Tamás Kucserka - Academia.edu (original) (raw)

Papers by Tamás Kucserka

Research paper thumbnail of Adsorption-Based Pretreatment of Irrigation Water to Prevent Water Quality Issues

Separations

Access to and the use of irrigation water of adequate quality and targeted nutrient supplementati... more Access to and the use of irrigation water of adequate quality and targeted nutrient supplementation have become more widespread in recent years. Both crop quality and the irrigation system lifetime are affected by the quality of the water used for irrigation. Micro-irrigation (e.g., drip and sprinkle) is becoming increasingly common alongside the more typical irrigation methods, but it requires expertise and pre-treatment to ensure a proper water supply. The most significant problem is clogging, which can greatly reduce irrigation efficiency. Treatment for irrigation purposes mainly depends on the contaminants that are present in the water. The main treatment options available are biological, electromagnetic and electrostatic treatments, but these have a wide range of effectiveness levels compared to membrane separation technologies. In addition, adsorption treatments are also available, which, depending on the adsorbent used, can greatly improve the pre-treatment of irrigation wate...

Research paper thumbnail of A kecskerák (Astacus leptodactylus) előfordulása a Balatonban

Because of Aphanomyces astaci and Anguilla anguilla settlements species like Astacus Leptodactylu... more Because of Aphanomyces astaci and Anguilla anguilla settlements species like Astacus Leptodactylus are forgotten but nowadays they are starting to spread again. Three native species of crabs are present in Hungary: Astacus astacus, Astacus leptodactylus and Astacus torrentium but you can also find Orconectes limosus. My purpose was to research Astacus leptodactylus which veryfied the multiplication of species in the coasts of Lake Balaton at Keszthely bay. We put out traps for a whole year with a total cought 209 crayfish, and one Spinnycheak Crayfish. During our research we measured the length of crayfishes’ bodies and scissors. We caught 9-10 cm long crabs in average, but the biggest was 18 cm long

Research paper thumbnail of Investigation of the leaching dynamics of the dominant macrophyte (Phragmites australis) in the area of Lake Balaton and Kis-Balaton Wetland System

Research paper thumbnail of Balaton湖地域,ハンガリーにおけるパン蒸発に及ぼす浸漬,淡水大型水生植物と沿岸堆積物の影響【Powered by NICT】

Journal of Hydrology, 2016

Research paper thumbnail of Decomposition dynamics of willow and poplar leaf litter in the area of Lake Balaton and Kis-Balaton Wetland System

Research paper thumbnail of A mikroszkopikus gombák szerepe az avar lebontásában hazai patakokban = The role of microscopic fungi in leaf litter decomposition in Hungarian streams

Research paper thumbnail of Decoupling shredder activity and physical abrasion in leaf litter decomposition process: experiments in the Torna-stream (Hungary) affected by red sludge spill

Hydrobiologia, 2016

Leaf litter represents a significant energy source for headwater ecosystems. Its breakdown includ... more Leaf litter represents a significant energy source for headwater ecosystems. Its breakdown includes dissolution, microbial activity, fragmentation by shredders, and physical abrasion. As a consequence of red sludge spill that took place in October 2010 in Hungary, the fauna of Torna-stream was killed, offering a “natural laboratory” to measure mass loss without shredder activity. Decomposition of nine leaf litter types was investigated with litter-bag method in 2011 (no macroinvertebrates; post-disaster experiment, POST), 2012 (after macroinvertebrate recolonization, at two sites: POSTRE: impacted site and POSTREF: reference site) in the Torna-stream. In the POST it was possible to measure leaf mass loss without shredder activity and to separate the leaf decomposition rates for each contributor of decomposition with a newly developed model. The model simulates the mass loss through three processes: physical abrasion and drifting, leaching and microbial mineralization, and macroinvertebrate consumption. In 2011, physical abrasion, microbial decomposition, and leaching accounted for 10–50% of initial mass loss, while in the POSTRE and in POSTREF for only 5–47%. The rate of litter decomposition driven by shredders in POST was between 5 and 44%, and in the POSTRE and POSTREF it accounted for 24–90%. The most apparent result of the experiments described in this paper is that the presence or absence of macroinvertebrates determines the decay characteristics and underlines the key role of macroinvertebrates in leaf litter decomposition.

