فهرست مطالب ali reza mirzajani

Three species Rutilus frisii, Alburnus chalcoides and Vimba persa are the most valuable fish that migrate to southern Caspian rivers especially Sefidroud river. In this study, the temporal and spatial distribution of was investigated based on presence and abundance of fingerling fish in 8 stations of the Sefidroud River, from the estuary to the Sangar Dam, during one year from March 2021 to December 2022.</span></span></span> According to the environmental conditions of stations, the sampling was done with an electrofishing instrument and a throwing net with mesh size 6 mm. The results showed that the abundance of fish fingerlings is minimal in the winter and their maximum abundance coincides with the reproduction time and after their adult spawning. The maximum abundance of these fingerlings along with their spatial distribution, also shows their migration pattern towards the Caspian Sea. The abundance of Rutilus frisii in the pebble and gravel beds of the upstream stations was the highest in April and the abundance of the Alburnus chalcoides and Vimba persa in the gravel-mud beds of the middle stations up to the estuary was the highest in August-September. The presence of Rutilus frisii fingerling, with an average weight of 2 g. was high in near to estuary in August while the other two species were present in the middle stations with high abundance until November. Rutilus frisii with weigh more than 3 grams in different stations in autumn and winter indicate the adaptability and residency of a number of fish in the river. The present study can provide some guidelines to the fish stocks restoration centers of Caspian Sea for releasing Kutum fry in the upstream areas, or fish fingerling in the middle of the river at an earlier time. This plan can be tested in a pilot program.

The Sefidroud River is the largest river in the north of Iran and has a special importance in the survival of Caspian anadromous fish. In this study, the biodiversity and abundance of fish were investigated in eight points of the Sefidroud River and one point on the sea coast from March 2022 to January 2023. There were identified a total of 40 species of fish from various ecological groups; riverine (26 species), migratory (6 species), and estuarine-marine (8 species). The highest and the lowest number of species were observed in the mid-region of the river and the marine area with 21 and 17 species, respectively. The spatial ecological niche was observed for some species such as three Gobiidae species Caspian goby (Neogobius caspius), Caucasian dwarf goby (Knipowitschia caucasica), and Iranian Goby (Ponticola iranicus) occupied the sea coast, the estuary, and the upstream area, respectively. Mugilidae species were also seen up to 10 km from the sea. The eggs and larvae of anadromous fish were observed in the highest station. Kutum (Rutilus frisii) and Danube bleak (Alburnus chalcoides) fry fish had the highest abundance among the identified species of with 222 and 92 number/200m2, respectively. Bream (Vimba persa), Leaping mullet (Chelon saliens), European bitterling (Rhodeus amarus), Sanias spined loach (Cobitis saniae), North Caucasian bleak (Alburnus hohenackeri) had moderate frequency between 27 to 59 number/200m2 and the abundant of other species was low between 0.014 to19 number/200m2. The lowest Shannon's diversity index was in the furthest distance from the Caspian with value 1.03, while the highest value, with significantly difference p<0.05, was observed in 5 km to the sea with value 1.6  Also, the highest and lowest values ​​of the index were observed in November 2022 and January 2023, respectively.

The Eurasian otter (Lutra lutra) as one of the mammals of the inland waters of Iran is at the top of the food pyramid and encounter to endanger of extinction. The diet studies are critical to understanding the ecology of wildlife and preserving their populations. The objectives of this study were the presence and diet of otter in estuary region of Acharod, Khoshkrod and Polrood rivers, in the east of Guilan province, and also the study of the level of dependency of this species on fish species of the Caspian Sea. The length of the last five kilometers of each river, as three sections with an approximate length of 1700 meters, was examined in terms of distance or proximity to the sea. The results showed that of the five km length studied of the rivers, the Eurasian Otter was present up to 4/3 km of the estuary. In total, 511 presence indices with specific seasonal changes were observed in each of the river sections. The highest index was observed in the autumn season and the lowest in the summer season. Based on the analysis and investigation of spraints, 955 prey items including fishes, crustaceans, snakes, frogs, birds and insects were observed. The highest feeding index (FI) in three studied rivers was for fish and the lowest FI was for insects. Also, the seasonal changes in food items between sections were observed. So that in the two seasons of autumn and winter in all three sections of the rivers, the highest FI was for fish. In the spring and autumn, the feeding index of the fed fish was mainly related to river fish and common river-sea fish. In summer and winter, the percentage of sea fish was higher than in spring and autumn. The feeding index of non-fish items has also increased in the summer compared to other seasons.

