Population Dynamics of Copepods as Influenced by Heavy Metals in Khanki Headworks, Pakistan

Abstract

Copepods grow in diverse freshwater habitats, totaling around 2,814 species. As foremost zooplankton, they lead biomass and are pivotal in aquatic ecosystems. The ever-increasing issue of heavy metals contamination affects organisms differently. Copepods, with their broad geographic range, can be valuable bio monitors for metal growth. Objective: To evaluate the effects of heavy metals and fish diversity on the population dynamics of copepods in Khanki Headworks, Pakistan. Methods: For the analysis of heavy metals month wise water samples (1000 ml) from four selected sites were collected for one year (February 2021 to January 2022). Atomic Absorption Spectrophotometry was employed for the analysis of heavy metals. Month wise copepods samples were collected with planktonic net (mesh size: 37µm). Results: In total, seven species and four genera of copepods were identified. Mesocyclops edax was the most dominant copepod species. Three heavy metals zinc (Zn), arsenic (As) and nickel (Ni) were estimated in following order of concentrations Zn> Ni> As. Conclusions: Current investigation revealed that heavy metals generally govern the population dynamics of copepods.