Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy / Biometría de invertebrados de ríos de llanura: desentrañando su bionomía

Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.(AU)

Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.(AU)

Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy / Biometría de invertebrados de ríos de llanura: desentrañando su bionomía

Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.

Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy

RESUMEN Actualmente, es muy reconocido que los invertebrados tienen un rol clave en los ambientes de llanura aluvial neotropicales así como en otros ambientes alrededor del mundo. Sin embargo, se cuenta con muy poca información publicada en relación con su biometría, a pesar de ser una herramienta esencial para muchos tipos de estudios. En este trabajo se obtuvieron relaciones longitud-masa ajustadas por el modelo linearizado (log10 Y = log10a + b log10 X) y diferentes proporciones de materia orgánica promedio ± ES para bivalvos, gastrópodos, quironómidos, efemerópteros, oligoquetos e hirudíneos. Medimos, pesamos, secamos e incineramos hasta cenizas especímenes colectados entre 2005 y 2014 en el río Paraná, Argentina. Las ecuaciones lineales tuvieron valores de ajuste mayores al 75% en la mayoría de las regresiones significativas. Al comparar las pendientes, se encontraron diferencias relacionadas con la ontogenia y filogenia de las taxa. Asimismo, las pendientes resultaron diferentes de las constantes para otras regiones, tipos de ambientes y climas. Asimismo, las proporciones de materia orgánica fueron significativamente diferentes entre invertebrados de acuerdo a su tipo de alimentación. Las ecuaciones y proporciones que obtuvimos facilitarán futuras investigaciones sobre historia de vida, productividad y transferencia de energía en las tramas tróficas de invertebrados en humedales de llanura aluvial y pueden ser empleadas para planificar estrategias de manejo y en proyectos de restauración de ambientes acuáticos.

ABSTRACT Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

CARACTERIZAÇÃO DOS PRODUTORES, SISTEMAS DE CRIAÇÃO E LÃ DE OVINOS NO LITORAL SUL DO PERU

No Peru, a ovinocultura é uma importante atividade para os pequenos produtores, os quais criam esses ruminantes buscando o consumo e venda de subprodutos. Este estudo objetivou caracterizar os ovinocultores, seus sistemas de produção, assim como qualidades macroscópicas e microscópicas da lã, em rebanhos no município de Ite, região Tacna, litoral sul do Peru. Em 2012, foram entrevistados oito pastores dos Humedales e 24 agricultores das chácaras, usando um questionário. Também foram amostradas mechas de lã em 20 ovelhas crioulas dos Humedales, 20 crioulas das chácaras e seis mestiças Hampshire Down. Os resultados evidenciaram dois tipos de ovinocultura familiar, segundo ambiente e tipo de criador, ambos os casos dedicados ao corte com ovinos crioulos e mestiços. Verificou-se pouca assistência técnica e atenção governamental, manejo empírico e rebanhos presentando regular a baixa produtividade. A lã dos três grupos mostrou majoritariamente fibras curtas, apropriadas para processamento têxtil industrial, no entanto, as crioulas dos Humedales apresentaram fibras mais longas, com tendência para uso artesanal. As fibras das ovelhas crioulas eram entrefinas e confortáveis. Em Ite, a ovinocultura é comercial ou de subsistência, mas os produtores conseguem manter-se no mercado, porque a carne ovina é apreciada na região e a criação praticada desde épocas coloniais. Os ovinos crioulos mostraram certas vantagens produtivas, em relação aos mestiços, embora sofram cruzamentos absorventes, que podem causar risco de extinção nesta localidade. Recomenda-se continuar os estudos dos ovinos crioulos de Ite, para conservar e explorar suas qualidades zootécnicas desconhecidas, visando uma ovinocultura sustentável no sul do Peru.

In Peru, sheep farming is an important activity for smallholders, which breed these ruminants seeking the consumption and sale of subproducts. This study aimed to characterize the sheep breeders, their productive systems, as well as macroscopic and microscopic wool qualities, on flocks in the municipality of Ite, Tacna region, southern coast of Peru. In 2012, eight shepherds from Humedales and 24 smallholders from farms were interviewed, using a questionnaire. Also fleeces of wool were sampled on 20 creole sheep from Humedales, 20 creole sheep from farms, and six Hampshire Down crossbreds. Results evidenced two types of family sheep farming, according to environment and type of breeder, both cases dedicated to meat production with creole and crossbred sheep. It was verified a little technical assistance and government attention, empiric management and flocks presenting regular to low productivity. The wool of the three groups showed mostly short fibers, appropriated for industrial textile processing; however, creole sheep from Humedales presented longer fibers, tending to artisanal use. Wool fibers of creole sheep were entrefine and comfortable. In Ite, sheep farming is commercial or subsistence, but the producers can remain on market, because sheep meat is appreciated in the region and the breeding practiced since colonial times. Creole sheep showed certain productive advantages, in relation to crossbreds, although suffer absorbent crossbreedings, which can cause extinction risk at this locality. Is recommend the continuity of studies on Ites creole sheep, to conserve and exploring their unknown zootechnical qualities, aiming a sustainable sheep farming in southern Peru.