Abstract The paper discusses the impact of lake morphometric parameters on the thermal structure of water during the period of summer stagnation. The summer period in the lakes is characterized by clearly expressed properties of the thermal structure of water, differentiating lakes from one another. The study was carried out on 141 lakes in northern Poland, for which at least 3 vertical water temperature measurements were taken in different years. They showed a significant influence of lake basin morphometry upon the thermal structure of water in lakes. In general, measurements of the vertical distribution of water temperature showed clear diversity, and depending on the depth also thermal layers (epi-, meta- and hypolimnion). The results of the analysis of 8 lake morphometric parameters and 10 thermal stratification parameters revealed the existence of significant dependencies between them. The best-preserved relations (statistically significant) occurred between the parameters characterizing the lake depth and meta- and hypolimnion properties, as well as the thermal stratification factor and heat content in a unit of volume.
{"title":"Thermal Structure of Water During the Summer in Lakes of the Polish Lowlands as a Result of their Varied Morphometry","authors":"R. Skowron","doi":"10.2478/limre-2020-0010","DOIUrl":"https://doi.org/10.2478/limre-2020-0010","url":null,"abstract":"Abstract The paper discusses the impact of lake morphometric parameters on the thermal structure of water during the period of summer stagnation. The summer period in the lakes is characterized by clearly expressed properties of the thermal structure of water, differentiating lakes from one another. The study was carried out on 141 lakes in northern Poland, for which at least 3 vertical water temperature measurements were taken in different years. They showed a significant influence of lake basin morphometry upon the thermal structure of water in lakes. In general, measurements of the vertical distribution of water temperature showed clear diversity, and depending on the depth also thermal layers (epi-, meta- and hypolimnion). The results of the analysis of 8 lake morphometric parameters and 10 thermal stratification parameters revealed the existence of significant dependencies between them. The best-preserved relations (statistically significant) occurred between the parameters characterizing the lake depth and meta- and hypolimnion properties, as well as the thermal stratification factor and heat content in a unit of volume.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"89 - 95"},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42380945","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. Zieliński, A. Choiński, S. Machula, A. Ławniczak, A. Strzelczak
Abstract The aim of this study was to reveal the chemical composition of bottom sediments in karst lakes located in the northern part of Połaniec Basin (eastern part of the Nida Basin, vicinity of Staszów municipality). A field investigation was carried out in 2010 on four lakes: Duży Staw, Donica, Dziki Staw and Łajba. The contents of a very wide range of chemical elements were determined, which is a rarity. On the basis of our research, it was found that the analysed lakes differed considerably between each other in spite of their close location. In general, sediments contained fair amounts of organic substances as well as Fe, Al, Ca and Mg due to the type of source rock and soligenic lake water supply. Increased concentrations of V, Cr and Ni might be explained by the weathering of rock material. In turn, higher contents of Zn, Pb, Cu and Co in the bottom sediments from Duży Staw indicated anthropopression. The measurement results obtained in this study will allow a future comparative analysis with bottom sediments from other lakes.
