Primary production of phytoplankton and periphyton in two humic lakes of a South American wetland

Seasonal primary productivities of periphyton and phytoplankton were compared in Grande Lake (GL) and a relict oxbow lake (ROL) in winter 2006 and summer 2007. GL was free of floating plants on the sampling dates and covered over 80 and 100% of the ROL surface in winter and summer, respectively. The...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Rodríguez, Patricia Laura, Vera, María Solange, Pizarro, Haydee Norma
Publicado: 2012
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14398621_v13_n3_p281_Rodriguez
http://hdl.handle.net/20.500.12110/paper_14398621_v13_n3_p281_Rodriguez
Aporte de:
Descripción
Sumario:Seasonal primary productivities of periphyton and phytoplankton were compared in Grande Lake (GL) and a relict oxbow lake (ROL) in winter 2006 and summer 2007. GL was free of floating plants on the sampling dates and covered over 80 and 100% of the ROL surface in winter and summer, respectively. The 14C assimilation technique was used to obtain the P-E curves of phytoplankton and periphyton on artificial substrata. The periphytic maximum photosynthetic rate (P max) was higher in the ROL in winter and summer, being better adapted to low irradiances than those in the GL. Phytoplankton and periphytic algae were light-limited in the ROL in summer due to complete coverage by floating macrophytes. In summer, P max and α values for periphyton in the ROL were higher than those for phytoplankton, and were even higher than in GL. In turn, P max and α values for phytoplankton in Grande Lake were higher than those for periphyton due to improved light conditions and the presence of algae that were adapted to movement through the water column. These results suggest that the complete coverage by floating macrophytes restricted phytoplankton productivity and allowed the development of a periphytic community that was better adapted to low-light conditions. © 2012 The Japanese Society of Limnology.