Research paper thumbnail of Leaf litter decomposition in Torna stream before and after a red mud disaster

Acta Biologica Hungarica, 2014

Research paper thumbnail of Investigation of soybean leaf area influenced by water supply

Research paper thumbnail of Effect of submerged, freshwater aquatic macrophytes and littoral sediments on pan evaporation in the Lake Balaton region, Hungary

Journal of Hydrology, 2016

Abstract The evaporation ( E p ) of a US Class A pan ( C ) with submerged, freshwater aquatic mac... more Abstract The evaporation ( E p ) of a US Class A pan ( C ) with submerged, freshwater aquatic macrophytes ( Potamogeton perfoliatus , Myriophyllum spicatum and Najas marina ), hereafter macrophytes ( P s ) and a sediment-covered bottom ( S ) was measured in Hungary during 2014–2015 using reference E of Shuttleworth ( E o ) and Penman-Monteith crop reference evapotranspiration (crop ET o ). There were two main climatic controls affecting variation in E : direct (air and water temperature) and indirect (wind-mediated change affecting the penetration of sunlight; precipitation inflow, impacting plant emergence). Lower seasonal mean E p rates of 2.75 ± 0.89, 2.83 ± 0.91 and 3.06 ± 1.14 mm day −1 were observed in C , S and P s , respectively, during the wet 2014. In the 2015 season, higher overall daily mean E p rates for C , S and P s were 3.76 ± 1.3, 4.19 ± 1.34 and 4.65 ± 1.52 mm day −1 , respectively. A comparison of US Class A pan E p containing macrophytes/sediments with that of a standard US Class A pan showed that pan coefficients ( K ap and K as ) might allow for more accurate on-site lake E estimates. In 2014, seasonal mean K as and K ap were 1.04 ± 0.14 and 1.09 ± 0.18, respectively. Slightly higher K a values were observed during the warm and dry 2015 ( K as : 1.15 ± 0.22; K ap : 1.26 ± 0.23). A K a value greater than 1 indicates that the E p of a US Class A pan containing macrophytes and sediment is always higher than that of C . The calculated E o overestimated measured E p of P s during the course of this study. During the warm-dry growing season, crop ET o was closest to E p of P s . Empirical coefficients can be useful for estimating E of lakes with submerged macrophytes more precisely. The accuracy of the estimate of Keszthely Bay’s E improved by 9.85% when K a was determined on site.

Research paper thumbnail of The effect of stream bed morphology on shredder abundance and leaf-litter decomposition in Hungarian midland streams

The aim of this study was to examine the differences between natural and morphologically modified... more The aim of this study was to examine the differences between natural and morphologically modified stream bed sections in Hungarian midland streams by means of macroinvertebrate shredder abundance and leaf litter decomposition, and identify the key drivers of poor shredder fauna in modified water bodies. Eight sampling sites on three low order Hungarian watercourses were selected and studied between the springs of 2008 and 2009. Three types of leaf litter were collected and placed into leaf litter bags that were fixed to a metal wire net on the bottom of the river bed. Samples were taken in every four weeks. Leaf litter content and decomposition rate was determined and macroinvertebrates identified. Gammaridae dominated among shredders and their proportion did not differ significantly in bags. The shredders' counts and the leaf litter decay rates were different in the experimental streams. The sampling sites located in modified stream sections, with limited availability of food, exhibited lower shredder densities but higher decomposition rates (k>0.01 d-1) than those observed in sites of undisturbed bed morphology with rich allochtonous organic matter (k<0.0077 d-1). However, no significant differences were obtained in decay rates among the leaf species. Our results suggest that shoreline vegetation and bed morphology are two equally important factors in determining functional properties of streams; and leaf litter decomposition rate is not only a function of shredder density. Thus decomposition rate can be an important functional variable for ecological status assessment of the water.

