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EN
The present study of factors which affect the load of water ecosystems with mineral nitrogen compounds (N-NH_4 and N-NO_3) was conducted in the Olsztyn Lake District and covered the time period from 1992 to 1999. Three capture basins were investigated: agricultural drained with a drain network, agricultural drained with a drainage ditch, and agricultural-forested drained with scattered drains and ditches. It was found that the concentration and load of mineral forms of nitrogen in waters running off from rural areas were closely dependent on meteorological conditions, the kind of artificial drainage system in use, and the type of land use in the catchment area. In waters carried away through the drainage systems, average annual concentrations of N-NH4 ranged from 0.16 mg dm^-3 (the agricultural capture basin drained with ditches) to 1.09 mg dm^-3 (the agricultural catchment drained with a network of drains); the amounts of N-NO_3 ranged from 0.29 mg dm^-3 (the agricultural-forested catchment) to 8.06 mg dm-3 (the agricultural catchment drained with a network of drains). It was also observed that a larger share of arable lands in the land use structure in a given catchment caused an increase in the load of N-NO_3 determined in drained waters. In addition, it was confirmed that the amounts of mineral nitrogen carried away with drained waters annually varied from 12.78 kg N (6.7 kg N on average) per 1 ha of an agriculturally used catchment, of which N-NO_3 was a dominant form (12.23 kg).
EN
The Oder River creates one of the largest estuaries in Poland. The estuary can be divided into three zones, each with a different hydrochemical regime: the Pomeranian Bay (salt water habitat), the Szczecin Lagoon (brackish water habitat), the Oder River up to the Widuchowa section (transitional environment – brackish and typical freshwater). The Pomeranian Bay was characterized by the lowest concentration of nutrients throughout the research series in comparison to the other regions. It had a low nitrogen to phosphorus proportion and the highest stability of variability in total nitrogen concentration. The Szczecin Lagoon was characterized by a higher concentration of nutrient loads in comparison to the Pomeranian Bay, by a lower nitrogen and phosphorus proportion than the Oder waters, and by the high stability of variability of concentrations of mineral nitrogen and total nitrogen. As the "nutrient trap" for the Oder estuarine system, the Oder River, with its highest nutrient concentration, is characterized by the highest stability of variability of total nitrogen concentration.
EN
With the International Energy Agency (IEA) projecting that the global demand for natural gas to increase by 50% from 2010 to 2035, the exploration of unconventional gas reserves (e.g. shale gas, tight gas and coal bed methane) will gain increasing importance as conventional gas reserves become more depleted. To enhance the production of unconventional gas and oil, water-based fracturing fluids are extensively used for the stimulation of North American shale plays because they are inexpensive and offer excellent proppant transport into the fracture when used with gelled polymers. However, in circumstances where water-based fracturing fluids are unsuitable due to concerns related to water sensitivity and clay swelling, alternative fracturing fluids are used such as nitrogen and carbon dioxide treatments. Nitrogen and carbon dioxide fracturing fluids are particularly advantageous in depleted and shallow formations because they offer a non-damaging effect around the fracture, rapid cleanup of flowback fluid, and reduced water requirements compared to conventional water-based fracturing fluids. Much research has been published about water-based fracture treatments, therefore, this review paper considers the use of nitrogen and carbon dioxide fracturing fluids used for the stimulation of unconventional shale plays, mainly in North America. By analysing selected literatures studies, this review paper summarises the utilization of the various types of nitrogen and carbon dioxide treatments (i.e. straight gas, foam, energized, cryogenic liquids) across various shale plays such as the Montney play, the Devonian play, and the Marcellus play. The paper further identifies the major benefits and challenges of nitrogen and carbon dioxide treatments documented by well operators, which will facilitate knowledge transfer about the applicability of nitrogen and carbon dioxide fracturing fluids.
