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1

Distributions of Rhizostoma pulmo (Macri, 1778) between the Kızılırmak and the Yeşilırmak coast of the Black Sea, Türkiye

Dönmez Memet Ali, Bat Levent

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 3

273--286

EN

This study examined the seasonal distributions of the medusa Rhizostoma pulmo along the coasts of the southern Black Sea between Kızılırmak and Yeşilırmak between April 2008 and March 2010. Monthly abundance and biomass values were determined, as well as population parameters.The effect of temperature on medusa distribution wasalso investigated. Results showed that medusa abundance and biomass were highest in autumn, following a period of increased temperature. In contrast, medusa was not observed during the spring season. It was possible to observe the R. pulmo individuals for five months for the first term of investigation period (2008-2009), and seven months for the second term (2009-2010). The highest abundance value was found to be 10 n/m 2 (November 2008 and September 2009) and the highest biomass value was 12.587,5 g/100 m3 (October 2009).

2

The challenges of aquaculture in protecting the aquatic ecosystems in the context of climate changes

Wróbel Jacek, Gałczyńska Małgorzata, Tański Adam, Korzelecka-Orkisz Agata, Formicki Krzysztof

Journal of Water and Land Development

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2023

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no. 57

231--241

EN

The paper discusses the current prognoses of aquaculture development worldwide putting an emphasis on its effect on the environment and the issue of the protection of water reservoirs in different countries. Water consumption in diversified aquaculture systems is presented herein as well as the characteristics of the mechanical and biological water treatment methods in fish farms, with particular attention paid to the recirculating water systems. New aquaculture technologies using post-production waters are presented. The paper provides a discussion on the contribution of aquaculture to the global greenhouse gas emissions and the means of limiting this emission. The effect of climate change on aquatic ecosystems is presented in the context of the changes of the aquaculture production profile. The paper includes a brief presentation of the methods of mitigating the changes with respect to contamination of aquatic ecosystems as well as climate change. Reducing the water footprint can be achieved through selective breeding, species diversification and implementation of more technologically advanced aquaculture systems such as: integrated multi-trophic aquaculture, aquaponics and recirculation systems in aquaculture. The need for certification of fish farms with water recirculation systems is justified in the paper. The issues addressed herein are summarised and the main areas for extending the research promoting preservation of aquatic ecosystems in aquaculture are presented.

3

Internet of things for enhancement the quality of community: case study of aquatic nursery in Songkhla Lake Basin

Boonsong Wasana

Przegląd Elektrotechniczny

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2021

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R. 97, nr 3

138--140

EN

The Internet for all things is commonly known as (IoT). This system allows users to achieve more in-depth automation, analysis, and embedment within a system. This paper proposes IoT-water monitoring system (WMS) for enhancing the quality of water for the fishing community aquatic nursery at Songkhla Lake Basin. The objectives of this work are 1) to study the embedded IoT-system used for water monitoring in an aquatic animal pond and to explore the relationship between water temperature and dissolved oxygen (DO) values. Both parameters, water temperature and DO are tracked to observe and analyze their relationship within a period time. The analyzed results using Pearson’s correlation statistic found that the water temperature and dissolved oxygen values are negatively related. Namely, whenever the water temperature is high, the DO decreases accordingly and vice versa.

PL

W artykule zaproponowano wykorzystanie Internetu Rzeczy IoT do monitorowania wody w Songkhla Lake Basin w Tajlandii. Monitorowano zależność między temperaturą wody i rozpuszczonym w niej tlenem DO. Znaleziono negatywna korelację, tzn im wyższa temperatura wody tym mniej tlenu.

