Argentina 4 Clear shallow lakes 4 Periphyton 4 Phytoplankton 4 Turbid shallow lakes algae 4 lake ecosystem 4 light availability 4 periphyton 4 phytoplankton 4 turbidity 4 Bacillariophyta 2 Chlorophyta 2 Cyanobacteria 2 HPLC 2 Pampas 2 Pigment composition 2 Primary production 2 Sierras Pampeanas 2 algal community 2 carbon balance 2 community structure 2 light effect 2 limiting factor 2 liquid chromatography 2 metabolism 2 pigment 2 primary production 2 shallow water 2