Trace Elements in Plankton, Benthic Organisms, and Forage Fish of Lake Moreno, Northern Patagonia, Argentina

Abstract

The Northern Patagonian Andean range shared by Chile and Argentina has numerous glacial oligotrophic lakes protected in a series of National Parks. Recent baseline surveys indicated that concentrations in muscle and liver tissues from various fish species from across Nahuel Huapi and Los Alerces National Parks in Argentina were comparable or higher than similar fish species from other parts of the world. As a result, Lake Moreno, in Nahuel Huapi National Park, was chosen to investigate multiple element sinks, trends, and transfer in a representative Patagonia aquatic food web. The metals and metalloids Ag, As, Ba, Br, Cs, Co, Cr, Fe, Hg, K, Na, Rb, Se, and Zn were analyzed in three size plankton fractions, submerged macrophytes, biofilm, insect larvae, amphipods, decapods, gastropods (snails), annelids (earthworms), and forage fish. Except for nanoplankton (10-53 μm; small-celled algae, rotifers) and microplankton (53-200 μm; larger algae, ciliates, zooplankton nauplii), which share elemental compositional similarities, each taxon category had its own distinctive compositional pattern, revealed by principal component analysis. Nano-and microplankton tend to be relatively elevated in some metals, including As, Co, Cr, Fe, Hg, Zn, and Rb, followed by biofilm. Shredder-scrapper Trichoptera (caddisflies) have higher concentration of most of the studied elements than other insect larvae taxa, especially carnivorous Odonata (Anisoptera, dragonflies), which were associated with lower elemental contents. Those trends point to an overall tendency for biodiminishing element concentrations with trophic level in the benthos of Lake Moreno.

Differential mercury transfer in the aquatic food web of a double basined lake associated with selenium and habitat

“…Seasonal and location-specific analyses for individual elements were reported previously, and the consistency of the data supports the grouping of species-specific data points across seasons and sites within Lake Moreno (Arcagni et al, 2013;Arribére et al, 2008Arribére et al, , 2010aRizzo et al, 2011). The only significant differences we had observed were on how carbon was transferred through the food web and differences in baseline δ 15 N values, which were attributed to differences in pelagic vs. littoral habitat availability, and differences in anthropogenic inputs between the basins, respectively (Arcagni et al, 2013;Queimaliños et al, 2012).…”

Non-proportional bioaccumulation of trace metals and metalloids in the planktonic food web of two Singapore coastal marine inlets with contrasting water residence times

“…Pacific Ocean,Twining et al (2011) detected phytoplankton concentrations of Mn, Fe, Co, Ni, and Zn of several orders of magnitude lower than observed in the present study. In a protected glacial lake in the Patagonia, Argentina,Arribére et al (2010) reported As, Co, and Fe values one order of magnitude lower than those reported in the present study. Moreover, in the South China Sea and in Shimizu Port (Japan),Ho et al (2007) andSakata et al (2012), respectively, also detected ca.…”

Trace element accumulation in lotic dragonfly nymphs: Genus matters

“…The taxonomic level analyzed in studies of trace element accumulation in odonates varies extensively. Some studies analyzed organisms composited by order [ 77 , 78 ] or suborder [ 5 , 79 , 80 ]. Others have composited by family, sometimes with comparisons between families [ 81 ], but others with only a single anisopteran family [ 7 , 30 , 82 ].…”