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Wyszukujesz frazę "Nutrient" wg kryterium: Temat


Tytuł:
Nutrient requirements of the premature infant and recommended nutrient intakes
Autorzy:
Anderson, G.H.
Zlotkin, S.H.
Powiązania:
https://bibliotekanauki.pl/articles/1372549.pdf
Data publikacji:
1996
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
nutrient intake
trace element
magnesium
premature infant
vitamin
water
carbohydrate
energy
nutrient requirement
feeding
fat
calcium
sodium
nutrient composition
potassium
protein
mineral intake
phosphorus
chloride
Opis:
In summary, the nutrient requirements of the premature infant are not well defined, but the CPS Nutrition Committee has provided a systemic framework for describing recommended nutrient intakes. These current recommended intakes appear to provide safe quantities of nutrients that support intrauterine growth rates. Still uncertain, however, is the extent to which the recommended intakes lead to the provision of energy and nutrients in quantity and composition in amounts that allow the premature infant to achieve all aspects of normal in utero development, especially that of the nervous system.
Źródło:
Polish Journal of Food and Nutrition Sciences; 1996, 05, 3; 3-12
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Soil phosphorus as plant nutrient and potential environmental pollutant
Autorzy:
Fuleky, G
Powiązania:
https://bibliotekanauki.pl/articles/806318.pdf
Data publikacji:
1993
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
Zala river
environment pollutant
maize monoculture
soil
plant nutrient
Hungary
phosphorus
Opis:
The usual range of P in soils is of the order of 500 to 800 mg kg⁻¹; in Hungarian soils it is 200-900 mg kg⁻¹ [3,9]. Total P is usually highest in the upper A horizon and lowest in the lower A and upper B horizons because of recycling by plants. The organic P content (10-60 % of total-P) is the highest in the top layer and decreases with depth in all soils [9].
Źródło:
Zeszyty Problemowe Postępów Nauk Rolniczych; 1993, 400
0084-5477
Pojawia się w:
Zeszyty Problemowe Postępów Nauk Rolniczych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling nitrogen and phosphorus limitation on phytoplankton growth in Narva Bay, South-Eastern Gulf of Finland
Autorzy:
Lessin, G.
Lips, I.
Raudsepp, U.
Powiązania:
https://bibliotekanauki.pl/articles/47604.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
nitrogen
Finland Gulf
numerical modelling
Narva Bay
nutrient limitation
phytoplankton
phosphorus
Opis:
The relative roles of nitrogen and phosphorus in the limitation of phytoplankton growth in Narva Bay, south-eastern Gulf of Finland, were studied by combining the results of numerical modelling and nutrient enrichment experiments.Mo delled biomass-based intracellular nutrient concentrations (nutrient functions) were used to estimate the limiting nutrient in Narva Bay.Nutr ient functions – NF ∈ [0; 1] for nitrogen and PF ∈ [0; 1] for phosphorus – define the dependence of the phytoplankton growth rate on nutrients: NF = PF = 1 corresponds to nonlimitation of phytoplankton growth by nutrients, whereas NF = 0 or PF = 0 to zero growth.T he biotests indicated the response of phytoplankton growth to an increase in nutrient concentration in the surrounding water.Thr ee locations were selected for detailed analyses of temporal variations in the nutrient functions: the offshore station N12, station N8 at the mouth of the River Narva, and coastal station 38.T he biotests were performed at the same stations. NF and PF reached values of 0.9 prior to the spring bloom. With the onset of the spring bloom, NF decreased rapidly and remained below 0.1 in the open part of Narva Bay for the rest of that period.I n the coastal zone, NF was in excess of 0. 1, with a local maximum in the river mouth area. PF decreased to 0.3–0.4 in the open bay after the spring bloom.I n the coastal zone PF remained above 0.4, with a certain increase from the midsummer minimum towards the end of summer.The numerical modelling results clearly show that nitrogen limits phytoplankton growth in Narva Bay.Ph osphorus limitation may occur only for a limited period and over a limited area at the Narva River mouth and other coastal locations.I n general, the biotests backed up the modelling results, the main exception being in the open bay during summer.The model does not account for nitrogen fixation, however.S ince N-fixing cyanobacteria were prevalent in the offshore area, the addition of phosphorus led to enhanced phytoplankton growth at station N12.
