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41.
The following parameters were determined in the interstitial waters of the Gulf of Gdańsk and the Pomeranian Bay: nutrients (ammonia and phosphates), sulphates, total iron and iron(II) concentrations. Redox potential (Eh), pH, humidity and organic matter content measured as a loss on ignition were determined in bottom sediments from these regions. Interstitial waters of both regions were found to have reducing character (Eh < 250 mV). Reduction processes were more advanced in the Gulf of Gdańsk, rich in organic matter, as evidenced by lower values of the redox potential, lower Fe(III)/Fetot ratio, and incidents of sulphates exhaustion. 相似文献
42.
Turek Marian Korolewicz Teofil Ciba Jerzy Cebula Jan 《Water, air, and soil pollution》2002,135(1-4):311-323
Total content of zinc and other metals has been assayed in thesludge that remained after leaching zinc-bearing smelting losswith sulfuric acid. The paper also presents zinc speciationcarried out by means of the sequential extraction by Rudd and an analysis of chemical forms of zinc. It has been found thatzinc occurs mainly in the mobile, bioavailable, soluble form and in the moderately mobile, carbonate form. The speciationcarried out showed that zinc occurred in the sludge in the following forms (mg kg-1): sulfate 143 000, oxide 79 000,metallic 68 200, siliceous 35 500, sulfide 20 800 and ferrate18 500. Preparatory extraction of zinc from the sludge usingwater, sodium salt of ethylenediaminetetraacetic acid (EDTA)and acetic acid has also been conducted. 相似文献
43.
Summary In earlier work on improvement of persistance in forage legumes, we selected genotypes from highly productive cultivars of alfalfa, Algonquin and Apica (Euphytica 45: 105–112, 1990) and cv. Florex red clover (Plant Cell Reports 8: 395–398, 1989) capable of in vitro regeneration from callus and cell culture. The alfalfa germplasm and its F1 progeny as well as an F2 red clover population were tested for cold stress tolerance. Plantlets were hardened in culture tubes at 2 or 5°C, 8h photoperiod, for at least four weeks and then subjected to freezing temperatures, –16 or –10°C for alfalfa and red clover, respectively. Survival of regenerative genotypes was significantly higher than of the non-regenerative ones in both species. A strong oositive correlation (r=0.78) between the regenerative trait and plant survival was found in alfalfa. The experiments indicate that in vitro selection for regenerative trait may improve cold stress tolerance of alfalfa and red clover. 相似文献
44.
Tadeusz Adamski Jerzy Chełkowski Zygmunt Kaczmarek Maria Surma Halina Wiśniewska 《Euphytica》1997,93(2):169-172
Auto- and alloplasmic doubled haploid (DH) lines of barley were examined for susceptibility to Fusarium culmorum (W.G.Sm.) Sacc. (isolate KF350) seedling blight. Inoculated kernels were incubated at 20 °C in a chamber saturated to 100% RH a with 12/12 h dark/light cycle. Germination capacity, disease score on a 5-degree scale and root length were evaluated. The data were analysed statistically using three-factor analysis of variance. It was observed that the infection score of roots of DH lines with H. bulbosum cytoplasm was higher than that of their autoplasmic analogues. Length of infected seedling roots expressed as per cent of the control root length ranged from 81 to 56% in autoplasmic DH lines and from 60 to 48% in alloplasmic lines. These differences were statistically significant (at P = 0.01). It was evident, that H. bulbosum cytoplasm increase susceptibility of barley genotypes to Fusarium seedling blight. 相似文献
45.
Jerzy Bartnicki 《Water, air, and soil pollution》1994,75(3-4):227-263
This paper presents the Heavy Metals Eulerian Transport (HMET) model and simulation results for Europe for 1985. The HMET model takes into account emission, atmospheric transport and deposition of As, Cd, Pb and Zn computed on the EMEP grid system. Meteorological inputs consist of the velocity field at 925 hPa, precipitation and mixing height. Velocity field and precipitation are updated every 6 hr during the model run. New values of mixing height are available every 24 hr. The dry deposition velocities for each metal are variable in space and depend on the particle distribution function for each particular metal. Wet deposition is proportional to the precipitation intensity for the previous 6 hr and a constant scavenging ratio. Model equations are solved by means of the positive definite pseudospectral method which provides accurate numerical solutions for the advection problem. Comparison of the model results with available observations for 1985 indicate a good agreement for Cd and Pb, sufficient egreement for As and serious underestimation for Zn. Since the number of available observations for heavy metals in Europe in 1985 is relatively small, the model results presented in this paper should be considered as preliminary. However, the HMET model performance in computing these results shows that it can be easily and efficiently used as an operational tool and is especially useful for estimating transboundary transport of heavy metals in Europe. 相似文献
46.
