ABSTRACT
Profilicollis rancoensis n. sp. is the tenth species of Profilicollis Meyer, 1931 which includes 9 other species mostly known from marine decapod crabs and shore birds. Cystacanths of P. rancoensis are described from the dominant freshwater crab Aegla abtao in Ranco Lake, Chile and are morphologically distinguished from cystacanths of the 9 other species based on a combination of 4 characters. These are body size, number of proboscis hook rows, number of hooks per row, and length of the largest anterior 2-4 hooks. Male and female cystacanths of P. rancoensis are 2.10-3.33 mm long having an ovoid proboscis with 14 rows of 6-7 hooks per row, with the largest anterior 2-4 hooks being 105-110 micrometers long; the anterior trunk has many small spines in 70-80 concentric rings, each with 50-60 spines around them; hook roots are simple, directed posteriorly, about as long as the blades anteriorly with unremarkable anterior manubria; the cephalic ganglion are in mid-receptacle just anterior to the level of the anterior trunk; the lemnisci are long and slender; the testes are in the anterior trunk, posterior trunk, or one in each; the primordia of 2 tubular cement glands are evident; strong bundles of fibers link the anterior and posterior trunk; and the posterior trunk has a corrugated surface cuticula. Molecular analysis (COI and 18S) sequences coincided with the morphology and support its taxonomy. The phylogenetic profile revealed that P. rancoensis n. sp. fell into the Profilicollis clade. Both sequences showed low genetic variation, and three different haplotypes were found. The new species was more closely related to P. botulus (Van Cleave, 1916) Witenberg, 1932 than to other Profilicollis species.
Title: Révision du concept de Profilicollis Meyer, 1931 avec la description de Profilicollis rancoensis n. sp. (Acanthocephala, Polymorphidae) du crabe d'eau douce Aegla abtao Schmitt, 1942 (Decapoda, Anomura) au Chili, avec une clé des espèces congénères. Abstract: Profilicollis rancoensis n. sp. est la dixième espèce de Profilicollis Meyer, 1931 qui comprend neuf autres espèces principalement connues de crabes décapodes marins et d'oiseaux de rivage. Les cystacanthes de P. rancoensis sont décrits chez le crabe d'eau douce dominant Aegla abtao dans le lac Ranco, au Chili et se distinguent morphologiquement des cystacanthes des neuf autres espèces sur la base d'une combinaison de quatre caractères. Il s'agit de la taille du corps, du nombre de rangées de crochets du proboscis, du nombre de crochets par rangée et de la longueur des 2 à 4 crochets antérieurs les plus grands. Les cystacanthes mâles et femelles de P. rancoensis mesurent de 2,10 à 3,33 mm de long et ont une trompe ovoïde avec 14 rangées de 6 à 7 crochets par rangée, les 2 à 4 crochets antérieurs les plus grands mesurant 105 à 110 micromètres de long ; le tronc antérieur a de nombreuses petites épines en 70-80 anneaux concentriques chacun avec 50-60 épines ; les racines des crochets sont simples, dirigées vers l'arrière, à peu près aussi longues que les lames vers l'avant avec une manubrie antérieure sans particularité ; les ganglions céphaliques sont au milieu du réceptacle juste en avant du niveau du tronc antérieur ; les lemnisques sont longs et minces ; les testicules sont dans le tronc antérieur, le tronc postérieur ou un dans chacun ; les ébauches des 2 glandes cémentaires tubulaires sont évidentes ; de solides faisceaux de fibres relient le tronc antérieur et postérieur ; le tronc postérieur a une cuticule à surface ondulée. Les séquences d'analyse moléculaire (COI et 18S) coïncidaient avec la morphologie et confirmaient sa taxonomie. Le profil phylogénétique a révélé que P. rancoensis n. sp. appartient au clade Profilicollis. Les deux séquences ont montré une faible variation génétique et trois haplotypes différents ont été trouvés. La nouvelle espèce était plus proche de P. botulus (Van Cleave, 1916) Witenberg, 1932 que des autres espèces de Profilicollis.
