Objectives: Ahawzas one of the metropolises of Iran in classified among lowland plains with low slope in terms of topography. In this city, unsystematic construction and immediate rainfalls and showers are the mainsources of flooded street.Method: The present study has a descriptive-analytical approach and is based on causality method. using geographic information system software (GIS) and RIVER tools techniques, this study seeks to identify and manage of surface waters and urban floods in District 1 of Ahwaz during rainfalls and then the maps of slope, their direction and areas with flooding potentials are prepared.Findings/ Results: given the low slope of the area, the gravity drainage and pumping of water to Karoon RIVER is impossible due tohighcosts. However, using GIS analysis, the natural routes are determined for water drainage and finally, the map of proposed surface water disposal system in the study area is presented.Conclusion and Suggestion: In District 1 of Ahwaz, the tree orhierarchical surface water collection network has been predicted based on urban streets and alleys. The collected wateris directed to the channels and then transferred to Karoon RIVER.

Iran has common borders in 1336 Kilometers direct line with its western neighbor Iraq from Dalamparagh to Bandar Fav. The borders of Iran whether in water or in land are such that weaken the position of Iraq. Kermanshah province is a mountainous region between Iran plateau and Mesopotamia plain and is completely covered with peaks and heights of Zagros, and the heights of border areas of Kermanshah province dominate the Mesopotamia plain and provide a very favorable condition for attack operations. Observing the political map of Iran in Kermanshah province we could see that the borders of Ghasre Shirin and Naft are among convex borders of Iran and could be very tempting for Iran regarding military and political aspects. For this reason Iraq started its military attack to border cities of Ghasre Shirin and Naft when it commenced war with Iran. In this article we will review the border regions of Kermanshah province and its role in the military and political targets.

The Lateshur Watershed is a part of Central Iranian drainage basin located northeast of the city of Pakdasht in northeastern Tehran Province. This watershed has an elongate form and its surface area is more than 22.2 square kilometer. It is a part of central Alborz zone and geologically is composed of Neogen red beds units, Hezardareh Formation and Quaternary alluviums.Geomorphologic studies show that this watershed is within an anticline and surrounded by Dahaneh Mountains in the south and Gara-aghaj Mountains in the north respectively. Structural and lithological variability have a very important role in the formation of this watershed; therefore, the watershed has the same trend as structures (NW-SE). Based on this study, the Lateshur RIVER has a braided pattern with gravelly bed. Sedimentological studies along RIVERs in Lateshur basin show that three basic factor (sudden changes in slope gradient, floods events and distributaries) are the main reasons for changes in texture of bed load sediments within the channel as well as the break in sedimentary links. Lithofacies identified in this watershed include gravelly (Gmm, Gmg, Gcm, Gt), sandy (Sp, Sm, St, Sh) and muddy (Fl, Fr). Based on lithofacies, Boundary surface and current direction architecture elements identified in main RIVER of Lateshur basins include: (1) Gravel bars and Bed forms [Element GB], (2) Lateral Accretion deposits [Element LA], (3) Sandy bed forms [Element SB] and (4) Fine grain classtic deposits [Element FF]. Also, based an lithofacies and architectural elements, Facies models have been purposed for the Lateshur RIVER from upstream toward downstream as fallows: Shallow gravel braided RIVER, Gravel wandering RIVER, Gravel bed meandering RIVER, Sandy meandering rive and Fining grain meandering RIVER.

1-Introduction: Climate change is one of the big challenges of human and is accounted as a serious threat for the earth planet. Increasing global temperature will cause deep and wide changes in the climate and especially in the time and space of precipitation and storms. Many studies have approved the occurrence of these changes, and the amount and intensity of them. In most of studies, statistical models (based on historical data) or Atmosphere-Ocean General Circulation Models (AOGCM) determine the increase of carbon dioxide emissions and subsequent changes in air temperature and precipitation. Then the changes in RIVER flow rate cased by climate change are calculated by using rainfall-runoff models. But many of these studies only use a limited number of models and emission scenarios that may not include all the facts. Therefore in this study the results of 20 AOGCM models have been considered to explain the climate projection of time horizons 2040, 2070 and 2100. Also a big range of emission scenarios have been studied and using the selected scenarios and models, the amount of Sheshpir RIVER flow (one of Zohre-Jarrahi RIVER basin branches in the south west of Iran) has been detected.

According to this reality that in Iran, especially in Khuzestan, there are many RIVERs, and also due to extensive dam construction in this area, it is important to determine the rate of sediment transport. Simulation of sediment transport in Dez RIVER (between Harmaleh & Bamdezh reach) has been carried out by HEC-RAS 4.0 and GSTARS 2.1 models. In this paper, models were run by theoretical sediment transport relations to compare the results of laboratory data, and determine the best relation for calculating the RIVER sediment. It compares the two model outputs and depicts the difference between one-dimensional and quasi two-dimensional models and also the results of sensitivity analysis on these models. At last, the rate of sediment transport was estimated.

