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EN
There have been investigated potential evaluation of equilibrium adsorption isotherm for the removal of nitrates from water solutions using two types of char produced in commercial-scale pyrolysis based on recycled waste rubber tires. Liquid phase adsorption studies were performed under batch conditions and maximum adsorption capacity was determined. Equilibrium data were mathematically modelled using two-parameters Langmuir, Freundlich, three-parameters Redlich-Peterson, Toth, Dubinin-Radushkevich, Radke-Praushnitz, combined Langmuir-Freundlich and four-parameters Fritz-Schlunder, Marczewski-Jaroniec, Bi-Langmuir adsorption models. Obtained results revealed the potential use of the studied char adsorbents for nitrates removal from aqueous media (the maximum adsorption capacity at equilibrium 10.07 mg/g, have been achieved for CH-1 char). The Langmuir-Freundlich isotherm had the best fit for the adsorption experimental data over the whole concentration range. The highest percentage of NO3 removal efficiency onto CH-2 char achieved in NO3 initial concentration range from 26.44 to 66.55mg/L reaching values in the range of from 80.74 to 78.7%.
EN
Nitrogen load is crucial for its application in various fields such as agriculture and improving water quality control for authorities responsible for establishing agricultural policies in the area. The calculation of nitrogen load using existing equations is not applicable for all types of rivers, thus requiring the development of a new equation that can be applied to lakes and rivers in the Biebrza river catchment. To determine the new equation, extensive mapping of the catchment area was conducted, which was adjusted to precipitation and runoff in the area, allowing the observed results to be compared. Based on several analyses, the new equation has better accuracy, RMSE of the new model-based estimation decreased by 65.9% in 2005–2015 and 62.2% in 2016–2021 for river and 92% in 2008–2019 and 95% in 2020–2021 for lakes. Therefore, the application of the new calibrated empirical model provides results close to the real values and it can be used in the Biebrza river basin to simulate the total nitrogen runoff.
EN
At present, the problem of the availability of high-quality fresh water is urgent. The reservoirs from which water is extracted are running low. The amount of fresh water on the planet has decreased significantly in recent years. A big problem for the use of fresh water is its pollution. Groundwater remained relatively clean, but even when used, it needs to be controlled. Goal of research was the quality control of water from ponds and water sources in the National Dendrological Park (NDP) "Sofiyivka" of the National Academy of Sciences (NAS) of Ukraine in terms of physicochemical and bacteriological indicators and a study of the park's hydrosystem. When conducting research, potentiometric, gravimetric, titrimetric, colorimetric and spectrophotometric methods were used. The hydrosystem of the NDP "Sofiyivka" of the NAS of Ukraine, created during the period of its foundation, has basically retained its planning forms and all its artificial structures. The water system is an important environmental factor that contributes to the quality development of plants, and also has an aesthetic value. The analysis of the results of a study of the physicochemical and bacteriological composition of drinking water from the studied water catchments showed that the water is safe for consumption in terms of such indicators as the content of sulfates, nitrites, chlorides, but contains a significant amount of nitrates and has a high hardness, which can contribute to the development of a number of diseases. Long-term consumption of such water will have a negative impact on the human body. In all water samples from the capture, the growth of common coliforms in 100 cm3 and the presence of Escherichia coli were found, which is dangerous when drinking unboiled water and can bring to intestinal infectious diseases. According to the obtained experimental results of the quality of the studied water samples from the Krasnostavsky, Upper and Lower ponds of the NDP "Sofiyivka" NAS of Ukraine, the general physical and chemical indicators fully comply with the established standards, but the results of studies of the ponds in terms of bacteriological indicators, namely the index of lactose-positive E. coli indicate their significant excess and non-compliance with the standards in the Krasnostavsky and Verkhny ponds by 48 and 12 times, respectively.
PL
Dobry stan ekosystemów wodnych ma kluczowe znaczenie dla życia i zdrowia ludzi oraz dla rozwoju gospodarki. Jedną z przyczyn degradacji tych ekosystemów są zanieczyszczenia biogenami, takimi jak azot i fosfor, przyczyniające się do eutrofizacji, a jednym z głównych źródeł tych zanieczyszczeń jest rolnictwo. W artykule przedstawiono zmiany wprowadzone w aktualizacji „Programu działań mających na celu zmniejszenie zanieczyszczenia wód azotanami pochodzącymi ze źródeł rolniczych oraz zapobieganie dalszemu zanieczyszczeniu” w kontekście kierunków polityki Unii Europejskiej i zobowiązań wynikających ze strategii i inicjatyw Europejskiego Zielonego Ładu, takich jak: unijna strategia na rzecz bioróżnorodności 2030, nowy plan działania dotyczący gospodarki o obiegu zamkniętym czy strategia „od pola do stołu”. Artykuł opisuje znaczenie zrównoważonego rolnictwa dla ochrony wód i ograniczenia zjawiska eutrofizacji.