Subject(s)
Acanthocephala , Anomura , Helminthiasis, Animal , Animals , Female , Male , Phylogeny , Chile , LakesABSTRACT
The Cautín River is closely related with the economic development of Temuco city, (38°S; Chile). Existing knowledge of the Cautín River is limited to information about its biological characteristics as a reference for the evaluation and assessment of water quality. The object of this study was to develop taxonomic characterisation of the benthic macroinvertebrates along the main course of the Cautín River, and to study the community structure using correlation analysis between community parameters. To carry out this research, the macroinvertebrate community was studied in 10 sampling sites distributed along the main course of the river. The samples were taken in summer (1997 and 2000), when optimal hydrological conditions existed. Analysis of the samples showed that the benthic fauna was composed of 56 taxa, the dominant group being insects with 48 taxa. Three main sectors were recognized in the course of the Cautín River: high, middle and low. Each sector has restricted-distribution species, while other species are widely distributed along the river. These distribution patterns seem to be influenced by dissolved oxygen concentration, temperature, altitudinal distribution and anthropo-cultural activity, present at every sampling site. Finally, this research provides a first approach to the biology of the Cautín River. Further studies could be planned on the basis of this knowledge to investigate water quality indicators based on macroinvertebrate communities.
O rio Cautín está intimamente relacionado ao desenvolvimento econômico da cidade de Temuco (38°S; Chile). Quanto ao conhecimento total do rio Cautín, existem informações limitadas sobre as características biológicas que podem servir de referência para a avaliação da qualidade da água. Este estudo tem o objetivo de caracterizar os macroinvertebrados bentônicos taxonomicamente ao longo do curso principal do rio Cautín e estudar a estrutura da comunidade usando análise de correlação entre os parâmetros dela. Para realizar esta pesquisa, a comunidade de macroinvertebrados foi estudada em dez locais de estudo distribuídos ao longo do rio principal. As amostras foram coletadas no verão (1997 e 2000), em razão das condições hidrológicas ideais. A análise das amostras mostrou que a fauna bentônica é composta de 56 táxons, sendo o grupo dominante o de insetos com 48 táxons. Na distribuição do principal no curso do rio, três setores são reconhecidos: alto, médio e baixo no rio Cautín. Cada setor possui espécies de distribuição restrita e outro com ampla distribuição ao longo do rio. Esses padrões de distribuição parecem influenciar a concentração de oxigênio dissolvido, a temperatura, a distribuição altitudinal e a atividade antropocultural desenvolvida em todos os locais de amostragem. Finalmente, esta pesquisa fornece uma primeira abordagem biológica do rio Cautín e, de acordo com esses conhecimentos, um estudo posterior pode ser planejado em relação aos indicadores de qualidade da água e com base nas comunidades de macroinvertebrados.
Subject(s)
Animals , Rivers , Invertebrates , Chile , Environmental Monitoring , Cities , EcosystemABSTRACT
Abstract The Cautín River is closely related with the economic development of Temuco city, (38°S; Chile). Existing knowledge of the Cautín River is limited to information about its biological characteristics as a reference for the evaluation and assessment of water quality. The object of this study was to develop taxonomic characterisation of the benthic macroinvertebrates along the main course of the Cautín River, and to study the community structure using correlation analysis between community parameters. To carry out this research, the macroinvertebrate community was studied in 10 sampling sites distributed along the main course of the river. The samples were taken in summer (1997 and 2000), when optimal hydrological conditions existed. Analysis of the samples showed that the benthic fauna was composed of 56 taxa, the dominant group being insects with 48 taxa. Three main sectors were recognised in the course of the Cautín River: high, middle and low. Each sector has restricted-distribution species, while other species are widely distributed along the river. These distribution patterns seem to be influenced by dissolved oxygen concentration, temperature, altitudinal distribution and anthropo-cultural activity, present at every sampling site. Finally, this research provides a first approach to the biology of the Cautín River. Further studies could be planned on the basis of this knowledge to investigate water quality indicators based on macroinvertebrate communities.
