Zooplankton community dynamics and environmental factors in Lake Ozeros (Greece)

Abstract

A one-year investigation of the zooplankton community composition and dynamics in Lake Οzeros (western Greece) revealed 25 invertebrate species (16 rotifers, three copepods, five cladocerans and one mollusc larva). The mean zooplankton abundance fluctuated between 59.4 to 818 ind l -1 , with maximum values in spring. The species composition and seasonal variation do not differentiate Lake Ozeros from the nearby lakes. The presence of the dominant calanoid copepod Eudiaptomus drieschi and some of the rotifer species recorded are characteristic of either oligo-or eutrophic lakes. According to the trophic state index (TSI), Lake Ozeros is a meso-eutrophic ecosystem, in which the eutrophic character is possibly the result of the high phosphorus load (being 28.9% higher in comparison to previous decades), which is due to the surrounding agricultural cultivations and mainly the pig-raising activities. In contrast, the concentrations of ΝΟ 3 , ΝΟ 2 and NH 4 have considerably decreased possibly due to the termination of tobacco cultivations around the lake during the last years. The novel information on the abiotic and especially the biotic elements of Lake Ozeros provided by this study can contribute to the effective management of this aquatic ecosystem in the future.

Diversity measures in macroinvertebrate and zooplankton communities related to the trophic status of subtropical reservoirs: Contradictory or complementary responses?

“…In natural environments, a relationship between the effects of small changes in the trophic status of the zooplankton community has been observed, especially when considering the group of rotifers, which includes species that are tolerant to different trophic conditions (Chalkia and Kehayias, 2013;May and O'Hare, 2005). In contrast, a high abundance of larger zooplankton species (e.g., cladocerans) has been reported in ecosystems that reflect reference conditions, bearing in mind that a greater availability of refuge areas occurs in such environments, which reduces the pressure by foraging zooplanctivorous fish (Moss et al, 2003).…”

Species diversity and community structure of zooplankton in threedifferent types of water body within the Sakarya River Basin, Turkey

“…Zooplankton is a very important component of the ecological quality of lakes (Moss et al, 2003), being a critical link between phytoplankton and higher consumers (Chalkia and Kehayias, 2013). Some biotic and abiotic parameters, such as temperature, habitat differences, and the presence or absence of fish and macrophytes, may affect the richness and composition of zooplankton species (Jeppesen et al, 2000;Muirhead et al, 2006;Kaya et al, 2010).…”

Alteration of the feeding behavior of an omnivorous fish, Scardinius acarnanicus (Actinopterygii: Cypriniformes: Cyprinidae), in the presence of fishing lights

“…Lake Ozeros is a karstic lake covering an area of 10.1 km 2 and having a catchment area of 59 km 2 . It is a typical shallow Mediterranean lake with a maximum depth of 5.6 m. The trophic state of the lake can be characterized as mesotrophic (Chalkia and Kehayias 2013). Finally, Lake Amvrakia is the second largest lake in the area, covering an area of 14.5 km 2 and having a catchment area of 177 km 2 , with a maximum depth of about 50 m. Lake Amvrakia can be characterized as mesotrophic (Chalkia et al 2012).…”