ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2021-05-19
    Description: 360 funnel traps were prepared as 30 in one row. They were bitted and located in different depths in sampling sites. Two rows each composed of 30 traps were located by stone, linking rope and boat with 50 m distance in sampling stations. The results showed that the average of total length of caught crayfish was 106.26±12.89 mm and their mean weight was 38.79 ± 15.54 gr. The largest crayfish had 171 mm length and 216 g weight. Also mean of total CPUE was 9.72±4.49 individuals in the study period. The evaluation by Schnabel approach indicated that fluctuation range of freshwater crayfish biomass with more than 120mm length was 131-313 with an average of 212.59 ±30.23 kilograms per ha. In this study freshwater crayfish biomass with more than 120mm length was 247 × 10^3 kilograms. The Maximum Sustainable Yield (MSY) was estimated 83 × 10^3 kilograms. In this study ّFecundity and biometry of crayfish (Astacus leptodactylus) was investigated during 2012-2013. The results showed that the average of total length of caught crayfish was 106.26±12.89 mm and their mean weight was 38.79 ± 15.54 gr. The largest crayfish had 171 mm length and 216 g weight. Mean number of ovarian and pleopodal eggs were estimated at 286 ± 82 and 246.31 ± 80.41 eggs (with 95% confidence limits), respectively. In this research, male to female ratio was obtained 1.21:1. The time of male moulting at 16° C was started from April and was ended in the late May, when the water temperature reached to 18° C. The second moulting of males and the first moulting of females was performed simultaneously in 18° C water temperature at September. Reproduction of freshwater crayfish was started from November and continued to May of the next year. Harvesting period was from May to late November.
    Description: Iranian Fisheries Science Research Institute
    Description: Published
    Keywords: Freshwater ; Crayfish ; Astacus leptodactylus ; Fecundity ; Biometry ; Population changes
    Repository Name: AquaDocs
    Type: Report , Refereed
    Format: 104pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2021-05-19
    Description: This project was carried out in order to determine the hatching conditions and laboratory culture methods of Fairy Shrimps ( Phallocryptus spinosa). Physico- chemical factors and phytoplankton of natural habitat of this organism was investigated in Khasellou region around Azarshahr – East Azarbaijan province. The results showed that occurance and growth of fairy shrimps in their habitates were beginning from early Aprill and their survival was decreased with increasing temperature, precipitation and increasing the salinity of their culture medium. Then they disappeared. Their habitat phytoplankton contained 3 phylla and 10 genera, from which green algae enjoyed the greatest density in May. The pool salinity was around 20-17 g/l , when metanauplii was observed in early spring. In the pool containing and without fairy shrimps the oxygen concenteration was high (9 mg/l) and low (2.9 mg/l ) , respectively . In 9 prawn ornamental fish genera, feeding with fairy shrimp showed a significant higher fecundity and hatching percentage compaired to manual diets (cow liver, spinach). In all groups fed with fairy shrimp the duration of spawning time were reduced from 15 to 8-10 days and the color was enhanced. The means of cyst number per captured female also, cyst , decapsulated cyst and Naupilli diameters were mesured 142.9±19.0 cysts , 273.2 ± 4.9 µ , 242.4± 3.8 µ and 542.6 ± 27.0 µ., respectively . The hatching rate was increased by reducing temperature and salinity of their culture mediums from 25 to 15 ◦ C , and 28 to 18 g/l, respectively.The highest hatching was observed on 5 th day at 15 ◦ C and 18 g/l (5, 33 %). In addition, low but multiple hatching was observed. Therefore , water temperature and salinity affected hatching rate in this species.The hatching success of Phallocryptus spinosa cysts was beter when collecting cysts together with dry sediments of their habitat without separation sensetive cysts . In addition to cold keeping and freezing, the hydration – dehydration method caused more diapause deactivation for hatching induction. The laboratory results revealed that the survival of fairy shrimps were highest at 15 ◦ C (42%) and lowest at 25◦ C (26%), respectively. Also, their life was inhibited in 30◦ C.In different salinities, the mean survival rate were 26% (Salinity = 15 g/l) and 20% (Salinity = 25 g/l), respectively. The mean survival percentage of Phallocryptus spinosa cultured in natural habitat water (64.3%) was higher than aerated tap water (23, 3 %). Also, feeding with Nanochlorepsis caused higher survival rates. On the other hand, Beakers yeast caused higher mortality rates. Therefore , regarding to relatively high sensitivity of these species to physico – chemical and nutritional conditions of their culture medium, it is better to culture these species with expantion of their natural habitat in order to preserve their biodiversity , culture and increase stocking density with regard to environmental considerations .