{"title":"Chemistry of Bottom Sediments from Selected Karst Lakes in the Vicinity of Staszów (Nida Basin)","authors":"A. Zieliński, A. Choiński, S. Machula, A. Ławniczak, A. Strzelczak","doi":"10.2478/limre-2020-0009","DOIUrl":"https://doi.org/10.2478/limre-2020-0009","url":null,"abstract":"Abstract The aim of this study was to reveal the chemical composition of bottom sediments in karst lakes located in the northern part of Połaniec Basin (eastern part of the Nida Basin, vicinity of Staszów municipality). A field investigation was carried out in 2010 on four lakes: Duży Staw, Donica, Dziki Staw and Łajba. The contents of a very wide range of chemical elements were determined, which is a rarity. On the basis of our research, it was found that the analysed lakes differed considerably between each other in spite of their close location. In general, sediments contained fair amounts of organic substances as well as Fe, Al, Ca and Mg due to the type of source rock and soligenic lake water supply. Increased concentrations of V, Cr and Ni might be explained by the weathering of rock material. In turn, higher contents of Zn, Pb, Cu and Co in the bottom sediments from Duży Staw indicated anthropopression. The measurement results obtained in this study will allow a future comparative analysis with bottom sediments from other lakes.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"81 - 87"},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44448261","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 creation of digital bathymetric models (DBM) of lakes allows not only for storage of the data on depths and shorelines in a standard format, but also for the estimation of the major morphometric characteristics of the reservoirs. To calculate the water, thermal, and chemical budgets of large lakes, it is important to know their hypsometry. We developed a new digital model of Lake Ladoga, the largest European lake, which was done to identify and correct topographic data errors, as well as to identify more depth points. The produced bathymetric model of the lake allowed for the updating of morphometric characteristics. The lake-bottom grid of 0.5×0.5 km with 70190 depth points of interest was produced using the kriging procedure with the mean error ME = 0.05 m and root mean square error RMSE = 5.6 m. The statistical characteristics of the lake depth and slope are determined on the basis of the advanced digital model of the lakebed relief. The form of the lake depression corresponds to the convex type (microtype) and bears some similarity to lakes Erie, Huron, Vanern, and Malaren. We describe how the bathymetric model has been developed and the morphometric characteristics of the lake have been corrected. We also discuss the results of its application in limnological investigations. A relationship has been established between surface water temperature, transparency and the bottom depths for the various seasons of Lake Ladoga.
{"title":"Lake Ladoga Digital Bathymetric Models: Development Approaches and Insight for Limnological Investigations","authors":"M. Naumenko","doi":"10.2478/limre-2020-0008","DOIUrl":"https://doi.org/10.2478/limre-2020-0008","url":null,"abstract":"Abstract The creation of digital bathymetric models (DBM) of lakes allows not only for storage of the data on depths and shorelines in a standard format, but also for the estimation of the major morphometric characteristics of the reservoirs. To calculate the water, thermal, and chemical budgets of large lakes, it is important to know their hypsometry. We developed a new digital model of Lake Ladoga, the largest European lake, which was done to identify and correct topographic data errors, as well as to identify more depth points. The produced bathymetric model of the lake allowed for the updating of morphometric characteristics. The lake-bottom grid of 0.5×0.5 km with 70190 depth points of interest was produced using the kriging procedure with the mean error ME = 0.05 m and root mean square error RMSE = 5.6 m. The statistical characteristics of the lake depth and slope are determined on the basis of the advanced digital model of the lakebed relief. The form of the lake depression corresponds to the convex type (microtype) and bears some similarity to lakes Erie, Huron, Vanern, and Malaren. We describe how the bathymetric model has been developed and the morphometric characteristics of the lake have been corrected. We also discuss the results of its application in limnological investigations. A relationship has been established between surface water temperature, transparency and the bottom depths for the various seasons of Lake Ladoga.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"65 - 80"},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44569171","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}
M. Ptak, A. Choiński, Aleksandra Pych, J. Piekarczyk
Abstract The paper presents the applicability of LiDAR data in limnological research with respect to the identification of the shoreline of lakes, and consequently the scale of overgrowing of lakes. Data obtained from the Head Office of Geodesy and Cartography from the period 2011 2016 provided the basis for the identification of shorelines for 14 lakes of the Pomeranian Lakeland. The paper employs the orthophotomap for the determination of the range of lake vegetation. Using the line determined based on the orthophotomap and that determined based on LiDAR points, the zone of overgrowing of the analysed lakes was delineated. In all the analysed cases combined, the water surface area was found to be reduced in comparison to the shoreline identified through LiDAR scanning by 161.5 ha, suggesting a 21.2% share of vegetation in the surface area of lakes.
