Abstract

AGUILAR ZURITA, Alex  and  RODRIGUEZ, Patricia. Relationship between phytoplankton and bacterioplankton production in vegetated humic shallow lakes. Ecol. austral [online]. 2016, vol.26, n.3, pp.305-310. ISSN 1667-782X.

In this study, we show that depth-integrated pelagic primary production (PP) can exceed bacterioplankton production (BP) in vegetated humic shallow lakes, giving as a result an autotrophic water column, despite light restrictions and availability of organic carbon for lake bacteria. Intuitively, these conditions should favor the development of a heterotrophic water column. Instead, during our survey, BP represented between 1.3 to 5% of PP most of the time. Only once, during late summer, BP was ~71% of PP. Although we cannot conclude about the mechanisms behind the observed results, previous surveys and experimentation in the wetland allow us to hypothesize that autotrophic conditions were favored by: i) the shallow nature of the lakes, which compensates for light attenuation by organic matter when integrating production in the water column, ii) the presence of anaerobic anoxygenic photosynthetic bacteria below the macrophyte cover, and iii) high predation rates on bacterioplankton by heterotrophic flagellates below the floating plants.

Keywords : Primary production; floating plants.

        · abstract in Spanish     · text in English     · English ( pdf )