Rivers are the most important landforms on the ground whose analysis is known as a useful tool in tectonic surveys in several thousands to two million years ago. The Ghezel Ozan River, the longest river system in the country, has responded to tectonic deformation thoroughly. Detection and characterization of geomorphic anomalies in the Ghezel Ozan River and correlation with structures can specify the role of structures in making active deformations. The intense and sudden deflection in the river course, the abnormal changes in the river sinuosity and knick points upon longitudinal profile of the river are the geomorphic anomalies connected to the structures. Deflection of the river course and abnormal changes in the river sinuosity are identified on the satellite images and approved through field observations. Knick points are specified upon longitudinal profiles of the river and the effects of lithology are surveyed in making of them٫ so that only knick points are considered which are produced by structures. Longitudinal profiles of the river have been obtained from digital elevation model. Above mentioned anomalies then have been correlated with structures extracted from geology maps and in this manner structures effective in making geomorphic anomalies have been identified. The study region is located in Sanandaj–Sirjan, Centeral Iran and Western Alborz zones. Around the Ghezel Ozan River, marl, sandstone, siltstone, limestone, tuff, agglomerate and volcanic rocks are extremely exposed. These rocks belong to Qom, Upper Red, Lower Red and karaj formations. Deflection of the Ghezel Ozan River is surveyed in the regions of Kuh-e-Palangi, Jelovdarlou, Cham and Yengejeh. Abnormal changes in river sinuosity is studied in regions of Jomaelou, Gol gheshlagh, Armoutlou, Kuh-e-Qaravol, Ghaflankuh and Kuh-e-Pajdar. In the regions of Sharif Abad, Iemir, Kuh-e-Qaravol and Kuh-e-Pajdar, knick points are specified upon longitudinal profile of the Ghezel Ozan River. The obtained results show that folds with trends of NW–SE and NE–SW have the highest influence on deflection of the course of the Ghezel Ozan River. The other geomorphic anomalies produced by faults with trends of NW–SE, NE–SW, N-S and E-W especially in instances that faults with trends of NW–SE and NE–SW have intersected. Thus, the most active structural trends in around of the Ghezel Ozan River are trends of NW–SE, NE–SW, N-S and E-W which correlate with trends of fractures in basement of Iran. In this way active folds and faults are identified in the area.

