E. E. Dorche, Mojgan Zare Shahraki, O. Farhadian, Y. Keivany
Abstract Zayandehrud Dam Lake located in Isfahan province is the largest lake in central Iran. In this study, the plankton communities including phytoplankton and zooplankton were studied as bioindicator organisms for assessment of water quality in the Zayandehrud Dam Lake. The water and phytoplankton organisms were collected from four stations at different seasons during 2014 by using a Nansen bottle sampler. The zooplankton samples were collected with a plankton net (mesh size = 50 µm). The phytoplankton community was composed of Bacillariophyceae, Cyanophyceae, Euglenophyceae, Dinophyceae and Chrysophyceae. The zooplankton community viz; Cladocera, Rotifera and Copepoda were found to have a density range of 13–155, 21–141 and 11–93 (ind. m−3), respectively. In general, phytoplankton and zooplankton communities, especially the presence of genera such as Cyclotella, Dynobrion, Bosmina and Daphnia (as indices of oligotrophic lakes) and also absence of Microsystis, Brachionus and Lecane are seen as important indices of eutrophic lakes. It could be concluded that the Zayandehrud Dam Lake can be classified as a healthy water body.
{"title":"Seasonal variations of plankton structure as bioindicators in Zayandehrud Dam Lake, Iran","authors":"E. E. Dorche, Mojgan Zare Shahraki, O. Farhadian, Y. Keivany","doi":"10.2478/limre-2018-0017","DOIUrl":"https://doi.org/10.2478/limre-2018-0017","url":null,"abstract":"Abstract Zayandehrud Dam Lake located in Isfahan province is the largest lake in central Iran. In this study, the plankton communities including phytoplankton and zooplankton were studied as bioindicator organisms for assessment of water quality in the Zayandehrud Dam Lake. The water and phytoplankton organisms were collected from four stations at different seasons during 2014 by using a Nansen bottle sampler. The zooplankton samples were collected with a plankton net (mesh size = 50 µm). The phytoplankton community was composed of Bacillariophyceae, Cyanophyceae, Euglenophyceae, Dinophyceae and Chrysophyceae. The zooplankton community viz; Cladocera, Rotifera and Copepoda were found to have a density range of 13–155, 21–141 and 11–93 (ind. m−3), respectively. In general, phytoplankton and zooplankton communities, especially the presence of genera such as Cyclotella, Dynobrion, Bosmina and Daphnia (as indices of oligotrophic lakes) and also absence of Microsystis, Brachionus and Lecane are seen as important indices of eutrophic lakes. It could be concluded that the Zayandehrud Dam Lake can be classified as a healthy water body.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"157 - 165"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47888826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The article presents changes in the course of ice phenomena on Lake Morskie Oko over 50 years. It comprises detailed data of the course of the main parameters of ice regime of the lake in the years 1963–1970. Such a reference period yielded substantial differences in the obtained values of trends in comparison with the period 1971–2010, which is most common in literature. The trends obtained differed substantially from those describing the years 1971–2010, and the change in the parameters – scaled to a year of the analysed period – was about half the size. Attention was also drawn to the practical aspect of the changes in the duration and thickness of ice cover on the lake. In the years 1963–2012 the period of safe movement on the frozen lake was reduced by only 10 days.