Resumo O rio Cautín está intimamente relacionado ao desenvolvimento econômico da cidade de Temuco (38°S; Chile). Quanto ao conhecimento total do rio Cautín, existem informações limitadas sobre as características biológicas que podem servir de referência para a avaliação da qualidade da água. Este estudo tem o objetivo de caracterizar os macroinvertebrados bentônicos taxonomicamente ao longo do curso principal do rio Cautín e estudar a estrutura da comunidade usando análise de correlação entre os parâmetros dela. Para realizar esta pesquisa, a comunidade de macroinvertebrados foi estudada em dez locais de estudo distribuídos ao longo do rio principal. As amostras foram coletadas no verão (1997 e 2000), em razão das condições hidrológicas ideais. A análise das amostras mostrou que a fauna bentônica é composta de 56 táxons, sendo o grupo dominante o de insetos com 48 táxons. Na distribuição do principal no curso do rio, três setores são reconhecidos: alto, médio e baixo no rio Cautín. Cada setor possui espécies de distribuição restrita e outro com ampla distribuição ao longo do rio. Esses padrões de distribuição parecem influenciar a concentração de oxigênio dissolvido, a temperatura, a distribuição altitudinal e a atividade antropocultural desenvolvida em todos os locais de amostragem. Finalmente, esta pesquisa fornece uma primeira abordagem biológica do rio Cautín e, de acordo com esses conhecimentos, um estudo posterior pode ser planejado em relação aos indicadores de qualidade da água e com base nas comunidades de macroinvertebrados.
ABSTRACT
The Cautín River is closely related with the economic development of Temuco city, (38°S; Chile). Existing knowledge of the Cautín River is limited to information about its biological characteristics as a reference for the evaluation and assessment of water quality. The object of this study was to develop taxonomic characterisation of the benthic macroinvertebrates along the main course of the Cautín River, and to study the community structure using correlation analysis between community parameters. To carry out this research, the macroinvertebrate community was studied in 10 sampling sites distributed along the main course of the river. The samples were taken in summer (1997 and 2000), when optimal hydrological conditions existed. Analysis of the samples showed that the benthic fauna was composed of 56 taxa, the dominant group being insects with 48 taxa. Three main sectors were recognised in the course of the Cautín River: high, middle and low. Each sector has restricted-distribution species, while other species are widely distributed along the river. These distribution patterns seem to be influenced by dissolved oxygen concentration, temperature, altitudinal distribution and anthropo-cultural activity, present at every sampling site. Finally, this research provides a first approach to the biology of the Cautín River. Further studies could be planned on the basis of this knowledge to investigate water quality indicators based on macroinvertebrate communities.
O rio Cautín está intimamente relacionado ao desenvolvimento econômico da cidade de Temuco (38°S; Chile). Quanto ao conhecimento total do rio Cautín, existem informações limitadas sobre as características biológicas que podem servir de referência para a avaliação da qualidade da água. Este estudo tem o objetivo de caracterizar os macroinvertebrados bentônicos taxonomicamente ao longo do curso principal do rio Cautín e estudar a estrutura da comunidade usando análise de correlação entre os parâmetros dela. Para realizar esta pesquisa, a comunidade de macroinvertebrados foi estudada em dez locais de estudo distribuídos ao longo do rio principal. As amostras foram coletadas no verão (1997 e 2000), em razão das condições hidrológicas ideais. A análise das amostras mostrou que a fauna bentônica é composta de 56 táxons, sendo o grupo dominante o de insetos com 48 táxons. Na distribuição do principal no curso do rio, três setores são reconhecidos: alto, médio e baixo no rio Cautín. Cada setor possui espécies de distribuição restrita e outro com ampla distribuição ao longo do rio. Esses padrões de distribuição parecem influenciar a concentração de oxigênio dissolvido, a temperatura, a distribuição altitudinal e a atividade antropocultural desenvolvida em todos os locais de amostragem. Finalmente, esta pesquisa fornece uma primeira abordagem biológica do rio Cautín e, de acordo com esses conhecimentos, um estudo posterior pode ser planejado em relação aos indicadores de qualidade da água e com base nas comunidades de macroinvertebrados.
