Mathematical modelling as a tool for the assessment of impact of thermodynamics on the algal growth in dam reservoirs – case study of the Goczalkowice Reservoir

Depending on climate conditions, bathymetry, basin morphology, management practices and other factors, some reservoirs are more or less prone to stratification, which can strongly affect both chemical and biological status of water. In the Goczalkowice Reservoir (the biggest dam reservoir in the south of Poland), water quality parameters, such as chlorophyll a concentration, change very dynamically. In the presented study, the Estuary, Lake and Coastal Ocean Model (ELCOM) was applied to simulate water thermodynamics in a period of summer and autumn when the highest concentrations of chlorophyll a were observed, based on the continuous water monitoring in the ZiZOZap project (Łaszczyca et al., 2011). The purpose of the application of ELCOM was to simulate the thermal stratification in the reservoir and to prepare a basis for analyses of the relationship between water thermodynamics and quality. Simulations allowed the identification of several short water mixing events in summer and the final mixing event at the end of summer. The study also included the first application of model results to analyse the relation of changes in water temperature with observed concentration of chlorophyll a (ChlA). Analysis confirmed that each water mixing event was followed by a significant increase in ChlA concentration

Multi-Faceted Environmental Analysis to Improve the Quality of Anthropogenic Water Reservoirs (Paprocany Reservoir Case Study)

Maintaining good condition of dam reservoirs in urban areas seems increasingly important due to their valuable role in mitigating the effects of global warming. The aim of this study is to analyze possibilities to improve water quality and ecosystem condition of the Paprocany dam reservoir (highly urbanized area of southern Poland) using current data of the water parameters, historical sources, and DPSIR (Driver–Pressure–State–Impact–Response) and 3D modeling concerning human activity and the global warming effects. In its history Paprocany reservoir overcame numerous hydrotechnical changes influencing its present functioning. Also, its current state is significantly influenced by saline water from the coal mine (5 g L -1 of chlorides and sulphates) and biogenic elements in recreational area (about 70 mg L -1 of chlorate and to 1.9 mg L -1 Kjeldahl nitrogen) and in sediments (222.66 Mg of Kjeldahl nitrogen, 45.65 Mg of P, and 1.03 Mg of assimilable phosphorus). Concluding, the best solutions to improve the Paprocany reservoir water quality comprise: increasing alimentation with water and shortening the water exchange time, restoration of the 19th century water treatment plant, and wetlands and reed bed area revitalization. The study also proved the applicability of mathematical models in planning of the actions and anticipating their effciency

Phytoplankton production in relation to simulated hydro- and thermodynamics during a hydrological wet year – Goczałkowice reservoir (Poland) case study

Phytoplankton is one of the crucial components of water body ecosystems. Its presence and development depend on biological, physical and chemical factors and in consequence it is an important indicator of ecosystem condition. Monitoring of phytoplankton production, measured as chlorophyll a concentration, is a useful tool for assessing the status of dam reservoirs. Modeled chlorophyll a concentrations are used as water quality indicators in locations not included in monitoring systems, in situations when the temporal resolution of the monitoring is not enough, and in assessments of the impacts of future activities. Therefore, the aim of this study was to find correlations between hydro- and thermodynamics and the chlorophyll a concentration for possible application in reservoir monitoring and management, using an ELCOM-CAEDYM model. The analysis included summer and fall which are most prone to algal blooms, and four phytoplankton groups identified as dominant in the reservoir based on periodic observations. Comparisons of simulated water temperature and both observed and simulated chlorophyll a concentrations confirmed that these variables are significantly correlated (correlation of hourly chlorophyll a and water temperature was 0.70, ranging from 0.55 to 0.81 in the bottom and surface water layers, respectively, while for daily outputs it was 0.74, ranging from 0.60 to 0.83). This relation was stronger than that of chlorophyll a to nutrient (N, P and Si) concentrations. What is more, the method used allowed the assessment of a much more detailed spatial and temporal distribution of phytoplankton groups compared with conventional monitoring techniques. The study indicated that the phytoplankton community was dominated by Chlorophytes and Diatoms with a larger share of Chlorophytes in shallow parts of the reservoir. This domination was weaker after short water mixing events in summer and especially after the fall turnover. The increase in phytoplankton diversity was estimated to occur mainly near the surface and in shallow parts of the reservoir. Most of the observed concentrations of individual phytoplankton groups differed from simulation results by less than 25% and the model reflected accurately 74% of observed trends in concentrations. Calculated chlorophyll a concentration was well matched to hourly monitoring data (mean squared error = 5.6, Nash–Sutcliffe model efficiency coefficient = 0.51, Pearson correlation coefficient = 0.72 and p-value = 0.0007). High compatibility of the model to the values measured in the reservoir make it a promising tool for the prediction and planning of actions aimed at maintaining good functioning of the reservoir

