Plankton Richness and Abundance in Several Different Hydrological Situations in Lakes Lateral to a River: A Case Study in the Mouth Zone of a Tributary into a Tropical Reservoir

Abstract

A descriptive analysis of the responses of plankton from lakes lateral to a river in its mouth zone into a tropical reservoir to water level variations is presented. Three situations were reported: 1) a comparison of species richness and diversity and of algae population abundance in prolonged drought and in periods of connection of lakes to the river, 2) the spatial distribution of abundance and richness of Rotifera species in four isolated water bodies formed by fragmentation of a lateral lake during a period of prolonged drought and in the same areas during a period of integrity as an ecosystem, 3) the variability of total zooplankton and Cladocera densities at the end of the isolation period of a lateral lake and after the recovery of connection with the river and in a year of continuous connection with the lotic ecosystem. Various idiosyncrasies were observed in connected lateral lakes, like the surface hydrologic connectivity, a primary factor in species richness modifications and a secondary controlling factor of plankton abundance. Underground hydrologic connectivity, through the river → lake water flux during the high-water period and lake → river during drought period, appears to have an important role in richness and abundance variations of planktonic populations in the lake isolated from the river.

Discrimination of hydrologic variations for spatial distribution of fish assemblage in a large subtropical temperate river

“…These results are in line with the suggestions and findings of several authors (Amoros & Bornette, 2002;dos Santos Bertoncin, Pinha, Baumgartner, & Mormul, 2019;Henry et al, 2011;Mayora, Devercelli, & Giri, 2013), meaning that the homogenizing effect of the flood pulse is not a general rule and must be adjusted to the kind of situation, aquatic organism and river. For example, while zooplankton beta diversity and environmental heterogeneity decrease during flooding (Bozelli, 1992;Bozelli, Thomaz, Padial, Lopes, & Bini, 2015), fish dispersal is likely to increases and fish assemblage homogenization may occurs later, during low water phases.…”

Intra and inter-annual structure of zooplankton communities in floodplain lakes: a long-term ecological research study

“…Studies performed in South American floodplain systems have found higher abundances of some zooplanktonic species during dry periods or limnophase (Brandorff & Andrade 1978, Saunders & Lewis Jr. 1989, Paggi & De Paggi 1990, Lansac-Tôha et al 1993, Lima et al 1998, Rossa & Bonecker 2003, De Paggi & Paggi 2007Henry et al 2011), when the hydrodynamic conditions were more stable, thus promoting primary productivity which supports large populations of zooplanktonic organisms due to higher water residence time (Baranyi et al 2002). In contrast, during potamophase, we observed a dilution effect in which organisms were more dispersed in the water column (Bozelli 2000, Lansac-Tôha et al 2009).…”

Spatiotemporal dynamics of C and N isotopic signature of zooplankton: a seasonal study on a man-made lake in the Mediterranean region

“…The biodiversity and conservation of such reservoirs are particularly sensitive to climate change (Moss et al, 2009) and are considered as stressed environments (Leira and Cantonati, 2008 and references therein;Naselli-Flores, 2003;Henry et al, 2011;Perbiche-Neves et al, 2011). Compared with natural lakes, artificial waterbodies are subject to severe fluctuations in the water level from seasonal and interannual climatic variations, as well as abstraction for irrigation, hydropower and drinking water.…”