{"title":"Changes in the course of ice phenomena on Morskie Oko in the Tatra Mountains from 1963 to 2012 and the implications for tourism","authors":"Bogusław Pawłowski","doi":"10.2478/limre-2018-0018","DOIUrl":"https://doi.org/10.2478/limre-2018-0018","url":null,"abstract":"Abstract The article presents changes in the course of ice phenomena on Lake Morskie Oko over 50 years. It comprises detailed data of the course of the main parameters of ice regime of the lake in the years 1963–1970. Such a reference period yielded substantial differences in the obtained values of trends in comparison with the period 1971–2010, which is most common in literature. The trends obtained differed substantially from those describing the years 1971–2010, and the change in the parameters – scaled to a year of the analysed period – was about half the size. Attention was also drawn to the practical aspect of the changes in the duration and thickness of ice cover on the lake. In the years 1963–2012 the period of safe movement on the frozen lake was reduced by only 10 days.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"167 - 173"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48237631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Pukacz, Małgorzata Oszkinis-Golon, M. Frankowski
Abstract In the vegetation seasons 2016–2017, a survey of 30 pit lakes localized in the eastern part of the Muskau Arch (Western Poland) was carried out. The aim of the study was to characterize the habitat conditions of the selected lakes, based on the physico-chemical water characteristics. We hypothesized that the age and genesis of pit lakes are the main factors responsible for their hydro-chemical diversity. Therefore, in each of the lakes 27 physico-chemical parameters and chlorophyll a were measured in the water surface, in the peak of the vegetation season (July–August). Additionally, they were described in terms of genesis, origin and age. The results showed that the investigated lakes display a high diversity of habitat conditions reflected in varied physico-chemical water properties (significant lake-to-lake differences). The parameters mostly responsible for the differences were: Secchi depth (transparency), pH, EC, colour, hardness, TP, TN, TC, Ca2+, Mg2+, Fe, Al, Mn, S and Chl a. The comparison of the type of excavated aggregate showed significant differences for four parameters only. Much greater differences were found for the genesis of lakes (mining method) – 15 of the 28 analysed parameters significantly differentiated the lakes. Further analysis showed that half of the studied parameters were significantly correlated with the age of the pit lakes. Our results suggest that in addition to natural changes, secondary human-caused transformations (mostly neutralization and fertilization of the water) were among the key factors responsible for the differentiation of the lakes.
{"title":"The physico-chemical diversity of pit lakes of the Muskau Arch (Western Poland) in the context of their evolution and genesis","authors":"A. Pukacz, Małgorzata Oszkinis-Golon, M. Frankowski","doi":"10.2478/limre-2018-0013","DOIUrl":"https://doi.org/10.2478/limre-2018-0013","url":null,"abstract":"Abstract In the vegetation seasons 2016–2017, a survey of 30 pit lakes localized in the eastern part of the Muskau Arch (Western Poland) was carried out. The aim of the study was to characterize the habitat conditions of the selected lakes, based on the physico-chemical water characteristics. We hypothesized that the age and genesis of pit lakes are the main factors responsible for their hydro-chemical diversity. Therefore, in each of the lakes 27 physico-chemical parameters and chlorophyll a were measured in the water surface, in the peak of the vegetation season (July–August). Additionally, they were described in terms of genesis, origin and age. The results showed that the investigated lakes display a high diversity of habitat conditions reflected in varied physico-chemical water properties (significant lake-to-lake differences). The parameters mostly responsible for the differences were: Secchi depth (transparency), pH, EC, colour, hardness, TP, TN, TC, Ca2+, Mg2+, Fe, Al, Mn, S and Chl a. The comparison of the type of excavated aggregate showed significant differences for four parameters only. Much greater differences were found for the genesis of lakes (mining method) – 15 of the 28 analysed parameters significantly differentiated the lakes. Further analysis showed that half of the studied parameters were significantly correlated with the age of the pit lakes. Our results suggest that in addition to natural changes, secondary human-caused transformations (mostly neutralization and fertilization of the water) were among the key factors responsible for the differentiation of the lakes.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"115 - 126"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43889331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammed Missoum Benmeddah, Mohamed Ali Bouzidi, F. Toumi-Benali, Youcef Amar, S. Bouazza, Abbes Dellal, M. Dif
Abstract The objective of this work is firstly an ecobiological study, which aims to determine whether salinity is favorable for a good reproduction rate of cysts in the Artemia salina L., a species known for its use in aquaculture. Secondly, a short-term test of ammonium sulfate toxicity on its vitality is carried out as its environment is permanently subjected to sulphate-laden waste. The work consists of subjecting the species to different salinities in order to produce a good yield in cysts, which once recovered, hatching and breeding is maintained until individuals reach the adult stage. A toxicological study using toxicity test (CL50) is then conducted to study the resistance of these adults with various concentrations of ammonium sulphate. The results obtained from the ecobiological study show a mean similar to the natural environment (p > 0.05) with a favorable concentration for the reproduction of the species at a salinity of about 75 g dm−3. The toxicity test indicates a CL50 equal to 75 mg dm−3 after 24 hours. It is obvious that Artemia salina L. can be cultivated by controlling its reproduction by varying the salinity rate for its use during different seasons of the year, thus ammonium sulphate from waste is considered as a limiting factor.