In this research, the identification and estimation of benthos biomass of Balikhli chai and downstream river of Yamchi dam in Ardabil province was performed to water quality determination for aquaculture. Sampling of benthos organisms in rivers conducted in 4 stations. After identification of benthos, their distribution percent, was determined the ratio of the frequency of individual of three orders of Ephemeroptera, Plecoptera, and Trichoptera to the frequency of individual in Chironomidae family and the Hilsenhoff Family Biological Index (FBI) to determine water quality condition at the stations was calculated. 11 orders and 21 families were identified from the study of river benthic species. Chironomidae family had highest number of observation and was present in 97 percent of the samplings. In terms of mean abundance and biomass, the Gammaridae family showed the highest value in station 1. Also, sensitive groups with grade 4 tolerance, namely Gammaridae, Baetidae, Heptagenidae and Hydropsychidae, were mainly present in stations 1 and 2. Biological index showed that station 1 had the lowest value of 4.4 and then, station 2 was 5.7. EPT/C index showed that stations 2 and 1 had the highest numerical values ​​of 49.5±81.7 and 10.8±16.9, respectively. In general, it was concluded from benthos investigation that according to the observation of very good to excellent biological index in station 1 and 2, which were closer to Yamchi Dam, there were more suitable conditions for aquaculture in these stations.

In order to investigate the status of Caspian Sea kutum ( Rutilus kutum) released to Khandaghlou dam reservoir in Zanjan province, a sample of fish fauna was carried out for one year. The Caspian Sea kutum was introduced to this reservoir in 2003 ( It is not clear that it was deliberate or accidental ). The results showed that the mean length of Caspian kutum caught in the Khandaghlou dam reservoir was 42.1 ± 3.1 cm with a minimum and maximum length of 38 and 46 cm, respectively. The average weight of this fish was 297 ± 1120 grams with a minimum and maximum weight of 667 and 1400 grams respectively. In the samples, the age range of this species was 3 and 5 years old, and the 4-year-old fish had comprised 67% of the catch (n= 6). In examining the contents of the stomach of caught fish there was a large amount of the shrimp of the lake (Macrobrachium niponnes) which was confirmed by Professor De Greev in samples transmitted to the London Zoology Museum. Also, the female gonads were in the fourth stage of sexual maturity. It seems that due to the high adaptability of Caspian Sea kutum, this species can be identified as one of the most suitable options for the aquaculture industry and culture-based fishery in dam reservoirs in the country.

Water hyacinth (WH) is an aquatic weed and one of the most productive plants on earth, causing serious environmental problems. Herein, some nutritional and phytochemical constituents of WH were investigated.

Chemical analysis of Eichhornia Crassipes was carried out to determine total ash, humidity, crude protein, fat, fiber, and carbohydrate contents. Total phenolic and total flavonoid contents of the hydro-methanolic and aqueous extracts of the plant were determined using the Folin Ciocalteu and aluminum chloride colorimetric methods, and HPLC was performed to quantify eight phenolic compounds. The antioxidant and antimicrobial activities of the extracts were also evaluated.

The dry matter, total ash, crude protein, crude fiber, nitrogen-free extract, and ether extract contents of WH constituted 9.4, 12.9, 24, 11.5, 49.9, and 1.7%, respectively. The total phenolic contents of the hydro-methanolic and aqueous extracts were 491.2 ± 31.9 and 258.3 ± 10.8 mg gallic acid equivalents/g of dried extract, respectively. The total flavonoid content of the hydro-methanolic extract (76.8 ± 7.8) was higher than that of the aqueous extract (46.1 ± 6). Ferulic acid was found to be the most abundant phenolic compound in both extracts. The antioxidant activities of the hydro-methanolic and aqueous extracts were determined to be 221.52 and 97.07 mg ascorbic acid equivalent/g dry weight, respectively. The aqueous and hydro-methanolic extracts showed the highest antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, respectively.

In conclusion, the present study indicated the applicability of WH as a natural source of antioxidants and antimicrobial agents.