{"title":"Applicability of Airborne Laser Scanning in the Identification of Lake Shorelines","authors":"M. Ptak, A. Choiński, Aleksandra Pych, J. Piekarczyk","doi":"10.2478/limre-2020-0006","DOIUrl":"https://doi.org/10.2478/limre-2020-0006","url":null,"abstract":"Abstract The paper presents the applicability of LiDAR data in limnological research with respect to the identification of the shoreline of lakes, and consequently the scale of overgrowing of lakes. Data obtained from the Head Office of Geodesy and Cartography from the period 2011 2016 provided the basis for the identification of shorelines for 14 lakes of the Pomeranian Lakeland. The paper employs the orthophotomap for the determination of the range of lake vegetation. Using the line determined based on the orthophotomap and that determined based on LiDAR points, the zone of overgrowing of the analysed lakes was delineated. In all the analysed cases combined, the water surface area was found to be reduced in comparison to the shoreline identified through LiDAR scanning by 161.5 ha, suggesting a 21.2% share of vegetation in the surface area of lakes.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"51 - 58"},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42860575","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. Volchak, I. Kirvel, A. Choiński, Sergey I. Parfomuk, P. Kirvel, S. Sidak
Abstract On the basis of the mean volume of annual water levels of 25 lakes (9 Belarusian and 16 Polish) over a period of 55 years (1956-2010) spectral time analysis of water fluctuations has been executed. The choice of the lakes was based on two factors, i.e. the continuous period of observation and insignificant anthropogenic influence. The complex analysis of water level fluctuation cycles has shown that for Belarus the cycles observed most often were 3, 5 and 10-year cycles. Polish lakes also have three cycles, but in the majority of them they amount to 5 and 10-years. It can be assumed that this is impacted by the continental climate growing to the east. Most probably it is one of the key factors defining the diversity of water fluctuations in all the analyzed lakes.
{"title":"Spectral–time analysis of cycle fluctuations in lake water levels in Belarus and Poland","authors":"A. Volchak, I. Kirvel, A. Choiński, Sergey I. Parfomuk, P. Kirvel, S. Sidak","doi":"10.2478/limre-2020-0001","DOIUrl":"https://doi.org/10.2478/limre-2020-0001","url":null,"abstract":"Abstract On the basis of the mean volume of annual water levels of 25 lakes (9 Belarusian and 16 Polish) over a period of 55 years (1956-2010) spectral time analysis of water fluctuations has been executed. The choice of the lakes was based on two factors, i.e. the continuous period of observation and insignificant anthropogenic influence. The complex analysis of water level fluctuation cycles has shown that for Belarus the cycles observed most often were 3, 5 and 10-year cycles. Polish lakes also have three cycles, but in the majority of them they amount to 5 and 10-years. It can be assumed that this is impacted by the continental climate growing to the east. Most probably it is one of the key factors defining the diversity of water fluctuations in all the analyzed lakes.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"11 - 3"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47990951","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}
M. Sajad, M. S. Khan, Saraj Bahadur, Muhammad Shuaib, A. Naeem, Wajid Zaman, H. Ali
Abstract Nickel is a known hepatotoxic, haemotoxic, pulmonary toxic, nephrotoxic, reproductive toxic, carcinogenic, phytotoxic and neurotoxic agent. The adverse ecological impacts from unnecessary heavy metals include contamination of water and soil which pose serious threats to human health. This study was conducted to screen plants for the phytoremediation of nickel from sixty-one sites of the Lower Dir. Nickel-metal was analyzed in the soil, roots and shoots of plants. The total concentration of nickel in soil, roots and shoots was found to be in the range of 1.03-18.98, 12.63-540.73 and 12.00-295.86 mg kg–1 dry weight basis (DW) respectively. The highest nickel contents were present in the roots of Xanthium strumarium (540.73) and shoots of Bryophyllum daigremontianum (295.86). None of the plant species were identified as hyper accumulators for nickel but based on BCF, TF and BAC values most of the species showed feasibility for its phytoextraction and phytostabilization. Xanthium strumarium, Filago hurdwarica, Ranunculus arvensis, Medicago lupulina, Cannabis sativa, Geranium rotundifolium and Cerastium glomeratum are suggested for the phytostabilization of nickel whereas Bryophyllum daigremontianum, Rosularia adenotricha, Iris germanica, Asplenium dalhousiae and Isatis tinctoria for the phytoextraction of soil contaminated with nickel.
