Determination Zooplankton Spatial, Temporal and Population Structure Changes of the Bukan Dam Using Geo-statistics

This study was performed to investigate the spatial and temporal changes of the zooplankton population in the Bukan reservoir and to map these variations for agricultural and fisheries exploitation.

The samples were taken monthly from eight sampling sites during 2015. The samples were filtered through a 55-micron mesh size filter, fixed by 4% formalin and enumerated by an inverted microscope. Geo-statistics interpolation method in GIS (GS+ software) was used to reveal spatial changes of zooplankton and to estimate it in non-sampled points. The cross validation method was used to evaluate and compare the geostatistical methods.

Spherical model fitness on the empirical semi-variogram of zooplankton density in the winter provided the results that indicated the radius of semi- variogram effect is 7280 m. The correlation coefficient of the fitted model was 0.995. The Kriging method with error of -53.42 was selected as a suitable model for spatial assessment of zooplankton density.

Most of the zooplankton population is in the summer and the lowest was seen in the spring. The maximum number of zooplanktons at the beginning of the Bukan dam which regularly reduced towards end of the dam.