    Description: Iranian Fisheries Science Research Institute
    Description: Published
    Keywords: Physico-chemical ; Environmental ; Fairy Shrimps ; Phallocryptus spinosa ; Hatching ; Culture ; Biotechnique ; Species ; Anostraca ; Phytoplankton ; Growth ; Temperature ; Salinity ; Phylla ; Feeding ; Survival rate ; Mortality ; Biodiversity
    Repository Name: AquaDocs
    Type: Report , Refereed
    Format: 104pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2021-05-19
    Description: The Aras reservoir, located in the north-west of Iran, plays an important role in fisheries, drinking and agricultural water supplies and recreational activities in the region. This study was performed to characterize the seasonal fluctuations of phytoplankton communities and their relationship with environmental factors in the Aras reservoir from August 2013 to May 2014. Sampling was carried out seasonally from 5 sampling locations. In each location three samples were taken for phytoplankton identification and enumeration, chemical analysis and chlorophyll a determination. In total, 72 species belonging to 5 divisions were determined. Cyanobacteria contained the highest density (74%) during the study period with Pseudanabaena limnetica as the most abundant species. This group retained its dominance the whole year round which indicated the poor quality and high nutrient load of the Aras reservoir, mainly due to human activities. On average, Trophic State Index (TSI) showed that water in the reservoir was eu-hypereutrophic. The results indicated that phytoplankton density negatively correlated with Secchi disc depth (R2 = -0.479), total alkalinity (R2 = -0.564), total hardness (R2 = -0.727) and HCO3 concentration (R2 = -0.589). On the other hand, there was a positive correlation between the phytoplankton density and TP (R2 = 0.734). A comparison between the present and a previous study indicated that the cyanobacterial bloom pattern in the Aras reservoir has shifted from warm season toward an all year round cycle which in addition to basin pollution due to anthropogenic activities, can be related to global warming and climate change.
    Description: Published
    Keywords: Ecology ; Pseudanabaena limnetica ; Phytoplankton ; Water quality ; Reservoir ; Cyanobacteria ; Trophy 1-Faculty
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.1318-1336
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2021-05-19
    Description: This study was performed to compare the efficiency of six microalgae namely Dunaliella tertiolecta, Tetraselmis suecica, Nannochloropsis oculata, Chaetoceros sp., Chlorella sp. and Spirolina sp. on the growth, survival rate and reproduction efficacy in Artemia urmiana in laboratory conditions. Artemia cysts were harvested from Urmia Lake and hatched according to the standard method. Live microalgae were cultured using the f/2 culture medium. Artemia survival was determined in treatments on days 8, 11, 14, 17 and 20. A highly significant difference (p〈0.01) were found among three microalgae in terms of length growth, survival rates and reproduction characteristics in A. urmiana. In spite of higher length growth of A.urmiana fed on N. oculata than A. urmiana fed by T. suecica but survival and reproduction in the latter was better than the first treatment. In general, D. tertiolecta was more efficient than other microalgae examined in the present study on A. urmiana concerning not only to growth and survival but also to reproduction mode. So, it is preferred to feed A. urmiana.