Źródło:
Oceanologia; 2007, 49, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diurnal variations in nitrogen, phosphorus and iron compounds in the Southern Baltic Sea
Autorzy:
Sikorowicz, G.
Falkowska, L.
Burska, D.
Dunajska, D.
Pryputniewicz, D.
Magulski, R.
Lewandowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/47649.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
iron
nutrient
Gdansk Deep
nitrogen
density stratification
diurnal variation
Baltic Sea
oxygen condition
phosphorus
Opis:
In order to assess their short-term variability, nutrient concentrations were measured at standard depths at 2 h intervals in the deepest region of the Gdańsk Deep during the first ten days of June 2001. The mean concentrations of nutrients in the euphotic zone were: NN (NO2 −, NO3 −, NH4 +) – 1.93 μmol dm−3, PO4 3− – 0.12 μmol dm−3 and Fetot – 0.11 μmol dm−3. During daylight hours, when the rate of assimilation was fastest, concentrations of nitrogen, phosphorus and iron compounds were very low. The phosphate concentration fell to a minimum (0.03 μmol dm−3) between 04:00 and 10:00 hrs, while total iron dropped to 0.01 μmol dm−3 between 10:00 and 16:00 hrs. Both levels were below the limiting values for phosphorus and iron. At night, concentrations of NO3 − and PO4 3− rose by 25%, those of NH4 + and Fetot by 35%. The mean molar ratios of NN:PO4 3− and Fetot:PO4 3− in the surface layer were subject to significant daily fluctuations. The molar NN:PO4 3− ratio was higher than the optimum value established for the Baltic Sea. Below the halocline, the concentrations of dissolved iron and phosphorus rose as a result of diffusion from sediments in response to changing redox conditions.
Źródło:
Oceanologia; 2005, 47, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deposition of organic matter and particulate nitrogen and phosphorus at the North Sea - Baltic Sea transition - a GIS study
Autorzy:
Jansen, D.L.
Lundqvist, D.P.
Christiansen, C.
Lund-Hansen, L.C.
Balstrom, T.
Leipe, T.
Powiązania:
https://bibliotekanauki.pl/articles/48457.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
organic matter
nutrient
deposition
nitrogen
Baltic Sea
sediment
phosphorus
North Sea
Geographic Information System
Opis:
A GIS (Geographical Information System) based study on deposition in the North Sea – Baltic Sea transition area has been carried out. The study is based on (i) a digital bathymetry model, (ii) 93 available 210Pb/137Cs sedimentation rate estimations, (iii) grain-size distributions, organic matter, C, N and P content of 64 top 1 cm sediment samples from the study area, and (iv) GIS-based modelling of resuspension potentials based on wind statistics. With the use of regression statistics on depth, resuspension potential and sediment characteristics, results are extrapolated area-wide from the 64 sampling positions. The area is divided into sediment types and classified as accumulation or erosion/transport bottoms. Model results show good agreement with existing maps of sediment distributions, indicating that the sediment distribution is governed to a large extent by windinduced waves. Correlations of sediment types, their deposition rates and their N and P contents were used to estimate spatial deposition rates. In all, the yearly deposition in the study area amounts to 2.8 million tons of organic matter, 0.14 million tons of total nitrogen, and 0.035 million tons of total phosphorus. Correlations of sediment types and dry bulk densities were used to infer spatial inventories of organic matter and total nitrogen and phosphorus in the top 1 cm of the sediments. A total of 100 million tons of organic matter, 4 million tons of total nitrogen, and 0.019 million tons of total phosphorus are contained in the top 1 cm of the sediments in the study area. In general, the deep parts of the study area with low resuspension potentials act as sinks for the fine-grained sediments and their associated particulate nutrients.
Źródło:
Oceanologia; 2003, 45, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal variability of water quality and nutrient removal efficiency of a restored wetland
Autorzy:
Vesselly, K.B.
Opio, A.
Mwanjalolo, M.
