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Nikola Pernar Darko Baksic Oleg Antonic Marijan Grubesic Ivica Tikvic Mladen Trupcevic 《Water, air, and soil pollution》2006,177(1-4):267-284
Research on oil residuals in lowland forest soil was carried out in 6 sample plots in the lowland forest ecosystem located in an oil field. Four plots were differently affected in terms of discharged oil and the time lapsed after the accident, as well as in terms of micro-relief terrain features. One plot was established in a reclaimed mud ditch site, while the control plot was set up in a micro-relief elevation outside the influence of oil pollution. Total petroleum hydrocarbon (TPH) concentrations were measured at three soil depths at the beginning and the end of the vegetation period. The analysis of the results revealed significant differences in petroleum hydrocarbon concentrations among the sites. Increased TPH concentrations were recorded in several plots, while the values measured in some other plots indicated very low quantities of residual TPH in the soil. The highest average TPH concentrations (200–400 mg kg1) were recorded in the mud ditch site. In one of the plots exposed to oil pollution after an oil pipe rupture, there was the constant presence of increased TPH concentration in the surface soil part (≥200 mg kg1 on average). The sporadic presence of increased TPH concentrations in micro-depressions that cannot be attributed to a local accident indicates seasonal soil pollution with petroleum carbohydrates from floodwater. The soil in the sample plots is not contaminated with soluble salts or heavy metals. Low values of TPH concentrations in the soil water eluate indicate that the soil does not represent a source of hydrospheric pollution with petrol hydrocarbons. 相似文献
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Soil microbial activities in tree-based cropping systems and natural forests of the Central Amazon,Brazil 总被引：1，自引：0，他引：1
Oleg?V.?MenyailoEmail author Johannes?Lehmann Manoel?da?Silva Cravo Wolfgang?Zech 《Biology and Fertility of Soils》2003,38(1):1-9
Little information is available about the factors controlling soil C and N transformations in natural tropical forests and tree-based cropping systems. The aim of this work was to study the effects of single trees on soil microbiological activities from plantations of timber and non-timber species as well as species of primary and secondary forests in the Central Amazon. Soil samples were taken in the primary forest under Oenocarpus bacaba and Eschweilera spp., in secondary regrowth with Vismia spp., under two non-timber tree species ( Bixa orellana L. and Theobroma grandiflorum Willd.), and two species planted for wood production ( Carapa guianensis Aubl. and Ceiba pentandra). In these soils, net N mineralization, net nitrification, denitrification potential, basal and substrate-induced respiration rates were studied under standardized soil moisture and temperature conditions. Individual tree species more strongly affected N transformations, particularly net nitrification, than C respiration. Our results suggest that soil C respiration can be affected by tree species if inorganic N becomes a limiting factor. We found a strong correlation among almost all microbiological processes suggesting close inter-relationship between C and N transformations in the studied soils. Correlation analysis between soil chemical properties and microbiological activities suggest that such strong inter-relationships are likely due to competition between the denitrifying and C-mineralizing communities for NO 3 -, which might be an important N source for the microbial population in the studied soils. 相似文献
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Vera A. MATROSOVA Anastasia D. IVANOVA Elena V. VOLODINA Ilya A. VOLODIN Dmitry Yu. ALEXANDROV Olga V. SIBIRYAKOVA Oleg A. ERMAKOV 《Integrative zoology》2019,14(4):341-353
Distribution area and taxonomic borders within the species complex Spermophilus erythrogenys sensu lato remain questionable. Early evidence suggests that red‐cheeked ground squirrels of Southeast Kazakhstan are remarkably different in terms of the acoustic structure of their alarm calls from the red‐cheeked ground squirrels of the Kurgan region in Russia. In this study, we analyzed the differences in the acoustic structure of the alarm call and mitochondrial DNA (complete control region, 1005–1006 bp and complete cytochrome b gene, 1140 bp) in 3 populations of red‐cheeked ground squirrels (Tara, Altyn‐Emel and Balkhash), all located within areas isolated by geographical barriers in Southeast Kazakhstan. We found that the alarm call variables were similar between the 3 study populations and differed by the maximum fundamental frequency (8.46 ± 0.75 kHz) from the values (5.62 ± 0.06 kHz) reported for the red‐cheeked ground squirrels from the Kurgan region of Russia. Variation in mtDNA control region was only 3% and variation in cytochrome b gene was only 2.5%. Phylogenetic trees based on cytochrome b gene polymorphism of 44 individuals from the study area and adjacent territories indicated 3 clades with high (98–100%) bootstrap support: “intermedius,” “brevicauda” and “iliensis”). We conclude that the 3 study populations in Southeast Kazakhstan belong to the clade intermedius and suggest a taxonomical revision of the species complex Spermophilus erythrogenys sensu lato, including analyses of nuclear DNA and alarm calls for populations of the brevicauda and iliensis clades. 相似文献
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Ali Irfan Ilbas Semih Yilmaz Mikail Akbulut Oleg Bogdevich 《Journal of plant nutrition》2013,36(3):442-452
Selenium (Se) is an essential micronutrient for humans and animals, and also affects plant metabolism. In this study, the effects of increasing doses of Se application on the uptake of selenium (Se), nitrogen (N), and sulfur (S) content of three barley cultivars were investigated. The analysis indicated that the Se contents were highest in root tissues, intermediate in grain, and lowest in stem tissues in all cultivars. Total Se accumulations (whole plant) were highest in ‘Bülbül 89’ (0.171 mg kg?1), intermediate in ‘Çetin 2000’ (0.153 mg kg?1), and lowest in ‘Tarm 92’ cultivars (0.124 mg kg?1). In all cultivars, the increase in grain Se content resulted in a decrease in the grain N content. While ‘Bülbül 89’ can be suggested for biofortification purposes, less Se accumulating ‘Tarm 92’ cultivar can be suggested as a fodder in Se contaminated or high Se containing areas. 相似文献
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Thomas R. Gordon Oleg Daugovish Steven T. Koike Christina M. Islas Sharon C. Kirkpatrick Jenna A. Yoshisato 《International Journal of Fruit Science》2016,16(4):160-168
ABSTRACTThe emergence of Fusarium wilt, caused by Fusarium oxysporum f. sp. fragariae, as a problem for strawberry production in California has been associated with delivery of fumigants to beds through drip-lines rather than flat-fumigation of an entire field. Our research shows that bed fumigation fails to eliminate propagules of the Fusarium wilt pathogen, which remain particularly abundant in bed shoulders at a depth of 30 cm. Controlled environment studies confirmed that inoculum at this depth could cause disease. Screening of currently grown strawberry cultivars documented a wide range of susceptibilities to Fusarium wilt, with some being highly resistant. 相似文献
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Methane consumption by temperate forest soils is a major sink for this important greenhouse gas, but little is known about how tree species influence CH4 uptake by soils. Here, we show that six common tree species in Siberian boreal and temperate forests significantly affect potential CH4 consumption in laboratory microcosms. Overall, soils under hardwood species (aspen and birch) consumed CH4 at higher rates than soils under coniferous species and grassland. While NH4+ addition often reduces CH4 uptake, we found no effect of NH4+ addition, possibly because of the relatively high ratio of CH4-to-NH4+ in our incubations. The effects of soil moisture strongly depended on plant species. An increase in soil moisture enhanced CH4 consumption in soils under spruce but had the opposite effect under Scots pine and larch. Under other species, soil moisture did not affect CH4 consumption. These results could be explained by specific responses of different groups of CH4-oxidizing bacteria to elevated moisture. 相似文献
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