{"title":"Nickel phytoremediation potential of some plant species of the Lower Dir, Khyber Pakhtunkhwa, Pakistan","authors":"M. Sajad, M. S. Khan, Saraj Bahadur, Muhammad Shuaib, A. Naeem, Wajid Zaman, H. Ali","doi":"10.2478/limre-2020-0002","DOIUrl":"https://doi.org/10.2478/limre-2020-0002","url":null,"abstract":"Abstract Nickel is a known hepatotoxic, haemotoxic, pulmonary toxic, nephrotoxic, reproductive toxic, carcinogenic, phytotoxic and neurotoxic agent. The adverse ecological impacts from unnecessary heavy metals include contamination of water and soil which pose serious threats to human health. This study was conducted to screen plants for the phytoremediation of nickel from sixty-one sites of the Lower Dir. Nickel-metal was analyzed in the soil, roots and shoots of plants. The total concentration of nickel in soil, roots and shoots was found to be in the range of 1.03-18.98, 12.63-540.73 and 12.00-295.86 mg kg–1 dry weight basis (DW) respectively. The highest nickel contents were present in the roots of Xanthium strumarium (540.73) and shoots of Bryophyllum daigremontianum (295.86). None of the plant species were identified as hyper accumulators for nickel but based on BCF, TF and BAC values most of the species showed feasibility for its phytoextraction and phytostabilization. Xanthium strumarium, Filago hurdwarica, Ranunculus arvensis, Medicago lupulina, Cannabis sativa, Geranium rotundifolium and Cerastium glomeratum are suggested for the phytostabilization of nickel whereas Bryophyllum daigremontianum, Rosularia adenotricha, Iris germanica, Asplenium dalhousiae and Isatis tinctoria for the phytoextraction of soil contaminated with nickel.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"13 - 22"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43530398","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 Marine ecosystems are vital natural resources that contribute to the global biogeochemical cycle, food, and energy production. In order to monitor and evaluate variations of different factors for decision making processes, validated ecosystem models were used in this study to analyze the evolution of different variables: temperature and salinity concentrations (from 1987 to 2014) and nitrate, phosphate, dissolved oxygen, chlorophyll concentrations, and phytoplankton biomass (from 1999 to 2014) in four sites (from 0 to 66 m depth) along the Levantine Sea: Lebanon, Turkey, Egypt and in the Open Sea. Principal component analysis and TRIX were then applied. Spatio-temporal analysis and PCA results showed that phytoplankton biomass is temporally affected by temperature and nutrients (in all stations) as well as salinity in some cases, in addition to its decrease with depth. TRIX analysis showed that all stations had higher primary productivity, in the first half of the year (January-May). Intense anthropogenic activities in Turkey and Egypt have altered the ecosystem’s stability and affected the phytoplankton biomass.
{"title":"On the use of validated ocean models to investigate the evolution of primary productivity in the Levantine Sea","authors":"Malak Kanj, A. Fadel","doi":"10.2478/limre-2020-0003","DOIUrl":"https://doi.org/10.2478/limre-2020-0003","url":null,"abstract":"Abstract Marine ecosystems are vital natural resources that contribute to the global biogeochemical cycle, food, and energy production. In order to monitor and evaluate variations of different factors for decision making processes, validated ecosystem models were used in this study to analyze the evolution of different variables: temperature and salinity concentrations (from 1987 to 2014) and nitrate, phosphate, dissolved oxygen, chlorophyll concentrations, and phytoplankton biomass (from 1999 to 2014) in four sites (from 0 to 66 m depth) along the Levantine Sea: Lebanon, Turkey, Egypt and in the Open Sea. Principal component analysis and TRIX were then applied. Spatio-temporal analysis and PCA results showed that phytoplankton biomass is temporally affected by temperature and nutrients (in all stations) as well as salinity in some cases, in addition to its decrease with depth. TRIX analysis showed that all stations had higher primary productivity, in the first half of the year (January-May). Intense anthropogenic activities in Turkey and Egypt have altered the ecosystem’s stability and affected the phytoplankton biomass.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"23 - 31"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48844094","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. Pasztaleniec, A. Hutorowicz, A. Napiórkowska-Krzebietke