EN
Good status of water ecosystems is of key importance to the life and health of people, as well as to the economic development. One of the reasons behind degradation of these ecosystems is biogenic pollution, including nitrogen and phosphorus, contributing to eutrophication; one of the main sources of this pollution is agriculture. The article presents modifications introduced to the updated "Programme of measures to reduce water pollution with nitrates from agricultural sources and prevention of further pollution" in the context of EU policy directions and obligations resulting from the strategy and initiatives of the European Green Deal, such as: EU Biodiversity Strategy for 2030, new Circular Economy Action Plan, or Farm to Fork Strategy. The article describes the importance of sustainable agriculture for the protection of waters and reduction of the eutrophication phenomenon.
EN
As a rule, nitrates are present in all natural water bodies. Their increased concentrations are connected with the discharge of insufficiently treated wastewater from industrial and communal enterprises, agricultural and livestock complexes. Recent scientific publications concerning treatment methods for nitrates removal from natural water and wastewater were analyzed in order to create effective and low-waste technology for obtaining high quality water. It has been established that the ion exchange method is quite effective for removing nitrates from water. In the paper, the processes of ion exchange removal of nitrates from water on low-axis anionite in DOWEX Marathon WBA in Сl- form were investigated. During the sorption of nitrates with a concentration of 186, 205, 223 and 2200 mg/dm3, it was established that the full exchangeable dynamic capacity was 1.075, 1.103, and 1.195, 1.698 g-eq/dm3, respectively. To regenerate anionite, solutions of ammonia as well as potassium chloride, ammonium chloride and potassium carbonate were used in this work. The choice of potassium and ammonium compounds is due to the prospect of further use of regeneration solutions for the production of liquid fertilizers.
6
Content available remote Ocena zawartości azotanów w mięsie drobiowym poddanym obróbce termicznej
PL
W 10 próbkach mięsa drobiowego (świeżego, pieczonego, gotowanego lub liofilizowanego), pochodzących ze sklepów spożywczych oznaczono zawartość azotanów(III) i azotanów(V). Próbą referencyjną było mięso drobiowe z hodowli domowej. Najmniejszą zawartość azotanów(III) i azotanów(V) stwierdzono w mięsie pochodzącym z wiejskiej (własnej) hodowli drobiu. Suszenie sublimacyjne mięsa drobiowego powodowało utlenianie azotanów(III) do azotanów(V), a gotowanie i pieczenie redukcję azotanów(V) do azotanów(III). Ponadto w mięsie gotowanym stwierdzono istotnie mniejszą zawartość azotanów(III) niż w mięsie pieczonym. W próbkach mięsa gotowanego i pieczonego wykryto jedynie azotany(III), a w próbkach mięsa liofilizowanego wykryto tylko azotany(V).
EN
Nitrate(III) and nitrate(V) were detd. by ion chromatog. in 10 samples of com. poultry meat (fresh, roasted, cooked or freeze-dried). The reference sample was poultry meat from rural (own) breeding. The lowest content of nitrates(III) and nitrates(V) was found in meat from rural (own) poultry farming. Freeze-drying of meat caused the oxidn. of nitrates(III) to nitrates(V), whereas cooking and baking caused the redn. of nitrates(V) to nitrates(III). Moreover, the content of nitrates(III) in the cooked meat was significantly lower than in the roasted meat. Only nitrates(III) were detected in the cooked and roasted meat samples, and only nitrates(V) in the freeze-dried meat samples.
EN
Results of research of six large karstic springs with a discharge rate of 10-100 l/s obtainedfrom a series of 12 measurements in 2021-2022 are the basis for a comparison of the chemical composition in the past and present. The studied springs drain Triassic limestones and dolomites in the southern part of Major Groundwater Basin No. 333 in the Opole region. After 40 years, there is a significant decrease in discharge rates in five out of all selected springs, and frequent dying out of outflows in three cases. A significant increase in the content of nitrogen compounds, espe¬cially nitrates, has been measured. Statistical factor analysis allowed distinguishing two groups of factors responsible for changes in the main ions in groundwater. Restoring high groundwater quality is an urgent task for the administration of this region, which requires a comprehensive approach.