4

Establishment and range expansion of non-native fish species facilitated by hot springs: the case study from the Upper Sakarya Basin (NW, Turkey)

Aksu Sadi, Başkurt Sercan, Emiroğlu Özgür, Tarkan Ali Serhan

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 3

247--258

EN

Non-native species can enter new habitats and ecosystems in a variety of ways. Suitable ecological conditions must exist for non-native species to reproduce in newly colonized habitats. Hot springs are suitable habitats for tropical, aquarium, and ornamental fish species. This paper presents the results of research on the distribution of non-native and native species in relation to environmental factors in the Upper Sakarya Basin, where several such springs are present. The fish fauna in the basin includes native (60% – 21 species, 14 of which are endemic) and non-native (40% – 14 species) fish species. Most of the non-native species (seven species) were found only in warm springs (minimum water temperature 16°C). In addition, 75 fish species belonging to 26 families were found throughout the Sakarya Basin. Hot springs were found to play an important role in the establishment of non-native species. The Kernel Density Estimation (KDE) results revealed that the non-native species density was high in the Upper Sakarya Basin where hot springs are common. This confirms that minimum and maximum temperatures are the main drivers of changes in the distribution of non-native fish species. Two aquarium fishes, Bujurguina vittata and Xiphophorus spp., are reported for the first time in the present study for inland waters of Turkey.

5

Winter upwelling in the Gulf of Finland, Baltic Sea

Suursaar Ülo

Oceanologia

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2021

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No. 63 (3)

356--369

EN

Traditionally, upwelling-related studies in the Baltic Sea have been limited to the period from May to September. Based on wintertime in situ measurements at two nearshore locations in the Gulf of Finland, clear evidence of winter “warm” upwelling events was detected and analysed. The process was very common. At a 10 m deep location, upwelling caused water temperature (T) to switch from 0-1 to 4-5°C and salinity (S) to switch from 4.5 to 6 PSU; at 20 m depth it caused a switch in T between 1 and 2-4°C and in S between 5.5 and 6.8 PSU. Differently from summer upwelling, T and S variations were positively correlated to each other. Salinity variations remained roughly the same throughout the winter, whereas T differences were higher in winter onset, then decreased to ca. 1°C, and increased again after the process reversed to summer-type upwelling in April-May. Based on analysis of SatBaltyk (January to March) sea surface temperature and salinity product imagery, winter upwelling occurrence along the North Estonian coast was 21-28% over 2010-2021, and slightly less along the Finnish coast. Regarding S variations, winter upwelling occurred with roughly similar frequencies and impacts in the northern and southern parts of the gulf. However, the impacts on T and sea ice conditions were highly asymmetrical. Upwelling kept the Estonian coast ice-free longer and water temperatures slightly higher than at the Finnish coast. Winter upwelling as a phenomenon has long been ignored and therefore probably underestimated.

6

Development of an adaptive neuro-fuzzy inference system (ANFIS) model to predict sea surface temperature (SST)

Kale Semih

Oceanological and Hydrobiological Studies

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2020

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Vol. 49, No. 4

354--373

EN

An accurate estimation of the sea surface temperature (SST) is of great importance. Therefore, the objective of this work was to develop an adaptive neuro-fuzzy inference system (ANFIS) model to predict SST in the Çanakkale Strait. The observed monthly air temperature, evaporation and precipitation data from the Çanakkale meteorological observation station were used as input data. The Takagi–Sugeno fuzzy inference system was applied. The grid partition method (ANFIS-GP) and the subtractive clustering partitioning method (ANFIS-SC) were used with Gaussian membership functions to generate the fuzzy inference system. Six performance evaluation criteria were used to evaluate the developed SST prediction models, including mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), Nash-Sutcliffe efficiency (NSE) and correlation of determination (R2). The dataset was randomly divided into training and testing datasets for the machine learning process. Training data accounted for 75% of the dataset, while 25% of the dataset was allocated for testing in ANFIS. The hybrid algorithm was selected as a training algorithm for the ANFIS. Simulation results revealed that the ANFIS-SC4 model provided a higher correlation coefficient of 0.96 between the observed and predicted SST values. The results of this study suggest that the developed ANFIS model can be applied for predicting sea surface temperature around the world.