Subject(s)
Benthic Fauna/analysis , Benthic Fauna/classification , Water Microbiology , Water QualityABSTRACT
Abstract The Toltén river is located in the 137 years old Araucania region, Chile (38° S), and is characterized by low alterations through human interference due agriculture and towns in its surrounding basin, the presence of native fishes and salmonids, and by its lake effluent regime originated from Villarrica lake. The aim of the present study was to make a review of ecological role of the benthic inland water macroinvertebrates as preys for native fishes of the River Toltén, in order to understand their importance in the ecosystem of the river. The literature revealed that the main prey for native fishes are Chironomidae larvae, nevertheless there are not specific reports for Tolten river. The exposed results are similar with similar native species for Patagonia, and these native species would have prey for introduced salmonids, or these species would have prey competition with introduced salmonids in according to the literature descriptions for Argentinean and Chilean Patagonia.
Resumo O rio Toltén está localizado na região da Araucanía, com 137 anos de idade, Chile (38° S), e é caracterizado por baixas alterações por interferência humana devido à agricultura e cidades da bacia circundante, pela presença de salmonídeos e pelo regime de efluentes dos lagos. do lago Villarrica. O objetivo do presente estudo foi fazer uma revisão do papel ecológico dos macroinvertebrados bentônicos de águas interiores do rio Toltén, a fim de entender sua importância no ecossistema do rio. A literatura revelou que as principais presas de peixes nativos são as larvas de Chironomidae, no entanto, não há relatos específicos para o rio Tolten. Os resultados expostos são semelhantes com espécies nativas semelhantes para a Patagônia, e essas espécies nativas teriam presa por salmonídeos introduzidos, ou essas espécies teriam competição de presas com salmonídeos introduzidos de acordo com as descrições da literatura para a Patagônia Argentina e Chilena.
Subject(s)
Humans , Animals , Aged, 80 and over , Ecosystem , Rivers , Lakes , Chile , FishesABSTRACT
This study evaluates the potential use of archaeological otoliths of Genidens barbus (Cuvier and Valenciennes) as a tool to study fish behavior and hunter-gatherers procurement strategies on the North Patagonian coast. The studied samples come from the San Antonio archaeological locality dated at ca. 1000-800 14C yr BP (Late Holocene). To assess whether exposure to fire significantly affects the otolith Sr:Ca and Ba:Ca ratios, burned and unburned modern lapilli otoliths have been analyzed by Laser Ablation Inductively Coupled Plasma Mass Spectrometry and no statistically significant differences were found between the results of both treatments. Core-to-edge chemical time series were carried out on ancient otoliths (ca. 1000 14C yr BP) in order to study the fish life history. Three amphidromous patterns were found for ancient samples. The capture environments and seasons inferred by the otolith edge chemistry and marginal increase, respectively, suggest a location in high salinity water (estuary and sea) in summer. Finally, to estimate the size of archaeological fish, a linear regression between total length and otolith length was constructed using 70 modern catfish otoliths. The size variability (358-610 mm) might indicate the use of non-selective capture techniques, probably nets, by hunter-gatherer groups.