PL
Azotany(III) i azotany(V) są typowymi zanieczyszczeniami wody pitnej, które mają negatywny wpływ na zdrowie ludzi. W pracy oceniono poziom azotanów(III) i azotanów(V) w 29 wodach kranowych i jednej studni wiejskiej na terenie Górnego Śląska. Uzyskane wyniki posłużyły do oceny ryzyka zdrowotnego dla miejscowej ludności. Punkty poboru próbek zostały wybrane tak, aby pomóc w identyfikacji źródła w przypadku wystąpienia podwyższonego poziomu azotanów(III) lub azotanów(V). Dawka azotanów pobranych w wyniku spożycia wody pitnej była wyższa dla dzieci i niemowląt niż dla dorosłych. Iloraz zagrożenia dla kobiet, mężczyzn, dzieci i niemowląt był mniejszy od 1.
EN
Nitrates and nitrites are typical and important contaminants of drinking water that negatively affect people’s health. The paper evaluates the levels of nitrates and nitrites in 29 tap waters and one village well in Upper Silesia. The results were used for health risk assessment for the local communities. The sampling points were chosen so that to help identify the source when an elevated level of nitrites and nitrates is observed. The calculated Chronic Daily Intake values were higher for children and infants than for adults. The Hazard Quotient values for women, men, children and infants were below 1.
EN
The present study indicates the quick response of a shallow aquifer to precipitation. The nitrate content in water from 20 wells was determined. The study showed a significant 1-m decrease in the water table in the studied wells at low precipitation levels (10 mm) in April (wells 13 and 16). In turn, the water table in the wells after the maximum rainfall in September (130 mm) increased by 0.5 m in well 19. The results of the chemical analysis of the water indicate that the permissible nitrate content was highly exceeded in wells 3, 17, and 18. The nitrate content in wells 1 and 2 was almost 50 mg/l, which is the permissible value for drinking water. The precipitation level did not influence the content of nitrates in the well water.
EN
The process of extracting nitrates from water by the methods of reverse osmosis and ion exchange was investigated in the paper. In the formation of reverse osmosis, low-pressure membranes were used, and in ion-exchange processes, highly alkaline anionite AB–17–8 was applied in salt form. The dynamics of changes in the concentration of nitrates in the permeate and the concentration with an increase in the degree of permeate selection from 9 to 90% at initial nitrate concentrations of 18, 50 and 100 mg/dm3 were determined. The indicators of selectivity and productivity of membranes were calculated depending on the degree of permeate selection. It was shown that the low-pressure reverse osmosis membrane is characterized by low selectivity values at high productivity values in the selected part of the nitrate concentration. It was established that the ion exchange method is significantly more effective than reverse osmosis in removing nitrates from water. It ensures the reduction of nitrate content in purified water to a value of less than 1 mg/dm3 when the degree of their extraction is reached at the level of 99%. As the ionite is saturated with nitrates, the efficiency of their extraction decreases. Anionite sorbs nitrates effectively enough, being both in the chloride mixture and in the sulfate form. Nitrates are effectively desorbed by 2H solutions of sodium chloride and sodium or ammonium sulfate.
EN
The Carpathian region is distinguished by a high tourist flow and variety of hotels. The need for consumption of quality drinking water for tourists and local population is determined. Underground sources and wells constitute a water supply of accommodation facilities in this region. The issue of drinking water quality in the Carpathians remains poorly studied. It is necessary to realize the landscape, the content of heavy metals in the rocks, the differences in elevation, and tourist flow that can cause diffusion pollution. Sources of water supply in the tourist area of the Ukrainian Carpathians are the subject of the article. The sociological survey of the owners of local tourist accommodation facilities showed that 17.5% use surface sources, 48.8% use underground sources, 32.5% use mixed sources, 56.2% of respondents dispose of sewage disposal without proper water reclamation. We took samples of drinking water from sources, wells in this region and analyzed such indicators as pH, temperature, altitude, nitrates and nitrites, phosphates, ammonium, and mineralization. Sensafe’s visual membrane tests for drinking water determined heavy metals such as Cu, Ni, Co, Zn, Cd, Hg, Fe in the water samples. The functional dependence of the content of heavy metals and the altitude zonation of drinking water sources for the region іs described by the equation y = -0.059ln(x) + 0.4219.
