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EN
Nutrients are substances that are used by living organisms in the growth and survival of organisms. On the basis of this background, the aim of this study was to assess the concentration of nutrients (macro and micronutrients) and chlorophyll in the Menjer lake and to examine the relationship between nutrient concentration and algal biomass to identify the determinants of algal development in tropical lakes (Menjer Lake Wonosobo, Indonesia). The research was conducted using a survey method at Menjer Lake Wonosobo. Observations and sampling were carried out 3 times with intervals of 1 month at 7 locations in the photic zone. The concentrations of macronutrients and micronutrients in the Menjer Lake were spatially even in all locations and the temporally slightly increased concentrations were relatively the same during the measurement period. The Cu, NO2, Si, and Na macronutrients are the determining factors for algal blooming in Menjer Lake Wonosobo. The effect of Cu, NO2 and Si concentrations was inversely related to the algal abundance, while the Ca, Na and Mo concentrations were in line with the abundance of algae.
EN
The marine diatom Chaetoceros muelleri is commonly used for aquacultural feed and is well known for its fast growth and easy maintenance. In order to evaluate the potential of C. muelleri to be used for the nutrient removal and biomass production from eutrophic saline wastewaters, the algae were cultured under a wide range of temperature, salinity, photoperiod, and light intensity. The optimum temperature for the biomass production was observed at 30°C, but the algae could maintain at least 66% of the highest production between 20°C and 35°C. The optimum salinity for the biomass production was 25, but the algae could maintain at least 22% of the highest production between 10 and 30. Both light intensity and photoperiod affected the algal biomass production, and the minimum light requirement was considered 100 μmol m−2•s−1 for 6 hours to maintain the biomass production and nitrogen (N) and phosphorus (P) absorption. Throughout all the experiments, the N and P absorption increased with the biomass production, but the ratio of N and P to the biomass exponentially decreased with the biomass production. These results showed that C. muelleri is tolerant to the wide range of environmental conditions, absorbing nutrients and producing organic matter. C. muelleri has a great potential to be introduced in the water treatment processes, especially where the temperature and salinity fluctuate.
EN
The aim of this paper was to evaluate the influence of anthropogenic pollution on the water quality of the Ciemięga River, which flows through the Jastków commune, located in the Lublin Province in the South-Eastern Poland. The analyses of the river water were conducted in the years 2019–2020. Each year, the samples for physicochemical analyses were collected seasonally (in February, May, August and November) from the seven selected Ciemięga River sampling points found in the following localities: Ożarów, Moszenki, Sieprawice, Jastków, Snopków and Jakubowice Konińskie. In addition, 3 series of microbiological analysis were conducted in 2020. Electrolytic conductivity, total phosphorus, nitrate-nitrogen and sulfates constituted the physicochemical indicators of poor water quality in the river. Their average values exceeded the standards for the 2nd class of water quality. High concentration of these indicators, especially of the total phosphorus, could have been related to the influx of domestic wastewater from agricultural holdings, wastewater flows from agricultural areas as well as soil erosion and leaching. The levels of E. coli bacteria and fecal coliform allocated the Ciemięga River waters to the 4th class of water quality and could result from domestic wastewater flow to the river. In order to improve the water quality of the Ciemięga River, it is necessary to reduce or eliminate point and non-point sources of pollution by means of streamlining of the agricultural areas fertilization, regulating the water and wastewater management, regulating of the waste management, as well as the appropriate spatial policy and landscaping of the water catchment areas.
EN
Human disturbance and nutrient runoff lead to water pollution, particularly in downstream waters and reservoirs. We hypothesized that increased human activity in summer would affect the trophic state of downstream reservoirs, affecting the interannual species composition of rotifers. We used long-term data for the Unmun Reservoir in South Korea (2009–2015), which is increasingly affected by human activity. The interannual variation of nitrogen and phosphorus levels was higher in summer and autumn, resulting in eutrophication. This led to a change in species composition of rotifers. Anuraeopsis fissa, Brachionus calyciflorus and Trichocerca gracilis were abundant in the most eutrophic state, while high densities of Ascomorpha ovalis and Ploesoma hudsoni were observed when nutrient concentrations were lower. The trophic state changes in the Unmun Reservoir were largely attributed to summer human activity in tributary streams. Our study location is typical of the stream network in South Korea and we assume that similar trophic state changes in reservoirs will be common. Changes in the density and species diversity of rotifers due to eutrophication indicate the need for active management and conservation, including the restriction of human activity around streams.