Trends and patterns in surface water chemistry in Europe and North America between 1990 and 2016, with particular focus on changes in land use as a confounding factor for recovery

The report presents trends in sulphate, nitrate, chloride, base cations, ANC (acid neutralising capacity), pH and DOC at circa 500 ICP Waters sites in Europe and North America for the period 1990-2016. Time series were analysed for trends in annual median values, annual extreme values and change points, that indicate years with sudden changes in trend or level. Also provided is a brief overview of possible implications of land use change for recovery of acidified surface waters

Mathematical modelling as a tool for the assessment of impact of thermodynamics on the algal growth in dam reservoirs – case study of the Goczalkowice Reservoir

Depending on climate conditions, bathymetry, basin morphology, management practices and other factors, some reservoirs are more or less prone to stratification, which can strongly affect both chemical and biological status of water. In the Goczalkowice Reservoir (the biggest dam reservoir in the south of Poland), water quality parameters, such as chlorophyll a concentration, change very dynamically. In the presented study, the Estuary, Lake and Coastal Ocean Model (ELCOM) was applied to simulate water thermodynamics in a period of summer and autumn when the highest concentrations of chlorophyll a were observed, based on the continuous water monitoring in the ZiZOZap project (Łaszczyca et al., 2011). The purpose of the application of ELCOM was to simulate the thermal stratification in the reservoir and to prepare a basis for analyses of the relationship between water thermodynamics and quality. Simulations allowed the identification of several short water mixing events in summer and the final mixing event at the end of summer. The study also included the first application of model results to analyse the relation of changes in water temperature with observed concentration of chlorophyll a (ChlA). Analysis confirmed that each water mixing event was followed by a significant increase in ChlA concentration

Comprehensive approach to Upper Silesian reservoir water quality issues. Case study: the Paprocany Reservoir in Tychy, Southern Poland

tekst w j. pol. i ang.Celem prac było przygotowanie programu działań i możliwych rozwiązań, prowadzącego do poprawy jakości wód Jeziora Paprocańskiego i uwzględniającego wieloaspektowego podejścia do przyczyn obserwowanych problemów

Regional assessment of the current extent of acidification of surface waters in Europe and North America

Project manager Kari AustnesThe current status of surface water acidification related to air pollution in Europe and North America has been assessed using country reports, monitoring data, critical loads and exceedance data, acid sensitivity and deposition maps, and data reported under the European Commission’s Water Framework Directive (WFD). Acidification is still observed in many countries, but the extent and severity vary. Maps of acid sensitivity and deposition suggest that surface water acidification is present in regions and countries for which no data or reports were delivered for the current assessment. Existing national monitoring varies in the ability to assess the spatial extent of acidification and the recovery responses of acidified sites. The monitoring requirements under the European Union’s National Emission Ceilings Directive are expected to reverse the recent decline in the number of monitoring sites observed in some countries. The information reported under the WFD is currently of limited value in assessing the extent of acidification of surface waters in Europe. Chemical recovery in response to reductions in acid deposition can be slow, and biological recovery can lag severely behind. Despite large and effective efforts across Europe and North America to reduce surface water acidification, air pollution still constitutes a threat to freshwater ecosystems.Norwegian Environment Agency (Miljødirektoratet) United Nations Economic Commission for Europe (UNECE)publishedVersio