No abstract

Reservoirs are vital and necessary resources of potable water. Different sectors such as agriculture, industry and fishery are dependent on these resources which need high quality water. Water quality is mainly evaluated using different parameters such as pH, temperature and turbidity which are easily measured. Also there are some more complicated parameters such as eutrophication degree of a water body. This study was accomplished to investigate the trophic state of Ecbatan reservoir in dry and wet seasons. Water sampling was accomplished in July and January to compare the trophic state of the reservoir in two critical situation of a hydrologic dry year. 15 stations were selected in different points of the reservoir. Different parameters of water quality were measured such as temperature, pH, Secchi Disk (SD), Total Nitrate (TN), Total Phosphate (TP) and chlorophyll-a (chla). The trophic state was estimated for all stations using Carlson index. Results of the study show that trophic state of the lake is mild mesotrophic in July and acute mesotrophic in January. Also Phosphorous is the limiting nutrient in this reservoir. This research showed that eutrophication is a serious problem in Ecbatan reservoir and managerial strategies are required to prevent water quality deterioration.

In this study, 9 remaining water components of Madian River in the Baraftab were considered. Autoregressive Integrated Moving Average modeling techniques are considered appropriate in creating and predicting components. SO42–, Na + and SAR show a declining fashion despite the different properties of brilliant water, which show an increasing lightness. However, practicing a delay to the position of the style desk was sure that the time group was ready for painting. Similarly, the time group study suggests that there is an unfamiliar location increase mode for all components except SO42–, Na + , and SAR. EC, Cl–, Ca2 + , Mg2 + and HCO3– show an increasing style, which is suggested to reduce the prominent water within the area. Depend on the sphere revisions, the extreme successful and relative population density, rising the use of artificial frameworks, departure city effluents and mainstream of rural manure in conservative method via streams, inopportune plans of burial litters, dispersal of nonsenses and disorders in floor waters and watercourses which later influx via streams are taken into deliberation because the important reasons of water brilliant worsening. Agronomic effluents and livestock are different causes that pollute floor water. Also, the water hazard outstanding worsening is rising because of extreme public boom with inside the area and green changes are energetic with inside the zone to exclude you larger ecological devastation.

Background and purpose: The study aimed to investigate the trophic state of Ekbatan Dam Lake. In the current research, the quality of water behind the dam was studied during the months July and January in order to compare the trophic state and zonation of the reservoir in two different seasons (dry and wet). Materials and Methods: 15 stations were selected in different points of Ekbatan Dam Lake and sampling was accomplished in July and January. To determine the rate of eutrophication in the reservoir, 30 samples (15 in July and 15 in January) were taken from the reservoir. In this study, secchi disk, nitrate, phosphate and chlorophyll-A were measured. Then, using Carlson's Trophic State Index, the rate of eutrophication was estimated for all points. Also, using GIS zoning of water quality parameters, TSI (Trophic State Index) value was evaluated in two different seasons. Results:The findings of the current study showed that TSI varied between 35.7 and 50.7 in different stations of the lake in July. At the same time, it was documented to vary between 55.13 and 58.6 at different points in January. Also, the results revealed that the trophic state of the lake is oligotrophic to eutrophic in different stations in July while it was eutrophic for all points in January. Conclusion: Based on the estimated values of this index, the stations located at the entrance of the lake showed more eutrophic situation in July. Also, phosphorous was revealed to be the limiting nutrient in this system. The current research showed that eutrophication is a serious problem in Ekbatan reservoir.

Water deficit problem originates from two factors: population increase and water pollution. However, studying and forecasting the quality of water are necessary to avoid serious problems in future through managerial works. In present study, using time series modeling, the quality of Madian Rood River is studied at Baraftab station using time series analysis. Nine parameters of water quality are studied such as: TDS, EC, HCO 3-, Cl-, SO 4 2+ , Ca 2+ , Mg 2+ , Na + and SAR. Investigation of observed time series shows that there is a common increasing trend for all parameters unless Na + and SAR. The order of models for each parameter was determined using Auto Correlation Function (ACF) and Partial Auto Correlation Function (PACF) of time series. The ARIMA model was used to generate and forecast the quality of stream flows. Akaike Information Criterion (AIC), Determination Coefficient (R 2), Root Mean Square Error (RMSE) and (Volume Error in Percent (VE %) criteria were referred to evaluate the generation and validation results. The Results show that time series modeling is quite capable of water quality forecasting. For the majority of forecasts, the value of R 2 was greater than 0.6 between predicted and observed values.