EN
Long-term changes in hydrochemistry and community structure of phytoplankton and macrophytes were analyzed in the Sestroretskiy Razliv reservoir (northwestern Russia). The average content of total phosphorus (TP) in May–October increased from 73 μg P l-1 in 1980 to 163 μg P l-1 in 2000. A significant increase in average chlorophyll a content from 16.6 μg l-1 in 1980 to 84.7 μg l-1 in 2000 and a shift in phytoplankton composition to the dominance of cyanobacteria over diatoms indicated a change in the trophic status of the reservoir from meso-eutrophic to hypertrophic. In 2016 and 2018, average TP was 96 and 101 μg P l-1, respectively. The average content of chlorophyll a was 43.6 μg l-1 in 2016 and 66.6 μg l-1 in warmer 2018, indicating persistent eutrophic conditions. Diatoms dominated both in 2016 and 2018, especially in 2016 characterized by unfavorable weather conditions. Cyanobacteria were more abundant in 2018 with higher summer temperatures. The decline of the total area covered by aquatic vegetation from 157 ha in 1980 to 76 ha in 2016 likely resulted from an increase in phytoplankton biomass and water turbidity. Based on the results of our observations, in addition to further reduction in nutrient loading, biomanipulation by introducing predatory fish as a restoration measure was proposed to improve the ecological status of the reservoir.
EN
The BONUS MIRACLE project focuses on understanding the of the impact of climate change on water environments, including it’s affects on hydrological regimes and nutrient concentrations. The overall objective of MIRACLE is to initiate a social learning process in collaboration with stakeholders, that can identify new configurations for governance (conceptual, institutional, and practice based) in order to reduce nutrient enrichment and flood risk in the Baltic Sea region. These configurations should be understood as new solutions to protect water resources, ecosystem services and provide win-win solutions. To achieve this environmental modelling of the Reda catchment, Poland, is used as a pilot study for the project. Mathematical models which specified the detailed processes associated with water cycles, including determining interconnections and quantifying variables characteristic to the assessment of the water resource quantity and quality, were found to be useful. Due to the complexity of some models, launching, entering the appropriate data in the correct formats and calibrating the models proved to be challenging. Future developments in the water management sector should concentrate on specific local catchment areas where the application of integrated water resource management principles and the adaptation to climate change are more easily merged with local spatial planning. However, a larger number and higher frequency of measurements would be required.
PL
Rozwój satelitarnych technologii obserwacji powierzchni ziemi stwarza możliwości wdrożenia nowoczesnych narzędzi monitoringu jakości wód powierzchniowych. W niniejszym artkule zaprezentowano wyniki badań, których celem było opracowanie zautomatyzowanej metody pomiaru eutrofizacji wód śródlądowych. Przeanalizowano zalety i ograniczenia przedmiotowej technologii oraz oceniono potencjalne możliwości jej wykorzystania. Podstawowym wskaźnikiem stanu troficznego wód powierzchniowych jest koncentracja chlorofilu-a w wodzie. W ramach przeprowadzonych badań uzyskano silny związek pomiędzy wartościami koncentracji chlorofilu-a określonych na podstawie standardowych metod pomiarowych, a wartościami tego parametru obliczonymi na podstawie satelitarnych danych spektralnych. Przedstawiono także funkcjonalności opracowanego oprogramowania pozwalającego na automatyczny pomiaru eutrofizacji wód śródlądowych za pomocą teledetekcji. Pomimo szeregu ograniczeń technologii, wykazano wysoki potencjał aplikacyjny przedmiotowego rozwiązania.
EN
The development of satellite technologies for observing the earth’s surface creates the possibility of implementing modern tools for surface waters quality monitoring. This article presents the results of the research aimed at developing an automated method for assessment of the eutrophication of inland waters. The advantages and limitations of the technology were analyzed and the potential possibilities of its application were described. The basic indicator of the trophic state of surface waters is the concentration of chlorophyll-a in the water. As result of the research, a strong relationship was obtained between the chlorophyll-a concentration values determined on the basis of standard measurement methods, and the chlorophyll-a values calculated on the basis of satellite spectral data. The functionalities of the developed software for automated measuring eutrophication of inland water using temote sensing were also presented. Despite a number of limitations of the technology, high application potential of the solution has been demonstrated.