Research paper thumbnail of Investigation of willow, poplar and mixed leaf litter decomposition in the area of Lake Balaton and Kis-Balaton Wetland

Research paper thumbnail of Zebra mussels (Dreissena polymorpha) invasion affects native unionids in Lake Balaton, Hungary

Research paper thumbnail of Hínár lebontási ütemének vizsgálata a Balaton területén

Research paper thumbnail of Analyzing long-term evapotranspiration of Lake Fenéki wetland ( Kis-Balaton , Hungary ) between 1970 and 2012

The aim of the study was to estimate long term evapotranspiration (ET) of Kis-Balaton wetland thr... more The aim of the study was to estimate long term evapotranspiration (ET) of Kis-Balaton wetland through the investigation of Lake Fenéki. Data set was processed using the West-transdanubian Water Inspectorate methodology. Potential evapotranspiration (PET) was calculated using Hungarian empirical models (Antal and Dunay), while Lake Fertő formula was applied evaluating the ET that includes the impacts of vegetation. Calculated PET values of the wider (adjacent) environment of Lake Fenéki (Zalaegerszeg, Nagykanizsa, and Keszthely meteorological stations) differed significantly and further variation was observed in PET, when measured meteorological elements on Lake Fenéki were applied. PET increment, as a result of linear trend fitted to the 43-year long data (Keszthely station) was 3–4 mm year. Relation between PET calculated from the data of Keszthely station and for Lake Fenéki was strong, so PET of Lake Fenéki can be originated from the data of Keszthely station. Calculated ET was n...

Research paper thumbnail of The Effect of Stream Bed Morphology on Shredder Abundance and Leaf-Litter Decomposition in Hungarian Midland Streams

The aim of this study was to examine the differences between natural and morphologically modified... more The aim of this study was to examine the differences between natural and morphologically modified stream bed sections in Hungarian midland streams by means of macroinvertebrate shredder abundance and leaf litter decomposition, and identify the key drivers of poor shredder fauna in modified water bodies. Eight sampling sites on three low order Hungarian watercourses were selected and studied between the springs of 2008 and 2009. Three types of leaf litter were collected and placed into leaf litter bags that were fixed to a metal wire net on the bottom of the river bed. Samples were taken in every four weeks. Leaf litter content and decomposition rate was determined and macroinvertebrates identified. Gammaridae dominated among shredders and their proportion did not differ significantly in bags. The shredders’ counts and the leaf litter decay rates were different in the experimental streams. The sampling sites located in modified stream sections, with limited availability of food, exhi...

Research paper thumbnail of Yield features of two soybean varieties under different water supplies and field conditions

Field Crops Research

Abstract The aim of the study was to quantify the impact of water stress, based on crop water str... more Abstract The aim of the study was to quantify the impact of water stress, based on crop water stress index on the yield and yield components in two soybean (Glycine max L.) varieties Sinara and Sigalia with distinct water demand. Three water levels were imposed during 2017 and 2018 growing seasons: 1) the unlimited in traditional evapotranspirometers, 2) the halved evapotranspiration during flowering and 3) the rainfed. LAI was recorded at weekly intervals. Total aboveground biomass, seed yield, 1000-grain weight, oil and protein contents were measured at harvest. Irrespective of water supply, the water stress tolerant Sinara had greater seed yield due to increased LAI, dry matter and 1000-grain weight compared to Sigalia that may be advantageous to obtain stable yield under variable weather conditions. The relationship between water stress index and seed yield (R2 = 0.744) was best described by polynomial function; as the evapotranspiration increased, the water stress index in line with crop temperatures, Tc and its SD values decreased. Linear relationship between water stress index and water use efficiency exhibited that each 0.1 increase in water stress index above 0.2 would improve the soybean water use efficiency by 0.49 ± 0.13 kg m−3. This information could particularly be useful for farmers cultivating the soybean on water scarce areas.