Kansiime, F.
Powiązania:
https://bibliotekanauki.pl/articles/2049699.pdf
Data publikacji:
2020
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
water quality
seasonal variability
nutrient
nitrogen
phosphorus
restoration
wetland
Uganda
wetlands
Restoration
phosphoru
Opis:
Most studies of wetlands in Uganda use for water and wastewater treatment have focused on natural undisturbed pristine wetland and constructed wetlands. There exists a gap in literature surrounding treatment abilities of restored wetland or wetlands on a path to recovery. Water quality parameters were sampled covering wet and dry seasons in a restored wetland. Soil properties were also assessed and compared with a referenced natural site. The objectives of the study were to (i) determine the effects of wetland restoration on nutrient retention and release, (ii) analyze temporal dynamics of water quality parameters in the restored wetland, and (iii) describe soil properties in depths of the restored wetland in relation to a reference natural site. Values of pH, electrical conductivity (EC), temperature, total dissolved solids (TDS), TN and NO3-N showed significant differences across seasons. The wetland demonstrated little water quality benefits but the overall nutrient removal efficiency when compared to literature values was found to be not impressive. Rates for P and N removal were between 3.5 - 19% and -10.8 – 32.4% respectively. These results could be attributed to flooding, low residence time of the water, small size of the wetland, low influent load, extra nutrient inputs from fertilizers and pollution sources as well as release from soil. We recommended that management activities like harvesting; redesigning the channels for water distribution throughout the system and removal of invasive plant species be carried out. This study will form a baseline in understanding the ecology of restored wetlands in Uganda.
Źródło:
Environment, Earth and Ecology; 2020, 4, 1; 50-61
2543-9774
2451-4225
Pojawia się w:
Environment, Earth and Ecology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Significance of nutrient fluxes via submarine groundwater discharge in the Bay of Puck, Southern Baltic Sea
Autorzy:
Szymczycha, B.
Klostowska, Z.
Lengier, M.
Dzierzbicka-Glowacka, L.
Powiązania:
https://bibliotekanauki.pl/articles/2079294.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
nutrient flux
nitrogen
phosphorus
submarine groundwater discharge
biogeochemistry
coastal zone
Puck Bay
Southern Baltic Sea
Opis:
In this study, we collected submarine groundwater discharge (SGD) and seawater samples at six sites in the Bay of Puck, in the southern Baltic Sea, in order to estimate the nutrient distribution in groundwater affected areas. In addition, we estimated nutrient fluxes via SGD, including both fresh SGD (FSGD) and recirculated seawater SGD (RSGD), to the entire Bay of Puck. Phosphate (PO43−) concentrations varied significantly among study sites and seasons, while both ammonium (NH4+) and nitrates (NO3−) concentrations varied only seasonally. The N:P ratio indicated P limitation in most of the samples. The estimated seasonal and annual loads, via SGD, of both dissolved inorganic nitrogen (DIN; 9303 t yr−1) and PO43− (950 t yr−1), were the most significant source of nutrients to the Bay of Puck, and notably higher than quantified before (FSGD nutrient loads of 50 t yr−1 and 56 t yr−1 for DIN and PO43−, respectively). The SGD fluxes reported here indicate some of the highest rates of sediment-water fluxes reported in the Baltic Sea. These results suggest that SGD (both FSGD and RSGD) should be considered as source of chemical substances to the marine environment.
Źródło:
Oceanologia; 2020, 62, 2; 117-125
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deposition, return flux, and burial rates of nitrogen and phosphorus in the sediments of two high-Arctic fjords
Autorzy:
Koziorowska, K.
Kulinski, K.
Pempkowiak, J.
Powiązania:
https://bibliotekanauki.pl/articles/48289.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
nitrogen
phosphorus
sediment
Hornsund region
Kongsfjorden
water column
pore water
nutrient concentration
Arctic fjord
Źródło:
Oceanologia; 2018, 60, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal changes of nutrients concentration in two shallow estuarine lakes gardno and Lebsko; Comparison
Sezonowe zmiany stężenia składników biogenicznych dwóch płytkich jezior przymorskich Gardna i Łebska; Porównanie
Autorzy:
Jarosiewicz, A.