7

Combined impact of summer heat waves and coastal upwelling in the Baltic Sea

Suursaar Ülo

Oceanologia

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2020

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No. 62 (4PA)

511--524

EN

Under warming climates, heat waves (HWs) have occurred in increasing intensity in Europe. Also, public interest towards HWs has considerably increased over the last decades. The paper discusses the manifestations of the summer 2014 HW and simultaneously occurring coastal upwelling (CU) events in the Gulf of Finland. Caused by an anticyclonic weather pattern and persisting easterly winds, CUs evolved along the southern coast of the Gulf in four episodes from June to August. Based on data from coastal weather stations, 115 days-long measurements with a Recording Doppler Current Profiler (RDCP) oceanographic complex and sea surface temperature (SST) satellite images, the partly opposing impacts of these events are analysed. Occurring on the background of a marine HW (up to 26°C), the CU-forced SST variations reached about 20 degrees. At the 10 m deep RDCP mooring location, a drop from 21.5 to 2.9°C occurred within 60 hours. Salinity varied between 3.6 and 6.2 and an along-shore coastal jet was observed; the statistically preferred westerly current frequently flowed against the wind. Locally, the cooling effect of the CUs occasionally mitigated the overheating effects by the HWs both in the sea and on the marine-land boundary. However, in the elongated channel-like Gulf of Finland, upwelling at one coast is usually paired with downwelling at the opposite coast, and simultaneously or subsequently occurring HWs and CUs effectively contribute to heat transfer from the atmosphere to the water mass. Rising extremes of HWs and rapid variations by CUs may put the ecosystems under increasing stress.

8

Temperature and ice regimes of waterbodies under the impacts of global warming and a hydropower plant

Vyshnevskyi Viktor Ivanovych

Meteorology Hydrology and Water Management. Research and Operational Applications

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2020

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Vol. 8, Iss. 2

38--45

EN

Based on the results of regular monitoring and remote sensing data the patterns of water temperature and ice regime of the Dnipro River within Kyiv, as affected by global warming and a hydropower plant, were identified. The characteristic features of this stretch of the river are increasing water temperature, and the decreasing thickness and duration of ice cover. The largest water temperature increase is in summer, with a somewhat smaller increase in autumn. The increase of water temperature in spring is much less than the increase in air temperature. In summer, the gradient of water temperature increase is a little bit less than that of air temperature. In autumn, the gradient of water temperature increase is larger than the gradient of air temperature increase. From April to August the lowest water temperature is usually observed near the Kyivska hydropower plant (HPP), which is located upstream. During this period the water temperature downstream from HPP increases. The uneven daily operation of HPP causes the alternation of areas with different temperature along the Dnipro River. In the cold season the water temperature in the Dnipro River is usually higher than in other nearby urban water bodies. Freezing of the water area usually starts from the small and shallow lakes and ponds. The main branch of the Dnipro River freezes last. On the whole, the sequence of ice melting on the waterbodies is the reverse of the freezing process. The longest ice cover duration in spring is observed in the bays with small water exchange, mainly located at a large distance from Kyivska HPP.

9

Influence of a lake on river water thermal regime: A case study of Lake Sławianowskie and the Kocunia River (Pomeranian Lakeland, Northern Poland)

Nowak Bogumił, Ptak Mariusz, Stanek Paulina

Meteorology Hydrology and Water Management. Research and Operational Applications