Zołotajkin M Ciba J Kluczka J Skwira M Smoliński A 《Water, air, and soil pollution》2011,216(1-4):571-580
The research was carried out in the spruce forests of Barania Góra (Silesian Beskids, Poland) affected by pandemic dying of trees. Twenty-seven samples were collected from the O layer in two plots: 17 in a cut down forest infested with insect pests (bark beetle) and ten in a 120-year-old healthy forest. The analyses covered basic parameters (pH(H2O), pH(KCl), w(org), C(tot), N(tot), CEC) and the concentrations of aluminium in the fractions leached with 0.1?M BaCl(2) (Al(exch)), 0.5?M CuCl(2) and 0.1?M Na(4)P(2)O(7) (Al(bio)) solutions. The total aluminium concentration in the soil was assayed digesting samples with hydrofluoric acid. The effect of pH and organic matter content on the amount of exchangeable (Al(exch)) and bioavailable (Al(exch)) aluminium in the soil was analysed. It has been found that the soils in both plots are strongly acidic and contain 550 to 1,700?mg?kg(-1) of exchangeable aluminium and 1,200 to 4,800?mg?kg(-1) of bioavailable aluminium. The lack of disease symptoms in the spruce trees in plot 2 can be explained by the higher content of organic matter in the soil. Unfortunately, one might expect that the high concentration of exchangeable aluminium will also cause the trees in the area to wither. 相似文献
47.
48.
Dominika Guzek Dominika Głąbska Krystyna Gutkowska Jerzy Wierzbicki Alicja Woźniak Agnieszka Wierzbicka 《Animal Science Journal》2015,86(3):333-339
The aim of the study was to analyze the factors creating consumer attributes of roasted beef steaks of various animals. Eight cuts from 30 carcasses (characterized by various types of animal, conformation and fat class, rib fat thickness, ossification score) were selected. Samples were prepared using the roasting method and consumers rated the tenderness, juiciness, flavor, overall acceptability (rated in a 100‐point scale), and satisfaction (rated from 2 to 5) for analyzed samples. No influence of type of animal, fat class, conformation class or ossification score on the results of consumer analysis was observed. For all analyzed factors, the influence of cut on consumer analysis was observed (the highest values of all consumer attributes were observed for tenderloin ‐ for juiciness significantly higher than for other cuts, for tenderness, flavor and MQ4 comparable only with rump (RMP231), while for overall acceptability and satisfaction – with both rump cuts). For rib fat thickness consumer attributes of roasted beef meat were not linear, but the influence was observed – the highest values of consumer attributes were observed for 13 mm rib fat thickness. 相似文献
49.
Fernando Teixeira Tatenda Lemann Carla Ferreira Matjaž Glavan Tóth Zoltán Tamás Hermann Jerzy Lipiec Magdalena Frąc Endla Reintam Minggang Xu Hongzhu Fan Coen Ritsema 《Soil Use and Management》2023,39(1):474-484
This study investigates 11 agricultural management practices (AMPs) and their effects on seven visual soil quality indicators and soil aggregate stability. The survey carried out across eight pedoclimatic zones in Europe and China was based on visual soil assessments (New Zealand VSA method) performed on soils subject to different soil management practices and nearby similar soils, under similar farming features, without the distinctive soil management practice (control). Fisher's exact test was used to test if the management treatment was independent of the score of each visual soil quality indicator and to test if the management treatment produced a higher frequency of the score ‘good’. The results showed a statistically significant (α < .05) higher frequency of the score ‘good’ for ‘soil structure and consistency’ and/or ‘soil porosity’ for six AMPs. For no-till AMP, the null hypothesis can also be rejected for ‘susceptibility to erosion’ and ‘soil stability’ and for ‘mulching + permanent soil cover’ AMP, for the ‘presence of tillage pan’ and ‘soil colour’. The hypothesis that the management treatment was independent of the score of each indicator was rejected for ‘soil structure and consistency’ of three AMPs, for ‘soil porosity’ of three AMPs, for ‘soil colour’ of one AMP and for the ‘presence of tillage pan’ of one AMP. This study demonstrates that farming systems sharing a common influential soil management practice at different locations and with different soil types significantly affect the score of some visual soil quality indicators. 相似文献
50.
Jakub Bekier Jerzy Drozd Elżbieta Jamroz Bogdan Jarosz Andrzej Kocowicz Karolina Walenczak Jerzy Weber 《Journal of Soils and Sediments》2014,14(2):305-311