PL
W artykule przestawiono związki pomiędzy nadmiernymi substancjami biogennymi zawartymi w ściekach i osadach ściekowych, w tym w odciekach z przeróbki osadów, a procesem eutrofizacji wód powierzchniowych, wraz z jego skutkami środowiskowymi. Nadmiar substancji biogennych wywiera wpływ na znaczne przyspieszenie eutrofizacji. Ścieki i osady ściekowe, wraz ze spływami obszarowymi, uznane zostały za istotne źródła zanieczyszczeń biogennych, stąd niezbędne stało się ich efektywne usuwanie i odzysk, szczególnie fosforu.
EN
The article presents the relationship between the excess of nutrients in wastewater and sludge, including in liquors from sludge treatment, and the process of eutrophication of surface waters and its consequences for the environment. The excess of nutrients greatly accelerates the process of eutrophication. Wastewater and sludge, together with non-point sources, are considered as significant sources of nutrients, hence the necessity of their efficient removal and recovery, phosphorus in particular.
PL
W pracy przestawiono związki pomiędzy nadmiernymi substancjami biogennymi, zawartymi w punktowych i obszarowych źródłach, a procesem eutrofizacji wód powierzchniowych, wraz z jego skutkami środowiskowymi. Nadmiar substancji biogennych wywiera wpływ na znacznie przyspieszenie procesu eutrofizacji. Ścieki i osady ściekowe, wraz ze spływami obszarowymi, uznane zostały za istotne źródła zanieczyszczeń biogennych, stąd niezbędne stało się ich efektywne usuwanie i odzysk, szczególnie odzysk fosforu.
EN
The paper presents relations between excess of nutrients from point and non-point sources, causing the process of eutrophication of surface waters and its environmental changes. The excess nutrients greatly accelerate the process of eutrophication, Wastewaters and sludge, together with non-point sources are significant sources of nutrients, therefore its efficient removals and recovery, particularly recovery of phosphorus, are necessary.
PL
Fosfor stanowi podstawowy element utrzymania życia, jednakże gdy wysokie ładunki fosforu i azotu zrzucane są do wód, to wymienione substancje biogenne powodują eutrofizację środowiska wodnego. W pracy przedstawiono przykład największej na świecie instalacji do odzysku substancji biogennych, szczególnie fosforu, poprzez technologię krystalizacji struwitu z odcieków z przeróbki osadów ściekowych w Metropolitarnym Rejonie Odzyskiwania Wody Wielkiego Chicago.
EN
Phosphorus is an essentials element to sustain life, however when high loads of phosphorus and nitrogen are discharged to water bodies, these nutrients result in eutrophication of aquatic environment. In this article, an example of the biggest in the world installation for nutrients recovery, particularly on the implementation phosphorus recovery from sludge treatment liquors by struvite crystallization technology, in Metropolitan Water Reclamation District of Greater Chicago, is presented.
PL
Nawozy sztuczne stosowane w rolnictwie negatywnie wpływają na jakość wód, zarówno powierzchniowych, jak i podziemnych. Zatoka Pucka jest szczególnie narażona na eutrofizację spowodowaną napływem substancji odżywczych, ponieważ jest otoczona terenami intensywnie wykorzystywanymi w rolnictwie. Na wybrzeżu znajduje się także wiele ośrodków turystycznych. Strumienie i rzeki łatwo przenoszą ładunek azotu i fosforu do morza. W ramach projektu WaterPuck, finansowanego przez Narodowe Centrum Badań i Rozwoju (NCBiR), badano jakość rzek i strumieni płynących przez terytorium Gminy Puck i wpadających do Zatoki Puckiej. Były to: Reda, Kanał Łyski, Kanał Mrzezino, Gizdepka, Potok Błądzikowski, Płutnica i Kanał Młyński. Badane rozpoczęto w lipcu 2017 r., a próbki wody są pobierane co 3-4 tygodnie pobliżu ujść strumieni. Mierzone są stężenia związków azotu (amoniak, azotan(III) i azotan(V)) oraz fosfor ogólny i fosforany. Regularne monitorowanie jakości strumieni umożliwia ocenę sezonowych zmian stężeń składników odżywczych, a także ich rozmieszczenia przestrzennego. Stworzy to podstawę do śledzenia zależności między użytkowaniem gruntów i praktykami rolniczymi a ładunkiem składników odżywczych zrzucanych do Zatoki Puckiej z niepunktowych źródeł zanieczyszczeń. Wstępne wyniki wskazują na znaczące sezonowe zmiany stężeń zanieczyszczeń, prawdopodobnie związane z harmonogramem prac rolniczych. Kolejna część projektu badawczego skupi się na identyfikacji obszarów przyczyniających się do zanieczyszczenia strumieni. Oceniane będą zmiany stężeń składników pokarmowych podczas intensywnych opadów deszczu. Wyniki będą podstawą do modelowania transportu składników pokarmowych wodami powierzchniowymi w gminie Puck.