ABSTRACT
Abstract The Cautin river is located in the 137 years old Araucania region, Chile (38°S), and is characterized by alterations through human interference due agriculture and towns in its surrounding basin, the presence of salmonids, and by its mixed regime, originated from snow melting in summer and rains in winter. The aim of the present study was to make a review of the inventory and ecological role of the benthic inland water macroinvertebrates of the River Cautin, in order to understand their importance in the ecosystem of the river. The fauna of this river includes a fauna composed of endemic and introduced fish, which has, however, been only poorly studied until now. The literature revealed the presence of abundant populations of Diptera, Trichoptera and Ephemeroptera larval stages, and few crustaceans specifically amphipods and freshwater crabs along the river's course. Many of these macroinvertebrates are prey for both introduced salmonids and native fishes. Similar results have been reported for other southern Argentinean and Chilean Patagonian rivers.
Resumo O rio Cautin está localizado na região de Araucania, no Chile (38°S), é caracterizado por alterações através da interferência humana devido à agricultura e as cidades da bacia circundante, a presença de salmonídeos e pelo seu regime misto, originado pela queda de neve verão e chuvas no inverno. O objetivo do presente estudo foi fazer uma revisão do papel ecológico dos macroinvertebrados bentônicos das águas interiores do rio Cautin, para entender sua importância no ecossistema do rio. A fauna deste rio inclui uma fauna composta de espécies de peixes endêmicos e introduzidos, que, no entanto, tem sido mal estudada até agora. A literatura revelou a presença de abundantes populações de estádios de larvas Diptera, Trichoptera e Ephemeroptera, e poucos crustáceos especificamente anfípodes e caranguejos de água doce ao longo do curso do rio. Muitos desses macroinvertebrados são presas tanto para salmonídeos introduzidos quanto para peixes nativos. Resultados semelhantes foram relatados para outros rios sul da Patagônia Chilena e Argentina.
Subject(s)
Animals , Ecosystem , Fishes , Invertebrates , Chile , Population Dynamics , Environmental Monitoring , Food Chain , RiversABSTRACT
The distribution, composition, and transport of both dissolved and particulate organic carbon (DOC and POC) were studied across a terrestrial - marine transition system in the Chilean North-Patagonia (41°S). At the land-fjord boundary we reported: (i) high concentrations of both silicic acid (up to 100⯵M) and integrated chlorophyll a (62â¯mgâ¯m-2), (ii) dominance of nanophytoplankton (63%), humic-, terrigenous-derived, and protein-like DOC (19 and 36%, respectively), and (iii) a shallow photic zone (12â¯m depth). In contrast, the estuarine-ocean boundary was characterized by (i) high concentrations of nitrate and phosphate (20 and 2⯵M respectively) and low chlorophyll a concentration (11â¯mgâ¯m-2), (ii) dominance of microphytoplankton (59%) and tyrosine-like C3 autochthonous DOC (34%), and (iii) a deep photic zone (29â¯m depth). Allochthonous DOC input at the fjord head and the ocean accounted for 60% and 10% of total DOC, respectively. The input of humic-like substances was enhanced by intense forestry and agriculture activity around the Puelo River watershed, contributing from 50% to 14% of total DOC along the fjord - ocean transect. In contrast, autochthonous tyrosine-like substances increased from 25% to 41% of total DOC, highlighting the role of bacterial metabolism in regulating DOM composition. The high correlation (R2â¯=â¯0.7) between the UVC-humic:UVA-humic ratio and salinity suggest that processes associated to freshwater input impinged on the DOC chemical characteristics and origins. Overall, our observations support the view that climate warming (freshwater input) and anthropogenic practices (aquaculture) boost the mobilization of terrestrial carbon pools and their intrusion into coastal ocean areas, a process that should be given more attention in climate prediction models.