摘要本工作的目的首先是一项生态生物学研究，旨在确定盐度是否有利于卤虫（Artemia salina L.）囊肿的良好繁殖率。卤虫是一种以在水产养殖中使用而闻名的物种。其次，对硫酸铵的生命力进行了短期毒性测试，因为其环境长期受到硫酸盐废物的影响。这项工作包括将物种置于不同的盐度下，以在包囊中产生良好的产量，包囊一旦恢复，孵化和繁殖将一直维持到个体达到成年阶段。然后使用毒性试验（CL50）进行毒理学研究，以研究这些成虫对不同浓度硫酸铵的抗性。从生态生物学研究中获得的结果显示，平均值与自然环境相似（p>0.05），在盐度约为75 g dm−3的条件下，物种繁殖的浓度有利。毒性测试表明24小时后CL50等于75 mg dm−3。很明显，盐卤虫可以通过在一年中的不同季节改变盐度来控制其繁殖来进行养殖，因此废物中的硫酸铵被认为是一个限制因素。
{"title":"Ecobiological study of Artemia salina L. and first determination of the toxicity of ammonium sulphate","authors":"Mohammed Missoum Benmeddah, Mohamed Ali Bouzidi, F. Toumi-Benali, Youcef Amar, S. Bouazza, Abbes Dellal, M. Dif","doi":"10.2478/limre-2018-0012","DOIUrl":"https://doi.org/10.2478/limre-2018-0012","url":null,"abstract":"Abstract The objective of this work is firstly an ecobiological study, which aims to determine whether salinity is favorable for a good reproduction rate of cysts in the Artemia salina L., a species known for its use in aquaculture. Secondly, a short-term test of ammonium sulfate toxicity on its vitality is carried out as its environment is permanently subjected to sulphate-laden waste. The work consists of subjecting the species to different salinities in order to produce a good yield in cysts, which once recovered, hatching and breeding is maintained until individuals reach the adult stage. A toxicological study using toxicity test (CL50) is then conducted to study the resistance of these adults with various concentrations of ammonium sulphate. The results obtained from the ecobiological study show a mean similar to the natural environment (p > 0.05) with a favorable concentration for the reproduction of the species at a salinity of about 75 g dm−3. The toxicity test indicates a CL50 equal to 75 mg dm−3 after 24 hours. It is obvious that Artemia salina L. can be cultivated by controlling its reproduction by varying the salinity rate for its use during different seasons of the year, thus ammonium sulphate from waste is considered as a limiting factor.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"109 - 113"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46698143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The dimensions of many water streams, which satisfy proper hydraulic conditions, may not be compatible with the designed dimensions of an irrigation work that needs to be constructed in some locations. The design requirements of such irrigation works may involve a contraction in the channel width in the required location. This contraction, of course, affects different flow properties and the scour hole formed downstream of these structures. Therefore, the present experimental study aims to investigate the effect of the transition angle and the contraction on the flow properties and on the scour phenomenon downstream water structures. Through 460 experimental runs, carried out on 20 experimental models, the study proved that, for an efficient hydraulic performance and economic design, the best transition angle (θ) for the approaches of water structures is 30° with a relative contracted width ratio (r = b/B) not less than 0.6.