Powiązania:
https://bibliotekanauki.pl/articles/85087.pdf
Data publikacji:
2009
Wydawca:
Akademia Pomorska w Słupsku
Tematy:
seasonal change
nutrient concentration
shallow lake
Lake Gardno
Lake Lebsko
comparison
phosphorus
nitrogen
eutrophication
aquatic ecosystem
Opis:
The aim of this paper was the presentation and comparison of seasonal biogens changes and trophy state classification of two biggest shallow coastal lakes Gardno and Łebsko, located in the northern part of Poland, along the southern coast of the Baltic Sea. Measurements were conducted once a month from April to December 2007. For the purpose of this article at each lake one measurement station was selected, to represent well mixed area of the lakes, far from outlet to the sea and rivers. Performed measurements showed that the lakes are similar. The differences, observed between biogens concentration in lakes were statistically insignificant. Seasonal dynamics of nutrients concentration in lakes indicated that the lakes are typical shallow lakes. Moreover, the summer concentration of total nitrogen and phosphorus qualify these lakes as eutrophic.
Celem niniejszego opracowania była prezentacja i porównanie sezonowych zmian stężenia substancji biogenicznych oraz określenie poziomu trofii dwóch jezior przymorskich Gardna i Łebska. Jeziora te zlokalizowane są wzdłuż południowego wybrzeża Morza Bałtyckiego. Zaprezentowane rezultaty są wynikiem badań prowadzonych od kwietnia do grudnia 2007 roku. Do celów publikacji na każdym z jezior wyselekcjonowane zostało jedno stanowisko pomiarowe, charakteryzujące się zarówno minimalnym oddziaływaniem słonych wód morskich, jak i słodkich wód rzecznych. Przeprowadzone analizy wykazały, iż dynamika składników biogenicznych w omawianych jeziorach jest podobna, a różnice stężenia poszczególnych form azotu i fosforu nie są istotne statystycznie. Ponadto zaobserwowano, że sezonowe zmiany stężenia biogenów w Gardnie i Łebsku mają przebieg typowy dla jezior płytkich. Określenie poziomu trofii jezior opierało się na porównaniu letnich stężeń azotu i fosforu całkowitego w toni wodnej jezior. Na podstawie tych porównań zarówno Łebsko, jak i Gardno zakwalifikowano do typu eutroficznego.
Źródło:
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline; 2009, 13 part I
1643-0115
Pojawia się w:
Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of sustainable nutrient management practices based on land degradation and rainfall effects on soybean yield and organic carbon and available N content in rainfed vertisols
Autorzy:
Sharma, R.A.
Raghu, J.S.
Powiązania:
https://bibliotekanauki.pl/articles/9195901.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Tematy:
sustainable practice
nutrient management
land degradation
rainfall effect
soybean
yield
organic carbon
nitrogen content
phosphorus
soil
Vertisol
Źródło:
Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura; 2003, 58; 205-221
0365-1118
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska. Sectio E. Agricultura
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of laser- and hydropriming of seeds on some physiological parameters in sugar beet
Autorzy:
Sacala, E.
Demczuk, A.
Grzys, E.
Prosba-Bialczyk, U.
Szajsner, H.