Some reproductive characteristics of the non native oriental river prawn Macrobrachium nipponense were monthly studied in Anzali Wetland. Totally more than 2,500 prawns were caught and examined during this period, with maximum and minimum lengths of 97 and 10.05 mm and weight of 0.02 to 13 g, respectively. The average length of shrimp was 45.7±14.3 mm and the mean weight was 1.4±1.376 g. The sex ratio of females to males was 1.1±0.4 on average, which during the peak spawning months, this ratio is more inclined to females. Examining some of the reproductive factors of 244 ovigerous females within the length of 38 to 92.7 mm with an average length of 56.8±8.2 mm showed that the most frequent length and weight classes were 50 to 60 mm in length and 2 to 3 grams in weight, respectively. The minimum oviposition length was 38 mm. Total fecundity was observed 75 to 4146 oval eggs with short diameter 0.35 to 0.8 mm and long diameter 0.5 to 1.0 millimeters. The number of eggs hatched by shrimp was linearly correlated with total length and weight of shrimp. Reproductive efficiency ranged from 0.01 to 0.19. Although its fecundity is lower than other economical species of Macrobrachium, other characteristics such as reasonable reproductive output and long reproduction period can make them suitable option in aquaculture.

Oriental River Prawn Macrobrachium nipponense, originating in Japan and China, is one of the exotic species in Anzali wetland. It has a high population in many parts of it, especially in inlet rivers. To estimate the population in Anzali Wetland, 18 traps (Opera House and Hokkaido) were used during the two periods of July and August in three parts; including western area, SiahDarvishan and Sorkhankol. The trend of catch per unit of effort has been declining in July while an increase in catching was observed in August in two regions of SiahDarvishan and Saorkhankol. The average catch was 100 and 145 per unit of daily effort in August and July, respectively. The average weight of the individuals was 3.3±0.5 gr. The population was estimated 228±178 and 194±58 gr/m2 in July and August, respectively. These estimations are greater than those provided by other natural water resources such as marine areas for different species. For a clearer conclusion for potential of species to exploit are needed more investigation.

The goal of this study was to investigate in Gammarus parthicus, body length frequency distribution (male, female) and relationship between clutch size and different body parts (head, pereon, pleon). Sampling from a Qanat in 2019 was done in Birjand city (Spring, Summer, Autumn and Winter). Totally, 252 gammaruses were catched. In each sampling, one hour was attempted to catch gammaruses by a hand sieve with one mm mesh size. To measure, a stereo microscope and millimeter paper were used and the samples were photographed. With a petri dish and the plastic talc (placed over the samples) gammaruses were photographed lively. Length was measured from the beginning of the head (Rostrum) to the end of tail (Telson). In addition, head, back and tail length were measured separately. Image-J software was used to analyze the resulted images. The mean total length of males and females gammaruses in four seasons were (Mean± SE) (15.75±1.21) and (12.93±1.43) respectively. Sex ratios differed according to the seasons. The total body length was obtained as a model of the explanatory variables including head length, tail length and season. The most sex ration in spring (1.39) and the lowest one in winter (0.31) were observed respectively. The total body length was obtained as a model of the explanatory variables including head length, tail length and season. The number of eggs (clutch size) per fertilized female was obtained by tearing the bag of eggs. The number of eggs was counted in a sample of gammaruses after 10 days keeping in the climate room. The climate room was used to simulate the reproduction conditions. The number of eggs was obtained as a model of head length and tail length. The report of Gammarus in the east of Iran and the influence of season in life cycle of the Gammarus.

Aquatic plants are severely increased in eutrophic ecosystem and sometime be caused problem as different aspects. The high abundance of aquatic plants and sedimentation are the main problems in Anzali Wetland. In this study the identification and biomass of dominated aquatic plants was investigated in western part of Anzali Wetland. Among four submerged macrophytes, the Ceratophyllum demersum and Myriophyllum spicatum had the highest distribution and abundance. The biomass average were 743.8 ± 536.5 and 292 ± 311 gr dry weight m-2 in summer 2017 and winter 2018, respectively. The biomass seasonal change was more in eastern rather than western of studied area. Azolla filiculoides had a high abundant and distributed in marginal area during summer while it was completely and incredibly disappeared until winter around Anzali Wetland. Among marginal floating macrophytes, Nelumbo nucifera and Hydrocotyle vulgaris were highly distributed with 240.6 ± 70.4 and 338.8 ± 142 gr dry weight m-2 respectively. The Wetland Macropphyte Index value was nearly similar around study area and was about 1. The annually dead of macrophytes in winter can increase the eutrophication trend in Anzali Wetland. Then, it's necessary to remove the aquatic plants in Anzali Wetland to preserve of its ecological and economical values.