EN
The ferilizers used in agriculture negatively affect the surface and groundwater quality. The Bay of Puck is a semi-closed part of the Gulf of Gdańsk, which is particularly vulnerable to eutrophication caused by the inflow of nutrient substances. The Bay is surrounded by the lands intensively used in agriculture. Also a number of touristic resorts is located on its coast. The streams and rivers carry the load of nitrogen and phosphorus to the sea. Within the project WaterPuck, financed by the National Centre of Research and Development in Poland (NCBiR), the quality of rivers and streams flowing through the territory of the Puck Community and discharging to the Bay of Puck is being researched. The quality of seven streams: Reda, Kanał Łyski, Kanał Mrzezino, Gizdepka, Potok Błądzikowski, Płutnica and Kanał Młyński is investigated. The researched was started in July 2017. The samples of water are collected every 3-4 weeks at sampling points located close to the streams estuaries. The concentrations of nitrogen species (ammonia, nitrate III and nitrate V) as well as total phosphorus and phosphates are measured. The regular monitoring of streams quality make it possible to assess the seasonal changes of nutrients concentrations as well as their spatial distribution. This will provide the basis for tracking the relationships between the land use and agricultural practices and the load of nutrients discharged to Bay of Puck from non-point sources of pollution. The preliminary results indicate quite significant seasonal variations of pollutants concentrations, probably associated to the time schedule of agricultural practices. The highest concentrations of nutrients where present in sampling points located on Błądzikowski Potok, Kanał Mrzezino as well as Gizdepka – all flowing through arable lands. Concentrations of nitrates V in Błądzikowski Stream varied from 2,27 to 7,55 mg NO3-/dm3, while the concentrations of total phosphorus – from 0,24 to 0,45 mg P/dm3. The next part of the research project is going to focus on identification of areas contributing to the streams pollution. The changes of nutrients concentrations during intensive rainfalls will be evaluated. The results will provide the basis for modelling of nutrient transport with surface waters in the Puck Community.
12
Content available remote Light pollution as an environmental hazard
EN
Light pollution is one of the most widespread but at the same time least noticeable environmental hazards resulting from human activity. It is defined as disturbing the nocturnal environment with light emitted by anthropogenic sources. Light pollution is described as the glare, the trespass, and the sky glow resulting from the scattering of artificial light in the atmosphere. The paper analyses the impact of these three categories on the environment. The results of the long-term research on this problem are presented. It was found that the largest impact on the environment, both direct by the glare and indirect by the sky glow, result from lamps with spherical shields and LED advertising billboards. The possible influence of light pollution on the eutrophication of reservoirs was also researched.
PL
Zanieczyszczenie świetlne jest jednym z najpowszechniejszych, lecz jednocześnie najmniej zauważalnych zagrożeń środowiskowych. Jest ono rozumiane jako zaburzanie nocnego środowiska naturalnego światłem emitowanym przez źródła antropogeniczne. Przejawia się poprzez: olśnienie, zaświecanie oraz łunę świetlną, powstającą wskutek rozpraszania sztucznego światła w atmosferze. Przedstawiono wpływ wymienionych kategorii zanieczyszczenia świetlnego na środowisko naturalne. Zaprezentowano wyniki własnych badań tego zagadnienia. Stwierdzono, że największy wpływ, zarówno bezpośredni poprzez olśnienie, jak też pośredni, poprzez łunę świetlną, mają lampy z kulistymi osłonami oraz reklamowe tablice LED. Zbadano również możliwy wpływ zanieczyszczenia świetlnego na eutrofizację zbiorników wodnych.