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2020

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Vol. 8, Iss. 1

78--83

EN

Water temperature is one of the basic physical parameters of rivers and lakes. Rising temperature can transform these ecosystems over a broad range of factors (water mixing, water quality, biological conditions, etc.). In the case of rivers, their thermal regimes also can be modified by local conditions (e.g., tree cover, adjoining water bodies, etc.). In this paper, we address the functioning of the river-lake system in northern Poland (Kocunia River-Lake Sławianowskie) in terms of the effect of the lake on temperature conditions in the river. Dependencies in daily water temperatures between stations located above and below the lake were assessed with linear regression. Based on daily morning water temperatures for the period 2012-2017, it was determined that water temperature in the river below the lake was higher than at the measurement site located above the lake by an average of 1.1°C. The greatest differences were recorded in summerautumn months when average monthly downstream water temperatures were as much as 3.9°C higher than upstream water temperatures. This phenomenon is an example of a local factor (the lake) magnifying global factors, i.e. rising temperatures associated with climate change. The information in this paper can provide future reference for decision makers and state institutions with responsibility for measures aimed at reducing the effects of climate change.

10

Effects of atmospheric circulation on water temperature along the southern Baltic Sea coast

Girjatowicz Józef Piotr, Świątek Małgorzata

Oceanologia

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2019

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No. 61 (1)

38--49

EN

The relationships between atmospheric circulation patterns and water surface temperature along the coast of the southern Baltic Sea were studied. Seasonal water temperature values for Świnoujście, Międzyzdroje, Kołobrzeg, Władysławowo, Hel and Gdynia stations measured during the period of 1951-2010 were used. The methods of correlation and regression were applied to determine the relationships between water temperature and the number of days of atmospheric circulation patterns. It was demonstrated that the strongest relationships occur in winter, chiefly on account of intense atmospheric circulation activity and weaker effects of solar radiation. The relationships with western circulation are slightly stronger than that associated with the eastern circulation. During the remaining seasons, those dependencies are clearly weaker. Asynchronous relationships between water temperature and atmospheric circulation are less pronounced than the synchronous ones. Despite being weaker, the asynchronous relations are still statistically significant, mainly in the spring season and as such, they may have a prognostic significance.

11

A multifaceted analysis of the relationship between daily temperature of river water and air

Graf Renata

Acta Geophysica

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2019

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Vol. 67, no. 3

905--920

EN

The aim of the study was to establish the strength and direction of the relationship between daily temperature of river water and air with the use of selected estimation methods. The relationship was assessed for the River Noteć and its tributaries (Western Poland), using the cross-correlation function and Granger causality. The study established cause-and-effect relations for “water–air” and “air–water” directions of influence. It was confirmed that forecasting the pattern of flowing water temperature from changes in air temperature yields better results when done based on data from the previous day. Results of modelling the relationship between data series with the use of the linear and natural cubic splines models confirmed the presence of a nonlinear relation. It was also established that there is a statistically significant correlation of random fluctuations for both temperature series on the same days. This made it possible to confirm the occurrence of short-term connections between water and air temperature. The results can be used to determine the qualities of thermal regimes and to predict temperature of river waters in the conditions of climate change.

12

Impact of climate change on the Curonian Lagoon water balance components, salinity and water temperature in the 21st century

Jakimavičius D., Kriaučiūnienė J., Šarauskienė D.

Oceanologia

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2018

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No. 60 (3)

378--389

EN

The Curonian Lagoon is a shallow water body connected to the Baltic Sea by a narrow navigable strait, which enables an exchange of water of different salinity. The projected climate change together with the peculiarities of mixing water will undoubtedly alter hydrological regime of this lagoon. The study uses three climate model outputs under four RCP scenarios, four sea level rise scenarios and hydrological modelling in order to project the extent to which water balance components, salinity and temperature may change in the future. In order to simulate river inflow, the Nemunas River hydrological model was created using HBV software. In general, the changes of the lagoon water balance components, salinity and temperature are expected to be more significant in 2081-2100 than in 2016-2035. It was estimated that in the reference period (1986-2005) the river inflow was 22.1 km3, inflow from the sea was 6.8 km3, salinity (at Juodkrantė) was 1.2 ppt and average water temperature of the lagoon was 9.2°C. It was projected that in 2081-2100 the river inflow may change from 22.1 km3 (RCP2.6) to 15.9 km3 (RCP8.5), whereas inflow from the sea is expected to vary from 8.5 km3 (RCP2.6) to 11.0 km3 (RCP8.5). The lagoon salinity at Juodkrantė is likely to grow from 1.4 ppt (RCP2.6) to 2.6 ppt (RCP8.5) by the end of the century due to global sea level rise and river inflow decrease. The lagoon water temperature is projected to increase by 2-6°C by the year 2100.