EN
The purpose of the study was to determine seasonal changes of ammonia nitrogen, nitrate nitrogen, total nitrogen, phosphate and total phosphorus in the years 2003–2009 in the river Supraśl. For this purpose a monitoring network was created with selected three control points on the basis of which the assessment was made. Control points were located near Gródek, Nowodworce and Dzikie. The research results were averaged for each month. On this basis the assessment of seasonal changes of nitrogen and phosphorus forms in the river Supraśl has been carried out. Research and analysis showed that the concentration of nitrogen and phosphorus in waters of Supraśl were characterized by a clear seasonal variation, the highest concentration of nitrogen was observed in January and February and the lowest in June in each of the analyzed points, the course of changes in the concentration of nitric and total nitrogen in March were different from the general course of reigning changes in their concentrations in surface waters.
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A buffer zone is a belt of shelter or permanent grassland separating the agricultural land from watercourses and water reservoirs. According to the Code of Good Agricultural Practices, they constitute a landscape element that can limit the migration of biogenic substances. Increasing attention is paid to the fact that these barriers are effective during the growing season. However, in the autumn-winter and early-spring half-year, they can be a source of nitrogen compounds leached from the catchment to the surface water. In connection with this, research was undertaken to assess the content of nitrogen compounds in the soil of the zone at the channel and water of the watercourse in a small agricultural catchment. The processes occurring in the buffer zones leading to the release of biogenic compounds do not only concern leaching them to surface and groundwater; therefore, the amount of nitrous oxide emissions, which is the result of the denitrification process occurring in the soil, was examined. On the basis of the obtained results, it was found that an increased content of nitrogen compounds in the soil of buffer zones may have an impact on the elevated emission of N2O and a raised content of these substances in surface water.
EN
Plant growth-promoting rhizobacteria (PGPR) isolated from the rhizosphere soil of eight field crops at different locations in Egypt were identified. Rhizobacteria strains were identified as Bacillus endophyticus AW1 5, B. filamentosus EM9, ET3, Micrococcus luteus KT2, FW9, FC13, SaW4, Enterobacter cloacae SK18, Pseudomonas azotoformans TPo10, Citrobacter braakii TC3. All isolates solubilised insoluble phosphate and produced IAA, while only six were able to produce siderophores in vitro. Vegetative growth and yield of wheat cv. ‘Sakha 94’ were enhanced after the application of single inoculation of each isolate compared to the control. Grain yield was increased by 20.7-96.5% over the control according to bacterial isolates. Available phosphorus (P) and counts of total bacteria in soil were observed to be significantly increased in treatments than in control. After the wheat harvest, soil pH was observed to be decreased, and a highly significant negative correlation was observed between soil pH and the levels of available phosphorus. Significant increases in grain and straw yields, as well as uptake of nitrogen (N) and P by plants, were observed due to inoculation with PGPR isolates. Levels of photosynthetic pigments, free amino acids, free phenolics, and reducing sugars in flag leaf and spikes were significantly enhanced by the application of all PGPR isolates compared to the control. Thus this study identifies the PGPR isolates for the improvement of the growth, yield, and quality of wheat. The study may be also useful for field evaluation under different soils and environmental conditions before generalising PGPR isolates as biofertilisers.
PL
Podjęto próbę odpowiedzi na pytanie, jak wpływa skład chemiczny atmosfery spiekania na strukturę i własności mechaniczne spiekanych konstrukcyjnych stali manganowych o składzie Fe-3%Mn-0,6%C. Dotychczas uważano, że aby uzyskać wysokie własności wytrzymałościowe spiekanych stali manganowych, proces spiekania musi być prowadzony w atmosferze bogatej w wodór. Obniżenie zawartości wodoru w atmosferze spiekania, w połączeniu z utrzymaniem wysokich własności mechanicznych stali, może korzystnie wpłynąć na ekonomię procesu wytwarzania stali manganowych, co z kolei wykaże znaczenie manganu jako dodatku stopowego zastępującego dotychczasowo stosowane chrom, nikiel, molibden i miedź.