EN
Dinoflagellates account for most of the harmful phytoplankton species but relatively little is known about the specific responses of different species to environmental variables. 21 dino-flagellate species were recorded in the plankton of the Neva Estuary since the mid-19th century. 14- year long data of midsummer dinoflagellate biomass was statistically analyzed in the Neva Estuary to show the changes in dinoflagellate species in relation to environmental factors. Biomasses of Dinophysis norvegica (Clapared & Lachmann 1859), Prorocentrum lima ((Ehrenberg) F.Stein 1878) and Peridinium aciculiferum (Lemmermann 1900) had very similar positive relationships with salinity, temperature, phosphorus and suspended particulate organic matter concentrations while the biomass of the other common species Peridinium cinctum ((Müller) Ehrenberg 1832) and Peridinium sp. mostly showed quite opposite trends. Climate fluctuations leading to changes in the environmental variables could significantly affect the composition and productivity of the dinoflagellate community. Biomass of Glenodinium sp. and Peridinium sp. positively correlated with primary production and biomass and chlorophyll a concentration, but did not show a positive relationship with phosphorus. This may be due to the fact that these species in the conditions of the Neva Estuary, apparently, are more consumers than producers of organic matter, feeding on algae and cyanobacteria of phytoplankton. Therefore, to interpret the relationships between the dinoflagellate biomass and environmental variables one should take into account that the species of this group is characterized by mixotrophy and, consequently, their biomass may depend not only on the conditions of autotrophic, but also heterotrophic nutrition.
EN
Beach wrack is a unique issue. It is both an ecological problem for the eutrophicated reservoirs such as the Baltic Sea and the social one associated with nuisance for inhabitants and tourists visiting seaside resorts. This generates a problem for the institutions responsible for beach management (local authorities). Nowadays local authorities generally leave cleaning the beach to local companies and it is not known how the beach wrack material is utilized. According to the current trend, the nuisance of beach wrack should be turned into a resource that will bring benefits. In order to understand what beach wrack really is, it is necessary to establish a specific definition. The material washed out by the sea contains not only the natural substances of organic origin, but also human products: plastics, glass or metals, which in many cases forces to pre-select before using the technology. Good treatment of material the quantities of which are undefined and the occurrence is variable, constitutes a real challenge. The beach wrack processing on reed bed system, so far used mainly for the treatment of sewage sludge, seems to be a good idea. It is an innovative technology that is expected to have similar results as for the processing of sewage sludge from wastewater treatment, i.e. a high nutrient fertilizer. In accordance with European Union recommendations, the possible use of beach wrack as a fertilizer in agriculture or enrichment of compost, will close the circulation of organic matter in environment, thus entering the reed bed system into a circular economy. Many aspects related to the reed bed system favor the use of this technology in the practical processing of marine organic waste.
EN
This paper presents the results of physical and chemical tests of surface water samples taken from the areas of the Ostrzeszów Commune, which is part of the Ostrzeszów County, located in the southern part of the Wielkopolska Province. The Ostrzeszów commune is included in the urban-rural areas. The physicochemical analysis of surface waters covered samples taken from seventeen measurement and control points from places as accessible as possible. The water quality was assessed in accordance with the applicable regulations of the Minister of the Environment. Surface waters were characterized by typical variability for agricultural areas, i.e. slightly alkaline, pH in the range of 7.5-8.45; specific conductivity in the range of 246-512 μS/cm; turbidity in the range of 1.7-10.5 NTU; total hardness in the range of 1.6-3.2 mmol∙dm-3 Ca2+, Mg2+; alkalinity in the range of 66-142 mg∙dm-3 CaCO3 ; chloride content in the range of 19-47 mg/dm3 Cl-; content of biogenic compounds, ie: nitrites in the range of 0.02-0.36 mg∙dm-3 N-NO2 - ; nitrates in the range of 0.05 - 4,9 mg∙dm-3 N-NO3 - ; ammonium ion in the range of 0.04-0.94 mg∙dm-3 N-NH4 + ; the content of orthophosphate in the range of 0.11-1,56 mg∙dm-3 P-PO4 3-. The content of metals, i.e. manganese Mn, Fe iron, was characterized by high variability depending on the location of the sampling site (Mn manganese in the range of 0.006-0.22 mg∙dm-3, Fe iron in the range of 0.02-0.28 mg∙dm-3, potassium K in the range of 10-13 mg∙dm-3). In all analyzed samples, the presence of copper Cu, nickel Ni and zinc Zn was not detected. The quality of surface waters of the Ostrzeszów commune, in addition to natural hydrological factors, is affected by areas covered by agricultural activity and the evident lack of developed sewerage system in the analyzed sampling regions. The research carried out at the turn of the year showed that the use of artificial and natural fertilizers in cultivated areas contributed to the increase in the content of biogenic and mineral substances in surface.
