because different combinations of host plants and AMF have different effects on the various aspects of symbiosis. Consequently, recent studies have focused on the different functions of AMF according to their genetic resource and their roles in ecosystem functioning. This review summarizes taxonomic, genetic, and functional diversities of AMF and their roles in natural ecosystems.


Subject(s)
Colon , Ecosystem , Efficiency , Fungi , Genetic Variation , Host Specificity , Plants , Spores , Symbiosis
8.
Biota neotrop. (Online, Ed. port.) ; 10(2)abr.-jun. 2010. ilus, tab
Article in English | LILACS | ID: lil-556946

ABSTRACT

The ophiuroids collected during the Oceanographic Expedition PUCK (SONNE-156) in 2001, in the framework of the project "Interactions between productivity and environment along the Chilean continental shelf" were analyzed. Eight samples had ophiuroids; Fifteen species were distributed in the following families: Gorgonocephalidae (2), Asteronychidae (2), Ophiomyxidae (1), Ophiacanthidae (2), Ophiuridae (5), Amphiuridae (1), and Ophiolepididae (2). Four species were recorded for the first time from Chilean waters, i.e., Asteronyx loveni Müller & Troschel, Astrodia tenuispina Verrill, Ophiolimna bairdi (Lyman), and Ophiocten amitinum Lyman, and three are new, i.e., Ophiura (Ophiuroglypha) arntzi sp. nov., Amphiophiura gallardoi sp. nov., and Stegophiura wilhelmi sp. nov.


Se analizan los ofiuroídeos colectados durante la expedición oceanográfica PUCK (SONNE-156) en 2001, en el marco del proyecto "Interacciones entre la productividad y el ambiente a lo largo de la plataforma continental chilena". Ocho muestras con ofiuroídeos contenían un total de 15 especies: Gorgonocephalidae (2), Asteronychidae (2), Ophiomyxidae (1), Ophiacanthidae (2), Ophiuridae (5), Amphiuridae (1), y Ophiolepididae (2). Cuatro especies fueron registradas por primera vez en Chile, i.e., Asteronyx loveni Müller & Troschel, Astrodia tenuispina Verrill, Ophiolimna bairdi (Lyman), y tres son nuevas especies, i.e., Ophiura (Ophiuroglypha) arntzi sp. nov., Amphiophiura gallardoi sp. nov., and Stegophiura wilhelmi sp. nov.

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