Abstract The purpose of the study was to ascertain the effect of cyanobacterial abundance and its taxonomic structure on the results of measurements made by a fluorometric device designed to detect in situ chlorophyll a and phycocyanin. A multiparameter water quality probe was tested at 10 lakes located in the Wel River catchment. We found a strong correlation between the chlorophyll a concentration determined by laboratory procedure (CHL-a) and that obtained as a result of the probe measurements (YSI CHL-a) (R=0.78) as well as between the YSI CHL-a and the total phytoplankton biomass (R=0.73), whereas YSI CHL-a was not a good predictor of cyanobacterial biomass (R=0.24). The phycocyanin recorded by the probe was proportional to the total biomass of cyanobacteria (R=0.86); however, this cyanobacterial taxonomic structure influenced the fluorometric signal. Nevertheless, our study showed significant differentiation of phycocyanin measurement distribution at different levels of cyanobacterial abundance (<2 mg L−1, between 2 and 10 mg L−1, and >10 mg L−1), which indicates that the PC-YSI measurements are valuable in the detection of increased risk of exceeding health alert thresholds recommended by the WHO.
{"title":"Rapid monitoring of cyanobacteria in lakes – a case study in the Wel River catchment, Poland","authors":"A. Pasztaleniec, A. Hutorowicz, A. Napiórkowska-Krzebietke","doi":"10.2478/limre-2020-0005","DOIUrl":"https://doi.org/10.2478/limre-2020-0005","url":null,"abstract":"Abstract The purpose of the study was to ascertain the effect of cyanobacterial abundance and its taxonomic structure on the results of measurements made by a fluorometric device designed to detect in situ chlorophyll a and phycocyanin. A multiparameter water quality probe was tested at 10 lakes located in the Wel River catchment. We found a strong correlation between the chlorophyll a concentration determined by laboratory procedure (CHL-a) and that obtained as a result of the probe measurements (YSI CHL-a) (R=0.78) as well as between the YSI CHL-a and the total phytoplankton biomass (R=0.73), whereas YSI CHL-a was not a good predictor of cyanobacterial biomass (R=0.24). The phycocyanin recorded by the probe was proportional to the total biomass of cyanobacteria (R=0.86); however, this cyanobacterial taxonomic structure influenced the fluorometric signal. Nevertheless, our study showed significant differentiation of phycocyanin measurement distribution at different levels of cyanobacterial abundance (<2 mg L−1, between 2 and 10 mg L−1, and >10 mg L−1), which indicates that the PC-YSI measurements are valuable in the detection of increased risk of exceeding health alert thresholds recommended by the WHO.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"41 - 49"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46110098","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 the results of calculations and a verification of numerical models developed for estimating the surface of leaves of the common reed (Phragmites australis (Cav.) Trin. Ex Steud.). The research sample consisted of 137 leaves collected from the rush zone of Lake Raduńskie Górne in 2018. The total area of leaves obtained for testing was 1932.3 cm2. To derive a formula that returns the surface of common reed foliage regression models were used – MLR (Multiple Linear Regression) and SLR (Stepwise Linear Regression). It has been shown that the measurement of basic leaf dimensions (i.e. length – L, mid-width – WM and maximum width – WX) makes it possible to define an empirical formula which, with an average accuracy of 99.9%, allows the real surface of leaves to be estimated. The modelling results were compared with formulas currently used in practice, and the measurement errors were determined using these formulas. It has been shown that the formulas used to date are subject to RMSE to the value of 1.19-2.52. The application of the developed formula (A = 0.4486 – 0.046 L + 7.9267 WM – 5.8121 WX + 0.5853 L • WX) will significantly reduce errors in leaf surface estimation (RMSE = 0.86) and thus the amount of reed transpiration and evapotranspiration, especially in the case of handling small samples (number of leaves and measurements).