1 Introduction The Chaos Theory was first used in the meteorology by Edward Lorenz in 1965 that turned it into a science (Kram, 2010). CHAOS means turmoil and disorder, and the synonym is turbulence in mechanics,; the term implies the absence of any structure or order. Usually, in everyday conversations, chaos and turmoil are signs of disorder and ineffectiveness, and have a negative aspect (Sayed Javadin, 2009). Geomorphologists describe the past and present trends as an essential principle and predict the future of processes. They, thus, understand the nature and the speed of change. Chaos means the order of a disorder The presence of new alluvial fans at the base of old alluvial fans, Galli, unbalanced landforms, etc. in the Ghezel Ozan basin indicates a change in the level base and active tectonics in the area. The main reason for the creation of a unbalance is the change in the base level, which they reflected as recession erosion in rivers and canals. Capture and deviation phenomena of glacial lakes discharge are due to variations and imbalances in the basin. The basis of the study of the Ghezel Ozen basin in a chaotic model is linear and surface erosion and a combination of both in different regions. The basin area of Ghezel Ozan is among the Caspian Sea basins, which originates from the heights of the Chehelcheshmeh Cheshmeh Kordestan, and after entering the Bijar Geonrouns, through its tributaries Mahanhan, Rajain, Hashtjin enters Tarom and flows into the lake of Manjil dam, and eventually after joining Shahrud to Sefidrud enter the Caspian Sea. This basin is located in Kurdistan, Zanjan, East Azarbaijan, Ardebil, Hamedan and a small part of the provinces of Qazvin, West Azerbaijan, and Gilan. 2 Materials and Methods This research, which is based on library and field studies, attempts to study the chaotic behavior of geomorphologic processes in the Ghezel Ozan basin. For this purpose, changes in the basal level, captivity and river diversion, the sudden collapse of congestion, intermittent floating cones, hydro-geomorphologic cells, geomorphologic dominoes, salt domes and decreasing erosion coefficients in Ghezel Ozan sub-basins have been studied. To investigate the chaotic dimension of the target area, DEM of 30 * 30m of the region, we extracted our data from SRTEM satellite site. Then we removed the contour layer of the part from the DEM using Arc GIS software. Also, using 1: 50000 topographic maps of the study area, the rivers were extracted and digitize in ArcGIS software, and their pattern was analyzed. The lithology layer was digitized using geology maps of 1: 100, 000 and 1: 250, 000, and the network of drains was extracted with the help of DEM of the region. 3 Results and Discussion Equilibrium is one of the words that have a special meaning in the chaos perspective. Chaos regards balance as an order in disorder. In the geomorphological equilibrium, external processes affect both the internal and the combination of both. The base of a river and its branches are one of the main parameters without which the analysis of drainage basins is impossible. The unity of the Ghezelan basin at the beginning of the Quaternary meant the existence of different geonerons., They were an independent gathering place of matter and energy that were formerly local base level. . Such standards are the basis of localization in the current situation through traceable sediment traces. The numerous profiles plotted perpendicular to the Ghezelowzan River indicates a sudden downturn in the valley of rivers. The effects of local changes in Geonroun Bijar and Zanjanrood were detected through aggregate levels and alluvial plains. 4 Conclusion The results show that the effects of changes in the baseline levels in Geonroun Bijar and Zanjanrood were reflected as congestion levels. The same changes have led to the capture and diversion of the QalaehChay, Mehrabad and Anguran Chay. The difference in the base levels in Geonroun Tarom on the two sides of the Ghezelowzan has leftover ten overlapping faces. The Geonrountic network of the Ghezel Ozen basin has been affected by several factors; their accumulation referred to as the cell. Distribution of lithological and tectonic cells has caused erosion of the line or line at the river level. The energy of the changes in the base level in the outflow basin transferred from the highest river rank, such as dominoes, to the status of the first rivers. In addition to excavation and excavation of dams, Ghezel Ozan domes, exploring and digging the rivers of the Ghezel Ozan Basin have played a significant role. The fractal dimension between 1 and 2 of most sub-basins is a line-level fractal. The fractal dimension above 2 in the rest of the sub-basins indicated the surface of the fractal. The mean erosion coefficient of recoil at the ranks 1 of the Zanjan and Tarom rivers indicates the discharge of matter and energy of the Tarom geonroun in the line.

The Ghezel Ozan basin in an area of 50000 KM2 is in the northwest of Iran. Recognition of variables like captivity and deviation of rivers, erosion and compact surfaces, the affects of old lakes by the reflected affects on 1: 50000 scaled topographic maps of the region, are some of the points which is tried to find out the changes of Quaternary of the basin. Although Ghezel Ozan basin is ended to Caspian sea as an open basin, the geomorphologic and topographic evidences show that this basin became independent between two basins of Ghom and Orumiye after Pasadenian moves and also was multiple closed sub basins which the waters were moved to the central pits in each surface such as Bijar, Zanjan, Tarom, Yangi Kand and Miyane. The size of some of these pits is such huge so that could be visible in topographic maps by water network and marl sediments of their bed. On the other hand, some are very small and limited which follow the local topographic position or has shaped under the influence of the main processes of the time and has been destroyed by changes. The past topographic situation and the main processes of glaciers in cold Quaternary, has made different lakes near Ghale Chay River. Pari Lake is an obvious example. However nowadays it is irrigated by an artificial channel ramified by Ghale Chay River.