Powiązania:
https://bibliotekanauki.pl/articles/15329.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
laser stimulation
priming
seed
physiological parameter
sugar-beet
phosphorus
acid phosphatase
chlorophyll
carotenoid
sugar
nutrient value
Opis:
The aim of this study was to evaluate the effect of pre-sowing seeds treatments on some agro-physiological parameters of sugar beets. The selected seeds treatments were: laser stimulation, hydropriming and combination of hydropriming and laser radiation. The impact of the seeds stimulation was analysed by determining the acid phosphatase activity, concentration of phosphate and photosynthetic pigments in leaves as well as nutrient status and some yield parameters of the roots. The plants were assayed four times during vegetation period. Experiment shown that different priming methods had relatively small effect on both the level of orthophosphate and total phosphorus concentration. On the other hand, the plants raised from seeds both hydro- and laser-primed remained more stable level of phosphate during whole vegetative season than remaining plants. The highest activity of acid phosphatase was observed in the younger plants and amongst different seed treatments, plants grown from non-primed seeds and laser primed seeds showed the highest enzyme activity. In the later stages of growth the activity considerably lowered. Considering the effect of different seeds treatments it was observed a significant increase in enzyme activity in plants emerged from the hydroprimed or laser stimulated seeds as well as an increment of chlorophylls in plants emerged from the hydroprimed seeds and both hydro- and laser primed ones. Seeds stimulation had a positive effect on the potassium content particularly in leaves of sugar beet and on some yield parameters of the roots. Concluding, it can be stated that the effect of pre-sowing seed stimulation (priming) was visible during the entire growing season and amongst the examined methods of seeds treatment, hydropriming sole or in a combination with laser radiation caused the highest alterations in assayed parameters.
Źródło:
Journal of Elementology; 2016, 21, 2
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of selenium on selected macronutrients in maize plants
Wplyw selenu na zawartosc wybranych makroelementow w roslinach kukurydzy
Autorzy:
Hawrylak-Nowak, B
Powiązania:
https://bibliotekanauki.pl/articles/14287.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
maize plant
selenium
macronutrient
chemical composition
plant biomass
selenium concentration
nutrient solution
mineral balance
shoot tissue
calcium
phosphorus
Opis:
Selenium is an essential element for humans, animals and some species of microorganisms. In higher plants, however, the role of selenium is still unclear. Because selenium enrichment may influence the nutrient balance of plants, a study was done to test the effects of selenite-Se (Na2SeO3⋅5H2O) on selected macronutrients content in maize (Zea mays L. var. saccharata Kcke. cv. Złota Karłowa) seedlings. Plants were grown in Hoagland I nutrient solution (pH 6,2) amended with selenite at 0 (control), 5, 25, 50 and 100 μmol⋅dm-3 for 14 days. The dry weight of the shoots was then analyzed for phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) content. Phosphorus and calcium content increased, while potassium content decreased with increasing selenium treatments. No significant differences were found for magnesium level. Plant growth was affected by excessive selenium concentration. At low concentration (5 μmol⋅dm-3), selenium tended to stimulate the plant growth and the root elongation but at higher concentrations (50 and 100 μmol⋅dm-3) the dry mass accumulation and root tolerance index severely decreased. The study revealed that disturbances of growth and reduction of plant’s biomass at the presence of high selenium concentrations in the nutrient solution may have resulted from the disturbance of mineral balance of plants, namely accumulation of large amounts of calcium and phosphorus in shoot tissues.
Selen jest pierwiastkiem niezbędnym dla ludzi, zwierząt oraz niektórych mikroorganizmów, jednak jego rola w roślinach wyższych nie jest w pełni poznana. Ponieważ wzbogacenie podłoża w selen może wpływać na równowagę mineralną roślin, przeprowadzono badania dotyczące wpływu selenu w formie seleninu (Na2SeO3·5H2O) na zawartość wybranych makroelementów w siewkach kukurydzy (Zea mays L. var. saccharata Kcke. cv. Złota Karłowa). Rośliny rosły przez 14 dni w pożywce Hoaglanda I (pH 6,2) wzbogaconej w selen, który stosowano w następujących stężeniach: 0 (kontrola), 5, 25, 50 i 100 µmol·dm-3. Po tym czasie w suchej masie organów nadziemnych analizowano zawartość fosforu (P), magnezu (Mg), potasu (K) i wapnia (Ca). Stwierdzono, że wraz ze wzrostem stężenia selenu w pożywce, w organach nadziemnych roślin wzrastała zawartość fosforu i wapnia, malała zaś zawartość potasu. Nie wykazano istotnych różnic w zawartości magnezu. Wprowadzenie do podłoża selenu wpływało również na wzrost roślin. Stwierdzono, że selen w niskim stężeniu (5 µmol·dm-3) stymulował wzrost siewek oraz elongację systemu korzeniowego, ale w jego wyższych stężeniach tego pierwiastka (50 i 100 µmol·dm-3) akumulacja biomasy oraz indeks tolerancji korzenia drastycznie malały. Z przeprowadzonych badań wynika, że zaburzenia wzrostu oraz redukcja biomasy roślin w obecności wysokich stężeń selenu w podłożu może być związana z zakłóceniem równowagi mineralnej roślin, a zwłaszcza z gromadzeniem w tkankach pędów znacznej ilości wapnia i fosforu.