Lake of the Martyrs of the Persian Gulf (also known as the Chitgar Lake) is located in the north-western of Tehran. The construction of this artificial lake was done by Tehran Municipality was filled water of the Kan River in 2012. TN, TP, SD and Chl-a was used to determine trophic levels. Water sampling was performed by Rotner sampler and the water quality was investigated on 5 stations site during 2013-2019. Standard methods were used for Analysis of water parameters. To determine the difference between mean of the studied parameters, the One-way ANOVA variance analysis test and Duncan mean pair test was used, and the confidence level was 95%. Based on the study, the results indicated that during 2013-2019 the mean yearly EC was 432±65 µs/cm, pH was 7.79±0.45 and SD was 3.7±0.9 meter. The mean yearly of dissolve oxygen, total phosphorous, total nitrogen, respectively, were 8.3±1.4, 0.041±0.015, 2.828±1.342 as mg/l and chlorophyll-α was 5.2±2.7 µg/l. During the months under study, the water temperature varied between 5.8±0.4 to 28.9±0.2 as °C. The ratio of total nitrogen to total phosphorus was more than 30 which indicated phosphorus is limiting factor in the lake Eutrophication. Based on multivariate evaluation method, during 2013-2019 mean of TSI was 40.6±6.3 with range of 29-50. In the early years, TSI was oltraoligotrogh and during 2016-2017 the eutrophication state close to the mesotrophic state and then it has almost returned to its original level during the downward trend after the summer of 2018. Introducing fishes and refinery performance are two main factors that have contributed to the declining level of eutrophication in the lake.

Lake of the Persian Gulf Martyrs has been constructed in the northwest of Tehran in 22 urban areas, which in addition to creating a recreational-tourism environment, has caused an increasing economic value to the adjacent lands. The declining water quality of the lake and the increasing abundance of rough and invader fishes such as Prussian carp (Carassius gibelio) and Sharpbelly (Hemiculter leucisculus) are a threat for ecosystem of the lake. In order to control these fishes, pike (Esox Lucius) as a predator was released in the lake. After introduction of pike was studied its diet and growth, and the changes of invasive fish population in 2018-2019. Lincoln–Petersen method showed that the population of Prussian carp was decreased from 20,000 to 8,300 individuals in lake. CPUE showed that population of Sharpbelly has been reduced from 712,000 to about 3,000 individuals in the lake. Using Jolly-Seber method, population of Sharpbelly from the lake shore did not change much during the study period. The population of Pike was estimated at 575 that with continuous feeding of invader fishes had a weight gain of 3.7±6.1 grams per day. The occurrence percentage of Prussian carp was more than other preys; Sharpbelly and topmouth gudgeon (Pseudorasbora parva). Due to the increase in the size of the Pike, the small fish in the lake do not have much nutritional benefit for the pike and in the current situation, only the Prussian carp fish are fed. In order to better control of the invader fish, the use of small-sized predatory fish seems necessary.

Research on the Swan Mussel (Anodonta cygnea) population distribution and biometrics were conducted during 2015. Individuals sampling were carried out monthly from 14 stations. Length, width and height of shells was measured with using of a slide caliper to an accuracy and 0.01 mm and age of swan mussels were examined by counting annual growth on the shell surface. The highest and lowest frequency belonged to Bahambar station with 33% and Sheijan station with 8% respectively. The distribution of these shellfish is Central area and western parts of Anzali wetland. The age of shells was from 2 to 9 classes and 5 to 7 years old individuals dominated. The highest and lowest average of weight and length were calculated for Hendekhaleh station (W= 203.34 gr and L= 13.45 cm) and Bahambar station (W= 78.83 gr and L= 8.63 cm) respectively. Using Fisat ll program and based on Schiffre's method, L∞ = 13.65 cm and the growth coefficient factor 0.48 was calculated. The natural mortality coefficient was 1.154. Most recruitment (smaller in size) are observed in the months of September and early October. This indicates the existence of young reserves of reproduction and the addition of a new generation to the population. The existing reserves in Mahrooz to Bahmbar, which was the habitat of younger oysters, can be used for breeding programs of this species and preserving its stock.

