№ 4 (2021)
Статьи
The variability of morphometric and meristic characteristics of Urmia chub, Petroleuciscus ulanus (Günther, 1899) in the Mahabd-Chai and Godar-Chai rivers, Lake Urmia basin
Аннотация
In this study, for the first time, we provide morphometric and meristic data on Petroleuciscus ulanus from the Lake Urmia basin by comparing them in the populations of the Mahabad-Chai and Godar-Chai rivers. For this purpose, a total of 100 specimens were collected using electrofishing device and cast net during 2014 and 2015. 19 morphometric and 8 meristic traits were measured and counted, respectively. The meristic traits of the two populations showed significant differences in three characters, including branched dorsal and ventral fin rays and lateral line scales (P<0.05). In addition, the morphometric analysis showed significant differences in head length, eye diameter, caudal peduncle length, dorsal fin height and base lengths, pectoral and ventral fin lengths, anal fin base and height lengths (P<0.05). The finding of the current study can help to further studies on the biological features of this endemic species of Iranian inland waters.
1156-1159
Spatial and seasonal variations in the physicochemical parameters of water quality of a tropical reservoir, Nigeria
Аннотация
In this study, the physicochemical properties of a water supply reservoir in the Esa- Odo community, Obokun Local Government Area of Osun State, Nigeria, were determined. Thirteen selected sampling stations over the three reaches of Esa-Odo reservoir along its main axis were monitored between February 2017 to December 2018 with a view to determining the seasonal and spatial variations in the general physicochemical water quality parameters of the reservoir water. From each sampling station, surface water samples were collected bi-monthly for two annual cycles (rainy and dry seasons). The collected water samples were treated and analyzed for physicochemical water quality parameters using standard instrumental and non-instrumental methods. The data obtained were analyzed using appropriate descriptive and inferential statistics. The result of the analyses of the reservoir water showed an increasing clarity from the upstream to the downstream stations with regard to water temperature, depth, transparency, turbidity, and colour. The water was generally near neutral (pH: 7.01 ± 0.04 - 7.07 ± 0.50) but slightly more near neutral in the rainy season than during the dry season. The water in the reservoir can be classified as a dilute salt bicarbonate freshwater with mean conductivity at the three reaches ranging from 113.39 ± 1.67 µScm-1 to 115.24 ± 2.46 µScm-1. Ca2+ and HCO3- were the dominant cation and anion, respectively, at all stations investigated irrespective of seasons of sampling. The mean values of most parameters determined were within permissible limits, making the river water suitable for most probable domestic and industrial uses and livestock support.
1160-1167
Influence of breeding strategy on genetic diversity of individuals
Аннотация
Using a computer simulation model, we tried to investigate how the transition from sexual reproduction to asexual reproduction will affect the population of diploid organisms with a neutral character of molecular evolution. At the same time, special attention was paid to the specificity of microsatellite markers. In this paper, we develop fast and inexpensive methods for assessing the changes in populations that occur with a change in reproductive strategy.
1168-1174