EN
The purpose of this research was to determine the groundwater intrinsic vulnerability to pollution of shallow groundwater in Wielkopolska Province, Poland and to assess the risk of pollution by nitrates. Wielkopolska is known as an area where the problem of water pollution by nitrates has existed for a long time due to intensive agriculture. DRASTIC method and its optimized version as well as four other risk evaluation methods were selected to assess the risk pollution with nitrates. The results of either method did not correlate with nitrate concentrations recorded in the total of 1679 groundwater monitoring points. Therefore a new method of groundwater pollution risk assessment (NV-L) was proposed. The new method is based on optimized results of the DRASTIC system and the L parameter which considers not only land use types, but also the amount of nitrogen loading leached from soil as a result of fertilizer consumption, and from wet deposition. The final results of NV-L method showed that the largest part of the study area is covered by a very low class of pollution risk (30.6%). The high and very high classes occupy 11.6% of the area, mostly in the areas designated until 2012 as the Nitrate Vulnerable Zones. Validation of the results of all methods showed that the other methods than NV-L cannot be used as a basis for reliable assessment of the risk of groundwater pollution by nitrates, as they do not take into account the nitrogen load leached from the soil profile.
PL
Celem badań było określenie podatności wód podziemnych na zanieczyszczenie płytkich wód podziemnych w województwie wielkopolskim oraz ocena ryzyka zanieczyszczenia azotanami. Województwo wielkopolskie uważane jest za obszar, na którym od dawna znany jest problem zanieczyszczenia wód azotanami z powodu intensywnego rolnictwa. Do obliczenia indeksu podatności naturalnej wybrano metodę DRASTIC i jej zoptymalizowaną wersję, natomiast do oceny ryzyka zanieczyszczenia azotanami cztery metody będące modyfikacjami metody DRASTIC. Wynik żadnej z nich nie był skorelowany ze stężeniami azotanów odnotowanymi w 1679 punktach monitoringu wód podziemnych, dlatego zaproponowano nową metodę oceny zagrożenia wód podziemnych NV-L. Metoda opiera się na zoptymalizowanych wynikach systemu DRASTIC i parametrze L, który uwzględnia nie tylko typ użytkowania gruntów, ale także wielkość ładunku azotu, pochodzącego z wymywania z gleby nawozów mineralnych i organicznych oraz z mokrej depozycji w opadach. Wyniki metody NV-L wykazały, że największy obszar objęty jest bardzo niską klasą zagrożenia zanieczyszczeniami (30,6%). Klasa wysoka i bardzo wysoka zajmują 11,6% powierzchni, głównie na obszarach wyznaczanych do 2012 roku jako obszary szczególnie narażone na wymywanie azotu do wód powierzchniowych. Wyniki wskazują, że w procedurach zastosowanych metod oceny podatności brakowało pewnych ważnych informacji. Dlatego ich wyniki należy traktować jako szacunkowe i nie mogą one być wykorzystywane w dalszych analizach jako użyteczne narzędzie ochrony wód podziemnych. Uwzględnienie innych, nowych elementów do oceny podatności wód podziemnych lub ryzyka zanieczyszczenia, może okazać się kluczowym czynnikiem, jak miało to miejsce w przypadku metody NV-L i wykorzystania danych dotyczących ładunku azotu wymywanego z profilu glebowego.
EN
Plant nutrition is one of the significant factors determining the quantity and quality of crop production. Therefore, the objective of the experiment was to express the dependence numerically (statistically) of the selected yield parameters of radish on the contents of ammonium and nitrate nitrogen occurring in the soil growing medium in different periods of radish vegetation. The experiment was performed in the plastic greenhouse with aeration and irrigation manually operated. It had three variants and was established by the method of random plot arrangement with a threefold repetition of variants. The variants differed in the quantity of vermicompost in the soil growing medium (0%, 10%, 20%). The achieved results indicate that the yield parameters of radish were more dependent on the contents of N–NO3- than on the contents of N–NH4+ occurring in the soil substrate. The quantity of N–NO3-, occurring in the soil growing medium in the initial period of the growing season, had impact on the quantity of yield. The quantity of N–NO3-, present in the soil substrate in the second half of the growing season, had impact mainly on the content of vitamin C and content of nitrates in roots. As the N–NO3- content of the soil growing medium increased, the content of nitrates was increased and content of vitamin C was decreased. The dependence between the contents of N–NH4+ in the substrate and root yield was insignificant. The quantity of radish root yield depended predominantly on the contents of Nin occurring in the soil growing medium at the beginning of the growing season. On the contrary, the content of nitrates and vitamin C (influencing the yield quality) was dependent mostly on the contents of Nin present in the soil substrate in the second half of radish growing season. Along with the increase in the content of Nin, the root yield and the content of nitrates in roots also increased, while the content of vitamin C was decreased.