Research paper thumbnail of Some preliminary investigations of water quality parameters in a Hungarian thermal lake, Hévíz

Journal of Central European Agriculture

Recently, there were only a few investigations published related to thermal waters in all over th... more Recently, there were only a few investigations published related to thermal waters in all over the world. In this study, an assessment on lake water quality was carried out in Lake Hévíz and its effluent, to provide valuable information about the present lake water quality in the winter season. In Hévíz, the thermal lake has an economic, geological and medical significance, and plays an important role in the tourism industry. Monitoring the quality of water resources-where thermal waters are present-is of primary importance. The chemical composition of geothermal waters often differs markedly from surface waters. The direct drainage of used geothermal waters getting into freshwaters is usually not authorized, so the excess thermal water of Lake Hévíz dilutes in the outflow effluent. A principal component analysis (PCA) was applied to explore the surface water quality dataset. Three sampling points were chosen from the effluent characterized by different water temperatures. The study took place between 9 th December, 2019 and 16th March, 2020. There were 9 sampling times to measure conductivity, pH, biological and chemical oxygen demand, total organic carbon, ammonium-, phosphate-, sulphate concentration at the same sampling time. The highest water quality values were determined in the third sampling point of the outflow effluent, where the water temperature was the lowest. Temperature is an important factor in the aquatic environment since it affects directly or indirectly the aquatic flora and fauna. This study is important in providing comprehensive information on water quality for decision makers in particular the thermal waters and valuable reference for international researchers.

Research paper thumbnail of Estimation of natural water body’s evaporation based on Class A pan measurements in comparison to reference evapotranspiration

Időjárás

in the growing season of 2016. Some of the evaporation pans were implemented with freshwater aqua... more in the growing season of 2016. Some of the evaporation pans were implemented with freshwater aquatic macrophytes (Myriophyllum sp., Potamogeton sp., and Najas sp.) (P s) and sediment covered bottom (S). The applied macrophytes were the predominant species of Keszthely Bay (Balaton Lake). Reference (E o) after Shuttleworth and reference evapotranspiration (ET o) after Penman-Monteith (FAO-56 formula) were also included for the E study. Of pre-selected four investigated variables, air temperature and air humidity impacted E p of treated Class A pans the most. Cumulative E p values for 2016 were 363.1, 427.7, and 461.5 mm in C, S, and Ps, respectively. There was no difference in measured cumulative E p of P s (461.5 mm) and computed ET o (472.1 mm) during the studied season. On the basis of a simplified water budget, E rate of Keszthely Bay increased with 16.9%, when macrophytes and sediment cover were accounted. It is equivalent to 264,000,000 m 3 water in Keszthely Bay's E estimation. Simple E approach-when lake's components, such as submerged macrophytes and sediment cover were also accounted-could extend the accuracy of natural lake's E estimation in a broader circle than earlier.

Research paper thumbnail of Investigation of the decomposition and leaching dynamics of Salix, Populus and mixed leaves in the area of Lake Balaton and Kis-Balaton Wetland

Acta Agraria Debreceniensis

In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient ... more In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient load and plays a basic structural and functional role in several ecosystems. In Hungary, at the banks of lakes and wetlands, Salix and Populus trees are the most common species. In an experiment in Lake Balaton and Kis-Balaton Wetland between 16 November 2017 to and 3 June 2018, the decomposition rates and leaching dynamics of Salix, Populus and mixed leaves (50% Salix and 50% Populus) were investigated. Total nitrogen and phosphorus content of biomass samples were measured at the beginning and end of the experiment for the leaching dynamics experiment. We found that litter mass losses (Salix, Populus and mixed leaves) were not significantly different between the two mesh size litterbags and between Lake Balaton and Kis-Balaton Wetland. Different amounts of the total nitrogen and phosphorus leaching from Salix, Populus and mixed leaves were detected. The total nitrogen contents of the pl...