{"title":"Effect of canal width contraction on the hydraulic parameters and scour downstream water structures","authors":"M. Ashour, Tawab E. Aly, Mahmoud M. Mostafa","doi":"10.2478/limre-2018-0010","DOIUrl":"https://doi.org/10.2478/limre-2018-0010","url":null,"abstract":"Abstract The dimensions of many water streams, which satisfy proper hydraulic conditions, may not be compatible with the designed dimensions of an irrigation work that needs to be constructed in some locations. The design requirements of such irrigation works may involve a contraction in the channel width in the required location. This contraction, of course, affects different flow properties and the scour hole formed downstream of these structures. Therefore, the present experimental study aims to investigate the effect of the transition angle and the contraction on the flow properties and on the scour phenomenon downstream water structures. Through 460 experimental runs, carried out on 20 experimental models, the study proved that, for an efficient hydraulic performance and economic design, the best transition angle (θ) for the approaches of water structures is 30° with a relative contracted width ratio (r = b/B) not less than 0.6.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"101 - 93"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44554648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This article is an attempt to analyse and compare several selected parameters regarding ice phenomena using the correlation analysis of two lakes, which are benchmark lakes located in the central part of the Kashubian Lakeland. These lakes are: Raduńskie Górne, a larger one (387.2 hm2) and Ostrzyckie, a smaller one covering an area of 308.0 hm2. The analysis covered measurement sequences for the period 1971–2010. The material for analysis regarding data on ice phenomena on Lake Raduńskie Górne was obtained from the University of Gdańsk Limnological Station in Borucino while the data for Lake Ostrzyckie was obtained from the Institute of Meteorology and Water Management (IMGW). Relations between the following parameters of the ice regime were analysed: duration of the ice phenomena, duration of the ice cover, average and maximum thickness of the ice cover. The analysis and data comparisons have revealed that there are strong and very strong relations between the analysed parameters, which made it possible to develop proper statistical models. Hence, should there be a lack of data on the ice-cover pattern for one of these lakes it is possible to recreate them using the elaborated empirical models and data for the other.
{"title":"The statistical relation/coherence between ice-regimes of Lake Raduńskie Górne and Lake Ostrzyckie","authors":"J. Barańczuk","doi":"10.2478/limre-2018-0011","DOIUrl":"https://doi.org/10.2478/limre-2018-0011","url":null,"abstract":"Abstract This article is an attempt to analyse and compare several selected parameters regarding ice phenomena using the correlation analysis of two lakes, which are benchmark lakes located in the central part of the Kashubian Lakeland. These lakes are: Raduńskie Górne, a larger one (387.2 hm2) and Ostrzyckie, a smaller one covering an area of 308.0 hm2. The analysis covered measurement sequences for the period 1971–2010. The material for analysis regarding data on ice phenomena on Lake Raduńskie Górne was obtained from the University of Gdańsk Limnological Station in Borucino while the data for Lake Ostrzyckie was obtained from the Institute of Meteorology and Water Management (IMGW). Relations between the following parameters of the ice regime were analysed: duration of the ice phenomena, duration of the ice cover, average and maximum thickness of the ice cover. The analysis and data comparisons have revealed that there are strong and very strong relations between the analysed parameters, which made it possible to develop proper statistical models. Hence, should there be a lack of data on the ice-cover pattern for one of these lakes it is possible to recreate them using the elaborated empirical models and data for the other.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"103 - 108"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41567287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The paper presents analysis results concerning changes in the range of areas of surface and transitional retention, here corresponding with wetlands, in two small lake catchments in the western part of West Polesie. The cartometric research was performed on maps covering the period from the 19th to the early 21st century. The analyses were referred to the modern state of investigation recorded on orthophotomaps in data bases disclosed in Geoportal Krajowy and in the Google Earth Pro application. Lake surface retention showed no substantial changes, and the differences result from the scale of maps used in the study, and therefore from the degree of detail of the presented objects. In the catchment of Lake Czarne Gościnieckie it occupied from 13.61 to 15.64% of its area, and in the catchment of Lake Brzeziczno from 0.96 to 1.28%. The greatest discrepancies in the area of wetlands result from the cartographic method of presentation, and generalisation of maps. In the catchment of Lake Czarne Gościnieckie, areas of transitional retention could be identified on 11 out of 13 maps, and in the catchment of Lake Brzeziczno on 12. In the case of the former catchment, transitional retention occupies from 17.35 to 34.00% of its area, and in the catchment of Brzeziczno from 4.81 to 24.00%. Such different surface areas of wetlands measured on maps, however, do not signify evident tendencies for change. Over the last 200 years, no substantial changes occurred in the studied catchments regarding the range of surface waters and wetlands, as confirmed by field research conducted in the years 2006-2012. The quantity and quality of maps and the variability of their scales encourage a careful interpretation of obtained information. In such a case, it is necessary to supplement cartographic analyses with investigating procedures of map preparation, and also to collect written documents concerning the entire area.