EN
Storage reservoirs are artificially created and in order to function properly, require constant human interference. Zemborzycki reservoir has undergone a successive eutrophication. In 2010, an experimental artificial land surfaces were developed throughout the reservoir. Various native species were transplanted on these lagoons to enrich biodiversity within the reservoir and to reduce phosphorus supply through the plant barrier. The aim of this study was to determine the role of these artificially constructed lagoons and their associated vegetation on phosphorus reduction throughout the reservoir. The reservoir is affected by water rich in phosphorus. In the estuary zone which hosts a developed phytolittoral zone with macrophytes phosphorus load is significantly reduced. In the lagoon area there was also a marked reduction in phosphorus concentration in study years, along with the progressive colonization of plants. The significant reduction of phosphorus compounds in the artificial phytolittoral zone confirms the necessity of such zones. At present, the negative ecological potential of the reservoir and its declining natural and recreational values, it seems justified to separate the so-called natural zone in a reservoir that would serve as a natural biofilter. However, the most important action is to regulate incoming wastewater in the catchment area of the Bystrzyca River. Studied artificial substrates for plants (sand and gravel), although slowly, but gradually settled by water plants, can be a tool supporting the purification of dam reservoir waters. They are also durable and can be shaped in any way, which can be an additional asset – aesthetic.
PL
Zbiorniki retencyjne, utworzone przez człowieka, dla prawidłowego funkcjonowania wymagają ciągłej jego ingerencji. Zbiornik Zemborzycki ulega sukcesywnej eutrofizacji. W roku 2010 zapoczątkowane zostało tworzenie na obszarze zbiornika sztucznych powierzchni roślinnych dla wzbogacania bioróżnorodności. Ich powstanie miało także na celu wyhamowanie wody wpływającej do zbiornika i przez ich przepływ przez powierzchnię roślinną ograniczenie dostaw fosforu. Celem badań było określenie roli sztucznie ukształtowanego fitolitoralu w redukcji fosforu. W tym celu określono ładunek fosforu dopływający do zbiornika ze źródeł powierzchniowych, z wodami rzecznymi oraz ze źródeł zewnętrznych. Do zbiornika wpływa woda bogata w fosfor. W strefie ujściowej rzeki Bystrzycy, w której znajduje się rozwinięta strefa naturalnego fitolittoralu, ładunek fosforu jest znacznie zmniejszony. W strefie lagun odnotowano również znaczne zmniejszenie stężenia fosforu w kolejnych latach badań, wraz z postępującą kolonizacją ich przez rośliny. Znacząca redukcja związków fosforu w sztucznej strefie fitolitoralu potwierdza konieczność ich istnienia. Przy obecnym, złym potencjale ekologicznym zbiornika Zemborzyckiego i obniżających się walorach przyrodniczych oraz możliwościach jego rekreacyjnego wykorzystania, uzasadnione wydaje się wydzielenie tzw. strefy przyrodniczej w zbiorniku, która pełniłaby rolę naturalnego biofiltra. Jednak najważniejszą jest uregulowana gospodarka ściekowa w zlewni rzeki Bystrzycy i zbiornika. Badane sztuczne podłoża dla roślin, chociaż wolno, ale sukcesywnie zasiedlane są przez rośliny, mogą stanowić narzędzie wspomagające oczyszczanie wód zbiorników zaporowych. Są jednocześnie trwałe i mogą być dowolnie kształtowane, co może stanowić dodatkowy atut – estetyczny.
PL
Wyjaśniono pojęcie eutrofizacji wód powierzchniowych, a w szczególności zwrócono uwagę na negatywne skutki tego zjawiska dla ekosystemów jeziornych. Omówiono metodę inaktywacji fosforu uznawaną za jedną z najefektywniejszych metod rekultywacji jezior. Na podstawie pierwiastka wiążącego związki fosforu (wapń, żelazo, glin i lantan) podzielono i scharakteryzowano substancje i preparaty chemiczne, w tym koagulanty, wykorzystywane w tej metodzie. Podano warunki ich stosowania oraz określono wady i zalety chemicznej rekultywacji jezior. Na przykładach z całego świata wskazano jeziora, w których prowadzono inaktywację fosforu oraz przytoczono za literaturą sumaryczną dawkę wprowadzonych do zbiorników wodnych substancji i preparatów chemicznych.
