نوع مقاله : مقاله پژوهشی
دانش آموخته مهندسـی منابع طبیعی، گروه شـیلات، دانشکده منابع طبیعی، دانشگاه صنعتی اصفهان و عضو باشگاه پژوهشگران جوان و نخبگان دانشگاه آزاد اسلامی نراق.
عنوان مقاله [English]
Purpose of this study is to use the physicochemical parameters (DO, pH, NO3-, PO4-3, TDS, and TSI) and water quality index of IRWQI to assess the pollution and spatiotemporal impact of land use on water quality in Chaghakhor wetland in Chaharmahal-o-Bakhtiari province, Iran. Twelve stations were selected for the sampling and measurement based on a systematic non-random method. At first, index model of IRWQI was prepared in GIS environment based on average of surface and depth of qualitative parameters by interpolation functions. Results demonstrated that IRWQI index with the Pearson correlation coefficient of 0.78 and the parameters of PO4-3, NO3- and TDS with the partial correlation coefficients of -0.82, -0.64, and 0.62, respectively were caused by the sewage pollution of farmlands and residential area in the south and the west half of the wetland. Also using the GIS based spatiotemporal impacts of the land use using statistical methods showed that the highest impact on the water quality of Coghakhor Wetland is created in spring and early autumn with correlation coefficients of 0.70 and 0.59. The lowest impact is reached in the summer with correlation coefficient of less than 0.1. Maximum trophic state and the worst quality status is resulted for the surface water temperature of 10.5 to 13.5 °C and in the first half of autumn and spring. The status was shown as moderate to fairly good with values of 50 to 61 for this condition which is due to the increased agricultural activities, floods, and seasonal rainfalls. The best quality is reported for water surface temperatures of either more than 19.5 °C or less than 6 °C in the summer and the first half of winter. The Status for this condition was 70 to 82 which is due to the decreased agricultural activities, floods, and the drainage resulted from the seasonal rainfalls.