PL
Eutrofizacja jest jednym z głównych problemów Morza Bałtyckiego, do którego uchodzą rzeki z ponad 99% terytorium Polski. Analizy wskazują, że największym źródłem biogenów, odpowiedzialnym za ponad połowę wszystkich ładunków azotu i fosforu docierających do polskich wód powierzchniowych jest rolnictwo. Szczególnie ważne jest więc wdrażanie działań ograniczających zanieczyszczenie wód biogenami pochodzącymi ze źródeł rolniczych. Ramy prawne dla takich działań zapewnia dyrektywa 91/676/EWG, tzw. dyrektywa azotanowa. W artykule przedstawiono najważniejsze wnioski ze sprawozdania z realizacji dyrektywy azotanowej w Polsce w latach 2016–2020. Podjęto również próbę oceny skuteczności wprowadzonych działań. W Polsce w ostatnich latach nastąpiła znacząca zmiana w podejściu do wdrażania tej dyrektywy, polegająca na objęciu działaniami obowiązkowymi wszystkich podmiotów prowadzących produkcję rolną.
EN
Eutrophication is one of the main problems of the Baltic Sea, being the catchment basin of over 99% of the rivers flowing on the territory of Poland. Analyses indicate that the largest source of biogenes, responsible for over half of the entire nitrogen and phosphorus loads reaching Polish surface waters, is agriculture. It is therefore of key importance to implement actions reducing the water pollution with biogenes originating from agricultural sources. The legal framework for such actions is ensured by the 91/676/EEC Directive, the so called Nitrates Directive. The article presents major conclusions of the report on implementation of the Nitrates Directive in Poland in the years 2016–2020. It also attempts at evaluating the effectiveness of the implemented measures. Recently in Poland, an important change in the approach to implementation of this directive has occurred, consisting in covering all entities carrying out agricultural production with mandatory actions.
EN
A method to improve the quality of purified water, reduce the cost of reagents for the regeneration of resin and create low-waste processes have been developed. This paper presents the results of ion exchange separation of sulfates and nitrates using AV-17-8 anion exchange resin in NO3 form. The efficiency of anion separation on the highly basic anion exchange resin AV-17-8 depends on the magnitude and ratio of their concentrations in water. Separation on the AV-17-8 anion exchange resin has been shown to be effective at concentrations of sulfates up to 800 mg/dm3 and nitrates up to 100 mg/dm3. Conditions for regeneration of 10% NaNO3 anion exchange resin were determined. Reagent precipitation of sulfates from the used regeneration solution in the form of calcium sulfate was carried out. Calcium sulfate precipitate can be used in the manufacturing of building materials. The regeneration solution is suitable for reuse. The developed results will allow to introduce low-waste desalination technology of highly mineralized waters.
PL
Celem pracy było opracowano metody poprawy jakości oczyszczonej wody, obniżenia kosztów odczynników do regeneracji żywicy i stworzenia procesów niskoodpadowych. W pracy przedstawiono wyniki rozdziału jonowymiennego siarczanów i azotanów z użyciem żywicy anionowymiennej AB-17-8 w postaci NO3. Skuteczność separacji anionów na wysoce zasadowej żywicy anionowymiennej AB-17-8 zależy od wielkości i stosunku ich stężeń w wodzie. Wykazano, że rozdział na żywicy anionowymiennej AB-17-8 jest skuteczny przy stężeniach siarczanów do 800 mg/dm3 i azotanów do 100 mg/dm3. Określono warunki regeneracji 10% żywicy anionowymiennej NaNO3. Przeprowadzono odczynnikowe wytrącanie siarczanów z zużytego roztworu regeneracyjnego w postaci siarczanu wapnia. Osad siarczanu wapnia może być wykorzystany do produkcji materiałów budowlanych. Roztwór do regeneracji nadaje się do ponownego użycia. Opracowane wyniki pozwolą na wprowadzenie niskoodpadowej technologii odsalania wód wysokozmineralizowanych.
