Inland water microcrustacean assemblages in an altitudinal gradient in Aysen region (46° S, Patagonia Chile)

Abstract

The Chilean Patagonia has numerous kinds of inland water ecosystems such as lakes, ponds, wetlands and rivers that have been poorly studied due to access difficulties. This study was carried out in Aysen region, in southern Chile, and it included different kinds of water bodies such as rivers, streams, ponds, lagoons and lakes distributed along an altitudinal gradient at 46° S. It was found a low species number, essentially cladocerans, copepods and amphipods. A null model was applied in order to determine the existence of regulator factors of species associations, and the results revealed that they are not random. The patterns would be influenced by geographical and limnological characteristics of the studied sites. Our results would agree with regional studies on habitat heterogeneity such as in Torres del Paine National Park and other zones in Tierra del Fuego island.Keywords: microcrustaceans, Boeckella, Hyalella, null models, Patagonia Crustáceos zooplâncton de águas continentais litorales na gradiente de altitude na região de Aysén (46 ° S, Patagônia Chile) ResumoA Patagônia chilena apresenta numerosos tipos de ecossistemas aquáticos, como lagos, lagoas, pântanos e rios, os quais tem sido pouco estudados devido a dificuldades de acesso. Este estudo foi feito na região de Aysén, no sul do Chile, e inclui diferentes tipos de corpos d'água, tais como rios, córregos, lagos, lagoas e lagos distribuídos ao longo de um gradiente de altitude a 46° S. Constatou-se baixo número de espécies que inclui, essencialmente, cladóceros, copépodos e anfípodos. Um modelo nulo foi aplicado para determinar a existência de fatores reguladores das associações de espécies os resultados indicam que estes não são aleatórios. Os padrões poderiam ser influenciados pelas características geográficas e limnológicas do locais estudados. Os resultados expostos concordariam com estudos regionais sobre com habitats heterogeneidade como Torres del Paine Parque Nacional e outras zonas na ilha de Tierra del Fuego.

Composition of cladoceran dormant stages in intermittent ponds with different hydroperiod lengths

“…The study area is located in a 1000 m-high region. High altitude (Ormerod et al 1994;Los Rı´os-Escalante et al 2014) is generally associated with low temperatures (Santangelo 2009), which directly accounts for reductions in invertebrate richness, including in southern Brazil wetlands (Stenert and Maltchik 2007;Stenert et al 2008). Furthermore, ponds were isolated by a minimum distance of 1 km.…”

“…Sampled material was immediately preserved with 80% ethanol. Cladoceran specimens were identified to species level, according to Lopretto and Tell (1995) and Elmoor-Loureiro (1997). We deposited the specimens in the aquatic invertebrate collection of the Laboratory of Ecology and Conservation of Aquatic Ecosystems of UNISINOS.…”