RESUMO
Bioindication is a method to assess environmental conditions using indicator organisms. In Colombia, water quality evaluation is mostly performed following the Biological Monitoring Working Party/Colombia method (BMWP/Col), which uses aquatic macroinvertebrates at the taxonomic family level. Studies on potential bioindicators are important to produce comprehensive information on the requirements of macroinvertebrates and their value for water quality bioindication. We studied the larval ecology of several common genera of Odonata from Colombian freshwater ecosystems and assigned an indicator value to each genus. The physical and chemical water characteristics of 1,022 sites surveyed in Colombia from 2005 to 2016 were analyzed using a principal component analysis (PCA). The relationship between environmental conditions and Odonata genera found was studied using multiple logistic regressions between sample coordinates of the first three axes of the PCA and occurrence of the respective genus. We assigned an indicator value for each genus using the logistic regression and the water quality of samples. The highest indicator values were assigned to genera, which were mainly explained by the PCA axis associated with water quality, showed a high odds ratio to this axis, and were found in ecosystems with excellent water quality. The indicator values suggested for each taxon are, Brechmorhoga Kirby, 1894, 8; Macrothemis Hagen, 1868, 4; Micrathyria Kirby, 1889, 4 (Libellulidae); Progomphus Selys, 1854, 7 (Gomphidae); Acanthagrion Selys, 1876, 4; and Argia Rambur, 1842, 7 (Coenagrionidae). Differences in water quality preferences in genera of the same family suggest that higher taxonomic resolution may allow more detailed environmental assessments.
Assuntos
Odonatos , Animais , Colômbia , Ecologia , Ecossistema , Monitoramento Ambiental , LarvaRESUMO
RESUMEN La vegetación riparia es primordial para el funcionamiento de los ecosistemas acuáticos al aportar materia orgánica. Dado que el perifiton juega un rol indispensable en la dinámica de estos ecosistemas y existen pocos trabajos sobre su ecología en el Neotrópico, se planteó la pregunta: ¿Cómo afecta el tipo de cobertura vegetal de la zona riparia, la estructura del fitoperifiton de humedales de la Orinoquía? En noviembre de 2016 se estudiaron 15 humedales con cobertura boscosa y 15 humedales con vegetación herbácea en su zona riparia. Los humedales están ubicados en la zona periurbana de Villavicencio, Meta (Colombia). Se comparó la diversidad algal entre coberturas riparias y se realizaron análisis de Redundancia para determinar que variables ambientales explicaban la composición del fitoperifiton. Se encontraron 467 morfotipos de algas, el 36,2 % perteneció a la clase Zygnematophyceae, 35,3 % a Bacillariophyceae y 16 % a Chlorophyceae. En cuanto a las diatomeas, se encontraron 165 morfoespecies distribuidas en 30 géneros. Eunotia y Pinnularia fueron los más representativos. Los análisis multivariados indicaron que la composición de diatomeas se relacionó con la cobertura vegetal litoral y el carbono orgánico total. El resto del fitoperifiton fue explicado por la temperatura y la conductividad. Modelos de regresión lineal mostraron que la diversidad de diatomeas fue explicada por el número de sustratos, la temporalidad y la cobertura vegetal riparia. Los resultados permiten concluir que en humedales antropizados de la Orinoquía colombiana, el tipo de cobertura vegetal riparia afecta la composición y diversidad de las diatomeas.