13

Diurnal water temperature dynamics in lowland rivers: A case study from Central Poland

Łaszewski M. A.

Journal of Water and Land Development

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2018

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no. 36

89--97

EN

The paper examines spatial and seasonal variations in diurnal water temperature dynamics in lowland rivers. Temperature data was obtained from digital temperature loggers located in nine sites across the Mazovian Lowland during the hydrological year 2016. On the basis of measurement data, mean, maximum, and minimum daily ranges were calculated in the monthly timescale, as well as the timing of extreme temperatures during the day. The results indicate that water temperature dynamics of lowland rivers have a clear seasonal pattern, with the highest variations of temperature in May and June and the lowest in January. Statistically significant differences were found in the daily temperature range between groups of the investigated sites; a higher diurnal temperature range was observed in sites draining a smaller catchment area, while larger rivers were generally more thermally stable in the daily timescale. There was also found an effect of anthropopressure on diurnal temperature dynamics in urbanized catchments, mainly due to impoundments and sewage inflows. Maximum water temperature in the studied sites usually occurred in the morning, from 06:00 to 10:00 CEST, while minimum temperature occurred in the late afternoon, from 14:00 to 18:00 CEST. Spatially, the timing of the maximum and minimum water temperatures during the day was similar in all of the investigated sites, with no statistically significant differences. However, cluster analysis indicated that in the summer half of the year the timing of the extreme temperatures was more varied between investigated sites. The results provide new insight into short-term river thermal behaviour and they are valuable in the context of game fisheries due to the significance of daily temperature variations in fish activity and feeding.

PL

Celem pracy było określenie przestrzennego i sezonowego zróżnicowania dobowej dynamiki temperatury wody w niewielkich rzekach nizinnych. Dane pomiarowe uzyskano za pomocą cyfrowych rejestratorów temperatury wody, które zlokalizowano w dziewięciu profilach rzek Mazowsza w roku hydrologicznym 2016. Na podstawie danych pomiarowych obliczono średni, maksymalny i minimalny dobowy zakres temperatury w ujęciu miesięcznym, a także względną częstość występowania ekstremalnych wartości temperatury w poszczególnych godzinach. Wyniki wskazują, że dobowa dynamika temperatury wody odznaczała się wyraźną sezonową zmiennością; największe dobowe wahania temperatury wody były obserwowane w maju i czerwcu, natomiast najmniejsze w styczniu. Wykazano ponadto istotne statystycznie różnice zakresu dobowego temperatury wody między analizowanymi profilami; większy zakres dobowy był charakterystyczny dla profili pomiarowych zamykających zlewnie o mniejszej powierzchni, natomiast większe rzeki były na ogół bardziej stabilne termicznie. Stwierdzono również wyraźny wpływ antropopresji na dobową dynamikę temperatury wody, przede wszystkim w postaci zrzutów wody ze stawów oraz zbiorników, jak również ścieków z oczyszczalni. Temperatura minimalna występowała w przypadku badanych rzek najczęściej rano – od 06:00 do 10:00 CEST, natomiast temperatura maksymalna późnym popołudniem – od 14:00 do 18:00 CEST. Okres występowania ekstremalnych wartości temperatury wody w ciągu dnia był zbliżony; metoda aglomeracji wykazała jednak, że w półroczu letnim zaobserwowano większe zróżnicowanie czasu występowania wartości ekstremalnych, szczególnie temperatury maksymalnej. Wyniki badań wzbogacają wiedzę dotyczącą warunków termicznych wód płynących, wydają się również interesujące w kontekście wędkarstwa sportowego oraz rybactwa.

