The endangered endemic species Sevan trout (Salmo ischchan Kessler, 1877) is under the threat of ... more The endangered endemic species Sevan trout (Salmo ischchan Kessler, 1877) is under the threat of extinction and its survival is dependent on restocking by smolts. Thus, there is an urgent need to find an effective solution for restocking wild populations. After developing a theoretical methodology to reveal the most suitable parts of spawning rivers for natural reproduction, we consider the incubation of eggs in the wild as an appropriate method for the validation of the results of the theoretical assessment. Thus, we estimate the eggs’ survival differences in the wild and microcosm conditions which found significant differences in the sac-fry emergence rate in the zones assessed as “partly suitable” and “unsuitable”. Also, the results show that the emergence of eggs in the wild was less than in the microcosm conditions and the success rate of emergence of eyed eggs in the wild was higher than that of the green eggs. The results of one-way ANOVA, correlation and general linear mixed...
potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the si... more potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the significance of changes in the quantitative parameters of phytoplankton development within years with the peak in 2018. Some antagonistic relations between the groups of phytoplankton under the HAB events were also shown through factorial and correlation analysis. Spatial interpolations revealed very limited extents of HABs compared with "blooms" led by Bacillariophyta species. HABs were mainly occurring in the littoral zone in a close proximity to the estuaries of Lake Sevan major tributaries.
The Marmarik River is the largest tributary of the Hrazdan River. However, it is heavily isolated... more The Marmarik River is the largest tributary of the Hrazdan River. However, it is heavily isolated from the main course of the river by the Aghbyurak dam. Considering low density of population and lack of pollution sources in the basin, the Marmarik River valley is a well-known biodiversity area within Armenia. As in many small tributaries, there is a limited knowledge about the ichthyofauna and its spatial distribution in the drainage basin. Thus, the aim of the study was to reveal the species structure and spatial distribution of fish in the Marmarik River. The results show five species of fish permanently dwelling the river where the most abundant one is the Kura chub and the rarest species is Khramicarp. Limited distribution was revealed also for Brown trout and Berg loach.
Complex studies of seasonal differences of the ecological state of Masrik River (Armenia) were re... more Complex studies of seasonal differences of the ecological state of Masrik River (Armenia) were realized in 2017. Water quality was assessed by BMWP, ASPT and FBI indices based on studies of qualitative and quantitative structures of benthic macro-invertebrates. Potential reference sites in the basin were revealed using the %EPT taxa index in addition to water quality assessment by bioindication methods as well as hydro-chemical, -physical and -morphological measurements. The applicability of the used biotic indices for the different parts of Masrik River was discussed.
potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the si... more potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the significance of changes in the quantitative parameters of phytoplankton development within years with the peak in 2018. Some antagonistic relations between the groups of phytoplankton under the HAB events were also shown through factorial and correlation analysis. Spatial interpolations revealed very limited extents of HABs compared with "blooms" led by Bacillariophyta species. HABs were mainly occurring in the littoral zone in a close proximity to the estuaries of Lake Sevan major tributaries.
The improvement of water management calls for action in the Republic of Armenia. Nowadays, the de... more The improvement of water management calls for action in the Republic of Armenia. Nowadays, the development of the hydrobiological monitoring approaches and procedures is the main goal. However, a lack of knowledge on the background conditions prevents further activities of revaluating of the methods used for water monitoring in Armenia with the EU WFD principles. Following the results of baseline studies conducted in the Debed River system, it was concluded to investigate small tributaries in order to find the most relevant and the best available site in the drainage basin. The study aims to analyse the community of benthic macroinvertebrates of the Tandzut River. We suggest the Tandzut River as a relevant substitution for the recent best available site in the area due to the ecological status of the upper reaches of the Tandzut River, which is by one category higher than the recent best available site of the Pambak River system according to BMWP index.
