| Title |
Effect of Lugol’s Iodine Preservation on Cyanobacterial Biovolume and Estimate of Live Cell Biovolume Using Shrinkage Ratio |
| Authors |
박혜경 ( Hae-kyung Park ) ; 이현제 ( Hyeon-je Lee ) ; 이혜진 ( Hae-jin Lee ) ; 신라영 ( Ra-young Shin ) |
| DOI |
https://doi.org/10.15681/KSWE.2018.34.4.375 |
| Keywords |
Cell biovolume; Cyanobacteria; Lugol’s iodine solution; Preservation; Shrinkage |
| Abstract |
The monitoring of phytoplankton biomass and community structure is essential as a first step to control the harmful cyanobacterial blooms in freshwater systems, such as seen in rivers and lakes, due to the process of eutrophication and climate change. In order to quantify the biomass of phytoplankton with a wide range in size and shape, the measurement of cell biovolume along with cell density is required for a comprehensive review on this issue. However, most routine monitoring programs preserve the gathered phytoplankton samples before analysis using chemical additives, because of the constraint of time and the number of samples. The purpose of this study was to investigate the cell biovolume change characteristics of six cyanobacterial species, which are common bloom-causing cyanobacteria in the Nakdong River, after the preservation with Lugol’s iodine solution. All species showed a statistically significant difference after the addition of Lugol’s iodine solution compared to the live cell biovolume, and the cell biovolume decreased to the level of 34.0 ~ 56.3 % at maximum in each species after the preservation. The nonlinear regression models for determining the shrinkage ratio by a preservation period were derived by using the cell biovolume measured until 180 days preservation of each target species, and the equation to convert the cell biovolume measured after preservation for a certain period to the cell biovolume of viable cell was derived using that formula. The conversion equation derived from this study can be used to estimate the actual cell biovolume in the natural environment at the time of sampling, by using the measured biovolume after the preservation in the phytoplankton monitoring. Moreover this is expected to contribute to the final interpretation of the water quality and aquatic ecosystem impacts due to the cyanobacterial blooms. |