scholarly journals Floristic composition and taxonomic structure of algae in the hyperhaline reservoirs of the northwestern Azov Sea coast (Ukraine)

Algologia ◽  
2020 ◽  
Vol 30 (4) ◽  
pp. 393-405
Author(s):  
A.M. Solonenko ◽  
◽  
O.G. Bren ◽  

The article represents the results of long-term algological studies of hyperhaline reservoirs of the northwestern coast of the Azov Sea. The features of the floristic composition and taxonomic structure of algae in aquatic (water column and bottom), aquatic-terrestrial (water’s edge, dried up water bodies, drying area) and terrestrial (elevated non-flooding areas) habitats of these objects are displayed. A specificity of the studied algoflora lies in the absence of representatives of certain characteristic phyla for the salt-water and non-saline land and water habitats of the territory of Ukraine. It was established that species composition of the studied reservoirs is depleted in comparison with other non-saline and marine ecosystems. Totally, 123 algae species were identified. They represente 7 phyla, 10 classes, 27 orders, 47 families, 68 genera. The largest number of species included three phyla: Cyanoprocaryota – 65 species (52.9% of the total number of identified species), Bacillariophyta – 26 (21.1%), Chlorophyta – 22 (17.9%). The first places among the six leading orders were taken by cyanoprocaryotes from Oscillatoriales, Nostocales, Chroococcales and diatoms from Naviculales. The most numerous species at the family level are trichomous cyanoprocaryotes from Nostocaceae, Pseudanabaenaceae, and Phormidiaceae. There were found 23 leading genera – their species richness exceeds the average indicator (1.81 species). According to the results of original studies, it was noted that all taxonomic levels of algoflora of the hyperhaline reservoirs shows features of not only saline habitats, but also of the freshwater, marine and terrestrial extreme ecosystems. Such diversity of the algal population indicates an unstable hydrological regime and complex relations of water exchange between the hyperhaline reservoirs and nearby terrestrial and aquatic habitats.

Author(s):  
Ekaterina Shchurova ◽  
Ekaterina Shchurova ◽  
Rimma Stanichnaya ◽  
Rimma Stanichnaya ◽  
Sergey Stanichny ◽  
...  

Sivash bay is the shallow-water lagoon of the Azov Sea. Restricted water exchange and high evaporation form Sivash as the basin with very high salinity. This factor leads to different from the Azov Sea thermal and ice regimes of Sivash. Maine aim of the study presented to investigate recent state and changes of the characteristics and processes in the basin using satellite data. Landsat scanners TM, ETM+, OLI, TIRS together with MODIS and AVHRR were used. Additionally NOMADS NOAA and MERRA meteorological data were analyzed. The next topics are discussed in the work: 1. Changes of the sea surface temperature, ice regime and relation with salinity. 2. Coastal line transformation – long term and seasonal, wind impact. 3. Manifestation of the Azov waters intrusions through the Arabat spit, preferable wind conditions.


2020 ◽  
Vol 27 (5) ◽  
Author(s):  
Е. S. Eremina ◽  
V. P. Evstigneev ◽  
◽  
◽  
◽  
...  

Purpose. The work is aimed at studying the components’ intra- and inter-annual variability in the water exchange between the Sivash Bay and the Sea of Azov through the Tonky Strait at the current climatic period based on the empirical conversion schemes and using the hydrometeorological observation data obtained at the nearby stations. Methods and Results. Using the data on the sea level, and the wind direction and speed, the runoffs of the Azov Sea and the Sivash Bay waters in the Tonky Strait during 1966–2013 are calculated by two methods developed by Slatinsky Yu.G. in 1969 and Raskin L.G. in 1992. Predominance of the Azov currents over the Sivash ones is revealed. Seasonal and long-term dynamics of the runoff values in the strait are given based on the monthly average and annual average data. The data on the wind regime variability in the Genichesk region, and the sea level at the Genichesk meteorological station and at the Chongarsky bridge meteorological post are cited. Conclusions. The calculations show that the average annual inflow of the Azov waters through the Tonky Strait varies within the wide range 0.3 km3 – 1.18 km3, and the outflow of the Sivash waters constitutes on average 0.26 km3 per year. Difference between the water inflow and outflow in the strait is characterized by high inter-annual variability. Over the whole period under study, it amounted on average up to 0.45 km3. In the components’ spectrum of water exchange between the Sivash Bay and the Azov Sea, distinguished are the ~ 4 year fluctuations of the Sivash waters outflow from the bay, and the 3 and 5–6 year fluctuations of the Azov Sea waters inflow to the Sivash Bay. Multi-year variability of the Sivash water outflow with the 4 year periodicity is conditioned by the same precipitation amount periodicity over the Sivash Bay.