The improvement of water management calls for action in the Republic of Armenia. Nowadays, the de... more The improvement of water management calls for action in the Republic of Armenia. Nowadays, the development of the hydrobiological monitoring approaches and procedures is the main goal. However, a lack of knowledge on the background conditions prevents further activities of revaluating of the methods used for water monitoring in Armenia with the EU WFD principles. Following the results of baseline studies conducted in the Debed River system, it was concluded to investigate small tributaries in order to find the most relevant and the best available site in the drainage basin. The study aims to analyse the community of benthic macroinvertebrates of the Tandzut River. We suggest the Tandzut River as a relevant substitution for the recent best available site in the area due to the ecological status of the upper reaches of the Tandzut River, which is by one category higher than the recent best available site of the Pambak River system according to BMWP index.
The Government of the Republic of Armenia (RA) strives to ensure the measures to achieve good eco... more The Government of the Republic of Armenia (RA) strives to ensure the measures to achieve good ecological status for Armenian surface water bodies. However, the main goal remains unaccomplished, as the hydro-biological monitoring tools are not properly developed. Thus, the current work aims at contributing to the establishment of principles and a relevant and cost-effective biological monitoring tool for the RA aquatic ecosystems, through the development of a simplified multimetric index (MMI). Since the adoption of the decree N° 927-N from 11 Jun 2011, the baseline studies have been initiated in the six river basin management areas established in the RA. The current work is summing up the results for the Arpa River system in order to test the methodology. In particular, it is testing the possibility to develop MMI based on the use of Rapid Biological Assessment protocol accepted in our monitoring system. Also, the work represents the approach of bottom-up biotic validation of refere...
Endemic fish species of Armenian ichthyofauna—Sevan trout (Salmo ischchan Kessler, 1877)—is regis... more Endemic fish species of Armenian ichthyofauna—Sevan trout (Salmo ischchan Kessler, 1877)—is registered in the Red Book of Animals of the Republic of Armenia as “Critically Endangered” (corresponds to IUCN category: CR A2cd). Its natural reproduction hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the Lake Sevan drainage basin.Masrik River is formerly known as a spawning river for two ecological races of the Sevan trout, but there is no up-to-date and in-depth studies of its potential to support natural reproduction. Thus, a set of spawning criteria was arranged as matrix and state of Masrik River as spawning area for the Sevan trout was assessed. The results showed that the potential of different parts of Masrik River to support natural reproduction of Sevan trout varied from quite appropriate to inappropriate. The main limiting factors revealed were water temperature, velocity and substrate conditions.
Vestnik of Astrakhan State Technical University. Series: Fishing industry
Endemic fish species of Armenian ichthyofauna – the Sevan trout (Salmo ischchan, Kessler, 1877) i... more Endemic fish species of Armenian ichthyofauna – the Sevan trout (Salmo ischchan, Kessler, 1877) is registered in the Red Book of Animals of the Republic of Armenia as critically endangered (corresponds to IUCN category: CR A2cd). Its natural reproduction hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the drainage basin of Lake Sevan. The Lichq River is formerly known as a spawning river for two ecological races of Sevan trout, but because of different factors there are no more wild populations of Sevan trout spawning. The aim of the study was checking the efficiency of two methods of egg incubation in the Lichq River for restoration of Gegarkuni population. The experiments were carried out with newly fertilized and eyed eggs of Gegarkuni in the same periods and in the same areas to avoid the unforeseen effects of environmental factors on assessment. The results showed that the mortality rate of green eggs in the natural...
The endangered endemic species Sevan trout (Salmo ischchan Kessler, 1877) is under the threat of ... more The endangered endemic species Sevan trout (Salmo ischchan Kessler, 1877) is under the threat of extinction and its survival is dependent on restocking by smolts. Thus, there is an urgent need to find an effective solution for restocking wild populations. After developing a theoretical methodology to reveal the most suitable parts of spawning rivers for natural reproduction, we consider the incubation of eggs in the wild as an appropriate method for the validation of the results of the theoretical assessment. Thus, we estimate the eggs’ survival differences in the wild and microcosm conditions which found significant differences in the sac-fry emergence rate in the zones assessed as “partly suitable” and “unsuitable”. Also, the results show that the emergence of eggs in the wild was less than in the microcosm conditions and the success rate of emergence of eyed eggs in the wild was higher than that of the green eggs. The results of one-way ANOVA, correlation and general linear mixed...
potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the si... more potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the significance of changes in the quantitative parameters of phytoplankton development within years with the peak in 2018. Some antagonistic relations between the groups of phytoplankton under the HAB events were also shown through factorial and correlation analysis. Spatial interpolations revealed very limited extents of HABs compared with "blooms" led by Bacillariophyta species. HABs were mainly occurring in the littoral zone in a close proximity to the estuaries of Lake Sevan major tributaries.
The Marmarik River is the largest tributary of the Hrazdan River. However, it is heavily isolated... more The Marmarik River is the largest tributary of the Hrazdan River. However, it is heavily isolated from the main course of the river by the Aghbyurak dam. Considering low density of population and lack of pollution sources in the basin, the Marmarik River valley is a well-known biodiversity area within Armenia. As in many small tributaries, there is a limited knowledge about the ichthyofauna and its spatial distribution in the drainage basin. Thus, the aim of the study was to reveal the species structure and spatial distribution of fish in the Marmarik River. The results show five species of fish permanently dwelling the river where the most abundant one is the Kura chub and the rarest species is Khramicarp. Limited distribution was revealed also for Brown trout and Berg loach.
Complex studies of seasonal differences of the ecological state of Masrik River (Armenia) were re... more Complex studies of seasonal differences of the ecological state of Masrik River (Armenia) were realized in 2017. Water quality was assessed by BMWP, ASPT and FBI indices based on studies of qualitative and quantitative structures of benthic macro-invertebrates. Potential reference sites in the basin were revealed using the %EPT taxa index in addition to water quality assessment by bioindication methods as well as hydro-chemical, -physical and -morphological measurements. The applicability of the used biotic indices for the different parts of Masrik River was discussed.
potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the si... more potentially toxic. Univariate analysis of variance with the post hoc Tukey test has proved the significance of changes in the quantitative parameters of phytoplankton development within years with the peak in 2018. Some antagonistic relations between the groups of phytoplankton under the HAB events were also shown through factorial and correlation analysis. Spatial interpolations revealed very limited extents of HABs compared with "blooms" led by Bacillariophyta species. HABs were mainly occurring in the littoral zone in a close proximity to the estuaries of Lake Sevan major tributaries.
The improvement of water management calls for action in the Republic of Armenia. Nowadays, the de... more The improvement of water management calls for action in the Republic of Armenia. Nowadays, the development of the hydrobiological monitoring approaches and procedures is the main goal. However, a lack of knowledge on the background conditions prevents further activities of revaluating of the methods used for water monitoring in Armenia with the EU WFD principles. Following the results of baseline studies conducted in the Debed River system, it was concluded to investigate small tributaries in order to find the most relevant and the best available site in the drainage basin. The study aims to analyse the community of benthic macroinvertebrates of the Tandzut River. We suggest the Tandzut River as a relevant substitution for the recent best available site in the area due to the ecological status of the upper reaches of the Tandzut River, which is by one category higher than the recent best available site of the Pambak River system according to BMWP index.
The improvement of water management calls for action in the Republic of Armenia. Nowadays, the de... more The improvement of water management calls for action in the Republic of Armenia. Nowadays, the development of the hydrobiological monitoring approaches and procedures is the main goal. However, a lack of knowledge on the background conditions prevents further activities of revaluating of the methods used for water monitoring in Armenia with the EU WFD principles. Following the results of baseline studies conducted in the Debed River system, it was concluded to investigate small tributaries in order to find the most relevant and the best available site in the drainage basin. The study aims to analyse the community of benthic macroinvertebrates of the Tandzut River. We suggest the Tandzut River as a relevant substitution for the recent best available site in the area due to the ecological status of the upper reaches of the Tandzut River, which is by one category higher than the recent best available site of the Pambak River system according to BMWP index.