Research paper thumbnail of Adsorption-Based Pretreatment of Irrigation Water to Prevent Water Quality Issues

Separations

Access to and the use of irrigation water of adequate quality and targeted nutrient supplementati... more Access to and the use of irrigation water of adequate quality and targeted nutrient supplementation have become more widespread in recent years. Both crop quality and the irrigation system lifetime are affected by the quality of the water used for irrigation. Micro-irrigation (e.g., drip and sprinkle) is becoming increasingly common alongside the more typical irrigation methods, but it requires expertise and pre-treatment to ensure a proper water supply. The most significant problem is clogging, which can greatly reduce irrigation efficiency. Treatment for irrigation purposes mainly depends on the contaminants that are present in the water. The main treatment options available are biological, electromagnetic and electrostatic treatments, but these have a wide range of effectiveness levels compared to membrane separation technologies. In addition, adsorption treatments are also available, which, depending on the adsorbent used, can greatly improve the pre-treatment of irrigation wate...

Research paper thumbnail of A kecskerák (Astacus leptodactylus) előfordulása a Balatonban

Because of Aphanomyces astaci and Anguilla anguilla settlements species like Astacus Leptodactylu... more Because of Aphanomyces astaci and Anguilla anguilla settlements species like Astacus Leptodactylus are forgotten but nowadays they are starting to spread again. Three native species of crabs are present in Hungary: Astacus astacus, Astacus leptodactylus and Astacus torrentium but you can also find Orconectes limosus. My purpose was to research Astacus leptodactylus which veryfied the multiplication of species in the coasts of Lake Balaton at Keszthely bay. We put out traps for a whole year with a total cought 209 crayfish, and one Spinnycheak Crayfish. During our research we measured the length of crayfishes’ bodies and scissors. We caught 9-10 cm long crabs in average, but the biggest was 18 cm long

Research paper thumbnail of Investigation of the leaching dynamics of the dominant macrophyte (Phragmites australis) in the area of Lake Balaton and Kis-Balaton Wetland System

Research paper thumbnail of Balaton湖地域,ハンガリーにおけるパン蒸発に及ぼす浸漬,淡水大型水生植物と沿岸堆積物の影響【Powered by NICT】

Journal of Hydrology, 2016

Research paper thumbnail of Decomposition dynamics of willow and poplar leaf litter in the area of Lake Balaton and Kis-Balaton Wetland System

Research paper thumbnail of A mikroszkopikus gombák szerepe az avar lebontásában hazai patakokban = The role of microscopic fungi in leaf litter decomposition in Hungarian streams

Research paper thumbnail of Decoupling shredder activity and physical abrasion in leaf litter decomposition process: experiments in the Torna-stream (Hungary) affected by red sludge spill

Hydrobiologia, 2016

Leaf litter represents a significant energy source for headwater ecosystems. Its breakdown includ... more Leaf litter represents a significant energy source for headwater ecosystems. Its breakdown includes dissolution, microbial activity, fragmentation by shredders, and physical abrasion. As a consequence of red sludge spill that took place in October 2010 in Hungary, the fauna of Torna-stream was killed, offering a “natural laboratory” to measure mass loss without shredder activity. Decomposition of nine leaf litter types was investigated with litter-bag method in 2011 (no macroinvertebrates; post-disaster experiment, POST), 2012 (after macroinvertebrate recolonization, at two sites: POSTRE: impacted site and POSTREF: reference site) in the Torna-stream. In the POST it was possible to measure leaf mass loss without shredder activity and to separate the leaf decomposition rates for each contributor of decomposition with a newly developed model. The model simulates the mass loss through three processes: physical abrasion and drifting, leaching and microbial mineralization, and macroinvertebrate consumption. In 2011, physical abrasion, microbial decomposition, and leaching accounted for 10–50% of initial mass loss, while in the POSTRE and in POSTREF for only 5–47%. The rate of litter decomposition driven by shredders in POST was between 5 and 44%, and in the POSTRE and POSTREF it accounted for 24–90%. The most apparent result of the experiments described in this paper is that the presence or absence of macroinvertebrates determines the decay characteristics and underlines the key role of macroinvertebrates in leaf litter decomposition.