During the first decade after the Islamic Revolution of Iran, Plan and Budget Organization (PBO) embarked upon a series of studies titled "Regional Disparities Investigation" . They aimed at demarcating the country's regions based on indicators of socialeconomic- natural and infrastructure facilities. The results of these studies were instrumental in order for PBO to formulate national strategies of social equity. Attributed to it's prevailing rural economy, natural setting and diseconomies of spatial structure, Ghezel-Ozan watershed was identified as one of the most deprived regions of the country. The next step was taken by the Ministry of Construction Crusade which launched an investigation and planning project at the Ghezel-Ozan regional scale in 1993. The goal of this project was to explore underlying causes of the region's relative backwardness and to formulate policies and plans to alleviate the situation. Taking an environmental approach to regional development, this article attempts to elucidate relationships of determining resources such as water, soil, flora etc. to settlement patterns in the watershed. The main conclusions based on the findings of the project were : a) Unequal and sparsely scattered distribution of natural resources has been historically, the main determinant of appearance of thousands small villages, one forth of which is now deserted. b) Due to lack of sizable urban centers in the watershed which could assume roll of central places on the one hand, and unfavorable climate and terrain resulting in weak communication networks on the other, in addition of many deserted villages the remaining are greatly dependent upon services of outside urban centers. C) parallel to certain natural processes, economic activities such as traditional animal husbandry and agriculture are responsible for escalating resources deterioration. All in all, due to lack of planning commitments, the watershed has missed development opportunities embedded in it's both man made and natural settings.

Background and Objective: Considering the importance of fish production and consumption in the human food chain and human food security, and on the other hand, the possible adverse effects of fish pond effluents on river water quality,the present study was carried out by considering the effect of fish farm effluents on river water quality, with a case study on fish farms along the Great Ghezel Ozan river (from Chehelcheshmeh mountains of Kurdistan province to Manjil or Sefidrood dam). Material and Methods: Fish farms were identified based on field surveys along the river. Sampling from a depth of 0 –,10 cm from the water surface in summer (2017) With 5 samples about 500 meters before the pools (control) that were not affected by fish farming activities and 5 samples in approximately100 –,150 meters after the pools (where the effluents of fish farms entered the river) was done. Sampling and analysis of physicochemical parameters such as temperature, pH, electrical conductivity (EC), Nitrate (NO3), Phosphate (PO4), Dissolved oxygen (DO) and Chemical oxygen demand (COD), according to the instructions in the standard methods book was done. Findings: The results indicated that the average values of the parameters in the input and output stations, respectively for pH (7. 24 –,7. 21), EC (2250. 6 –,2282. 8 dS/m), DO (7. 41 –,6. 94 mg/L), COD (24. 94 –,29. 63 mg/L), Temp (14. 8 –,15. 5 °, C), NO3 (4. 1 –,5. 9 mg/L), PO4 (1. 1 –,1. 84 mg/L) was obtained. Discussion and Conclusion: In general, the process of acidity and oxygen parameters of the solution decreased, and the parameters of electrical conductivity, oxygen demand, chemical temperature, temperature, nitrate and phosphate, increased.

In order to prevent the long-term negative impacts of resource development projects on the riverine ecosystems, it is necessary to define hydrological and ecological needs of river in the form an ecological water-need and consider them in water allocation interactions. The main objective of the present study is to evaluate and estimate the monthly distribution of ecological flow of Ghezel Ozan river by means of hydrological methods, such as Tessman, Tennant, flow-duration curve analysis (FDC), flow-duration curve shifting (FDC-Shifting), Smakhtin and Desktop Reserve Model (DRM), and with reference to the given 25-year statistical period. The results drawn from the present study illustrated that the FDC-Shifting method is superior to other methods due to considering diverse ecological classes, focusing on natural variability of flow, and attempting to maintain this variability in its proposed ecological flows, and in order to maintain the general pattern of flow variability, it employs natural flow-duration curve shift. The abovementioned method is better adapted to the flow potential of Ghezel Ozan river as well as its ecological management method. To preserve Ghezel Ozan river in the minimum acceptable ecological status (ecological management class C), the mean annual flow intensity equivalent to 3. 11 (%23 MAR), 1. 91 (%22 MAR), 1. 43 (%25 MAR), 0. 84 (%30 MAR) and 0. 28 (%32 MAR) cubic meter per second must be determined respectively within the range of five hydrometric stations including Bianlu, Nesare Olia, Salamat Abad, Hasan Khan, and Shadi Abad.