{"title":"The use of numerical methods in the design of a formula that returns the surface of the leaves of Phragmites australis (Cav.) Trin. Ex Steud.","authors":"K. Krzyżanowska, Paweł Krzyżanowski","doi":"10.2478/limre-2020-0004","DOIUrl":"https://doi.org/10.2478/limre-2020-0004","url":null,"abstract":"Abstract The paper presents the results of calculations and a verification of numerical models developed for estimating the surface of leaves of the common reed (Phragmites australis (Cav.) Trin. Ex Steud.). The research sample consisted of 137 leaves collected from the rush zone of Lake Raduńskie Górne in 2018. The total area of leaves obtained for testing was 1932.3 cm2. To derive a formula that returns the surface of common reed foliage regression models were used – MLR (Multiple Linear Regression) and SLR (Stepwise Linear Regression). It has been shown that the measurement of basic leaf dimensions (i.e. length – L, mid-width – WM and maximum width – WX) makes it possible to define an empirical formula which, with an average accuracy of 99.9%, allows the real surface of leaves to be estimated. The modelling results were compared with formulas currently used in practice, and the measurement errors were determined using these formulas. It has been shown that the formulas used to date are subject to RMSE to the value of 1.19-2.52. The application of the developed formula (A = 0.4486 – 0.046 L + 7.9267 WM – 5.8121 WX + 0.5853 L • WX) will significantly reduce errors in leaf surface estimation (RMSE = 0.86) and thus the amount of reed transpiration and evapotranspiration, especially in the case of handling small samples (number of leaves and measurements).","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"20 1","pages":"33 - 39"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45987285","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 In river-lake systems, reservoirs significantly affect the formation of water resources in the catchment by reducing the maximum flows and floods as well as increasing the low flows. In lake catchments, the pace of hydrological drought progression is usually slow. However, this phenomenon can be very extreme and destructive for water balance structure as a result of the very slow renewal rate of catchment resources. An estimation of hydrological drought development was conducted in the Biebrza river catchment (6,900 km2) on the basis of a daily discharge series for 18 water-gauge stations in the period 1982–2014. The number and location of the gauges allowed reliable results of the spatial pattern of drought to be obtained. The main objective of the research was the construction and assessment of the applicability of indicators which are estimators of drought spatial progression. Comparative analysis of four proposed indices led to two of them being recommended. These characteristics estimate the direction of drought development according to the stream network hierarchy, location of sub-catchments and the direction of river basin area increase. As a result, determinants of the spatial development of hydrological drought as well as its importance in the hydrographical structure were identified. Furthermore, the intensity of drought was evaluated and all investigated indices were applied to a time series analysis.
{"title":"Spatial development of hydrological droughts in lake catchments","authors":"M. Kozek, E. Tomaszewski","doi":"10.2478/limre-2019-0014","DOIUrl":"https://doi.org/10.2478/limre-2019-0014","url":null,"abstract":"Abstract In river-lake systems, reservoirs significantly affect the formation of water resources in the catchment by reducing the maximum flows and floods as well as increasing the low flows. In lake catchments, the pace of hydrological drought progression is usually slow. However, this phenomenon can be very extreme and destructive for water balance structure as a result of the very slow renewal rate of catchment resources. An estimation of hydrological drought development was conducted in the Biebrza river catchment (6,900 km2) on the basis of a daily discharge series for 18 water-gauge stations in the period 1982–2014. The number and location of the gauges allowed reliable results of the spatial pattern of drought to be obtained. The main objective of the research was the construction and assessment of the applicability of indicators which are estimators of drought spatial progression. Comparative analysis of four proposed indices led to two of them being recommended. These characteristics estimate the direction of drought development according to the stream network hierarchy, location of sub-catchments and the direction of river basin area increase. As a result, determinants of the spatial development of hydrological drought as well as its importance in the hydrographical structure were identified. Furthermore, the intensity of drought was evaluated and all investigated indices were applied to a time series analysis.","PeriodicalId":36922,"journal":{"name":"Limnological Review","volume":"19 1","pages":"159 - 174"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44345080","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}