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51.
Soil pH, soil organic matter (SOM), dissolved organic carbon (DOC) and total trace metal concentration (M(tot)) control the solubility of metals in the soil. Several regression models have included these soil chemical variables for the prediction of metal solubility and free metal ion (FMI) concentrations in contaminated soils. We hypothesize that models developed on contaminated soils (after optimization of the coefficients) can be used on samples from uncontaminated sites. Soil samples were collected from unpolluted agricultural and forest soils located in Eastern Croatia and extracted with water to determine the concentrations of Cd, Cu, Pb and Zn. We used these data to test the applicability of three regression models on existing conditions under different land uses. The same predictors issued in the three models and the same regression coefficients were utilized in the present study. The results showed a good correlation between the observed and predicted values of metal solubility. However, the models overestimate the total solution concentration (M(sol)) and the concentrations of free metal ions (FMI) in solution, and therefore the same regression coefficients were optimized to fit our own observations. This was found to be very successful. The results showed that pH and DOC played a very important role in controlling metal solubility, while SOM and CEC were somewhat less significant. The impact of total soil concentration of metals (M(tot)) was rather minor. However, we feel that to carry out good predictions of M(sol) and FMI, the M(tot) is needed in such regression models. 相似文献
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Iori Valentina Pietrini Fabrizio Cheremisina Alexandra Shevyakova Nina I. Radyukina Nataliya Kuznetsov Vladimir V. Zacchini Massimo 《Water, air, and soil pollution》2013,224(2):1-10
Surfactant-enhanced solubilization and subsequent biodegradation of phenanthrene and pyrene from aqueous solutions by Arthrobacter strain Sphe3 was investigated. The results show that growth of Arthrobacter strain Sphe3 was increased upon increase in concentration of Tween 20 and Tween 80. Inhibition of bacterial growth was observed with increasing Triton X-100 concentrations, whereas sodium dodecyl sulfate (SDS) totally inhibited this bacterial growth. Phenanthrene and pyrene solubilization was enhanced in the presence of surfactants and found to be linearly proportional to their concentrations, above the critical micelle concentration (CMC). In addition, Tween 20 and Tween 80 enhanced the biodegradation of phenanthrene and pyrene. The high correlation coefficient (R 2) values obtained at all the concentrations studied, suggest that biodegradation kinetics of both phenanthrene and pyrene in the presence of Tween 20 and Tween 80 follow first-order kinetic equation model. Experimental results suggest that Tween 20 and Tween 80 may have great potential for applications in bioremediation of these polycyclic aromatic hydrocarbon (PAH) compounds using Arthrobacter strain Sphe3. 相似文献
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Growth responses to phosphorus (P) and iron (Fe) are commonly assessed based on element concentrations to which plants are exposed. Such data offer little insight about responses to the concentration of P and Fe actually accumulated in plants. In this study, soybean (Glycine max Merr., cv. ‘Biloxi’) was grown on nutrient solutions to induce varying P and Fe concentrations in plant tissues. Leaf P and Fe concentrations were correlated at lower concentrations. However, under high P treatments there was an apparent excess of accumulated P based on plant response. These results were interpreted to indicate that these plants could accumulate P in excess of the amount required for normal physiological activity. There appeared to be no excess accumulation of Fe so that correlations between leaf Fe concentration and leaf area and plant mass were significant for all data. Root mass did not correlate significantly with either leaf P or Fe concentration. 相似文献
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Yarmeeva Maria M. Kokaeva Lyudmila Y. Chudinova Elena M. Kah Masamba O. Kurchaev Michael L. Zeyruk Vladimir N. Belov Grigoriy L. Bairambekov Shamil B. Elansky Sergey N. 《植物病害和植物保护杂志》2021,128(5):1253-1261
Journal of Plant Diseases and Protection - A survey of Rhizoctonia solani isolates from potato tubers and stems grown in European and Far Eastern regions of Russia in 2012–2020 was conducted.... 相似文献
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Brito Giovani G. Concenço Germani Costa Vladimir E. Fagundes Paulo Ricardo R. da Silva-Filho João Luis Parfitt José Maria B. Magalhães Ariano Silva Giovana T. Jardim Thaís M. Luccas Nathália Furtado Scivittaro Walkyria B. 《Journal of Crop Science and Biotechnology》2022,25(1):19-32
Journal of Crop Science and Biotechnology - Phenotyping is the major bottleneck in the effort to develop varieties of rice (Oryza sativa L.) suitable for growing under a water-saving irrigation... 相似文献
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Effects of travel distance and season of the year on transport‐related mortality in cattle 下载免费PDF全文
Veronika Simova Eva Voslarova Vladimir Vecerek Annamaria Passantino Iveta Bedanova 《Animal Science Journal》2017,88(3):526-532
The number of animals that die during transport to a slaughterhouse or shortly after being delivered to a slaughterhouse may serve as an indicator of animal welfare during transport. The aim of this study was to determine the mortality rate in cattle resulting from transport to slaughter in the Czech Republic in the period from 2009 to 2014, and to investigate the effect of travel distance and season of the year. Transport‐related mortality rates were recorded for all categories of cattle for the following travel distances: up to 50 km, 51–100 km, 101–200 km and over 200 km. Higher mortality rates occurred with shorter travel distances (<50 km and 51–100 km) when compared to longer travel distances (101–200 km and > 200 km), with a significant difference (P < 0.01) between short and long travel distances being found in feeders and dairy cows. Also, the season of the year had a significant impact on the mortality rate among transported cattle. The highest mortality rate in all categories was observed in spring months. The lowest mortality rate was found in autumn months for fat cattle and dairy cows and in winter months for feeders and calves. 相似文献
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Aleksandr Semjonov Jacobus P. Raath Liesel Laubscher Toomas Orro Silke Pfitzer Toomas Tiirats Peter Stewart Rogers Vladimir Andrianov 《Veterinary anaesthesia and analgesia》2019,46(1):90-95