ABSTRACT Riparian vegetation is essential for the functioning of aquatic ecosystems by providing organic matter. Given that periphyton plays an indispensable role in the dynamics of these ecosystems and there are few works on its ecology in the Neotropic our research question was: How does the riparian vegetation cover affect the structure of the phytoperiphyton in wetlands of the Orinoquía? In November 2016, we sampled 15 wetlands covered by forest and 15 wetlands covered by herbaceous vegetation in the riparian zone. The wetlands are located in the peri-urban area of Villavicencio, Meta (Colombia). The algal diversity between coverage types was compared and Redundancy Analyses were carried out to determine which environmental variables explain the phytoperiphyton composition. 467 morphotypes of microalgae were found, 36.2 % belonged to the Zygnematophyceae Class, 35.3 % to Bacillariophyceae, and 16 % to Chlorophyceae. 165 morpho-species of diatom distributed in 30 genera were found. Eunotia and Pinnularia were the most representative. The multivariate analyzes indicate that the composition of diatoms was related to the littoral vegetation coverage and the total organic carbon. The rest of the phytoperifiton was explained by temperature and conductivity. Linear regression models showed that the diversity of diatoms was explained by the number of substrates, temporality and the type of riparian coverage. We conclude that in anthropogenic wetlands of the Colombian Orinoquía, the type of riparian vegetation affects the composition and diversity of diatoms.
RESUMO
RESUMEN Los pequeños ríos de los Andes tropicales se han estudiado escasamente y poco se conoce sobre la composición, diversidad y estructura de sus comunidades de macrófitas. En esta investigación se estudiaron las comunidades de plantas acuáticas de 18 pequeños ríos andinos pertenecientes a las cuencas de los ríos La Vieja (Quindío) y Otún (Risaralda) en la ecorregión cafetera colombiana, una de las más afectadas por actividades antrópicas en el país. Se buscó evaluar el efecto del uso del suelo sobre la estructura de las comunidades de macrófitas. Para ello se seleccionaron ríos que nacen y discurren exclusivamente en cada uno de los usos del suelo dominantes en cada cuenca. El muestreo se realizó en dos épocas climáticas distintas del año 2006. La vegetación acuática encontrada en las dos cuencas (54 especies, pertenecientes a 25 familias) presentó riqueza y abundancia menores que las reportadas en otros sistemas acuáticos tropicales y estuvo dominada por especies con alta capacidad de adaptación a ambientes cambiantes o alterados. Se encontró que variables ambientales de los ríos asociadas con el tipo de uso del suelo, como la temperatura, la conductividad y el tipo de sustrato, fueron las que principalmente explicaron la estructura de las comunidades de macrófitas. Los ríos de zonas ganaderas, con dominancia de sustrato fino y valores más altos de temperatura y conductividad, presentaron mayor riqueza y abundancia de especies que los ríos de zonas con uso forestal, caracterizados por una alta cobertura arbórea del cauce, menor temperatura, baja concentración de nutrientes y predominancia de sustrato rocoso.
ABSTRACT Small streams of tropical Andes have been poorly studied. Therefore, there is little information about the structure, dynamics and function of their macrophyte communities. In this research, aquatic plant communities of 18 Andean streams of La Vieja (Quindío) and Otún (Risaralda) river basins were studied; those are some of the basins most affected by anthropic activities in the country. Streams were selected according to their association with the main land's uses of the region in both basins. The aim of the study was to evaluate the effect of land use on the structure of macrophyte communities. Streams running exclusively through each land use were selected. Sampling was done in two different climatic seasons in 2006. Vegetation found (54 species belonging to 25 families) was dominated by species with high capability of adaptation to changing and disturbed environments. Richness and abundance of macrophytes were lower than those reported in other tropical aquatic systems. Variables associated with land use, such as temperature, conductivity and type of substrate of the streams mainly explained the structure of the macrophyte communities: streams running on meat-cattle areas -with higher temperatures, conductivity and dominance of sandy-slimy substrates- had higher macrophyte species richness and abundance than streams of protected-forest areas, with higher coverage of riparian vegetation, lower temperatures and conductivity and rocky substrates.
