Effects of Heavy Metal Pollution on Microalgae Biodiversity in a Coastal Wetland of the Pacific Ocean

Wetlands are water bodies that have long been considered ecosystems of great economic, cultural, scientific, and recreational value, the loss of which would be irreparable. In order to correlate the effects of heavy metal content in different wetlands over time with the biodiversity composition of aquatic microorganisms, several microalgae population variables were evaluated in the presence of selenium (Se), lead (Pb), cadmium (Cd), zinc (Zn), thallium (Tl) and nickel (Ni) in the water body of Paraiso Wetland (HEP) inthe Lima region, Peru, during a 2-year sampling period (2020-2021), using the Inductively Coupled Plasma (ICP) method. Samples from 12 HEP stations were analyzed. Concentration of Se in the period exceeded the Environmental Quality Standard value for this element (EQS) in 3 stations of the HEP (27%). Tl values exceeded the EQS at 1 HEP station. Pb, Cd, Zn and Ni values were below the EQS. A high population of cyanobacteria was found in the HEP, which is likely related to eutrophication and a localized presence of selenium and microcystin. Dissolved oxygen and temperature values also supported the direct relationship of these parameters with heavy metal content and eutrophication. The correlations found between microalgae, microcystin, physicochemical parameters and heavy metals content will serve as a further reference for establishing an adequate approach and technology process for remediation of contaminated water bodies.