ABSTRACT
Zinc (Zn) bioaccumulation and trophic transfer were analyzed in the food web of Lake Nahuel Huapi, a deep, unpolluted ultraoligotrophic system in North Patagonia. Benthic macroinvertebrates, plankton, and native and introduced fish were collected at three sites. The effect of pyroclastic inputs on Zn levels in lacustrine food webs was assessed by studying the impact of the eruption of Puyehue-Cordón Caulle volcanic complex (PCCVC) in 2011, by performing three sampling campaigns immediately before and after the PCCVC eruption, and after 2 years of recovery of the ecosystem. Zinc trophodynamics in L. Nahuel Huapi food web was assessed using nitrogen stable isotopes (δ15N). There was no significant increase of Zn concentrations ([Zn]) in L. Nahuel Huapi biota after the PCCVC eruption, despite the evidence of [Zn] increase in lake water that could be associated with volcanic ash leaching. The organisms studied exhibited [Zn] above the threshold level considered for dietary deficiency, regulating Zn adequately even under a catastrophic situations like PCCVC 2011 eruption. Zinc concentrations exhibited a biodilution pattern in the lake's food web. To the best of our knowledge, present research is the first report of Zn biodilution in lacustrine systems, and the first to study Zn transfer in a freshwater food web including both pelagic and benthic compartments.
Subject(s)
Aquatic Organisms/metabolism , Environmental Exposure/analysis , Food Chain , Volcanic Eruptions , Water Pollutants, Chemical/metabolism , Zinc/metabolism , Animals , Argentina , Environmental Monitoring , Fishes/metabolism , Invertebrates/metabolism , Lakes , Plankton/metabolismABSTRACT
Agriculture represents the second most important economic activity in the North Patagonian Region of Argentina and non-selective insecticides are still being used with significant implications to the quality of the environment. The range of concentrations (µg/L) determined for azinphosmethyl, chlorpyrifos, and carbaryl in drainage channels were from non-detected to 1.02, 1.45, and 11.21, respectively. Macroinvertebrate abundance and taxon richness in drainage channels were significantly lower in November compared to the other sampling months (October, February). The decrease in taxon richness observed in November was associated with chlorpyrifos and azinphosmethyl peak concentrations. The most remarkable changes were the decrease in sensitive taxa such as Baetidae and the increase in some tolerant taxa such as Chironomidae and Gastropoda.For all three pesticides, the acute hazard quotient exceeded the risk criteria for invertebrates. The effects of the three pesticides on aquatic organisms, characterized by joint probability curves, showed that the LC50 of 10% of the species were exceeded five and three times by the concentrations of azinphosmethyl and chlorpyrifos during the study period, respectively. However, the correlation between the pesticide concentrations and both taxon richness and abundance of macroinvertebrates at each site (irrigation and drainage channels) was indicative that only chlorpyrifos was negatively correlated with both parameters (Spearman r2 - 0.61, p = 0.0051 and Spearman r2 - 0.59, p = 0.0068 for taxon richness and abundance correlation, respectively). We conclude that macroinvertebrate assemblages in drainage channels were highly affected by chlorpyrifos levels.
Subject(s)
Aquaporins/chemistry , Chlorpyrifos/chemistry , Gastropoda/chemistry , Insecticides/analysis , Pesticides/chemistry , Water/analysis , Agriculture , Animals , Argentina , Insecticides/chemistryABSTRACT
Silver (Ag) is a pollutant of high concern in aquatic ecosystems, considered among the most toxic metallic ions. In lacustrine environments, contaminated sediments are a source of Ag for the food web. Chironomidae (Insecta: Diptera) are the most abundant, diverse, and representative insect groups in aquatic ecosystems. Chironomid larvae are closely associated to benthic substrates and link primary producers and secondary consumers. Given their trophic position and their life habits, these larvae can be considered the entry point for the transference of Ag, from the benthic deposit to the higher trophic levels of the food web. Previous studies in lakes from Nahuel Huapi National Park (Northern Patagonia) showed Ag enrichment over background levels (0.04-0.1 µg g-1 dry weight) both in biota (bivalves and fish liver) and sediments from sites near human settlements. The aim of this study was to analyze the role of chironomids in the transference of Ag from the benthic reservoir of Lake Moreno Oeste to the food web. The concentration of Ag in chironomid larvae tissue ranged from 0.1 to 1.5 µg g-1 dry weight, reaching a bioaccumulation factor up to 17 over substrates and depending on the associated substrate type, feeding habitats, larval stage, and season. The main Ag transfer to higher trophic levels by chironomids occurs in the littoral zone, mostly from larvae inhabiting submerged vegetation (Myriophyllum quitense) and sediment from vegetated zones. This study presents novel evidence of the doorway role played by chironomid larvae in Ag pathways from the sediments into food webs of freshwater ecosystems.