EN
The ground source of drinking water for the village of Skalice nad Svitavou is located 35 km North of Brno (Czech Republic). An evaluation of developments in selected indicators of water quality in this groundwater source in the period 2013–2017 was the essence of this work. The data was provided by Vodárenská akciová společnost, a.s., i.e. the operator. At the same time, annual monitoring of water quality in the Úmoří stream, which flows through the catchment area and can affect the quality of groundwater, was carried out. Water samples were collected in 2017–2018 from 6 profiles on the Úmoří stream and its two tributaries. Raw water from the groundwater source does not meet the requirements for drinking water in some indicators and needs to be treated. Monitoring of surface water shows that the most problematic indicator is total phosphorus, the concentration of which exceeded limit values on all sampling profiles. The highest values were found in the tributaries, where total phosphorus concentrations exceeded 10 mg∙dm–3. There are 12 municipalities in the area of interest, only two of which have their own sewage treatment plant. It is clear from the results that wastewater in some municipalities is discharged directly into the recipient and is the cause of above-limit concentrations of both phosphorus and nitrogen. Intensively used agricultural land is another major source of pollution. Based on an analysis of sources of pollution, corrective measures have been proposed to improve the quality of surface and groundwater in the area.
EN
The removal of nitrates from aqueous solutions is cumbersome because of their high solubility in water. The use of zero-valent iron (ZVI) for the reduction of nitrates is the chemical process and it is an alternative method to the biological ones. The aim of the present study was to evaluate the effectiveness of nitrates removal from water solution by using the ZVI process. The process was coupled with the removal of COD, phosphates and turbidity by using by-products of nitrates reduction. Batch tests were performed to evaluate the effectiveness of ZVI in the removal of nitrates from aqueous solutions. The effectiveness of nitrates removal was analyzed after 5, 10, 20, 30 and 60 min. and compared to the initial concentration of pollutants. Simultaneously analysis of ammonium nitrogen and nitrites was controlled to identify products of nitrates reduction under various pH. The removal of COD, phosphates and turbidity was also performed in batch tests. The effectiveness of the removal by using three types of chemicals was compared – PIX, FeSO4, and waste Fe2+/Fe3+ from the ZVI process. The results obtained in the study indicate that ZVI can be effectively used in the treatment of water polluted with nitrates and the by-products of the process could be further applied in the removal of COD, phosphates and turbidity. Based on the results the method should be advised as a promising alternative to the technologies used nowadays under technical scale as a technology that fits with a circular economy.
EN
New polymers with potential application in a waste water purification from inorganic contaminants were synthesized via a chemical modification of poly(vinyl chloride) by "click” method based on copper(I)-catalyzed Huisgen reaction. The structure of the resulting polymers containing 1,4-disubstituted triazole units was confirmed by infrared spectroscopy (ATR-FTIR), nitrogen elemental analysis and differential thermal analysis (DTA). The obtained polymers were subsequently used in the elimination of nitrate ions and metalions from the wastewater of Beja region (Tunisia). It was found that new polymers were most efficient in capturing of zinc ions, the average extraction percentage of Zn2+ was 28%, while the average extraction percentage of nitrates did not exceed 12.5%. The selectivity of the binding of investigated ions can be arranged in the following order: Zn2+> NO3–> Ca2+> Mg2+.
PL
W wyniku chemicznej modyfikacji poli(chlorku winylu) metodą „click”, opartej na reakcji Huisgena katalizowanej za pomocą miedzi, zsyntetyzowano nowe polimery o potencjalnym zastosowaniu do oczyszczania ścieków z zanieczyszczeń związkami nieorganicznymi. Nowe zsyntetyzowane polimery zawierają w swojej budowie jednostki 1,4-dwupodstawionego triazolu. Strukturę otrzymanych polimerów potwierdzono metodami spektroskopii w podczerwieni (ATR-FTIR), analizy elementarnej azotu i analizy termicznej (DTA). Polimery te wykorzystano następnie do eliminacji jonów azotanowych i jonów metali występujących w wodach ściekowych w regionie Beja (Tunezja). Stwierdzono, że nowe polimery najefektywniej wychwytują jony cynku (Zn), średni procent ekstrakcji (% E) wynosił 28 %, a średni procent ekstrakcji azotanów nie przekraczał 12,5 %. Selektywność wychwytu badanych jonów przez zsyntetyzowane polimery można uszeregować następująco: Zn2+ > NO3– > Ca2+ > Mg2+.