Introduction: Dischange of domestic, agricultural and industrial waste water into the RIVERs increase chemical substances such as nitrate and phosphate. These chemical changes increase algal population. High density of algae may cause changes in color, odor and taste of water. Some of the algae such as Oscillatoria, Microcystis and Anabeana produce toxins and in high concentrations may kill fishes. While Zayandehrud RIVER is considered as one of the main water supply sources for drinking water and valuable water resources of Isfahan Province, water quality control of this RIVER is important. The study of algae of the RIVER in relation with the concentration of nitrate and phosphate is the purpose of this research project. Methods: To perform this projects, seven sampling stations from "Pole Vahid" to .Pole choom. were selected. Grab methods were used for sampling of the RIVER water. 147 water samples were collected in one year of the study.The samples were analyzed for phosphate, nitrate and genera of the algae. Nitrate and phosphate of the water samples were determined using Phenol Disulfonic Acid and Stanous chloride methods, respectively. The genera of the algae were detennined using the keys. Results and Disccusion:The result of the study showed that the frequency of the algae increased with increasing nitrate and phosphate. Overall.35 genera of algae in the area of the study were observed, which six of them were indicators of water pollution. Minimum frequency of indicators of pollution was observed in the enterance of Isfahan city and maximum frequency was observed after the discharge of municipal water from waste water treatment plant (pole Choom).

Background and Objectives: The occurrence of climate change and its impact on surface water and groundwater resources, along with inappropriate management of water resources have led to an increase in the social and environmental vulnerability of RIVER systems. Assessing the vulnerability of RIVER basins, especially in developing countries such as Iran is essential and is considered as one of the main priorities of the water resources planners for the sustainable management of these resources and for the formulating of policies consistent with the regional conditions. In this line, this paper focuses on the assessment of the vulnerability of the Jarahi RIVER Basin. Materials and Methods: The study area of this research, the Jarahi RIVER Basin, is located in southwest of Iran with an area of about 24000 square kilometers and a population of about 870000 people. In this research, the RIVER Basin Vulnerability (RBV) method was used to assess the vulnerability of the Jarahi RIVER Basin. This method examines the vulnerability of ecosystem and human simultaneously and consists of a total of six main indicators including ‘ governance’ , ‘ economic status’ , ‘ social condition’ , ‘ environment’ , ‘ water stress’ and ‘ natural hazards’ indicators. In this method, data are evaluated quantitatively. The combination of these indicators is based on a raster summation algorithm which can be carried out in the ArcGIS platform. Results: The anlysis shows that the vulnerability of the Jarahi RIVER Basin corresponding to each of the indicators of governance, enconomic status, social condition, environment, water stress and natural hazards are 0. 76, 0. 41, 0. 061, 0. 43, 0. 44 and 0. 84, respectively. The results exhibit that the Jarahi RIVER Basin is severely threatened by natural hazards and in particular, the flood hazard threatens all parts of the RIVER basin. It is also exposed to high water stress. The highest water stress (0. 76) associated with the Shadegan sub-basin that is located in the southern part of the basin. In addition, the Saiddon sub basin has the lowest literacy rate among the sub basin of the Jarahi RIVER Basin with the rate of 79%. A significant part of the Shadeghan sub-basin exhibits considerable environmental impacts, interpreted as a discernible sign of human footprints in the area. Conclusion: Generally, in the Jarahi RIVER Basin, the vulnerability of three indicators, namely governance, water stress and natural hazards are quite significant. In particular, flood assessment analysis shows that almost all the RIVER basin is highly susceptible to flood hazard. Also, seismic hazard threatens a considerable portion of the Behbahan and Takht-E Deraz sub-basins. Moreover, regarding the natural hazards, given the high potential of drought, flood and earthquake occurrences in the research area, it is possible to somewhat reduce the incurred damages caused by these phenomena in the RIVER basin by means of paying due attention to knowledge, awareness, planning and efficient management. The results regarding the water stress show that almost half of the basin (mostly the Shadegan sub-basin) suffers from high water stress. Concerning the water stress indicator, given that the excessive use of water in the agriculture sector is mostly responsible for the high vulnerability state, changing the current land-use and accordingly the cropping pattern in the Jarahi RIVER Basin will potentially have a positive impact on water stress indicator. Through controlling corruption, improving Iran’ s political stability status and reducing the government fragility index, an improvement in the governence indicator can be achieved.

