Spatial Variability Assessment of Water Quality in Anzali Wetland Using Kriging

In this study, selected statistical methods (Pearson correlation and Geostatistics) were used to determine the most important water quality parameters and their Spatial variability in different parts of Anzali wetland. After a random sampling of water in 9 different points of wetland and 11 rivers that flow into Anzali Wetland, the most important parameters were measured. Pearson correlation results showed that DO have negative correlation with BOD ,COD, T-N, T-P and turbidity. To use the ordinary Kriging in Spatial variability of parameters, normal distribution of data was first determined using Kolmogorov-Smirnov test and after Semivariogram calculation, circular, spherical, exponential and Gaussian models were fitted to each water quality parameters and Cross-Validation was used for validation. The best model for EC ,pH, COD, DO, BOD, turbidity, T-P and for T-N were exponential and Gaussian. The results revealed a high estimation accuracy for pH, T-N, and T-P. In addition, Kringing application reveals Shijan and Abkenar have the worst and the best water quality, respectively and water quality decreases from west to east part of the wetland.