EN
An attempt was made to answer the question, how chemical composition of a sintering atmosphere influences the structure and mechanical properties of the sintered constructional manganese steel of the composition Fe-3%Mn-0,6%C. It was believed so far that, in order to get high mechanical properties of the sintered manganese steels, the sintering process should be conducted in a hydrogen-rich atmosphere. However, decrease of hydrogen content in a sintering atmosphere combined with maintaining high mechanical properties of the steel produced may have a beneficial effect on the costs of manganese steel fabrication process, which in turn indicates the benefits of using manganese as an alloy additive instead of chromium, nickel, molybdenum and copper, which are used at present.
EN
This paper presents the results of studies which aim was to determine the pollution of the water environment for both methods of preparation for the utilization of sewage sludge in agriculture. The study was conducted in 2008-2012 in lysimeters filled with light sandy soil (clayey sand). During the study variants with equal doses of nitrogen in an amount of 20 g . m-2 (15.7 g per one lysimeter) were supplied to the soil in sewage sludge and in the compost made from the same sludge. These variants were used three times for two species of perennial plants: Miscanthus gigantenus i Sida hermaphrodita Rusby. In a variant of sludge soil fertilizing, it was leached into water environment more than 12% of the applied nitrogen over 5 years of research. In case of compost nitrogen leaching was reduced to 8.1-10.0% of the quantity supplied to the soil.
EN
The aim of the study was to evaluate the changes in the carbon/nitrogen ratio as a result of different natural methods of sewage sludge treatment from two municipal wastewater treatment plants. The sludge from the first treatment plant was poured into two lagoons, one covered with reed and the other with willow and a field with Californian earthworms. The sludge from the second treatment plant was composted with sawdust. The sludge processed with each method was simultaneously subjected to Effective Microorganisms. The samples of processed sludge from both treatment plants were collected three times. In the first one, after five weeks, four months and ten months from the beginning of treatment. The material from the second treatment plant was composted after four, ten weeks and a year of composting. In the samples taken, the total nitrogen content was determined by means of the Kjeldahl method. The determination of the organic carbon content was carried out on a TOC analyser. The C:N ratio was then calculated. It was found that the changes in the C:N ratio depended on the duration of individual processes, and to a lesser extent on the way they were processed. The carbon content during sludge processing increased or remained at a similar level and the nitrogen content decreased with time of their processing, regardless of the EM addition. The addition of Effective Microorganisms to the sludge treatment reduced the C:N ratio in the first period of time and increased this ratio to the optimal value after 10 months or a year. The best technology for sludge processing appeared to be the technology of heap composting with sawdust and with aeration. The ten-week compost had a suitable C/N ratio for use in lawn production.
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Content available remote May a cormorant colony be a source of coliform and chemical pollution in a lake?
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EN
Studies on the influence of a perennial cormorant colony on chemical and microbial pollution of a reservoir were conducted in Chrzypskie Lake. During the investigation carried out between 2009-2010 in the area of the colony, 155-175 breeding pairs were observed. High pollution of groundwater with biogenic elements and coliform bacteria (together with E. coli) was recorded within the boundaries of the colony. Pollutants migrated to the lake together with groundwater. Mean values of the analyzed forms of biogenic elements and bacteria formed a gradient from the highest values recorded near the colony to the lowest ones recorded in the central part of the lake.
