Do water levels control zooplankton secondary production in Neotropical floodplain lakes?
Dias, Juliana D.; Miracle , Maria R.; Bonecker, Claudia C.
published: Apr 1, 2017
published online: Mar 2, 2017
manuscript accepted: Feb 17, 2017
manuscript received: Oct 30, 2015
ArtNo. ESP141019001004, Price: 29.00 €
Abstract Secondary production is an important measure of the functional role of heterotrophic organisms at different trophic levels in an ecosystem. We quantified the production of zooplankton groups during low and high water periods in two shallow lakes on a Neotropical floodplain. Environmental conditions varied markedly between the lakes and between periods. The production of rotifers was greater in the isolated lake due to higher values of chlorophyll-a and lower flushing. In contrast, the production of cladocerans was higher in the connected lake, where fish predation pressure was lower. Diaptomids and cyclopoids exhibited no significant differences in secondary production between the lakes. Water levels influenced the secondary production of the zooplankton groups. Copepods always presented higher production values, but rotifers had greater turnover rates during low water periods. Organisms with smaller body sizes, higher growth rates, and shorter life cycles, such as rotifers, are more rapidly affected by increasing water inflow. Zooplankton groups played different roles in the flow of energy and biomass in the floodplain, being dependent on the trophic dynamics of the ecosystem, which was in turn shaped by environmental heterogeneity and seasonal changes.