Feeding Frequency can affect various commercially important features such as increased biomass, growth and decreased ratio of foods, increased body weight, increased relative size, and improved tissue composition. Experiments were carried out in 100-liter fiberglass tanks containing 25 grams of 1.2 gram Rutilus kutum with a density of 0.5 g / L. The fish were divided into four treatments including 1, 2, 3, and 4 of Feeding Frequency. Each treatment was repeated 3 times. According to the Tukey test, there was a significant statistical difference between 2 treatment with 3 and 4 treatments, and also treatment 1 Feeding Frequency (P<0.05), considering food conversion rate (FCR), special growth rate (SGR), and weight gain (WG). The results showed that the maximum and minimum amount of weight gain has occurred in treatment3 (mean= 99.09±10.93) .and 1 (mean= 47.12±10.53), respectively. The minimum of the special growth rate (0.64±0.12) was observed treatment 1 and the maximum of that (1.15±0.09) was measured in treatment3. The minimum average of FCR (2.42±0.23) was referred to as treatment3 and the maximum of that (4.76 ±1.03) was referred to as thetreatment1 Feeding Frequency. Overall results showed that feeding three a day, the most appropriate method for growth Rutilus kutum,Fingerling

The Anzali Wetland is one of the most important water bodies in Iran, due to the Caspian migratory fish spawning, located in the southern Caspian Sea basin, Iran. During a long-term monitoring program, between 1994 to 2019, identification and distribution of fish species were surveyed in five different locations inside the Anzali Wetland and eleven related rivers in its catchment area. In this study 72 fish species were recognized belonging to 19 orders, 21 families and 53 genera, including 66 species in the wetland and 53 species in the rivers. Among the 72 identified species, 34 species were resident in freshwater, 9 species were anadromous, 9 species live in estuarine and the others exist in different habitats. These species include 4 endemic species, 50 native species and 18 exotic species to Iranian waters. The number of species in different locations inside the Anzali Wetland was comparatively similar while it had high variation in different rivers. Twenty fish species are new records for the Anzali Wetland basin, including 10 estuarine, 5 ornamental, 2 riverine, one anadromous, one euryhaline and a small exotic fish.

This study carried out in order to investigate the impact of Bandar Anzali's breakwater on the diversity and abundance of Macro-invertebrates. Twelve stations were located in two sides of the breakwater in the wall and in the sea substrate. The sampling carried out from November 2017 until August 2018, seasonally. In the substrate stations on the sea side, the bivalve species Cerastoderma glaucum and Amphipod Stenogammarus compersus were observed in all stations with an average 344.1 ± 11.6 and 7.77±55.9 n.m-2, respectively. The worm species Streblospio gynobranchiata with abundance of 33.3 ± 42.5 n.m-2 was found only in the estuary section. Among the Macro- invertebrates on the breakwater wall; the Mytilaster lineatus and Mytilopsis leucophoeata were found on the sea side and in the estuary side, respectively. Their abundance had not significantly difference in different seasons. The Amphipoda Melita mirzajanii and Hediste diversicolor were also frequent in the wall of breakwater with 4106±1878 and 495±110 n.m-2, respectively. The crustacean and worms had more abundant in summer 2018 than other seasons. According to ecological indices, species diversity was more in the sea side rather than the estuary side for both habitats; the sea substrate and the wall. Furthermore, the species diversity was more in the wall of breakwater rather than sea substrate. The artificial constructs such as breakwater have an important role to increase of the species diversity.

Water Hyacinth, Eichhornia crassipes is one of the world’s worst weeds. It originates from Amazonia and be invader to other areas in the worldwide. It has recently been detected in several natural areas of northern part of Iran such as Anzali Wetland. Here, distribution of Water Hyacinth was studied in Anzali Wetland during 2015-2018. Also some biological characteristic including; evapotranspirative water losses, surveillance against salinity gradients and nutrient effect on biomass production of root and green parts were investigated. Water Hyacinth infestation was observed from 7 to 84 points of Anzali Wetland with 100 to 1000 m2 in different years. The distribution of Water Hyacinth was limited in summer of 2017 because of a prolonged temperatures below freezing winter. The seed was germinated in study area after two years. The water losses were estimated up to 2.5 times more from Water Hyacinth compared to open water. While the mortality of Water Hyacinth was observed in salinities more than 5.2 g.l-1, the leaves was increased in salinities lower than 1 g.l-1. The biomass of root was more than biomass of green part in areas with lower nutrient while it was versus in regions with high nitrogen level. Water Hyacinth has a high risk threat in the most water bodies in northern Iran because of the favorite climate situation and high eutriphication level. A multidisciplinary approach should be designed in the fight against Water Hyacinth in Anzali Wetland that awareness raising among local communities and the stakeholders is the most important.

