In this study, the cultivation of two microalgal species using anaerobic digestate as a nutrient medium was investigated. Several pretreatment methods were applied to the anaerobic digestate including hydrogen peroxide treatment, filtration using polyester filter bags, and supernatant extraction; the latter proved to be the simplest and most effective method in reducing the turbidity and COD of...

Some freshwater phytoplankton species are plastic in their morphology, physiological characteristics, genetic structure, and biochemical composition. These characteristics of planktonic algae vary considerably under different environmental conditions in aquatic ecosystems. Algae such as Staurastrum sometimes lose their spiny form, and large multi-f ilament ‘f lakes’ of Aphanizomenon grows as si...

Deep-water hermit crabs of the family Parapaguridae can be abundant (up to 20 kg or 1000 hermit crab individuals per haul) in the trawl bycatch collected during South African demersal abundance research surveys. Until recently, only two parapagurid species had been recognized in the bycatch; Parapagurus bouvieri Stebbing, 1910, and Sympagurus dimorphus (Studer, 1883). Detailed examination of nu...

It is known that the zooplankter Daphnia induces colonies in the alga Scenedesmus. As Daphnia grazes on Scenedesmus, it has been postulated that colony formation represents an algal defense mechanism. This induction of Scenedesmus coenobia/colonies by Daphnia could be associated with a substance exuded by the animals that acts as a specific infochemical (kairomone) for Scenedesmus. However, the...