Algae as indicator to assess trophic status in Dokan Lake, Kurdistan region of Iraq

الملخص EN

This survey was related to study the algal status of Dokan Lake to evaluate the trophic status of lake productivity.

Data for application of phytoplankton compound quotient (PCQ) equations and dominant genus scores were collected from previous studies for Dokan lake periods during 1980, 2000 and 2016.

A total of 101,61and 135 respectively algal taxa which have into 6 taxonomic groups were determined.

From phytoplankton content in this survey, it seems that among diatom species Cyclotella ocellata, Stephanodiscus astrea, Nitzschia spp and Navicula spp were the most common taxa in this survey.

On the other side, non-diatom species in this search were to be dominanated by Pyrophyta in especially in warm months such as Ceratium hirundinella and Peridium cinctum.

Ecological status of the Dokan Lake was mesotrophic in 1980 and 2000 while in 2016 was hypertrophic according to phytoplankton compound quotient (PCQ=4.5, 2.8 and 8.0) respectively.

As a result of dominant genus scores (3.8, 4.2 and 6.5), the lake has a mesotrophic character according to trophic level in 1980 and 2000, and was meso-eutrophic in 2016.

In addition, the water quality of Dokan Lake was moderate in 1980 and 2000 and moderate polluted in 2016.