Research paper thumbnail of Leaf litter decomposition in Torna stream before and after a red mud disaster

Acta Biologica Hungarica, 2014

Research paper thumbnail of Investigation of soybean leaf area influenced by water supply

Research paper thumbnail of Effect of submerged, freshwater aquatic macrophytes and littoral sediments on pan evaporation in the Lake Balaton region, Hungary

Journal of Hydrology, 2016

Abstract The evaporation ( E p ) of a US Class A pan ( C ) with submerged, freshwater aquatic mac... more Abstract The evaporation ( E p ) of a US Class A pan ( C ) with submerged, freshwater aquatic macrophytes ( Potamogeton perfoliatus , Myriophyllum spicatum and Najas marina ), hereafter macrophytes ( P s ) and a sediment-covered bottom ( S ) was measured in Hungary during 2014–2015 using reference E of Shuttleworth ( E o ) and Penman-Monteith crop reference evapotranspiration (crop ET o ). There were two main climatic controls affecting variation in E : direct (air and water temperature) and indirect (wind-mediated change affecting the penetration of sunlight; precipitation inflow, impacting plant emergence). Lower seasonal mean E p rates of 2.75 ± 0.89, 2.83 ± 0.91 and 3.06 ± 1.14 mm day −1 were observed in C , S and P s , respectively, during the wet 2014. In the 2015 season, higher overall daily mean E p rates for C , S and P s were 3.76 ± 1.3, 4.19 ± 1.34 and 4.65 ± 1.52 mm day −1 , respectively. A comparison of US Class A pan E p containing macrophytes/sediments with that of a standard US Class A pan showed that pan coefficients ( K ap and K as ) might allow for more accurate on-site lake E estimates. In 2014, seasonal mean K as and K ap were 1.04 ± 0.14 and 1.09 ± 0.18, respectively. Slightly higher K a values were observed during the warm and dry 2015 ( K as : 1.15 ± 0.22; K ap : 1.26 ± 0.23). A K a value greater than 1 indicates that the E p of a US Class A pan containing macrophytes and sediment is always higher than that of C . The calculated E o overestimated measured E p of P s during the course of this study. During the warm-dry growing season, crop ET o was closest to E p of P s . Empirical coefficients can be useful for estimating E of lakes with submerged macrophytes more precisely. The accuracy of the estimate of Keszthely Bay’s E improved by 9.85% when K a was determined on site.

Research paper thumbnail of The effect of stream bed morphology on shredder abundance and leaf-litter decomposition in Hungarian midland streams

The aim of this study was to examine the differences between natural and morphologically modified... more The aim of this study was to examine the differences between natural and morphologically modified stream bed sections in Hungarian midland streams by means of macroinvertebrate shredder abundance and leaf litter decomposition, and identify the key drivers of poor shredder fauna in modified water bodies. Eight sampling sites on three low order Hungarian watercourses were selected and studied between the springs of 2008 and 2009. Three types of leaf litter were collected and placed into leaf litter bags that were fixed to a metal wire net on the bottom of the river bed. Samples were taken in every four weeks. Leaf litter content and decomposition rate was determined and macroinvertebrates identified. Gammaridae dominated among shredders and their proportion did not differ significantly in bags. The shredders' counts and the leaf litter decay rates were different in the experimental streams. The sampling sites located in modified stream sections, with limited availability of food, exhibited lower shredder densities but higher decomposition rates (k>0.01 d-1) than those observed in sites of undisturbed bed morphology with rich allochtonous organic matter (k<0.0077 d-1). However, no significant differences were obtained in decay rates among the leaf species. Our results suggest that shoreline vegetation and bed morphology are two equally important factors in determining functional properties of streams; and leaf litter decomposition rate is not only a function of shredder density. Thus decomposition rate can be an important functional variable for ecological status assessment of the water.