14

Zmiany temperatury wody w Prośnie w latach 1965-2014

Ptak M., Nowak B.

Woda-Środowisko-Obszary Wiejskie

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2017

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T. 17, z. 3

101--112

PL

Celem pracy jest analiza zmian warunków termicznych rzeki Prosny w środkowej Polsce (profil Bogusław) w ciągu ostatnich 50 lat (1965–2014). Na podstawie codziennych pomiarów temperatury prowadzonych przez Instytut Meteorologii i Gospodarki Wodnej – Państwowy Instytut Badawczy stwierdzono, że średnia roczna temperatura wody rzeki Prosny uległa znacznemu ociepleniu, średnio 0,27°C∙dek–1. W układzie miesięcznym najwyższy wzrost odnotowano w kwietniu – 0,46°C∙dek–1. Zmiany temperatury wody były silnie uzależnione od transformacji warunków klimatycznych. Wzrost średniej rocznej temperatury powietrza w tym samym wieloleciu mierzonej na stacji Kalisz (ok. 20 km od profilu badawczego) wyniósł 0,3°C∙dek–1. Tak wyraźne zmiany reżimu termicznego Prosny mają i będą miały wpływ na funkcjonowanie całego ekosystemu. Jest to dobrze widoczne, m.in. w występowaniu zjawisk lodowych, których czas trwania uległ skróceniu o 5,6 dni•dek–1.

EN

The objective of the paper is the analysis of changes in the thermal conditions of the Prosna River in central Poland (station Bogusław) over the last 50 years (1965–2014). Based on daily temperature measurements performed by the Institute of Meteorology and Water Management – National Research Institute, it was determined that the mean annual water temperature in the analysed river considerably increased by an average of 0.27°C∙decade–1. In monthly distribution, the highest increase was recorded in April. It amounted to 0.46°C∙decade–1. Changes in water temperature were strongly dependent on the transformation of climatic conditions. An increase in the annual air temperature in the analogical multiannual for station Kalisz (about 20 km from the research site) amounted to 0.3°C∙decade–1. Such evident changes in the thermal regime of the Prosna Regime have and will have an effect on the functioning of the entire ecosystem. It is clearly visible among others in the occurrence of ice phenomena the persistence of which decreased by 5.6 day∙decade–1.

15

Badania zmienności i zależności temperatury wód podziemnych od wód rzecznych na ujęciach infiltracyjnych

Przybyłek J., Kasztelan D.

Przegląd Geologiczny

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2017

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Vol. 65, nr 11/2

1356--1362

EN

The paper presents the results ofmeasurements of groundwater and surface water temperature in the area of the Krajkowo water intake. The influence of extreme natural phenomena on Warta River in Krajkowo on the conditions of exploitation of the shore barrier and the radius well are shown. Changes in the velocity of water flow from the Warta River to the well of the shore barrier has been noticed. Such results shown an important role of protective monitoring of a water capture.

16

Zmiany temperatury wody i zjawisk lodowych rzeki Ner (centralna Polska) w latach 1965-2014

Ptak M.

Polish Journal for Sustainable Development

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2017

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T. 21, cz. 1

49--56

PL

W pracy przedstawiono długookresowe zmiany temperatury wody i warunków zlodzenia rzeki Ner położonej w centralnej Polsce. Stwierdzono, że w ciągu ostatnich pięćdziesięciu lat nastąpił znaczny wzrost temperatury wody, który wynosił 0,24 °C · dek-1. Wzrost ten był statystycznie istotny na poziomie p=0,05. W układzie miesięcznym najwyższy wzrost temperatury odnotowano w lipcu (0,37 °C · dek-1), kwietniu (0,35 °C · dek-1) oraz grudniu i styczniu (0,34 °C · dek-1). W dwóch przypadkach (wrzesień i październik) odnotowano niewielkie tendencje ujemne, lecz były one statystycznie nieistotne. W odniesieniu do terminów powstawania zjawisk lodowych można stwierdzić, że analizowanym okresie nastąpiło ich opóźnienie o 1,9 dnia·dek-1. Z kolei zakończenia zjawisk lodowych cechowały się tendencją ujemną nastąpiło przyspieszenie terminu ich końca o 2,5 dnia·dek-1. W związku z tym, skróceniu uległ czas trwania zjawisk lodowych. Odnotowane zmiany są pochodną współoddziaływania czynników naturalnych oraz antropopresji.