    Description: Published
    Keywords: Ecology ; Dunaliella tertiolecta ; Tetraselmis suecica ; Nannochloropsis oculata ; Chaetoceros sp. ; Chlorella sp. ; Spirolina sp. ; Artemia urmiana ; Microalgae ; Length growth ; Survival rate ; Feeding
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.727-737
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2021-05-19
    Description: The abundance and species composition of ciliates were analyzed in the Bukan Dam Reservoir (West Azerbaijan, Iran) from January to December 2008. Surface water samples were collected at monthly intervals from the middle (Stations 1 and 3) and shallow (Stations 2 and 4) areas of the lake. Three samples were taken in the water column using a 5-litre sampler. Totally 30 liters water was collected, 200 ml of which was fixed immediately with 8.6 ml of a saturated HgCl2 solution and stained with 0.04% bromophenol blue. Three subsamples were counted in a 5-ml chamber and examined with a microscope (100 x) as well as Chlorophyll a and a few ecological parameters such as dissolved oxygen, pH, transperancy and water temperature were measured. Totally 50 ciliates species were found in Bukan Dam Reservoir. Regarding the density, a high-density period was detected from January to April with a mean density of 2.86 x 103 cells.l-1 Ciliata at stations 1 and 3 and 4.16 x 103 cells.l-1 at stations 2 and 4. The high density of ciliate in summer may be due to the increase in the density of bacteria and moderate metazooplankton as a result of the appearance of non-edible algae . The ciliata occurring at the highest densities were Coleps tessellates, Didinium nasutum, Paradileptus elephantinus, Stentor polymorphus, Zosterograptus labiatus, Paramecium bursaria, Cyclidium citrullus, Vorticella campanula, Halteria grandinella and Aspidisca costata. The maximum and minimum chlorophyll a values observed at the reservoir water were 10.39 µg.l-l and 1.0 µg.l-l being obtained in May and Octobor respectively.
    Description: Published
    Keywords: Ciliata ; Density ; Bukan dam reservoir
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.444-453
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2021-05-19
    Description: In order to study plankton population composition and species diversity in different regions of Aras rivers and the evident reservoir sampling was performed monthly from determined sampling sites from April 2007 to March 2008. Sampling was conducted in reservoir lake by a PVC pipe with 2.25 m length and 5 cm diameter by columnar method. Besides, in more dipper (〉5 m) sites, sampling conducted from bottom to surface with 1-m intervals (layer sampling) by a 2-liter Ruttner type sampler. In river due to water flow sampling was conducted by a scaled measure. Phytoplankton sampling was performed by 1-liter bottles. Zooplankton was sampled by filtering of 30 L through 55- micron plankton net. These samples were then transferred into bottles and sampling date and the name of station were attached on the bottles. Then, the samples were fixed immediately and transported to laboratory. It should be mentioned some physical parameters were determined in situ. Also, a 1liter and another 2-liter water were collected to determine chlorophyll a and chemical factors respectively. Samples were preserved in dark and cold place for a week. The upper layers (without phytoplankton) were removed and the lower layer (with phytoplankton) was sampled into 5-ml chambers. The enumeration and identification was performed by a Nikon TS100 inverted microscope with ×400 (Phytoplankton) and ×200 (Zooplankton) magnification according to Utermohl (1958) method. About 50 fields were enumerated for each sample. The comparison of physicochemical and biological factors with standard criterion indicated that the presence of a fertile plain, agricultural growth, drought and higher water demand in recent years, as well as, higher population density, the Nakhjavan city location and sewage water flows into the Aras reservoir, the lake is going to be an eutroph lake. Sampling of crayfish was performed from 5 sampling sites seasonally. Aras reservoir freshwater crayfish biomass was sampled in 1391, by putting 100 funnel-shaped nets. At each site one row nets composed of 20 nets were put by rocks, connecting robe and boat. Twenty four hours later, total freshwater cray fish was sampled (at least 300 crayfish was randomly sampled from each site). The samples were transported to laboratory and their sex, sex percentage, biometric characteristics including length, weight were recorded. Length and weight groups were estimated totally and for males and females in each season. The average total length and weight were 106.43 ± 7.94 mm and 35.81 ± 10.86 gr respectively which both are lower than West-Azarbaijan fisheries criterion. In this study only 18.99 percent contained a length higher than exporting level (120 mm). Yet, only 16.46 percent of harvesting had higher than 50 g (exporting level). With regard to data, freshwater shrimp (Astacus leptodactylus) in Aras dam reservoir stock has reduced. In general, male-female ratio was high. The comparison of growth equations confirms that males had higher weights than equal females. In recent years, the freshwater crayfish harvesting has been declined due to increased harvesting and over loading of nutrients into the lake.