{"title":"Analysis of Water Retention Changes in Selected Lake-Wetland Catchments of West Polesie Based on Historical Documents","authors":"Katarzyna Mięsiak-Wójcik","doi":"10.2478/limre-2018-0007","DOIUrl":"https://doi.org/10.2478/limre-2018-0007","url":null,"abstract":"Abstract The paper presents analysis results concerning changes in the range of areas of surface and transitional retention, here corresponding with wetlands, in two small lake catchments in the western part of West Polesie. The cartometric research was performed on maps covering the period from the 19th to the early 21st century. The analyses were referred to the modern state of investigation recorded on orthophotomaps in data bases disclosed in Geoportal Krajowy and in the Google Earth Pro application. Lake surface retention showed no substantial changes, and the differences result from the scale of maps used in the study, and therefore from the degree of detail of the presented objects. In the catchment of Lake Czarne Gościnieckie it occupied from 13.61 to 15.64% of its area, and in the catchment of Lake Brzeziczno from 0.96 to 1.28%. The greatest discrepancies in the area of wetlands result from the cartographic method of presentation, and generalisation of maps. In the catchment of Lake Czarne Gościnieckie, areas of transitional retention could be identified on 11 out of 13 maps, and in the catchment of Lake Brzeziczno on 12. In the case of the former catchment, transitional retention occupies from 17.35 to 34.00% of its area, and in the catchment of Brzeziczno from 4.81 to 24.00%. Such different surface areas of wetlands measured on maps, however, do not signify evident tendencies for change. Over the last 200 years, no substantial changes occurred in the studied catchments regarding the range of surface waters and wetlands, as confirmed by field research conducted in the years 2006-2012. The quantity and quality of maps and the variability of their scales encourage a careful interpretation of obtained information. In such a case, it is necessary to supplement cartographic analyses with investigating procedures of map preparation, and also to collect written documents concerning the entire area.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"59 - 75"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44028884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Szeląg-Wasielewska, Maria Pajchrowska, B. Mądrecka, J. Józefiak
Abstract The unicellular flagellates of the genus Phacotus, which form a solid calcite lorica by extracellular precipitation of calcium carbonate are some of the nanoplankters quite frequently occurring in hardwater ecosystems of the temperate zone. The aim of this study was to describe seasonal changes of Phacotus lenticularis populations in several types of water bodies (a glacial lake, small and shallow ponds, and a lowland river) in relation to some environmental parameters. All the water bodies are subject to multiple human pressure: recreation, fishing, agriculture, and urbanization. P. lenticularis individuals preserved in Lugol’s solution were counted under an inverted microscope (after sedimentation in 14 or 9 ml chambers), including both empty and filled loricae. Its populations differed both between seasons and between waters. High P. lenticularis abundance was mainly limited to the summer months. It was observed at temperatures above 19°C and pH values above 7.8, in water characterized by quite high electrolytic conductivity (>500 μS cm-1). Statistical analysis reveals two significant relationships between physicochemical parameters and the abundance of P. lenticularis. This suggests that in the investigated waters the biotic factors and processes are probably more important regulators of changes in the density of its population than nutrients.