EN
A review, with 62 refs., of coagulants based on selected Ca, Fe, Al or La compds.
EN
The general impact of extra nitrogen on ecological stoichiometry was examined in alpine grasslands on the Tibetan Plateau. Extra nitrogen increased the ratio of nitrogen to phosphorus (N:P ratio) in leaves and aboveground parts of plants by 43.4% and 32.7%, respectively. In contrast, extra nitrogen reduced the ratio of carbon to nitrogen (C:N ratio) in leaves by 30.6%. Extra nitrogen decreased soil C:N ratio by 9.1% in alpine meadows, but increased soil C:N ratio by 3.4% in alpine steppes. Extra urea had a stronger positive impact on aboveground vegetation N:P ratio than did extra ammonium nitrate. Extra urea rather than ammonium nitrate decreased aboveground vegetation C:N ratio and soil C:N ratio. The impact of extra nitrogen on aboveground vegetation N:P ratio was positively correlated with latitude, mean annual temperature and precipitation, nitrogen application rate and accumulated amount, but negatively correlated with elevation, duration and aboveground vegetation N:P ratio of the control plots. The impact of extra nitrogen on leaves N:P ratio was positively correlated with nitrogen application rate and accumulated amount. The impact of extra nitrogen on leaves C:N ratio was positively correlated with latitude, but negatively correlated with mean annual temperature and precipitation, nitrogen application rate, accumulated amount, duration and leaves C:N ratio of the control plots. Therefore, nitrogen enrichment caused by human activities will most likely alter element balance and alpine plants from nitrogen limitation to phosphorus limitation. This effect may weaken with time, and increase with climatic warming, increased precipitation and nitrogen input rate.
EN
Eutrophication of the Baltic Sea is considered a major threat to its ecological status. We present and discuss Polish riverine flow normalized loads of total nitrogen (TN) and total phosphorus (TP) discharged into the Baltic Sea in (i)1988–2014, (ii) periods of maximum TN (1992–1994), TP (1988–1991) emission, (iii) the reference period (1997–2003) established by the Helsinki Commission (HELCOM), (iv) 2012–2014, last years of our study. Despite considerable nutrient load reductions prior to the HELCOM reference period, Poland is expected to reduce TN and TP loads by 30% and 66%, respectively. In the light of our historical and up-to-date findings defining ecological status of the Baltic Sea, we suggest that the proposed TP load reduction is overestimated and its realization may lead to (i) undesirable consequences for the Baltic ecosystem, (ii) would require a decline in TP concentrations to 0.067 mg P dm-3 (the Vistula River) and 0.083 mg P dm-3 (the Oder River), values reported for pre-industrial times. The current nutrient concentrations in the Vistula and Oder safely comply with the requirements of the Water Framework Directive. We also comment on the top-down and bottom-up effect resulting in quantitative and qualitative reorganization of the Baltic ecosystem, a phenomenon already observed in the Baltic Sea.
EN
The trophic state of ten dam reservoirs was assessed using a zooplankton community. In order to determine the trophic state of dam reservoirs, we used indices calculated on the basis of density and species structure of Rotifera and Crustacea communities. Samples were collected once during summer 2012 in ten dam reservoirs. The largest numbers of zooplankton taxa were found in a lowland high meso-eutrophic dam reservoir (Koronowski) and the lowest ones in a submontane low eutrophic dam reservoir (Lubachowski). The trophic state was determined for the investigated dam reservoirs. In the case of the Rotifera community, the percentage of the tecta form in the Keratella cochlearis population and the proportion of high-trophic species in the total species density were the best indices to describe the water trophic status. In the case of the crustacean community, the best indices were the density of Crustacea and the biomass of Cyclopoida. The high value of all indices calculated on the basis of density and species structure of Rotifera and Crustacea was determined for Zygmunt August Lake, whose trophic status was defined as highly eutrophic to polytrophic. Our study has shown that zooplankton could be a good ecosystem indicator of the water trophic level in dam reservoirs.
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