Introduction: An important characteristic of RIVER is channel form and meandering RIVERs for active forms. Dams as barriers to water and sediment flow can create discontinuities in fluvial geomorphological conditions. The objectives of this paper are to assess the effects of reservoir on the meandering RIVER morphology. The Gorgan RIVER catchment is located in the southern part of Golestan province with a total area of 11، 380 km2. This RIVER is originated from the Alborz Mountains into Caspian Sea. A reach of the RIVER، 44 km long، that is examined in this research is situated in middle Gorgan RIVER، between Gonbad Kaboos city and Digjeh. The construction of reservoir and changes in land use is effective on the main activities that potentially impact water regime، sediment transport and fluvial dynamics in the Gorgan RIVER. Materials and method: The data of the flow discharge and suspended sediment load of Gorgan RIVER are available in 1973-2015 at the Ghazaghli gauge station (73 km downstream from the Golestan reservoir Dam). The hydrological analysis was divided into two periods: before dam construction (1973-2001) and after dam construction (2001-2015). Sediment rating curves were created by daily mean suspended sediment discharge and daily mean water discharges by a power function. The fluvial changes have been measured using aerial photographs of 1967 at a scale of 1: 20، 000، Landsat satellite images (Landsat TM) 2001 and Google Earth images، 2015. The RIVER was digitized from photographs and satellite images، after they were geographically referenced with the help of ArcGIS 10. 2. Meander morphology was described based on some of form parameters such as wavelength، amplitude and radius of curvature، and bank width of the channel. Lateral migration and channel activity was analyzed as geomorphic activity. The normality hypothesis was studied for each parameter and conducted with the Kolmogorov– Smirnov test. If the normality test was not rejected، an ANOVA test was applied. If the normality hypothesis was rejected، the Kruskal– Wallis test was used. In all cases، the significance level assumed was α =0. 05، as a threshold for rejecting the null hypothesis. The spatial distribution for these parameters was analyzed in order to change downstream the channel. Thus، the correlation coefficient of Spearman was calculated. Results and discussion: During the pre-dam period (1967– 2001)، mean discharge below the dam was 14 m3 s-1. These values were 10. 5 m3 s-1 after the dam was constructed (2001-2015). Power regression between suspended sediment discharge and water discharge data shows that suspended sediment load is reduced to 50 % after dam construction. The values of wavelength and amplitude show minor differences in the three records and do not show significant differences. The radius of curvature، the length in 1967 (124. 7 m) was reduced in 2001 (100. 6 m) and 2015 (103 m). The dispersion values show significant differences، with a maximum in 1967 and reductions in 2001 and 2015. Bank width shows significant variations in the three records. In 1967 and 2001، it reached the values of 31 and 33 m، respectively. This is decreased to 15. 7 m in 2015(-50% from 1967). Thus، bank width loses half of its value in the pre-dam. In pre-dam period (1977-2001) channel lateral migration was reached 39. 3 m and in post-dam (2001-2015) the displacement was recorded to 22. 2m. The channel activity during the time period 1967– 2015 reached 0. 65 m/y. The ratio between radius of curvature and the bank width (Rc/W) is changed from 4. 14 in 1967 to 3. 04 in 2001 and 7. 48 in 2015. These results have indicated that migration capacity is decreased. The stability state shows the spatial distribution of the values. There is no significant relationship between landuse and lateral migration. Conclusion: After construction of the three dams، upstream flow discharge is reduced (26%) and mean width of RIVER is reduced (50%) from 2001 to 2015. Suspended sediment discharge has decreased (50%) after the construction of dams. Wavelength and amplitude do not show significant differences throughout the time period. The ratio Rc / Wb doubles from 1967 to 2015. The results show that geomorphological activity is decreased and a static equilibrium was obtained

Background and Aim: The aim is first to express the differences and identify three models, namely, Gene Expression Programming (GEP), Neural-Fuzzy Network (ANFIS), and Bayesian Network (BN), and compare them with each other. Furthermore, the research's central question is whether the superior simulation meta-modal in this study can be a suitable alternative to conceptual models in the conditions of lack of data and information. Methods: The data used for this study are the daily rainfall and flow data of the Gamasiab Nahavand RIVER in 10 years from 2002 to 2012. For the prediction or simulation stage, the data of the blue year 2012-2011 have been used. Results: In the training phase and according to the coefficient of explanation and the square root of the mean squares error and the AIC criterion, it is observed that in all three models, both in the training phase and in the test phase, we see a minimal difference in the amount of these parameters. Moreover, all three models' results are close to each other with almost a minimal difference, and almost the relative superiority of the GEP model can be seen. Discussion & Conclusion: The results indicate that the simulator meta-model of gene expression has an excellent ability to simulate and predict the RIVER's daily flow, this simulation meta-model can be a suitable alternative to models in the absence of data and information. Be conceptual. Also, the speed of implementation of the gene expression programming model was faster than other models and was able to provide results in a short time.

The length-weight relationships for three fish species from Beheshtabad RIVER, Karun RIVER Drainage (Western Chaharmahal and Bakhtiari Provinces, Iran) were investigated. The values of the slope parameter (b) in the length-weight relationship equations were determined as 2. 79 for Capoeta damascina, 3. 10 for Chondrostoma regium and 3. 09 for Oncorhynchus mykiss, all of which were significantly different from the expected b=3 value, indicating a negative allometric growth pattern for Capoeta damascina and positive allometric growth patterns for Chondrostoma regium and Oncorhynchus mykiss.