{"title":"Seasonal Variation of the Calcifying Green Alga Phacotus Lenticularis (Ehrenb.) Stein in Water Bodies under Human Influence (Mid-Western Poland)","authors":"E. Szeląg-Wasielewska, Maria Pajchrowska, B. Mądrecka, J. Józefiak","doi":"10.2478/limre-2018-0009","DOIUrl":"https://doi.org/10.2478/limre-2018-0009","url":null,"abstract":"Abstract The unicellular flagellates of the genus Phacotus, which form a solid calcite lorica by extracellular precipitation of calcium carbonate are some of the nanoplankters quite frequently occurring in hardwater ecosystems of the temperate zone. The aim of this study was to describe seasonal changes of Phacotus lenticularis populations in several types of water bodies (a glacial lake, small and shallow ponds, and a lowland river) in relation to some environmental parameters. All the water bodies are subject to multiple human pressure: recreation, fishing, agriculture, and urbanization. P. lenticularis individuals preserved in Lugol’s solution were counted under an inverted microscope (after sedimentation in 14 or 9 ml chambers), including both empty and filled loricae. Its populations differed both between seasons and between waters. High P. lenticularis abundance was mainly limited to the summer months. It was observed at temperatures above 19°C and pH values above 7.8, in water characterized by quite high electrolytic conductivity (>500 μS cm-1). Statistical analysis reveals two significant relationships between physicochemical parameters and the abundance of P. lenticularis. This suggests that in the investigated waters the biotic factors and processes are probably more important regulators of changes in the density of its population than nutrients.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"83 - 89"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42061952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Kirvel, Mikhail Kukshinov, A. Volchek, P. Kirvel
Abstract The article concerns the study of the influence of river reservoirs of Belarus on the evolution of river channels in their downstream pools. On the basis of observational data from the Republican Hydrometeorological Center of the Republic of Belarus (RHMC), as well as own field observations a quantitative evaluation of the change of the main channel formation factors, the direction, horizontal and vertical parameters of deformation of the riverbeds below dams has been performed. Changes in the type of channel processes for the regulated parts of rivers have also been assessed. It has been found that the investigated reservoirs accumulate up to 65% of the sediment transported by the river in a suspended state. Restoration of the water turbidity to values close to the natural regime occurs at a distance of 20 km downstream from a dam of small reservoirs, and up to 50 km downstream from a dam in the case of medium-sized reservoirs. The degree of the riverbed deformations downstream from a reservoir is defined by the geological and lithologic structure of the channel bottom deposits. If there are easily washed sand deposits at the bottom, then the dominant process is deep erosion. If sediments are more heterogenic with increased admixture of gravel-pebble material the development of directed deep erosion is reduced. The change of the existing type of channel processes of regulated rivers is due to the imbalance between the main factors of channel formation in the initial period of the operation of new water-engineering systems (5-7 years). The observed changes are typical of rivers with sandy riverbed.