RESUMO
Se comparó la abundancia relativa de Grundulus bogotensisentre dos cuencas y la dieta entre poblaciones de tres cuencas delaltiplano Cundiboyacense. Entre marzo y junio de 2006 se realizaronmuestreos en 10 localidades utilizando un equipo de electropesca. Laabundancia relativa de cada localidad se expresó como el número deindividuos capturado por hora en un tramo de 100m. Se utilizó untest de Kruskal-Wallis para determinar diferencias significativas en laabundancia relativa entre cuencas. Para cuantificar la dieta se utilizóel método volumétrico y para determinar el grado de similaridadentre cuencas se recurrió a tres análisis multivariados: análisis deescalonamiento multidimensional no métrico (NMDS), análisisde similaridad (ANOSIM) y análisis de porcentaje de similaridad(SIMPER). Se capturaron en total 675 individuos, empleando 600minutos de esfuerzo de captura. La abundancia de la especie en lacuenca del río Bogotá fue significativamente menor respecto a ladel río Suárez. La composición de la dieta y volumen de ítems entrecuencas fue similar. El material consumido fue de origen autóctonoy los ítems más importantes fueron los insectos inmaduros y losmicrocrustáceos. La abundancia relativa de las poblaciones de G.bogotensis en la cuenca del río Bogotá fue menor que en la cuenca delrío Suárez. La cuenca del río Suárez probablemente soporta la mayorabundancia de la especie en todo su rango de distribución y los datossugieren condiciones favorables para la sobrevivencia de la Guapuchaen el lago de Tota. El análisis de la dieta indicó una similaridad mayoral 60% en la utilización del recurso alimentar en las tres cuencas...
To compare the relativeabundance of Grundulus bogotensis in two river basinsand the diet of the populations of three basins in theCundiboyacense plateau, we sampled 10 localities usingelectrofishing equipment between March and June 2006.The relative abundance in each locality was expressedas the number of fish caught per hour on a 100mstretch; any significant differences in relative abundanceamong basins were identified via a Kruskal-Wallis test.To quantify the diet, we used the volumetric method.Similarities between the basins were determined usingthree multivariate analyzes: nonmetric multidimensionalscaling, analysis of similarity and similarity percentages.In the end, we collected a total of 675 individuals during600 minutes of capture effort. The abundance of thisspecies in the Bogotá river basin was significantly lowercompared to that of the Suárez basin. The dietarycomposition, of autochthonous origin, primarilyimmature insects and microcrustaceans and the volumeof items proved similar between the basins. In conclusion,the dietary analysis indicated a similarity exceeding 60%in the feed resource use for the three basins. The relativeabundance of populations of G. bogotensis in the Bogotáriver basin was lower than in the Suárez river basin, thelatter having, possibly, the greatest abundance of thisspecies throughout its range. The data suggests the mostfavorable conditions for the survival of the species inLake Tota...
Comparar a abundância relativa de Grundulus bogotensisentre duas bacias e a dieta entre populações de três bacias do planaltoCundiboyacense. Entre março e junho de 2006 foram realizadascoletas em 10 localidades utilizando equipamento de pesca elétrica. Aabundância relativa da espécie em cada localidade foi expressa comoo número de indivíduos capturados por hora em um trecho de 100mde extensão. Foi utilizado o teste de Kruskal-Wallis para determinardiferenças significativas na abundância relativa entre as bacias.Para quantificar a dieta foi utilizado o método volumétrico e paradeterminar o grau de similaridade entre bacias foram utilizadas trêsanálises multivariadas: análise de escalonamento multidimensionalnão métrico (NMDS), análise de similaridade (ANOSIM) e análise deporcentagem de similaridade (SIMPER). No total foram capturados675 indivíduos, empregando 600 minutos de esforço de captura. Aabundância desta espécie na bacia do rio Bogotá foi significativamentemenor que na bacia do rio Suárez. A composição da dieta e volumedos itens de alimento entre bacias foram similares. Os recursosconsumidos foram de origem autóctone e os itens mais abundantesforam insetos imaturos e microcrustáceos. A abundância relativa daspopulações de G bogotensis na bacia do rio Bogotá foi menor do quena bacia do rio Suárez. A bacia do rio Suárez provavelmente suporta amaior abundância da espécie em toda a área de distribuição e os dadossugerem condições favoráveis para a sobrevivência da Guapucha noLago de Tota. A análise da dieta indicou uma similaridade maior a60% na utilização do recurso alimentar nas três bacias...