Źródło:
Journal of Elementology; 2008, 13, 4; 513-519
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rola krzemu w procesie eutrofizacji wód na przykładzie zbiorników Solina i Myczkowce
The Role of Silicon in the Process of Eutrophication of the Waters – Solina and Myczkowce Reservoirs Case Study
Autorzy:
Koszelnik, P.
Powiązania:
https://bibliotekanauki.pl/articles/1819150.pdf
Data publikacji:
2013
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
proces eutrofizacji wód
rola krzemu
nutrient limitation
dissolved silicate
retention
nitrogen
phosphorus
lake
transport
sediments
complex
river
Opis:
This paper reports on studies conducted during 2005–2006 years in the ecosystem of the Solina-Myczkowce mountain complex of mesotrophic reservoirs on the San River, SE Poland. The goal of the present study has been to analyse the functioning of the reservoirs as a dissolved silicon sink especially whether silicon assumes a limiting role where the biological productivity of reservoirs waters is concerned. Silicon is one of the biosphere’s most abundant elements, and one that – in the form of dissolved silica – serves as a very important nutrient playing a major role in the functioning of marine, coastal and inland waters. Investigations indicate that reservoirs are major sinks for the dissolved silica in a river system and that unfavorable changes in water chemistry downstream may ensue where (as is usually the case), the water discharged from a reservoir is poorer in Si than that supplied to it. The noted Si depletion in both the analysed reservoirs influenced growth of non-siliceous algae expressed in terms of chl a. Siliceous algal growth is usually observed there during spring. I suppose that the first chl a maximum in the case of the Solina Reservoir, and the only maximum in the Myczkowce Reservoir, result from the growth of both siliceous and green algae. The next increase in chl a – observed only in the Solina Reservoir – may result from the presence of the cyanobacteria often observed in warm lakes at the end of summer. Their absence from Myczkowce reflects the low temperature of that reservoir’s water, this being supplied from the hypolimnion of the upper one. These observations are confirmed in relationships between mean measured concentrations of Si and mean concentrations of chl a in the euphotic zone of the two reservoirs. Observed summer depletion of the silicate accelerates the growth of phytoplankton exponentially, especially in the case of the upper reservoir.
Źródło:
Rocznik Ochrona Środowiska; 2013, Tom 15, cz. 3; 2218-2231
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nutrient output from rural areas on the example of two catchments Skuterud and Zagozdzonka
Koncentracja biogenów w rolniczych zlewniach na przykładzie zlewni rzeki Skuterud i Zagożdżonki
Autorzy:
Sawa, K.
Hejduk, L.
Deelstra, J.
Oygarden, L.
Powiązania:
https://bibliotekanauki.pl/articles/81673.pdf
Data publikacji:
2011
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
nutrient output
rural area
river catchment
Skuterud River
Zagozdzonka River
rural catchment
agriculture
nitrogen
phosphorus
measurement method
monitoring programme
Opis:
In this paper, two rural catchment- the Zagożdżonka catchment in Poland and the Skuterud catchment in Aas, Akershus county in Norway are compared. In addition to the general description, more in particular information, runoff, NO3 load, P-PO4 load, total phosphorus and total nitrogen concentrations in streams are compared. The data compared are from 1993 to 1995 in Zagożdżonka catchment and from 1994- 1996 from Skuterud catchment. The average concentration of N-NO3 in Zagożdżonka River in the period was 0.85 mg•1-1 and the mean concentration of P-PO4 was 0.13 mg•l-1. In the stream in Skuterud catchment the average concentration of N-NO3 was 4.95 mg•1-1 and the mean concentration of P-PO4 was 0.04 mg•l-1. For both catchments the same data were also compared for the 2008. In Skuterud catchment the highest concentration of nutrients occurred in November, March and April, which was connected to the higher runoff from agricultural areas during the snowmelt period. In Zagożdżonka catchment the highest concentration of nutrients was noted in March, April and in summer time, which was connected to periods with high amounts of precipitation. Comparison of the two rural catchments showed many differences in applied measurement methods for water sampling, water measurement, discharge measurement, runoff amounts and management practices, which had an effect on results of monitoring program. The compared data can be useful to predict the development of future environmental conditions for example water quality. It can also be useful for predict how nutrient runoff will be in future. What is more the different conditions for runoff in Skuterud and Zagożdżonka then different measures are needed.