EN

The paper presents long-term changes in water temperature and ice conditions in the Ner River located in Central Poland. A considerable increase in water temperature has been determined over the last fifty years, amounting to 0.24 °C dek-1. The increase was statistically significant at a level of p=0.05. In the monthly scale, the highest increase in temperature was recorded in July (0.37 °C dek-1), April (0.35 °C dek-1), and December and January (0.34 °C dek-1). In two cases (September and October), a slight negative tendency was recorded, although it was not statistically significant. In reference to the terms of appearance of ice phenomena, a delay by 1.9 day·dek-1 was determined in the analysed period. The cessation of ice phenomena showed a negative tendency – they ceased earlier by 2.5 day·dek-1. Due to this, the persistence of ice phenomena was reduced. The recorded changes are a result of an increase in air temperature and anthropopressure.

17

Dynamics of the daily course of water temperature in Polish lakes

Skowron R., Piasecki A.

Journal of Water and Land Development

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2016

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no. 31

149--156

EN

The study focuses on short-term changes in surface water temperature in Polish lakes, and is based upon the experimental measurements of water temperature conducted every 60 minutes during the years 1971–2015. 19 lakes were selected on the grounds of their morphometric properties. The examinations were carried out in the system of expeditionary measurements (up to 8 days) and stationary measurements (over 2 months), and included temperature of surface water and its vertical distribution. The analysis of the results showed that temperature differences of water (daily amplitudes) were observed in both time and spatial distribution. The biggest differences in water temperature occurred during spring warming, and often reached 4–5°C, while rarely exceed 2°C in the remaining periods of the yearly cycle. The mean day value occurs twice; in the morning between 8:00 (7:00 GMT) and 11:00 (10:00 GMT), and in the evening at 20:00 (19:00 GMT) and 22:00 (21:00 GMT). Daily changes in the vertical distribution of water temperature are clearly visible down to the depth of 2.5–3.5 m, whereas are just perceptible to the depth of 5.5–7.0 m.

PL

Praca dotyczy krótkotrwałych zmian temperatury wody powierzchniowej w jeziorach w Polsce. Została ona opracowana na podstawie eksperymentalnych pomiarów temperatury wody prowadzonych co 60 minut w latach 1971–2015 w 19 jeziorach wytypowanych na podstawie cech morfometrycznych. Badania prowadzono w systemie pomiarów ekspedycyjnych (do 8 dni) i stacjonarnych (ponad 2 miesiące) i obejmowały temperaturę powierzchniową wody oraz jej pionowy rozkład. Na podstawie analizy wyników stwierdzono różnice temperatury wody (amplitudy dobowe) zarówno w rozkładzie czasowym, jak i przestrzennym. Największe różnice temperatury wody występowały w okresie wiosennego nagrzewania i często osiągały 4–5°C, natomiast w pozostałych okresach cyklu rocznego rzadko przekraczały 2°C. Na podstawie cogodzinnych pomiarów temperatury wody można stwierdzić, że temperatura przed południem między godziną 8:00 a 11:00 (7:00 a 10:00 GMT) oraz późnym wieczorem w godzinach 20:00–22:00 (19:00–21:00 GMT) była najbardziej zbliżona do średniej dobowej. Zmiany dobowe w rozkładzie pionowym temperatury wody wyraźnie zaznaczają się do głębokości 2,5–3,5 m, natomiast dostrzegane są do głębokości 5,5–7,0 m.