Algologia ◽  
2020 ◽  
Vol 30 (4) ◽  
pp. 406-420
Author(s):  
O.M. Mironyuk ◽  
◽  
F.P. Tkachenko ◽  

The article presents the results of research on the species diversity of algae of small steppe rivers of the north-western Black Sea coast (NWBS). These are the rivers of Kohylnyk, Chaha, Sarata, Hadjider, Kuchurhan, Yahorlyk, Baraboy, Veliky Kuyalnik, Maly Kuyalnik, Kodyma, Tylihul, Tsarehol, Chichikleya. A total of 329 species (340 infraspecific taxa) of algae belonging to 8 divisions (Bacillariophyta, Cyanobacteria, Chlorophyta, Euglenozoa, Ochrophyta, Charophyta, Dinophyta and Rhodophyta) were identified. The basis of the taxonomic structure of reservoirs are representatives of Bacillariophyta (40%), Cyanobacteria and Chlorophyta (17% each), Charophyta (10.5%), Euglenozoa (10.2%). The total share of other departments is 4.1%. The Tylihul River had the most diverse composition of algae. It is one of the largest small rivers in the region, which dries up every year for a short period. According to the Sørensen-Chekanovsky coefficient, the greatest degree of similarity of the floristic composition of algae was established by pairwise comparison of the rivers of Sarata–Kohylnyk (0.614), Sarata–Hadjider (0.544), and Kohylnyk–Hadjider (0.517). These reservoirs are located in the Danube–Dniester interfluve, have almost the same mineralization and a similar hydrological regime. Among the identified algae species, only 12 are common to all studied rivers. New records for the NWBS were Peranema pleururum Skuja, Phacus platyaulax Pochmann, Monomorphina pyrum (Ehrenberg) Mereschkowsky and Euglena van-goori Deflandre. A rare species Spirulina flavovirens Wisl. was found in in the Kohylnyk River. Anabaena bergii Ostenfeld, Phacus alatus G.A.Klebs, Monomorphina pyrum, Pleurosira laevis (Ehrenberg) Compère, Campylodiscus bicostatus Smith ex Roper, Closterium dianae Ehrenb. ex Ralfs and Batrachospermum gelatinosum (Linnaeus) De Candolle are regionally rare species. In the ecological aspect, the waters of the studied small rivers can be characterized as brackish, poorly flowing, and alkaline. According to the level of organic pollution, they correspond to the β-mesosaprobic zone.


2020 ◽  
Vol 36 (5) ◽  
Author(s):  
Е. S. Eremina ◽  
V. P. Evstigneev ◽  
◽  
◽  

Purpose. The work is aimed at studying the components’ intra- and inter-annual variability in the water exchange between the Sivash Bay and the Sea of Azov through the Tonky Strait at the current climatic period based on the empirical conversion schemes and using the hydrometeorological observation data obtained at the nearby stations. Methods and Results. Using the data on the sea level, and the wind direction and speed, the runoffs of the Azov Sea and the Sivash Bay waters in the Tonky Strait during 1966–2013 are calculated by two methods developed by Slatinsky Yu.G. in 1969 and Raskin L.G. in 1992. Predominance of the Azov currents over the Sivash ones is revealed. Seasonal and long-term dynamics of the runoff values in the strait are given based on the monthly average and annual average data. The data on the wind regime variability in the Genichesk region, and the sea level at the Genichesk meteorological station and at the Chongarsky bridge meteorological post are cited. Conclusions. The calculations show that the average annual inflow of the Azov waters through the Tonky Strait varies within the wide range 0.3 km3 – 1.18 km3, and the outflow of the Sivash waters constitutes on average 0.26 km3 per year. Difference between the water inflow and outflow in the strait is characterized by high inter-annual variability. Over the whole period under study, it amounted on average up to 0.45 km3. In the components’ spectrum of water exchange between the Sivash Bay and the Azov Sea, distinguished are the ~4 year fluctuations of the Sivash waters outflow from the bay, and the 3 and 5–6 year fluctuations of the Azov Sea waters inflow to the Sivash Bay. Multi-year variability of the Sivash water outflow with the 4 year periodicity is conditioned by the same precipitation amount periodicity over the Sivash Bay.