The Government of the Republic of Armenia (RA) strives to ensure the measures to achieve good eco... more The Government of the Republic of Armenia (RA) strives to ensure the measures to achieve good ecological status for Armenian surface water bodies. However, the main goal remains unaccomplished, as the hydro-biological monitoring tools are not properly developed. Thus, the current work aims at contributing to the establishment of principles and a relevant and cost-effective biological monitoring tool for the RA aquatic ecosystems, through the development of a simplified multimetric index (MMI). Since the adoption of the decree N° 927-N from 11 Jun 2011, the baseline studies have been initiated in the six river basin management areas established in the RA. The current work is summing up the results for the Arpa River system in order to test the methodology. In particular, it is testing the possibility to develop MMI based on the use of Rapid Biological Assessment protocol accepted in our monitoring system. Also, the work represents the approach of bottom-up biotic validation of refere...
Endemic fish species of Armenian ichthyofauna—Sevan trout (Salmo ischchan Kessler, 1877)—is regis... more Endemic fish species of Armenian ichthyofauna—Sevan trout (Salmo ischchan Kessler, 1877)—is registered in the Red Book of Animals of the Republic of Armenia as “Critically Endangered” (corresponds to IUCN category: CR A2cd). Its natural reproduction hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the Lake Sevan drainage basin.Masrik River is formerly known as a spawning river for two ecological races of the Sevan trout, but there is no up-to-date and in-depth studies of its potential to support natural reproduction. Thus, a set of spawning criteria was arranged as matrix and state of Masrik River as spawning area for the Sevan trout was assessed. The results showed that the potential of different parts of Masrik River to support natural reproduction of Sevan trout varied from quite appropriate to inappropriate. The main limiting factors revealed were water temperature, velocity and substrate conditions.
Vestnik of Astrakhan State Technical University. Series: Fishing industry
Endemic fish species of Armenian ichthyofauna – the Sevan trout (Salmo ischchan, Kessler, 1877) i... more Endemic fish species of Armenian ichthyofauna – the Sevan trout (Salmo ischchan, Kessler, 1877) is registered in the Red Book of Animals of the Republic of Armenia as critically endangered (corresponds to IUCN category: CR A2cd). Its natural reproduction hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the drainage basin of Lake Sevan. The Lichq River is formerly known as a spawning river for two ecological races of Sevan trout, but because of different factors there are no more wild populations of Sevan trout spawning. The aim of the study was checking the efficiency of two methods of egg incubation in the Lichq River for restoration of Gegarkuni population. The experiments were carried out with newly fertilized and eyed eggs of Gegarkuni in the same periods and in the same areas to avoid the unforeseen effects of environmental factors on assessment. The results showed that the mortality rate of green eggs in the natural...
Uploads
Papers by Vardan Asatryan
Animals of the Republic of Armenia as “Critically Endangered” (corresponds to IUCN category: CR A2cd). Its natural reproduction
hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the Lake
Sevan drainage basin.Masrik River is formerly known as a spawning river for two ecological races of the Sevan trout, but there is
no up-to-date and in-depth studies of its potential to support natural reproduction. Thus, a set of spawning criteria was arranged as
matrix and state of Masrik River as spawning area for the Sevan trout was assessed. The results showed that the potential of
different parts of Masrik River to support natural reproduction of Sevan trout varied from quite appropriate to inappropriate. The
main limiting factors revealed were water temperature, velocity and substrate conditions.
Animals of the Republic of Armenia as “Critically Endangered” (corresponds to IUCN category: CR A2cd). Its natural reproduction
hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the Lake
Sevan drainage basin.Masrik River is formerly known as a spawning river for two ecological races of the Sevan trout, but there is
no up-to-date and in-depth studies of its potential to support natural reproduction. Thus, a set of spawning criteria was arranged as
matrix and state of Masrik River as spawning area for the Sevan trout was assessed. The results showed that the potential of
different parts of Masrik River to support natural reproduction of Sevan trout varied from quite appropriate to inappropriate. The
main limiting factors revealed were water temperature, velocity and substrate conditions.