{"title":"Channel Formation in Rivers Downstream of Water Reservoirs","authors":"I. Kirvel, Mikhail Kukshinov, A. Volchek, P. Kirvel","doi":"10.2478/limre-2018-0006","DOIUrl":"https://doi.org/10.2478/limre-2018-0006","url":null,"abstract":"Abstract The article concerns the study of the influence of river reservoirs of Belarus on the evolution of river channels in their downstream pools. On the basis of observational data from the Republican Hydrometeorological Center of the Republic of Belarus (RHMC), as well as own field observations a quantitative evaluation of the change of the main channel formation factors, the direction, horizontal and vertical parameters of deformation of the riverbeds below dams has been performed. Changes in the type of channel processes for the regulated parts of rivers have also been assessed. It has been found that the investigated reservoirs accumulate up to 65% of the sediment transported by the river in a suspended state. Restoration of the water turbidity to values close to the natural regime occurs at a distance of 20 km downstream from a dam of small reservoirs, and up to 50 km downstream from a dam in the case of medium-sized reservoirs. The degree of the riverbed deformations downstream from a reservoir is defined by the geological and lithologic structure of the channel bottom deposits. If there are easily washed sand deposits at the bottom, then the dominant process is deep erosion. If sediments are more heterogenic with increased admixture of gravel-pebble material the development of directed deep erosion is reduced. The change of the existing type of channel processes of regulated rivers is due to the imbalance between the main factors of channel formation in the initial period of the operation of new water-engineering systems (5-7 years). The observed changes are typical of rivers with sandy riverbed.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"47 - 57"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69228788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This article presents the hydrographic and hydrochemical characteristics of this lake. Lake Jazerske is located in the Western Carpathians (Spiš Magura) in northern Slovakia. It occupies a depression that was formed at the foot of the main scarp of a landslide. Below the lake, there are small intercolluvial depressions that have been transformed into wetlands (peat bogs). The studied lake is very small. Its area is 3600 m2 and its length is 85 m. The maximum depth of the lake is 7.2 m and its capacity is 17 000 m3. The lake is supplied by an inflow of groundwater via fractured aquifers. During periods of heavy rainfall and snow melting, the lake is also supplied by the water from surface runoff. On the main slope of the landslides, traces of ephemeral courses were also found. During the periods of increased supply (spring snow melting, summer rainfall), the outflow of water from the lake occurs both on the surface and underground. In terms of its hydrochemistry, the lake water represents the four-ion type - bicarbonate-sulphate-calcium-magnesium. The concentrations of various ions is characteristic of the shallow groundwater of the Carpathian flysch. The predominant cation, the average concentration of which is 52 mg dm-3, is calcium. The dominant anion is carbohydrates with an average concentration of 163 mg dm-3. What is interesting is the very low levels of chlorides, which do not exceed 2 mg dm-3. The electrolytic conductivity of the water flowing out of the lake ranged from 290 to 328 μS cm-1.
{"title":"Hydrographic And Hydrochemical Characteristics of the Landslide Lake Jazerske (Spišska Magura, Northern Slovakia)","authors":"T. Molenda","doi":"10.2478/limre-2018-0008","DOIUrl":"https://doi.org/10.2478/limre-2018-0008","url":null,"abstract":"Abstract This article presents the hydrographic and hydrochemical characteristics of this lake. Lake Jazerske is located in the Western Carpathians (Spiš Magura) in northern Slovakia. It occupies a depression that was formed at the foot of the main scarp of a landslide. Below the lake, there are small intercolluvial depressions that have been transformed into wetlands (peat bogs). The studied lake is very small. Its area is 3600 m2 and its length is 85 m. The maximum depth of the lake is 7.2 m and its capacity is 17 000 m3. The lake is supplied by an inflow of groundwater via fractured aquifers. During periods of heavy rainfall and snow melting, the lake is also supplied by the water from surface runoff. On the main slope of the landslides, traces of ephemeral courses were also found. During the periods of increased supply (spring snow melting, summer rainfall), the outflow of water from the lake occurs both on the surface and underground. In terms of its hydrochemistry, the lake water represents the four-ion type - bicarbonate-sulphate-calcium-magnesium. The concentrations of various ions is characteristic of the shallow groundwater of the Carpathian flysch. The predominant cation, the average concentration of which is 52 mg dm-3, is calcium. The dominant anion is carbohydrates with an average concentration of 163 mg dm-3. What is interesting is the very low levels of chlorides, which do not exceed 2 mg dm-3. The electrolytic conductivity of the water flowing out of the lake ranged from 290 to 328 μS cm-1.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"18 1","pages":"77 - 81"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41457534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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