    Description: Iranian Fisheries Science Research Institute
    Description: Published
    Keywords: Astacus leptodactylus ; Environmental conditions ; Plankton ; Population ; Species ; Diversity ; Sampling
    Repository Name: AquaDocs
    Type: Report , Refereed
    Format: 111pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2021-05-19
    Description: Urmia Lake is one of the two large hypersaline lakes in the world which have Artemia. It is located in northwest of Iran. Due to a decrease in water inflow and volume, the salinity of Urmia Lake has reached to more than 300 g.l-1 since 2001. The increased salinity has greatly influenced biological aspects of the lake, and caused the lake undergoes at critical conduction. The aim of the present study was to investigate the distribution fluctuations of phytoplanktons and selected physicochemical factors in relation to Artemia distribution in Urmia Lake during 8 months. Statistical analysis of mean values of ion concentrations and phytoplankton abundance indicated significant differences among sampling months. The minimum and maximum values for the selected factors were, as Cl- 176.2-201.3 g.l-1 , CO2 95-175mg.l-1 , dissolved oxygen (DO) 0.1-2.8 mg.l-1 , HCO3 - 144-496 mg.l-1 , PO42+ 104-875 mg.l-1, NO3- 330-4104 mg.l-1, NO2- 4-21.5 mg.l-1, SO42- 10490-29840 mg.l-1, Ca2+ 561-1606 mg.l-1, Mg2+ 3649-14587 mg.l-1 while water hardness was 21000- 62000 mg.l-1. Fourteen phytoplankton genera included Bacillariophyceae (10 genera),Chlorophyceae (2 genera) and Cyanophyceae (2 genera) were identified during sampling period. The smallest average density of phytoplankton 97249 L-1 was observed in December 2005 and the greatest average density 481983 L-1 in August 2005. Dunaliella sp. composed 92.1% of the lake's phytoplankton. Statistical analysis of phytoplanktons fluctuations showed a significant difference among different months (p〈 0.05).
    Description: Published
    Keywords: Physicochemical ; Phytoplankton
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.368-381
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2021-05-19
    Description: In order to limnological study of Bukan Dam reservoir, sampling was performed monthly from determined sampling sites from April 2013 to March 2014. Sampling was conducted in reservoir lake by a PVC pipe with 2.25 m length and 5 cm diameter by columnar method. Besides, in more dipper (〉5 m) sites, sampling conducted from bottom to surface with 1-m intervals (layer sampling) by a 2-liter Ruttner type sampler. In rivers due to water flow sampling was conducted by a scaled measure. Phytoplankton sampling was performed by 1-liter bottles. Zooplankton was sampled by filtering of 30 L through 55- micron plankton net. These samples were then transferred into bottles and sampling date and the name of station were attached on the bottles. Then, the samples were fixed immediately and transported to laboratory. It should be mentioned some physical parameters were determined in situ. Also, a 2-liter and another 1-liter water were collected to determine chlorophyll a and chemical factors respectively. Samples were preserved in dark and cold place for a week. The upper layers (without phytoplankton) were removed and the lower layer (with phytoplankton) was sampled into 5-ml chambers. The enumeration and identification was performed by a Nikon TS100 inverted microscope with ×400 (Phytoplankton) and ×200 (Zooplankton) magnification according to Utermohl (1958) method. About 50 fields were enumerated for each sample. The comparison of physicochemical and biological factors with standard criterion indicated that the presence of a fertile plain, agricultural growth, drought and higher water demand in recent years, as well as, higher population density, the Saghez city which is the main source of pollution in Bukan dam reservoir has caused that Bukan dam is in the transit state from mesotrophy to eutrophy. The results of the present study suggested that higher trophy in Bukan dam reservoir together with algal high density has negatively affected the Fish life and has reduced the stock in the lake. However, complementary studies should be performed prior to releasing. In this way the problems of other ecosystems should be prevented.
