Organic matter effects on phosphorus sorption in sandy soils     

Magdalena Debicka  Andrzej Kocowicz  Jerzy Weber  Elżbieta Jamroz 《Archives of Agronomy and Soil Science》2016,62(6):840-855

Phosphorus (P) sorption processes in soils contribute to important problems in agriculture: a deficiency of this plant nutrient and eutrophication in aquatic systems. Soil organic matter (SOM) plays a major role in sorption processes, but its influence on P sorption remains unclear and needs to be elucidated to improve the ability to effectively manage soil P. The aim of this research was to investigate the influence of SOM on P sorption. The study was conducted in sandy soil profiles and in topsoils before and after removal of SOM with H₂O₂. The results were interpreted with the Langmuir and Freundlich isotherms. Our results indicated that SOM affected P sorption in sandy soils, but that P sorption also depended on specific soil properties (e.g. values of the degree of P saturation (DPS), P sorption capacity (PSC) and pH) often related to land use. Removal of SOM decreased PSC in most of the topsoils tested; other soil properties became important in controlling P sorption. An increase in P desorption observed after SOM removal indicated that SOM was potentially that soil constituent which increased P binding and limited P leaching from these sandy soils.  相似文献   

Identification and differences of total proteins and their soluble fractions in some pseudocereals based on electrophoretic patterns     

Drzewiecki J  Delgado-Licon E  Haruenkit R  Pawelzik E  Martin-Belloso O  Park YS  Jung ST  Trakhtenberg S  Gorinstein S 《Journal of agricultural and food chemistry》2003,51(26):7798-7804

Genetic diversity and relationships of 11 species and cultivars belonging to different Angiosperms families were examined using sodium dodecyl sulfate seed protein markers. The protein was resolved into 36 bands (for soybean), 41 (for quinoa), 35 (for buckwheat), and 28 to 39 bands of Amaranth species, respectively. All species and cultivars can be distinguished from each other. Soybean, quinoa, and buckwheat species had a characteristic protein pattern showing a high degree of polymorphism. The protein patterns of soybean were considerably different from other species. Amaranth species had similar seed protein electrophoretic profile. The similarity coefficients calculated on the basis of presence and absence of bands ranged from 0.08 to 0.97. Following the UPGMA algorithm of similarity coefficients, the examined species and varieties could be clustered into two similarity groups. Our results did not confirm the Tachtadzjan hypothesis that Polygonales (e.g., buckwheat) and Caryophyllales (e.g., quinoa and amaranth) are closely related. Our data rather indicate occurrence of significant genetic distance (similarity coefficients 0.05-0.10). Also, it is doubtful that amaranth and quinoa species are also closely related (similarity coefficients varied from 0.16 to 0.25). It seems that soybean, quinoa, buckwheat, and amaranth (as a genus) can be considered as phylogenetic distant taxa. Differences and similarities in the secondary structure were observed by circular dichroism spectra. Some similarity was found between these plants in their soluble protein fractions and amino acid composition. These plants can be a substitution of each other as well as for cereals.  相似文献   

Vegetation response to a topographical-soil gradient     

Jerzy Solon  Marek DegórskiEwa Roo-Zielińska 《CATENA》2007

Plant cover is an easily discernible, recognisable and labile component of the natural environment that reacts to changes in other components. One of the more important components controlling vegetation cover is the soil, and both vegetation and soil are influenced by topography, amongst other things. As it is in the humus-accumulation horizon of soils that vascular plants have most of their roots, these species are capable of reacting to qualitative and quantitative differences in its composition. The relationship between topography, soil and vegetation were assessed on the basis of three catenal sequences representative of Poland's Wigierski (Lake Wigry) National Park. The aim was to determine if changes in soil along the catenae were reflected in changes in plant community (species richness, species composition, and indicator species). We made use of soil analysis, phytosociological analysis of vegetational structure, and Ellenberg indicator values. Correlations between 23 variables allowed distinguishing 6 statistically-significant groups of variables with main ordinating groups being the percentage shares of species indicating relatively dry, slightly moist soils, the combined shares of these species, altitude above sea level and relative elevation. The first two axes of a Principal Components Analysis were strongly related to soil moisture and elevation (axis 1) and to soil fertility (axis 2). Together, these axes accounted for more than 60% of the variability. Within the forest communities, however, fertility was the most important factor. The three catenae differed most in terms of their species richness and least in soil characteristics. An intermediate place was taken by the weighted Ellenberg's indicator values. The lower sections of catenae were found to have more similarity in terms of soil, vegetation and their interrelationships and patterns than the upper parts.  相似文献   

The effect of the source and dosage of dietary Cu on redox status in rat tissues     

Katarzyna Ognik  Ewelina Cholewińska  Krzysztof Tutaj  Monika Cendrowska-Pinkosz  Wojciech Dworzański  Anna Dworzańska  Jerzy Juśkiewicz 《Journal of animal physiology and animal nutrition》2020,104(1):352-361

The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO₃ or copper nanoparticles). Replacing the CuCO₃ supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO₃ with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain.  相似文献   

Pollution indices and biotests as useful tools for the evaluation of the degree of soil contamination by trace elements     

Wieczorek  Jerzy  Baran  Agnieszka 《Journal of Soils and Sediments》2022,22(2):559-576