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EN
Erosion strongly influences the soil properties and affects the intra-field variation of nutrients not only in steep young morainic landscapes but also on gentle slopes of old-glacial landscapes. The aim of the study was the evaluation of changes in the plant-available nutrient contents in the complex old-glacial eroded landscape of the Bielska Plain in the north-eastern part of Poland. The soil samples were collected from the soil profiles located along the transect beginning on the flat summit of the kame hummock extending through south-facing convex slope, the toeslope and footslope and further through the north-facing uniform slope. The content of plant-available forms of phosphorus (Pdl) and potassium (Kdl) and mineral forms of nitrogen (NH4-N and NO3-N) were determined in every soil profile. The soils located in various landscape positions were characterized with different fertility. In the soil located on the toeslope the content of NO3-N, Pdl and Kdl was high, while the soil located on the summit was rich in NH4-N and poor in the plant-available forms of K and P. The erosional distribution of plant-available N, P and K enhances the variation of nutrient content within one field and contributes to high variability of crops.
EN
The results of hydrochemical tests of the Gwdy river in the area of the town of Piła are presented in this study. The catchment area of the Gwda river comprises the area of 4942.8 km2. The surface of catchment area is covered with forest in 43.1%, arable land constitutes 36.5%, and grassland 7.2%. The Gwda river is a right-bank tributary of the Noteć River of IV order. Water samplings were collected in 2009 from three measurement and control points located between 13 and 24 kilometre of the course of the river. During the tests thermal and oxygen conditions were marked and biogenic substances (nitrate acid, ammonia nitrogen, nitrite nitrogen, total nitrogen, total phosphorus and mineral phosphorus). Concentrations of most of the indicators examined qualified the waters of Gwda to the waters of good quality. The indicator whose concentrations exceeded the limit values for the waters of quality was general phosphorus.
EN
Although the phenomenon of compensatory growth has been documented in some animals and higher plants, little information is available on its manifestation in marine microalgae. We have conducted the first study on the compensatory growth of the red tide causative dinoflagellate Prorocentrum donghaiense after its recovery from different nitrogen concentrations. The results showed that NaNO3 concentrations of 0 and 7.5 mg l-1 significantly reduced the growth of P. donghaiense, as compared to 37.5 and 75 mg l-1. When the microalgal cells were returned to 75 mg l-1, they exhibited subsequent compensatory growth. The most significant compensatory growth was found in those cells previously experiencing 0 mg dm3, followed by 7.5 mg dm3, indicating that compensatory growth depended on the extent of nitrogen stress they had been subjected to. Our results suggest that compensatory growth can be induced in the marine microalga P. donghaiense after its recovery from nitrogen fluctuation, and that this should be taken into consideration in the prevalence of P. donghaiense blooms in coastal waters.
EN
The objective of the study was to trace the variability of the hydrochemical conditions in three lakes of the West Pomeranian Voivodeship (Poland) - Starzyca, Maszewskie and Nowogardzkie in the annual cycle. The research was done in 2018-2019, and samples for analysis were collected 4 times a year. All analyses were performed applying standard methods. Such hydrochemical indices were determined as dissolved oxygen, chemical oxygen demand, content of orthophosphates, total phosphorus, nitrite, nitrate, ammonium, chlorophyll a and iron. The study showed that all lakes in the research cycle were characterised by a polymictic type of water mixing, and the trophic level, based on the adopted criteria, indicated advanced eutrophy, which may also be caused by anthropogenic pressure. Oxygen conditions characterised by deoxidation of the waters in the bottom layer in the spring and summer seasons, and clear oxygenation in the surface water layer (in Lake Maszewskie reaching even 188.5% in the spring) confirm the significant advancement of the eutrophication process. The supply of phosphorus and nitrogen in spring from pelagic waters in the waters of the examined lakes influences concentrations of chlorophyll a in the summer. The influence of “internal supply” (bottom waters and bottom sediments) on the amount of nutrients available for autotrophs is clearly visible in the analysed lakes - an increase in nitrogen and mineral phosphorus concentrations in relation to surface waters was observed in the bottom layer.
PL
Charakterystyka wód nadosadowych. Gospodarowanie wodami nadosadowymi pochodzącymi z odwadniania osadów Efektywność procesów oczyszczania wód nadosadowych Metody fizyczno-chemiczne i biologiczne.
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