Subject(s)
Chironomidae/metabolism , Environmental Monitoring/methods , Lakes/chemistry , Larva/metabolism , Silver/analysis , Water Pollutants, Chemical/analysis , Animals , Argentina , Bivalvia/metabolism , Ecosystem , Fishes/metabolism , Food Chain , Seasons , Silver/metabolism , Water Pollutants, Chemical/metabolismABSTRACT
Abstract The Cautin river is located in the 137 years old Araucania region, Chile (38°S), and is characterized by alterations through human interference due agriculture and towns in its surrounding basin, the presence of salmonids, and by its mixed regime, originated from snow melting in summer and rains in winter. The aim of the present study was to make a review of the inventory and ecological role of the benthic inland water macroinvertebrates of the River Cautin, in order to understand their importance in the ecosystem of the river. The fauna of this river includes a fauna composed of endemic and introduced fish, which has, however, been only poorly studied until now. The literature revealed the presence of abundant populations of Diptera, Trichoptera and Ephemeroptera larval stages, and few crustaceans specifically amphipods and freshwater crabs along the rivers course. Many of these macroinvertebrates are prey for both introduced salmonids and native fishes. Similar results have been reported for other southern Argentinean and Chilean Patagonian rivers.
Resumo O rio Cautin está localizado na região de Araucania, no Chile (38°S), é caracterizado por alterações através da interferência humana devido à agricultura e as cidades da bacia circundante, a presença de salmonídeos e pelo seu regime misto, originado pela queda de neve verão e chuvas no inverno. O objetivo do presente estudo foi fazer uma revisão do papel ecológico dos macroinvertebrados bentônicos das águas interiores do rio Cautin, para entender sua importância no ecossistema do rio. A fauna deste rio inclui uma fauna composta de espécies de peixes endêmicos e introduzidos, que, no entanto, tem sido mal estudada até agora. A literatura revelou a presença de abundantes populações de estádios de larvas Diptera, Trichoptera e Ephemeroptera, e poucos crustáceos especificamente anfípodes e caranguejos de água doce ao longo do curso do rio. Muitos desses macroinvertebrados são presas tanto para salmonídeos introduzidos quanto para peixes nativos. Resultados semelhantes foram relatados para outros rios sul da Patagônia Chilena e Argentina.
ABSTRACT
Abstract The Toltén river is located in the 137 years old Araucania region, Chile (38° S), and is characterized by low alterations through human interference due agriculture and towns in its surrounding basin, the presence of native fishes and salmonids, and by its lake effluent regime originated from Villarrica lake. The aim of the present study was to make a review of ecological role of the benthic inland water macroinvertebrates as preys for native fishes of the River Toltén, in order to understand their importance in the ecosystem of the river. The literature revealed that the main prey for native fishes are Chironomidae larvae, nevertheless there are not specific reports for Tolten river. The exposed results are similar with similar native species for Patagonia, and these native species would have prey for introduced salmonids, or these species would have prey competition with introduced salmonids in according to the literature descriptions for Argentinean and Chilean Patagonia.