Journal of Soils and Sediments - The aim of the study was the calculation of geochemical, ecological, and ecotoxicological indices for the assessment of risk resulting from the presence of trace...  相似文献   

A receptor for tumor necrosis factor defines an unusual family of cellular and viral proteins   总被引：89，自引：0，他引：89  

C A Smith  T Davis  D Anderson  L Solam  M P Beckmann  R Jerzy  S K Dower  D Cosman  R G Goodwin 《Science (New York, N.Y.)》1990,248(4958):1019-1023

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The Presence of Nitrates and the Impact of Ultraviolet Radiation as Factors that Determine Nitrate Reductase Activity and Nitrogen Concentrations in Deschampsia antarctica Desv. Around Penguin Rookeries on King George Island,Maritime Antarctica     

Krywult  Marek  Smykla  Jerzy  Wincenciak  Adam 《Water, air, and soil pollution》2013,224(5):1-12

This paper addresses the oxidation by ultraviolet radiation of methylparaben, a ubiquitous and suspicious preservative which is massively added to cosmetics and personal care products. Experiments included pH and temperature variation, as well as several experimental conditions such as presence/absence of hydrogen peroxide, titanium dioxide, or some different water matrix (surface water or ground water). Results were evaluated under the line source spherical emission model, so quantum yield was the adequate target variable for explaining the process. A modified Arrhenius correlation including pH level was used for modelling the whole system.  相似文献   

Potato after-cooking darkening   总被引：2，自引：0，他引：2  

Gefu Wang-Pruski  Jerzy Nowak 《American Journal of Potato Research》2004,81(1):7-16

After-cooking darkening (ACD) is one of the most widespread, undesirable characteristics of cultivated potato. With the current expansion of the potato-processing industry around the world, there is a renewed interest in the development of new ways to prevent ACD. After-cooking darkening is caused by the oxidation of the ferri-chlorogenic acid in the boiled or fried potatoes. The severity of the darkening is dependent on the ratio of chlorogenic acid to citric acid concentrations in the potato tubers. Higher ratio normally results in darker tubers. The concentration of the chlorogenic and citric acids is genetically controlled and influenced by environmental conditions. This paper outlines the history of ACD and current status of knowledge of the chemistry of the dark pigment formation and its genetic and environmental determinants. Also discussed are the methods of chemical prevention of ACD presently used by the potato-processing industry and potential strategies for reducing tuber after cooking darkening using molecular approaches.  相似文献   

Acrosin system of dog spermatozoa and reproductive tract secretions     

Strzezek R  Koziorowska-Gilun M  Filipowicz K 《Polish journal of veterinary sciences》2010,13(1):69-73

The aim of this study was to determine the activity of proacrosin and acrosin in spermatozoa originating from the sperm-rich fractions (SRF) and whole ejaculates (WE) of dog semen. In addition, experiments were conducted to determine the activity of antitrypsin inhibitors in the fluids of different ejaculate fractions and whole seminal plasma. Ejaculates were collected from five dogs of mixed breed and one Beagle dog (aged from 2 to 9 years). In the SRF, it was confirmed that the activity of the free acrosin form was predominant (acrosin/proacrosin; 2.38 +/- 0.22/1.05 +/- 0.08 mIU/10(6) spermatozoa). On the other hand, spermatozoa originating from the WE exhibited significantly higher (p < 0.05) proacrosin activity (proacrosin /acrosin; 2.19 +/- 0.19/1.30 +/- 0.11 mIU/10(6) spermatozoa). Furthermore, acrosin inhibitor activity was lower in the fluids of the pre-sperm fraction (0.09 +/- 0.006 IU/cm3), whereas it was higher in the fluids of the post-sperm fraction (0.11 +/- 0.007 IU/cm3). Using PAGE analysis, the antitrypsin activity of the enzyme was represented by the presence of one electrophoretic band in the fluids of the pre-sperm and post-sperm fractions and whole seminal plasma. Furthermore, two electrophoretic bands were detected in the fluids of the SRF. The findings of this study indicate that specific proteinase inhibitors present in the individual ejaculate fractions of dog semen may act by stabilizing the sperm acrosin system.  相似文献   

Spatial and temporal variability of natural regeneration in a temperate old-growth forest     

Janusz Szewczyk  Jerzy Szwagrzyk 《Annals of Forest Science》2010,67(2):202-202

? The natural regeneration of shade-tolerant tree species is characterized by large spatial heterogeneity and temporal variability. The mechanisms producing those patterns are still poorly understood and the knowledge of long-term fluctuations in regeneration processes is very limited.

? We used data from long-term study plots in an old-growth stand dominated by European beech and silver fir to address three questions: (1) Is a tendency towards clumping in seedlings associated with a particular spatial scale? (2) Are the spatial patterns in seedlings constant over time? (3) Is the distribution of seedlings related to light intensity?

? Over the study period the seedling density varied from 2.5 to 6 ind./m². Stronger fluctuations occurred at a fine scale. Seedlings were clumped at distances ranging from a few centimeters to a few meters. The distribution of places with high seedling densities was relatively constant over time, especially in beech. Positive but weak rank correlations were found between light intensity and densities of beech and fir seedlings.

? Despite large fluctuations in seedlings densities, caused by mast-seeding, a permanent seedling bank was maintained. Very pronounced clumping of tree seedlings found in this study was only partially explained by differences in light intensity.

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