Author(s):  
Ekaterina Shchurova ◽  
Ekaterina Shchurova ◽  
Rimma Stanichnaya ◽  
Rimma Stanichnaya ◽  
Sergey Stanichny ◽  
...  

Sivash bay is the shallow-water lagoon of the Azov Sea. Restricted water exchange and high evaporation form Sivash as the basin with very high salinity. This factor leads to different from the Azov Sea thermal and ice regimes of Sivash. Maine aim of the study presented to investigate recent state and changes of the characteristics and processes in the basin using satellite data. Landsat scanners TM, ETM+, OLI, TIRS together with MODIS and AVHRR were used. Additionally NOMADS NOAA and MERRA meteorological data were analyzed. The next topics are discussed in the work: 1. Changes of the sea surface temperature, ice regime and relation with salinity. 2. Coastal line transformation – long term and seasonal, wind impact. 3. Manifestation of the Azov waters intrusions through the Arabat spit, preferable wind conditions.


2020 ◽  
Vol 16 ◽  
Author(s):  
Lalitha Vivekanandan ◽  
Roxanne Gekonge Mandere ◽  
Sivakumar Thangavel

Background: Constipation is a common, predominant, chronic gastrointestinal functional disorder. The drugs available to treat constipation are limited because of their side effects in long term use. So we need of efficacious drug to treat constipation. Sapindus emarginatus Vahl belongs to the family Sapindaceae, commonly known as soapnut. Traditionally used for the antipruritic, antifertility, constipation, and anti-inflammatory agents. Objective: The present study was undertaken to evaluate the laxative activity of hydroethanolic pericarp extract of Sapindus emarginatus (HESE) in animal models. Methods: The saponin content in extract was measured by gravimetric analysis. The laxative activity of hydroethanolic pericarp extract of Sapindus emarginatus is evaluated by the weight of feces matter, charcoal meal hyperperistalsis test, and loperamide induced constipation model. Results: The saponin content of the soapnut pericarp was 13.48 % and the extract was found to be 11.92 %. The results obtained from these models showed a significant dose-dependent increase in fecal weight, peristalsis index, and moisture content compared to control animals. Conclusion: The present study concluded that the oral administration of HESE showed a significant laxative activity by using different animal models. The presence of triterpene saponins is responsible for this activity. Further studies are needed to confirm their mechanism behind the laxative effect. The administration of extract was found to be a valid candidate in constipation therapy.


Zootaxa ◽  
2011 ◽  
Vol 2794 (1) ◽  
pp. 57 ◽  
Author(s):  
ROBIN KUNDRATA ◽  
LADISLAV BOCAK

Pseudothilmanus Pic, 1918 is redescribed and two species, P. alatus Pic, 1918 and P. marginatus Pic, 1918, are placed in the genus. The subgenus Drilothilmanus Pic, 1918 is synonymized with the nominotypical genus on the basis of low morphological divergence and redundancy in classification. Pseudothilmanus is newly classified in the family Rhagophthalmidae, in contrast to the original placement in Drilidae. Diagnostic characters for Pseudothilmanus and both species placed within the genus are illustrated.


SAGE Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 215824402110223
Author(s):  
Jahanzaib Haider ◽  
Abdul Qayyum ◽  
Zalina Zainudin

This study analyzes the leverage policies of the family and non-family firms of eight East Asian Economies (Hong Kong, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, and Taiwan) by using combined data of 690 family and non-family firms with 3,224 firm–years over the period 2006–2010. This study has used an ordinary least squares (OLS) regression for analyzing the data for the first question, while for the second question, logit regression has been used as the dependent variable (a binary variable). Prior research on family and non-family firms has revealed that family firms issue less (high) debt than non-family firms. Our analysis on a sample of East Asian Economies discloses that family firms have significantly different leverage levels than non-family firms, but their signs are not consistent. On the contrary, when the owner works as CEO/Chairman or member of the Board of Directors, then the family firms issue less debt than the non-family firms. Besides that, this study adds a new question that has not been addressed in the prior studies. The new question has focused on the speed of leverage adjustment. It is found that family firms and non-family firms regarding their debt maturity structure (short-term debt and long-term debt), the speed of leverage adjustments, and their decision to issue securities (i.e., debt vs. equity) are not significantly different. This study concluded that though family firms have a strong influence on each economy, but in South-East Asian countries, leverage policies of the family firms are not much different than that of non-family firms.


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