Divergent dynamics of microbial components in two temperate shallow lakes with contrasting steady states in the Southern Hemisphere

FERMANI, PAULINA; LAGOMARSINO, LEONARDO; TORREMORELL ANA; ESCARAY, ROBERTO; BUSTINGORRY, JOSÉ; LLAMES, M.E.; PEREZ, G.L.; ZAGARESE, H.E.; MATALONI, G.

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2021 vol. 93 p. 1 - 26

0001-3765

Factors that affect abundances of organisms in water bodies are influencedby extrinsic and intrinsic drivers that operate from outside and within a system. A hightemporal coherence in the dynamics of abiotic parameters and biological communitiesamong neighboring lakes evidences a strong extrinsic control operating similarly acrosslakes, and allows for prediction of ecosystems evolution in the context of global changeand intensive land use. The Pampa region (Argentina) encompasses many shallowlakes submitted to different degrees of anthropic influence and showing contrastingalternative states. We studied an eutrophic clear and a hypertrophic turbid shallow lakeduring an annual cycle in order to evaluate whether they responded similarly to extrinsicfactors or these were overridden by the effects of the steady state of each lake. Physicaland chemical variables were highly coherent between both lakes, but accounted littlefor the large disparities among abundances and dynamics of microorganisms. Whilecommunities from the clear lake responded to a combination of extrinsic and intrinsicfactors, the turbid lake showed a state less prone to be affected by climatic effects. Wehypothesize that clear lakes would perform better as sentinels of climate change in thePampa wetland.