18

Wpływ niewielkich zbiorników na temperaturę wody rzek nizinnych na przykładzie Jeziorki i Rządzy

Łaszewski M.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2015

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Vol. 24, No. 1

13--25

PL

W pracy dokonano analizy wpływu niestratyfikowanych zbiorników wodnych na transformację ustroju termicznego niewielkich rzek nizinnych w letnim półroczu hydrologicznym 2014 roku. Pomiary terenowe przeprowadzono na przykładzie zbiornika w Głuchowie na rzece Jeziorce i zbiornika w Rządzy na rzece Rządzy za pomocą cyfrowych rejestratorów temperatury. Poniżej zbiorników stwierdzono wyraźne podwyższenie średnich, maksymalnych i minimalnych miesięcznych wartości temperatury wody. Wykazano także znaczne skrócenie czasu trwania optymalnej temperatury wody dla pstrąga potokowego oraz wydłużenie czasu trwania górnej początkowej temperatury letalnej dla narybku pstrąga. Wnioski wydają się szczególnie cenne z punktu widzenia optymalizacji gospodarki rybacko-wędkarskiej.

EN

The paper presents an analysis of the impact of unstratified water reservoirs on stream thermal regime transformation in the summer period of the hydrological year 2014. Field measurements were carried out using digital temperature data loggers on the example of the Głuchów reservoir (Jeziorka river) and Rządza reservoir (Rządza river). Results showed a clear increase in the average, maximum and minimum monthly values of water temperature below the reservoirs. It was also found that below the reservoirs duration of the brown trout thermal optimum was sig- nificantly decreased and the duration of the upper incipient lethal temperature for brown trout fries was slightly increased. Conclusions appear to be particularly valuable in the context of optimizing fisheries management.

19

Thermal and Oxygen Conditions in Carp Ponds During the Summer Period

Wiśnios M., Kanownik W.

Journal of Ecological Engineering

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2015

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Vol. 16, nr 5

144--150

EN

The work presents changes of oxygen indices in carp ponds during the summer season. The basis of the research were regular water tests conducted in two ponds: Mydlniki II intended for carp farming in the second year of fish production cycle and Bocian used for carp farming in the third (final) year of breeding. The temperature of pond water in July and August was optimal for development and farming of cyprinid fish and ranged from 16.6 to 30.5 °C. The lowest value of oxygen dissolved in water (6.4 mg·dm sup>-3) was registered in Mydlniki II pond and was higher than the oxygen optimum for carp (5 mg·dm sup>-3). Oxygen saturation in water of fish ponds exceeded the optimum upper limit value (168%) on a few dates, however, it posed no lethal threat for fish. In August in Bocian pond oxygen saturation fell within the range of optimal values, creating better conditions for fish development. In the secondary pond (Mydlniki II) it was found that oxygen saturation in water on 12 dates was lower than the low optimal value (96%).

20

Effect of the North Atlantic Oscillation on the Thermal Characteristics of Lakes in Poland

Wrzesiński D., Choiński A., Ptak M.

Acta Geophysica

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2015

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Vol. 63, no. 3

863--883

EN

This paper presents the effect of the North Atlantic Oscillation (NAO) on the thermal characteristics of lakes in Poland. In the analysis, the use was made of monthly air temperatures recorded at fifteen meteorological stations, water temperatures of twelve lakes, and Hurrell’s winter NAO indices. Over the study period (1971-2010), there was a marked increase in the temperatures of both, air and lake waters. Depending on the NAO phase, water temperatures were observed to depart from mean values, being markedly higher than average (even by 1°C) in the positive winter NAO phase. The differences in water temperatures were statistically significant in the winter-spring season. In turn, in the negative NAODJFM phase lake water temperatures in winter and spring were markedly lower than average (in March even by 1.0°C). The unique response of some lakes depends on their morphometric parameters, including their mean depth.