    Description: Iranian Fisheries Science Research Institute
    Description: Published
    Keywords: Limnological ; Plankton ; Eutrophication ; Phytoplankton ; Zooplankton
    Repository Name: AquaDocs
    Type: Report , Refereed
    Format: 82pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    In:  http://aquaticcommons.org/id/eprint/22383 | 18721 | 2018-04-01 19:37:18 | 22383 | Iranian Fisheries Science Research Institute
    Publication Date: 2021-07-04
    Description: Urmia Lake is one of the two large hypersaline lakes in the world which have Artemia. It is located in northwest of Iran. Due to a decrease in water inflow and volume, the salinity of Urmia Lake has reached to more than 300 g.l-1 since 2001. The increased salinity has greatly influenced biological aspects of the lake, and caused the lake undergoes at critical conduction. The aim of the present study was to investigate the distribution fluctuations of phytoplanktons and selected physicochemical factors in relation to Artemia distribution in Urmia Lake during 8 months. Statistical analysis of mean values of ion concentrations and phytoplankton abundance indicated significant differences among sampling months. The minimum and maximum values for the selected factors were, as Cl- 176.2-201.3 g.l-1 , CO2 95-175mg.l-1 , dissolved oxygen (DO) 0.1-2.8 mg.l-1 , HCO3 - 144-496 mg.l-1 , PO42+ 104-875 mg.l-1, NO3- 330-4104 mg.l-1, NO2- 4-21.5 mg.l-1, SO42- 10490-29840 mg.l-1, Ca2+ 561-1606 mg.l-1, Mg2+ 3649-14587 mg.l-1 while water hardness was 21000- 62000 mg.l-1. Fourteen phytoplankton genera included Bacillariophyceae (10 genera),Chlorophyceae (2 genera) and Cyanophyceae (2 genera) were identified during sampling period. The smallest average density of phytoplankton 97249 L-1 was observed in December 2005 and the greatest average density 481983 L-1 in August 2005. Dunaliella sp. composed 92.1% of the lake's phytoplankton. Statistical analysis of phytoplanktons fluctuations showed a significant difference among different months (p〈 0.05).
    Keywords: Biology ; Fisheries ; Limnology ; Urmia Lake ; Physicochemical ; Phytoplankton ; Iran
    Repository Name: AquaDocs
    Type: article , TRUE
    Format: application/pdf
    Format: application/pdf
    Format: 368-381
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    In:  http://aquaticcommons.org/id/eprint/22955 | 18721 | 2018-06-07 20:24:49 | 22955 | Iranian Fisheries Science Research Institute
    Publication Date: 2021-07-11
    Description: The Aras reservoir, located in the north-west of Iran, plays an important role in fisheries, drinking and agricultural water supplies and recreational activities in the region. This study was performed to characterize the seasonal fluctuations of phytoplankton communities and their relationship with environmental factors in the Aras reservoir from August 2013 to May 2014. Sampling was carried out seasonally from 5 sampling locations. In each location three samples were taken for phytoplankton identification and enumeration, chemical analysis and chlorophyll a determination. In total, 72 species belonging to 5 divisions were determined. Cyanobacteria contained the highest density (74%) during the study period with Pseudanabaena limnetica as the most abundant species. This group retained its dominance the whole year round which indicated the poor quality and high nutrient load of the Aras reservoir, mainly due to human activities. On average, Trophic State Index (TSI) showed that water in the reservoir was eu-hypereutrophic. The results indicated that phytoplankton density negatively correlated with Secchi disc depth (R^2 = -0.479), total alkalinity (R^2 = -0.564), total hardness (R^2 = -0.727) and HCO_3 concentration (R^2 = -0.589). On the other hand, there was a positive correlation between the phytoplankton density and TP (R^2 = 0.734). A comparison between the present and a previous study indicated that the cyanobacterial bloom pattern in the Aras reservoir has shifted from warm season toward an all year round cycle which in addition to basin pollution due to anthropogenic activities, can be related to global warming and climate change.
    Keywords: Ecology ; Environment ; Limnology ; Pollution ; Phytoplankton ; Water quality ; Aras reservoir ; Cyanobacteria ; Trophy ; Ecology ; Iran
    Repository Name: AquaDocs
    Type: article , TRUE
    Format: application/pdf
    Format: application/pdf
    Format: 1318-1336
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...