Diatomeas in present environments

Group Leader

Nora Maidana Dra. Nora I. Maidana
Investigador Independiente (CONICET)                                  

On this line of work, we developed two sub groups, each one in the frame of one or more projects.

1.Diatom biodiversity in high mountain environments in the NOA

Aquatic ecosystems (lentic and lotic) in high mountain regions host a diverse diatom flora characterized by a high percentage of endemic species, and adaptations/specializations as a result of isolation and extreme environmental conditions to which they are exposed. Comparatively, despite its importance and fragility, high aquatic environments have been little studied in South America, with only a few studies in Colombia and Bolivia. In several Argentinean provinces the development of extractive mineral activities has remarkably increased in the last years. For this reason, it is vital to perform baseline studies to determine the composition of natural communities of diatoms, prior to commencement of mining activities and thus have a baseline for subsequent environmental monitoring.

Our objectives are:

  • Increase the knowledge of high Andean diatom biodiversity in lentic and lotic aquatic environments, identifying the representative taxa and their relationship to the environment.
  • Study the spatial and seasonal distribution of epipelic diatom assemblages in each of the studied sites and relate them to the physical, chemical and biological parameters.

2.Diatom biodiversity in Patagonia, Argentina

Among the various tools used for paleoenvironmental reconstructions, diatoms are among the leading proxies because their assemblages are modified in response to changing environmental conditions, and fossil assemblages recovered from the sedimentological record contained in these water bodies become a valuable archive that allows the reconstruction of past environmental conditions. Between 2008 and 2012, under the framework of the ” Southern Patagonia Interdisciplinary Project ” (PICT / Redes 2006 No. 02338) we began to develop a diatom based training set, with data obtained from 41 southern Patagonia lakes (Argentina, 48-52 ° S).

Our objectives are:

  • Substantially increase the current knowledge of the biodiversity of diatoms in the Patagonia Argentina.
  • Complete the existing database of biodiversity of diatoms, their ecological requirements and its current geographical distribution in lentic water bodies of the southern province of Santa Cruz, between 49º and 52º S.
  • Relate the distribution of diatoms with the physical, chemical and climatic data of the habitats they occupy (training set)
  • Develop transfer functions applicable to paleoenvironmental reconstructions