The hydrochemical study of Chitgar Lake

The man-made Lake of the Martyrs of the Persian Gulf (also known as the Chitgar Lake) is located in the northwestern of Tehran and was established in 2012 and field with Kan River water at the same year. The water quality was investigated on 5 sampling site during 2013-2014. Standard methods (APHA, 2005) were used for Analysis of water parameters. The results indicated that the mean monthly temperature of water was 18.4±7.3 °C. The mean monthly EC level was 373±30 µs/cm. The mean monthly total hardness, dissolved oxygen, total phosphorous, total nitrogen, silicate, respectively were 119±5, 7.8±1.2, 0.04±0.01, 2.06±0.41, 9.6±0.5, all as mg/l,. The mean chlorophyll-a was 1.6 ± 0.81 µg/l. All parameters showed no significant differences between stations (P>0.05), while total hardness, chlorophyll-a, Do, total phosphorus and silicate showed monthly significant differences with 95% confidence level. The ratio of total nitrogen to total phosphorus was 51 which indicated phosphorus is limiting factor in eutrophication process. According to Carlson trophic index determined to be oltraoligotroph (TSI<40). The result indicated that changes in nutrient concentration is under biological activity influence

Study of Shovier and Mirzakhanlo dam reservoirs in Zanjan province in order to aquaculture activity

Inland water aquaculture activity have been known as an important approach for protein production while reservoir lakes recognized to have a significant potential for this purpose. Zanjan province in Iran with several dam reservoirs is suitable for aquaculture development. This study was conducted on biotic and abiotic factors of two lakes Shovir and Mirzakhanlo in order to determine aquaculture potentially of reservoirs. This two lakes located on different climatic region; Shovir located in region of semi arid area with very cold weather in winter, while Mirzakhanlo is in semi humid area and warm weather characteristic. In this study the plankton, benthos and fishes were assessed and the 15 hydrochemical factors were measured in order to determine the fisheries potential for fish introduction or release. The results showed that the phytoplankton abundance of Mirzakhanlo varied between 1.6 to 45.2 million cell/l. with 32 identified genus. The zooplankton abundance varied between 48 to 632 n/l. and 22 identified genus. The abundance plankton in shovir varied between 1.350 to 34.2 million cell/l. and 240 to 4500 n/l. for phyto and zooplankton respectively. Macrobenthos biomass were 21.4 and 0.34 g/m^2 in Shovir and Mirzakhanlo lakes respectively while Chironomidae and Tubificidae families were dominant groups. The lake sediment organic matter were 4.3 and 3.2 % respectively. In ichtiology survey identified 5 and 7 species in Mirzakhanlo and Shovir lakes respectively. The hydro-chemical results indicated no restriction for aquaculture activity and according to trophic model both lakes are recognized as meso-eutrophic and eutrophic. Despite of climatic restrictions, the potential for fish production was estimated about 321 and 151 kg/ha for Shovir and Mirzakhanlo lakes respectively that can be improved by using agricultural and the other native facilities

Study of Todebin dam reservoir in Zanjan province in order to aquaculture possibility

The Todebin dam reservoir has been constructed in central part of Abhar in the Zanjan province which has been studied with aquaculture purpose. This study was conducted on biotic and abiotic factors. The plankton, benthos and fishes were identified and the parasitology and bacteriology studies were performed on the lake fishes. Then the fisheries potential of the lake was calculated in respect of final fish farming amount and the fish releasing. The results showed the Bacillariophyta was dominated ِduring the study. the highest abundance of phytoplankton was between 2.1 and 12.5 million cells.l^-1 in the upper layer of lake as compared with the lower layer. The genus Cyclotella and Dinobryon belong to phytoplankton and Keratella and Polyathera belong to zooplankton were dominanted abundance. The mean biomass of benthos was varied from 5.5 to 29.5 g.m -2 and the Chironomidae had the most abundance. The ichtiology survey showed the presence of four cultured species and the Goldfish. The hydro-chemical results indicated no restriction for aquaculture activity. The oxygen average was more than 8 mg/l. The average of phosphate, nitrogen and hardness were measured 0.09±0.04, 2±0.8 and 237±94.5 mg/l., respectively. For the most hydrochemical factores, the values were significantly different between upper and bottom layers of the lake. The oxygen production and Chl-a amount were measured about 0.73 mg/l. and 7/03 µg/l., respectively. According to climatic restrictions, the cold fish culture is preferred than to culture of warm fishes. While the natural capacity of the lake was about 5 tones to warm fish culture, the fish production of trout was estimated about 40 tones. This volume will be available during four months periods and twice a year

Biological survey of Caspian kutum (Rutilus kutum) released fingerlings in Sefidroud River (Guilan Province)

Kutum fish (Rutilus kutum) is an anadromous cyprinid species that spawns in adjusted rivers to the Caspian Sea. Many million fingerlings were artificially produced and annually released in these rivers specifically in Sefidrud River by Iranian Fisheries Organization. In this study were estimated the staying period of Kutum fingerlings in Sefidrud River and its diet and growth. A small piece of the caudal fin was cut as a tagging method. About 50000 and 5200 individuals were marked during July and September 2013, respectively. The marked fish had an average total length 53.2±5.6 mm and body weight 1.11±0.26 g and were released in river around two kilometers of the estuary. The sampling of fishes had been earlier started from Feb. 2012 and continued until Feb. 2013 at five stations. Four stations were along river from three Kilometer of estuary to estuary and one station was in right side of estuary in the sea coast. The results showed that marked samples after releasing time were distributed in all studied area from 3 kilometers of estuary to estuary but they migrate mainly toward Caspian Sea in a short time. However the marked samples were observed in estuary and the sea coast after 6 and 24 hours of their releasing time, respectively, Kutum fingerlings remained in Sefidrud river ecosystem in a longer time, at least until end of our sampling period i.e. 105 days. The coefficient of vacuity index of the natural feeding study was 0.0, 49.0 and 30.6 % for phytoplankton, zooplankton and benthos, respectively. The average of GastroSomatic index, intensity of fullness and condition factor were calculated 6.30±3.25, 174.6±153.2 and 0.92±0.09, respectively. A temporal and spatial variation on main food items were observed in gut content of fish fingerlings from different locations and seasons. Gut contents were generally included 59 genera of phytoplankton, 15 groups of zooplankton and 10 groups of benthos. Nitzschia, Navicula and Synedra were dominated among phytoplankton genera with 45.83, 18.02 and 15.99 %, respectively. Among zooplankton groups; the Rotaria, Moeina and Difflugia were dominated with 22.30, 20.86 and 15.83%, respectively. Chironomidae and Gammaridae were the main food items among fed benthic animals with 83.67 and 11.15%, respectively. Furthermore 48 phytoplankton genera, 32 zooplankton genera and 6 benthic families were identified in ecosystem of Sefidrud river. Bacillariophyta phylum (with 23 genus), Rotatoria (with17 genus) and Chironomidae family were dominated in each mentioned groups, respectively. It is concluded that the Kutum fingerlings stay in Sefidrud River for a long time, although most of them migrate to Caspian Sea during first month after releasing. However dietary indices were normal in studied samples, the condition factor index seems to be low