Research paper thumbnail of Investigation of willow, poplar and mixed leaf litter decomposition in the area of Lake Balaton and Kis-Balaton Wetland

Research paper thumbnail of Zebra mussels (Dreissena polymorpha) invasion affects native unionids in Lake Balaton, Hungary

Research paper thumbnail of Hínár lebontási ütemének vizsgálata a Balaton területén

Research paper thumbnail of Analyzing long-term evapotranspiration of Lake Fenéki wetland ( Kis-Balaton , Hungary ) between 1970 and 2012

The aim of the study was to estimate long term evapotranspiration (ET) of Kis-Balaton wetland thr... more The aim of the study was to estimate long term evapotranspiration (ET) of Kis-Balaton wetland through the investigation of Lake Fenéki. Data set was processed using the West-transdanubian Water Inspectorate methodology. Potential evapotranspiration (PET) was calculated using Hungarian empirical models (Antal and Dunay), while Lake Fertő formula was applied evaluating the ET that includes the impacts of vegetation. Calculated PET values of the wider (adjacent) environment of Lake Fenéki (Zalaegerszeg, Nagykanizsa, and Keszthely meteorological stations) differed significantly and further variation was observed in PET, when measured meteorological elements on Lake Fenéki were applied. PET increment, as a result of linear trend fitted to the 43-year long data (Keszthely station) was 3–4 mm year. Relation between PET calculated from the data of Keszthely station and for Lake Fenéki was strong, so PET of Lake Fenéki can be originated from the data of Keszthely station. Calculated ET was n...

Research paper thumbnail of The Effect of Stream Bed Morphology on Shredder Abundance and Leaf-Litter Decomposition in Hungarian Midland Streams

The aim of this study was to examine the differences between natural and morphologically modified... more The aim of this study was to examine the differences between natural and morphologically modified stream bed sections in Hungarian midland streams by means of macroinvertebrate shredder abundance and leaf litter decomposition, and identify the key drivers of poor shredder fauna in modified water bodies. Eight sampling sites on three low order Hungarian watercourses were selected and studied between the springs of 2008 and 2009. Three types of leaf litter were collected and placed into leaf litter bags that were fixed to a metal wire net on the bottom of the river bed. Samples were taken in every four weeks. Leaf litter content and decomposition rate was determined and macroinvertebrates identified. Gammaridae dominated among shredders and their proportion did not differ significantly in bags. The shredders’ counts and the leaf litter decay rates were different in the experimental streams. The sampling sites located in modified stream sections, with limited availability of food, exhi...

Research paper thumbnail of Yield features of two soybean varieties under different water supplies and field conditions

Field Crops Research

Abstract The aim of the study was to quantify the impact of water stress, based on crop water str... more Abstract The aim of the study was to quantify the impact of water stress, based on crop water stress index on the yield and yield components in two soybean (Glycine max L.) varieties Sinara and Sigalia with distinct water demand. Three water levels were imposed during 2017 and 2018 growing seasons: 1) the unlimited in traditional evapotranspirometers, 2) the halved evapotranspiration during flowering and 3) the rainfed. LAI was recorded at weekly intervals. Total aboveground biomass, seed yield, 1000-grain weight, oil and protein contents were measured at harvest. Irrespective of water supply, the water stress tolerant Sinara had greater seed yield due to increased LAI, dry matter and 1000-grain weight compared to Sigalia that may be advantageous to obtain stable yield under variable weather conditions. The relationship between water stress index and seed yield (R2 = 0.744) was best described by polynomial function; as the evapotranspiration increased, the water stress index in line with crop temperatures, Tc and its SD values decreased. Linear relationship between water stress index and water use efficiency exhibited that each 0.1 increase in water stress index above 0.2 would improve the soybean water use efficiency by 0.49 ± 0.13 kg m−3. This information could particularly be useful for farmers cultivating the soybean on water scarce areas.