W artykule zostały porównane dwie rolnicze zlewnie, jedna zlokalizowana w Polsce- Zagożdżonka, druga w Norwegii- Skuterud. Poza ogólnymi opisami zlewni, porównywane informacje dotyczyły szczegółowych danych o opadach, spływie powierzchniowym, oraz stężeniach N-NO3, P-PO4, TP i TN w płynących wodach powierzchniowych. Dane ze zlewni Zagożdżonka pochodzą z lat 1993-1995, ze zlewni Skuterud z lat 1994-1996. Średnie stężenie N-NO3 w w badanym okresie w rzece Zagożdżonka wynosiło 0,85 mg•l, zaś średnie stężenie P-PO4 było równe 0,13 mg•l. W ciekach zlewni Skuterud średnia koncentracja N-NO3 wynosiła 4,95 mg•l, zas P-PO4 oscylowała około 0,04 mg•l. W obydwu przypadkach te same analizy były przeprowadzone i porównane dla roku 2008. Wyniki pokazały, że dla cieków zlokalizowanych w Skuterud najwyższa koncentracja nutrientów wystąpiła w listopadzie, marcu i kwietniu. Zaistniała sytuacja ma związek z wysokim spływem powierzchniowym z terenów rolnych podczas upraw ziemi oraz z okresami roztopów. W zlewni Zagożdżonki najwyższe stężenie nutrientów w rzece odnotowano w marcu, kwietniu oraz w okresie letnim, co miało związek z dużymi opadami w tym okresie. Porównanie dwóch rolniczych zlewni pokazało wiele różnic, miedzy innymi w stosowanych metodach pomiarowych, systemie monitoringowym i otrzymanych wynikach. Mimo wielu różnic przeprowadzona analiza może być przydatna w prognozowaniu przyszłych zmian warunków środowiskowych.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2011, 43, 1
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nodularia spumigena blooms and the occurrence of hepatotoxin in the Gulf of Gdańsk
Autorzy:
Mazur, H.
Plinski, M.
Powiązania:
https://bibliotekanauki.pl/articles/48762.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
nutrient concentration
Cyanoprokaryota
water temperature
nitrogen
Nodularia spumigena
hepatotoxin
Baltic Sea
occurrence
bloom
Gdansk Gulf
phosphorus
toxin
light intensity
Opis:
Nodularia spumigena forms extensive summer blooms in the Baltic Sea. The occurrence of the blooms is determined by water temperature, light intensity and nutrient concentration; levels of nitrogen and phosphorus in particular are critical. The time of the seasonal maximum and intensity of the Nodularia bloom in the Gulf of Gdańsk vary significantly from year to year. In 2001 a rapid and massive proliferation of N. spumigena was observed in late June – early July. The concentration of nodularin in water ranged from 90 to 18 135 μg dm−3 and in lyophilised phytoplankton samples from 3000 to 3520 μg g−1 d.w. (dry weight). Such a high concentration of toxin in the recreational waters of the Gulf of Gdańsk constitutes a health risk for users of bathing areas. In 2002, the N. spumigena bloom was less dense, but lasted longer, with a maximum in late July – early August. In 2002 the concentration of nodularin did not exceed 12.6 μg dm−3 in water and 919 μg g−1 d.w. in lyophilised phytoplankton samples. Other cyanobacterial toxins – microcystins and anatoxin-a – were also detected in the coastal waters of the Gulf of Gdańsk.
Źródło:
Oceanologia; 2003, 45, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł

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