Publications (2)3.57 Total impact
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Article: Comparison of morpho-functional phytoplankton classifications in human-impacted shallow lakes with different stable states
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ABSTRACT: The morpho-functional classifications of phytoplankton have been recently proposed as useful tools in the aquatic biomonitoring. In this study, we compared three different classifications in a range of different environmental conditions, a set of six shallow lakes with different stable states. The studied lakes are located in the Pampa Plain from Argentina, a region highly impacted as a consequence of the human activities. Among the selected lakes, three are in a turbid state, two of which have high phytoplankton abundances (phytoplankton-turbid), and one shows a high concentration of suspended inorganic matter (inorganic-turbid). Two lakes are clear and profusely colonized by submerged plants (clear-vegetated). Only one lake shows a typical alternative steady-state behavior, shifting turbid periods of high phytoplank-ton biomass with periods of more transparency and development of submerged macrophytes. We com-pared the three morpho-functional classifications applied by means of multivariate analyses in order to explore how much the variance of the biomass of the phytoplankton functional groups (for each functional classification) was explained by the environmental variables. The analyses performed showed a clear separation of the human-impacted turbid lakes from the clear-vegetated lakes. The advantages and disad-vantages of the different morpho-functional classifi-cations are discussed, concluding that the functional approach is adequate to analyze the phytoplankton communities in aquatic systems subjected to anthro-pogenic influence and for monitoring them.Hydrobiologia 01/2012; · 1.78 Impact Factor -
Article: Phytoplankton and primary production in clear-vegetated, inorganic-turbid, and algal-turbid shallow lakes from the pampa plain (Argentina)
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ABSTRACT: Shallow lakes often alternate between two possible states: one clear with submerged macrophytes, and another one turbid, dominated by phytoplankton. A third type of shallow lakes, the inorganic turbid, result from high contents of suspended inorganic material, and is characterized by low phytoplankton biomass and macrophytes absence. In our survey, the structure and photosynthetic properties (based on 14C method) of phytoplankton were related to environmental conditions in these three types of lakes in the Pampa Plain. The underwater light climate was characterized. Clear-vegetated lakes were more transparent (K d 4.5–7.7m−1), had high DOC concentrations (>45mgl−1), low phytoplankton Chl a (1.6–2.7μgl−1) dominated by nanoflagellates. Phytoplankton productivity and photosynthetic efficiency (α~0.03mgCmgChla −1h−1W−1m2) were relatively low. Inorganic-turbid lakes showed highest K d values (59.8–61.4m−1), lowest phytoplankton densities (dominated by Bacillariophyta), and Chl a ranged from 14.6 to 18.3μgl−1. Phytoplankton-turbid lakes showed, in general, high K d (4.9–58.5m−1) due to their high phytoplankton abundances. These lakes exhibited the highest Chl a values (14.2–125.7μgl−1), and the highest productivities and efficiencies (maximum 0.56mgCmgChla −1h−1W−1m2). Autotrophic picoplankton abundance, dominated by ficocianine-rich picocyanobacteria, differed among the shallow lakes independently of their type (0.086×105–41.7×105cells ml−1). This article provides a complete characterization of phytoplankton structure (all size fractions), and primary production of the three types of lakes from the Pampa Plain, one of the richest areas in shallow lakes from South America.Hydrobiologia 04/2009; 624(1):45-60. · 1.78 Impact Factor