Accurate planning for adaptation to climate change is very important in each region. In this study, using the meteorological data of the six synoptic stations in the Ghezel Ozan basin in the period 1989-2016, and by employing the four GCM models, under the two scenarios RCP4. 5 and RCP8. 5, data were generated for the horizons 2050. Then, some parameters such as the air temperature, precipitation, potential evapotranspiration (ET0), precipitation deficit (PD) during the growing season, dryness intensity were calculated. ET0 was calculated by Pristeley-Taylor (PT) and Penman-Monteith (PM) methods. Then, ET0 obtained from the PT method was calibrated using four Artificial Intelligence methods (namely Eureqa Formulize, ANN, ANFIS and SVM) with PM method for each station. For spatial analysis, three geostatistical methods namely IDW, Kriging, and Cokriging were utilized. The results indicated an increase of 0. 9-2 º C in mean air temperature and an increase in precipitation between 27 and 49 mm will be experienced in the future period. Furthermore, ET0 and dryness intensity will be increased at all the stations. The increase in average PD (in the whole basin) will be about 6% to 9%. In average, the rate of increase in agroclimatic indices in the RCP8. 5 scenario will be about four percent more than the RCP4. 5 scenario. Among the methods of interpolation, the modified Cokriging based on DEM (Digital Elevation Model) showed the more suitable one among others. The length of the growing season will be elongated from 15 to 35 days. No significant changes will be occurred for dryness period. The spatial variation of future climate variables is expected to be not changed comparing the base period.

Ghezel Ozan River Basin is one of the important basin in Iran, which supply people grains requirements. The amount of potential reference crop evapotranspiration (ET0) was evaluated with RCP4. 5 (low emission) and RCP8. 5 (high emission) scenarios on the horizons 2030, 2050, and 2070. The output of four GCM models in CMIP5 and the LARS-WG6 statistical downscaling were used. In this study, the daily historical records of six synoptic stations (namely Zanjan, Mianeh, Khalkhal, Zarrineh, Qorveh, and Bijar) from 1989-2016 were used. Differences of mean ET0 time series in the base and future time periods were tested using the t-test method in three-time scales (i. e. monthly, seasonal, and annual scales) at 5% significance level. Trends of ET0 in the proposed three-time scales were analyzed in the base and 2021-2080 periods with both RCP scenarios using the Mann-Kendall (MK) method at 5% significance level. The effect of significant autocorrelation coefficients was eliminated in MK method. The slope of trend lines was estimated by Sen’ s estimator. Results showed in the whole basin, based on the RCP4. 5 scenario in the horizons of 2030, 2050, and 2070, the amount of ET0 will be increased by 1. 8%, 3. 7%, and 5. 7%, respectively. These records were about 1. 7, 5. 4, and 9. 1 percent using the RCP8. 5 scenario, respectively. The most increase in ET0 was observed for July. The annual ET0 values would be increased in the future in all stations. The mean differences of ET0 in June, July, August, summer, and annual time series with respect to the base time period were significant for all the stations and for all the future periods (under two RCP scenarios). In the future period, according to the both scenarios at all stations, the annual ET0 trend was upward.

Dams are the most important water structures and estimating the volume of sediment input to the reservoir and its distribution is important in their operation. Ghezel- ozan River plays an important role in supply of water to the Sefidroud Dam Reservoir as well as the sediment input to it. In this study HEC-RAS mathematical model was used to simulate the hydraulic flow and the sediment in the final 14 kilometers of the Ghezel- ozan River leading to the Sefidroud Reservoir. DEM maps and the Ghezel- ozan flow and sediment data at Gilvan station and the sediment output statistics from the dam at Roudbar station in the period of 30 years were used as inputs to the model and the river sediment transport capacity was calculated. Also various return periods of river discharge were calculated with SMADA software and were used in the study. Comparing the measured and calculated data indicated that Ackers- White equation had the lowest error estimate compared to the other transport functions. In addition, Hjulstrom and Shields criteria have been utilized to investigate the erosion and sedimentation status of Ghezel- ozan River which showed the erosion status at the sampled river's sections based on the hydraulic condition of the river.