In this study some biological aspect of Chab (Squalius turcicus) was investigated in the Taham reservoir lake in north of Zanjan. The study of length and weight structure of dominated fish species, the Chab displayed a high length and weight. A number of 251 Chab were studied that the maximum size and weight were measured about 40 cm and 870 g, respectively with average weight 223 ± 204 gr. About 40% of fishes were weighted more than 250 gr which they were ranged as commercial size. The growth model was isometric and the condition factor was varied between 0.74 to 1.85. According to reproduction indices, more than 80% of ovaries were in 3 and 4 of the maturity stages in autumn that can reproduce in next spring. These characteristic and high distribution of species in Iran and special in the Caspian Sea area can be a reason to introduce this species as a candidate for aquaculture purposes. Thus, there is need the additional studies on conservation, breeding and rearing of species for fisheries approches and the sustainable exploitation.

In the last years, an invasive species, the oriental river prawn (Macrobrachium nipponense), has adapted in Anzali wetland (Iran), and it is a treated for this wetland. Current study demonstrated the preventive strategy for capture of the M. nipponense shrimp as a valuable nutrition and fatty acids components. Samplings were done with electroshock instrument seasonally at three habitats of Anzali wetland. Results showed that there was not significant different between total fatty acids and MUFA fatty acids at three habitats (p<0.05). But there was significant different between C20:4n6, C20:5n3 and C22:4n6. The range of AI and TI indexes was between 1.4 to 2.02 and 0.42 to 0.50 respectively at three habitats. The amounts of current data, n-3/n-6 and EPA/DHA ratios were lower than the maximum amount of reported data by U.K health department. So we can suggest that this species is as a health food for human.According to the preventive strategy for control of M. nipponense population, the fishery of this species is useful as a nutritional food, economic and rural development.

The Caspian Sea, as the largest land-enclosed drainage area in the world has been endangered by various environmental pollutants, discharged from coastal catchment. In this study the trophodynamics of metals are investigated in different organisms from the Caspian food web. Furthermore, the species with potential bio-indicator abilities have also been distinguished. Nine species including three invertebrates Mnemiposis leidyi, Cerastoderma glucaum and Balanus improvises; five fish species Neogobius spp, Atherina boyeri, Alburnus chalcoides, Rutilus kutum and the Caspian seal Phoca caspica were studied in three regions of the southwestern Caspian: i.e. Astara, Anzali and Chaboksar. The stable isotope of primary producer (POM) was very various in each region compare to those from primary consumers. Phoca caspica had the highest average δ15N and TLs as the top of the food chain. The concentrations of metals for the most samples of fish were below the detection limits; while the concentrations were detected in most invertebrate samples. Our results suggested the abilities of Cerastoderma glucaum as indicator of Ni and Co contamination. Balanus improvises had a high capacity for Zn, Sr, Mn and Cu bioconcentration. By comparing ln-concentration of metals vs. TLs, no metal biomagnification was observed. The marine pollution index in Anzali region was higher than those in Astara and Chaboksar regions. While this study provides the basic data from southwestern Caspian Sea; C. glucaum and B. improvises could be proper bioindicator species for worldwide comparison of metal pollution.

The coastal areas are highly productive system that is degrading due to receiving huge amount of various pollutants. Despite of the important of north Caspian Sea estuaries the quality index of benthic fauna received less attention. In this survey the benthic population of 18 rivers estuaries in southern Caspian Sea were investigated. The benthic sampling and identification were conducted at eight points in each estuary in three periods of winter، spring and summer 2009. The Shannon Wiener diversity and the Hilsenhoff biotic indices were used for evaluation of environmental quality. The result of Shannon Wiener index values in various rivers indicates that Astara and Lemir had the lowest and highest diversity respectively. The station 1 and 2 in river showed the lowest and offshore stations 5، 6 and 7 the highest diversity values. According to Hilsenhoff biotic index for water quality classification، the stations of 1 and 2 with low quality were significantly difference with other stations. The quality of estuaries of Khotbesara، Navroud، Heshmatrud and Shirabad were strongly good and the other were slightly and moderately good condition. In generally، the quality of rivers in western region were better than the other regions، where they were characterized on the base of seasonal condition، biological properties of benthic fauna، morphology and watershed basin of the river.