Research paper thumbnail of Some preliminary investigations of water quality parameters in a Hungarian thermal lake, Hévíz

Journal of Central European Agriculture

Recently, there were only a few investigations published related to thermal waters in all over th... more Recently, there were only a few investigations published related to thermal waters in all over the world. In this study, an assessment on lake water quality was carried out in Lake Hévíz and its effluent, to provide valuable information about the present lake water quality in the winter season. In Hévíz, the thermal lake has an economic, geological and medical significance, and plays an important role in the tourism industry. Monitoring the quality of water resources-where thermal waters are present-is of primary importance. The chemical composition of geothermal waters often differs markedly from surface waters. The direct drainage of used geothermal waters getting into freshwaters is usually not authorized, so the excess thermal water of Lake Hévíz dilutes in the outflow effluent. A principal component analysis (PCA) was applied to explore the surface water quality dataset. Three sampling points were chosen from the effluent characterized by different water temperatures. The study took place between 9 th December, 2019 and 16th March, 2020. There were 9 sampling times to measure conductivity, pH, biological and chemical oxygen demand, total organic carbon, ammonium-, phosphate-, sulphate concentration at the same sampling time. The highest water quality values were determined in the third sampling point of the outflow effluent, where the water temperature was the lowest. Temperature is an important factor in the aquatic environment since it affects directly or indirectly the aquatic flora and fauna. This study is important in providing comprehensive information on water quality for decision makers in particular the thermal waters and valuable reference for international researchers.

Research paper thumbnail of Estimation of natural water body’s evaporation based on Class A pan measurements in comparison to reference evapotranspiration

Időjárás

in the growing season of 2016. Some of the evaporation pans were implemented with freshwater aqua... more in the growing season of 2016. Some of the evaporation pans were implemented with freshwater aquatic macrophytes (Myriophyllum sp., Potamogeton sp., and Najas sp.) (P s) and sediment covered bottom (S). The applied macrophytes were the predominant species of Keszthely Bay (Balaton Lake). Reference (E o) after Shuttleworth and reference evapotranspiration (ET o) after Penman-Monteith (FAO-56 formula) were also included for the E study. Of pre-selected four investigated variables, air temperature and air humidity impacted E p of treated Class A pans the most. Cumulative E p values for 2016 were 363.1, 427.7, and 461.5 mm in C, S, and Ps, respectively. There was no difference in measured cumulative E p of P s (461.5 mm) and computed ET o (472.1 mm) during the studied season. On the basis of a simplified water budget, E rate of Keszthely Bay increased with 16.9%, when macrophytes and sediment cover were accounted. It is equivalent to 264,000,000 m 3 water in Keszthely Bay's E estimation. Simple E approach-when lake's components, such as submerged macrophytes and sediment cover were also accounted-could extend the accuracy of natural lake's E estimation in a broader circle than earlier.

Research paper thumbnail of Investigation of the decomposition and leaching dynamics of Salix, Populus and mixed leaves in the area of Lake Balaton and Kis-Balaton Wetland

Acta Agraria Debreceniensis

In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient ... more In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient load and plays a basic structural and functional role in several ecosystems. In Hungary, at the banks of lakes and wetlands, Salix and Populus trees are the most common species. In an experiment in Lake Balaton and Kis-Balaton Wetland between 16 November 2017 to and 3 June 2018, the decomposition rates and leaching dynamics of Salix, Populus and mixed leaves (50% Salix and 50% Populus) were investigated. Total nitrogen and phosphorus content of biomass samples were measured at the beginning and end of the experiment for the leaching dynamics experiment. We found that litter mass losses (Salix, Populus and mixed leaves) were not significantly different between the two mesh size litterbags and between Lake Balaton and Kis-Balaton Wetland. Different amounts of the total nitrogen and phosphorus leaching from Salix, Populus and mixed leaves were detected. The total nitrogen contents of the pl...