PL
Znowelizowana ustawa Prawo Wodne wraz z „Programem działań mającym na celu zmniejszenie zanieczyszczenia wód azotanami pochodzącymi ze źródeł rolniczych oraz zapobieganie dalszemu zanieczyszczeniu” została przyjęta w sierpniu 2018 r. Nowe przepisy całkowicie zmieniły sposób wdrażania dyrektywy azotanowej, uznając cały kraj jako jeden wielki obszary szczególnego narażenia (OSN). Dodatkowo wyznaczyły obszary „bieguna zimna” i „bieguna ciepła”, gdzie terminy nawożenia odpowiednio skrócono lub wydłużono. Nowe przepisy obowiązują zbyt krótko, żeby można było na podstawie danych monitoringowych odpowiedzieć na pytanie, czy są skuteczne i rzeczywiście spowodowały ograniczenie ładunku azotu wprowadzanego do wód powierzchniowych. W artykule przedstawiono możliwość wykorzystania makromodelu DNS/SWAT, jako narzędzia prognostycznego, na podstawie którego zbudowano trzy scenariusze wariantowe symulujące skutki ograniczenia lub wydłużenia okresów nawożenia w przykładowej zlewni Przymorza (rzeka Słupia, profil Charnowo). Otrzymane wyniki pozwoliły precyzyjnie określić zarówno wartości ładunku azotu ogólnego w wybranym profilu obliczeniowym, jak i przewidywany stopień jego zmniejszenia lub zwiększenia w zależności od przyjętej długości okresu nawożenia. Wyniki symulacji wykazały jednoznacznie, że bardziej restrykcyjne przepisy dotyczące okresów nawożenia wpłyną na zmniejszenie ładunku azotu w wodach powierzchniowych. Powstałe w ostatnim czasie narzędzia, takie jak Polski Atlas Natężeń Deszczów (PANDa), mogą znacząco poprawić weryfikację użytych modeli, w których moduł meteorologiczny odgrywa podstawową rolę, tak jak ma to miejsce w przypadku makromodelu DNS/SWAT przystosowanego do prowadzenia analiz jakości wód, ze szczególnym uwzględnieniem zabiegów agrotechnicznych prowadzonych w zlewni.
EN
The amended Water Law Act together with the “Program of measures aimed at reducing the pollution of waters with nitrates from agricultural sources and prevention of further pollution” was adopted in August 2018. The new regulations completely changed the implementation of the Nitrates Directive, recognizing the whole country as one large area of NVZ (nitrate vulnerable zone). In addition, “pole of cold” and “pole of heat” areas were designated where fertilization timelines were shortened or extended accordingly. It is too early to confirm the efficiency of the new regulations based on monitoring data or quantify their contribution to limiting nitrogen load in surface waters. Therefore, in this article, a DNS/SWAT macromodel was employed as a prognostic tool to develop three variant scenarios simulating the effects of limitation or extension of fertilization periods in the exemplary catchment of Przymorze (Slupia river, Charnowo profile). The results obtained allowed for a precise determination of both the total nitrogen load in the selected calculation profile and the anticipated degree of its reduction or increase depending on the assumed length of the fertilization period. The results indicate that more restrictive regulations regarding fertilization periods translate into a reduction in total nitrogen load in surface waters. Recently developed tools such as Polish Atlas of Rainfall Intensity (PANDa rainfall model) may significantly improve validation of the models employed. In these models, the meteorological module plays a central role like in the DNS/SWAT macromodel equipped to perform water quality analyses with a particular focus on agrotechnical measures implemented in the catchment.
PL
Fosfor jest podstawowym składnikiem białek i szkieletów kręgowców, uczestniczy w przemianach cukrów oraz tłuszczy. Organizm człowieka zawiera 1 kg fosforu, z czego 75% jego ilości znajduje się w kościach i zębach. Uczestniczy w procesach regulacji reakcji biochemicznych zachodzących w komórce (fosforylacji), pełni funkcję bufora utrzymującego stałe pH we krwi i w moczu. Fosfor jest związkiem biogennym, którego obecność w środowisku wodnym powoduje proces eutrofizacji przez wzrost fitoplanktonu, odtlenienie wody, wzrost mętności i zawartości siarkowodoru, prowadząc w konsekwencji do śmierci większych organizmów wodnych, na przykład ryb.
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