Resumo O rio Toltén está localizado na região da Araucanía, com 137 anos de idade, Chile (38° S), e é caracterizado por baixas alterações por interferência humana devido à agricultura e cidades da bacia circundante, pela presença de salmonídeos e pelo regime de efluentes dos lagos. do lago Villarrica. O objetivo do presente estudo foi fazer uma revisão do papel ecológico dos macroinvertebrados bentônicos de águas interiores do rio Toltén, a fim de entender sua importância no ecossistema do rio. A literatura revelou que as principais presas de peixes nativos são as larvas de Chironomidae, no entanto, não há relatos específicos para o rio Tolten. Os resultados expostos são semelhantes com espécies nativas semelhantes para a Patagônia, e essas espécies nativas teriam presa por salmonídeos introduzidos, ou essas espécies teriam competição de presas com salmonídeos introduzidos de acordo com as descrições da literatura para a Patagônia Argentina e Chilena.
ABSTRACT
Plottier y Senillosa son dos localidades contiguas que forman parte del área de producción agrícola del Alto Valle de Río Negro y Neuquén, Patagonia Norte. Entre los plaguicidas más utilizados predominan las familias de neonicotinoides, carbamatos y organofosforados. El conocimiento de los niveles de estos compuestos en aguas superficiales y subterráneas se ha convertido en un tema de interés social debido a su posible impacto en el ambiente y la salud. El objetivo del presente trabajo fue determinar niveles de residuos de plaguicidas en agua subterránea utilizada para bebida en zonas rurales de Plottier y Senillosa. Se analizaron carbamatos: propoxur, carbofuran, pirimicarb, carbaril y organofosforados: clorpirifos, dimetoato, metidation, fenaminfos, triazofos, fosmet y metil azinfos, por cromatografía gaseosa (GC), en seis sitios de muestreo, durante la época de aplicación y no aplicación de insecticidas. No se detectaron residuos de los plaguicidas estudiados por el método analítico utilizado. El límite de detección fue 0,010 µg/L para organofosforados y 0,030 µg/L para carbamatos. Estos resultados indican que las buenas prácticas agrícolas aplicadas en la zona así como las características fsicoquímicas del suelo, su espesor y el contenido de materia orgánica y las propiedades fsicoquímicas de los plaguicidas estudiados son factores que contribuyen favorablemente a la calidad del agua de bebida de la población rural.
Plottier and Senillosa are two adjoining towns that belong to the agricultural production area of Upper Valley, Río Negro and Neuquén, North Patagonia. Among the most widely used pesticides, neonicotinoids, carbamates and organophosphates are predominant. The levels of these compounds in surface and groundwater have become a topic of public concern, since the possible impact on health and environment. The aim of this study was the determination of pesticide residue levels in drinking ground-water in the rural areas of Plottier and Senillosa. Carbamates: propoxur, carbofuran, pirimicarb, carbaryl and organophosphate: chlorpyrifos, dimethoate, methidathion, fenaminfos, triazophos, phosmet, azinphos methyl, were analyzed by GC in six sampling sites during insecticide application and non-application season. No pesticide residues were detected by the analytical method used. The detection limit for organophosphates was 0.010 µg/L and 0.030 µg/L for carbamates. These results indicate that good agricultural practices, the physicochemical characteristics of the soil, its thickness, the content of organic matter and the physicochemical properties of pesticides studied are factors that positively contribute to the drinking water quality in the rural population.
Subject(s)
Organophosphorus Compounds/isolation & purification , Pesticides/toxicity , Groundwater/analysis , Carbamates/isolation & purification , Carbamates/toxicity , Pesticides/analysis , Drinking Water , Chromatography, Gas/methodsABSTRACT
A total of 477 juvenile Hippocampus patagonicus recorded in 80 sampling events were detected rafting on the surface during high tide at San Antonio Bay, northern Patagonia, Argentina. If rafting juveniles drift long distances beyond their original populations, they have the potential to form new populations, which may explain the wide distribution of H. patagonicus.