Introduction: Rivers are generally receiving wastewater from agriculture, industrial and urban areas. Population growth, urban development and human activities have always been a threat to the quantity and quality of river water flows. In general, the purer the water, the more valuable and useful it is for riverine ecology and for abstractions to meet human demands such as irrigation, drinking and industry. Conversely, the more polluted the water, the more expensive it is to treat to satisfactory levels. This leads to disruption of natural food chains and the loss of riverine lives. Protecting and improving the quality of river flows is a priority. The changing hydrological regime associated with the developing water demand schemes may alter the capacity of the environment to assimilate water soluble pollution. In particular, reductions in low flows result in increased pollutant concentrations already discharged into the water course either from point sources, such as industry, irrigation drains and urban areas, or from non-point sources, such as agrochemicals leaking into groundwater and soil erosion. Reduced flood flows may remove beneficial flushing, and reservoirs may cause further concentration of pollutants. Monitoring of water quality in different reaches of rivers depends on the purposes of water uses and requires a long-time and high-cost planning. Numerical simulation models are useful tools for a rapid and low-cost assessment and prediction of water quality in the present and in the future conditions of the rivers reaches. Different scenarios can be tested for evaluating the effects of point and non-points sources of pollutants discharging into the river, and for predicting the effectiveness of alternative restoration plans in the management of water-based lives instream and in riverine riparian areas. In the present study, the effects of discharging pollutants on water quality in a long river reach have been studied under the present condition and in different scenarios of river training schemes. Methodology: As a case study, the 51-km Diwandra-Bijar Reach of the Ghezel Ozan River was selected. Modeling of the existing conditions of river quality was performed using existing geometric-hydraulic and river water quality data. Two mathematical models QUAL2KW and WASP were used to simulate the water quality. Simulation of different parameters (such as: DO, BOD, COD, Norg, NH3, Q, h, V, T and pH) were considered. In order to calibrate these models, RMSE and MAPE statistical indices were used. Using the QUAL2KW model, five river training schemes (variation of 1-river width, 2-side slope, 3-longitudinal slope, 4-bed roughness; and 5-width and longitudinal slope of the river) were considered. Results and discussion: Comparison of river conditions simulation with two models of QUAL2KW and WASP with observational data showed that both models have the proper ability to simulate water quality. The study of river conditions showed that the river flow increased along the river due to the entry of the sub branch. Due to changes in geometry and river flow, depth and flow velocity are changing along the path. Changes in river water temperature to 35 km are decreasing and then increasing. The concentration of dissolved oxygen from the upstream to downstream of the river is decreasing. BOD concentration is rising from kilometer 19. The concentration of nitrate in kilometer 32 has increased due to the arrival of the Cham Zard River. The concentration of Norg has increased from Kilometer 19. This is due to changes in the river section and a decrease in sedimentation due to the increase of the flow and entry of pollutants into the river. Ammonia concentration also increased at Kilometer 19 with the arrival of the Cham Zard River, and finally decreased by the arrival of the Yol Gashti river. Considered scenarios showed that, with decreasing river width, flow velocity increased, resulting in an increase in the concentration of the dissolved oxygen that increased the amount of river self-purification capacity. The concentration of NO3, BOD and COD parameters also increased slightly in high Discharge. The effect of the scenario of the Side slope on the water quality and hydraulic performance of the river is very small and has the least impact on the water quality of the river. By reducing the slope of the river bed, the flow rate is reduced, so the dissolved oxygen decreases. And the concentration of BOD and COD parameters has increased and the concentration of nitrate has decreased. This scenario is appropriate for the condition where the river needs to reduce the BOD. By the roughness increases, the flow velocity decreases. Consequently, the concentration of quality parameters (such as: BOD, DO and COD) are decreased. Conclusion: The results indicated that both models are capable of simulating the qualitative status of the river reach. The results of the five river training scenarios prove that wherever the dissolved oxygen (DO) is insufficient in the flowing water, the decrease in the channel width has the greatest effect. Implementation of both the decrease in channel slope and the increase in the channel width is effective in the reduction of BOD and COD, while does not result in a significant reduction in DO. Nitrate variations are almost negligible in all scenarios, indicating a low susceptibility of this parameter to the changes the channel geometry. However, wherever the concentration of Nitrate is a major treat, the increase in the channel width together with the decrease in the channel slope would be an alternative training solution.