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31.
Milica Marković Tea Zuliani Snežana Belanović Simić Zorana Mataruga Olga Kostić Snežana Jarić Janja Vidmar Radmila Milačič Janez Ščančar Miroslava Mitrović Pavle Pavlović 《Journal of Soils and Sediments》2018,18(12):3404-3414
Purpose
Riparian zone contamination is a growing problem for several European catchments due to high anthropogenic pressures. This study investigates As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in the Sava River riparian zone, characterized by wide agricultural areas, various geological substrates, and different types of industrial pollution. The accumulation and mobility of these elements were studied because they are listed as priority substances in the Water Framework Directive and environmental objectives for surface waters.Materials and methods
Sampling was performed during the sampling campaign of the EU 7th FW-funded GLOBAQUA project in September 2015 during a low-water event. Soil samples were collected along the Sava River at 12 selected sampling sites, from a depth of 0–30 cm, at a distance of 10–15 m from the river bank. The extent of pollution was estimated by determining total and readily soluble element concentrations in the soils. Potential ecological risk and the source of the selected elements in the soils was determined using the enrichment factor (EF), potential ecological risk index (RI), and statistical methods such as the principal component analysis (PCA) and multiple linear regression analysis (MLRA).Results and discussion
This study showed that concentrations of the selected elements increase along the Sava. In terms of origin, PCA and MLRA indicated that Cr and Ni in soils are predominantly lithogenic, while As, Cd, Pb, and Zn are both lithogenic and anthropogenic (ore deposits, industry, and agriculture). PCA singled out Cu since its origin in soil is most probably from specific point-source pollution. EF was generally minor to moderate for most of the examined elements, apart from Cu, for which the EF was significant at one sampling site. Overall ecological risk (RI) fell within the low-risk category for most sites, apart from Belgrade sampling site (BEO), where high total Cd content affected individual and overall ecological risk indicators, indicating Cd could represent a considerable ecological risk for the downstream riparian zone.Conclusions
At downstream sites, there was a noticeable increase in PTE content, with Cd, Cr, Ni, and Zn exceeding the proposed threshold values for European soils, indicating rising contamination in riparian soils. In terms of the ecological risk, only Cd could pose a potential ecological threat for the downstream riparian zone.32.
Multilocus PCR assay reveals high diversity of vegetative compatibility types in populations of Cryphonectria parasitica in Croatia 下载免费PDF全文
The ascomycete fungus Cryphonectria parasitica, causal agent of chestnut blight, is probably one of the best known invasive fungal pathogens in forests of Europe and North America. Mycovirus that reduces virulence of C. parasitica can be used as a biocontrol agent of the chestnut blight. However, anastomosis‐mediated virus transmission is limited by a vegetative (in)compatibility (vc) system involving at least six known diallelic vic genetic loci. This study looked at vegetative compatibility (vc) diversity in two populations of C. parasitica in Croatia. For that purpose, a PCR assay was validated and implemented using already known/published and newly designed primers for amplification of six known vic loci. The vc genotypes determined by PCR for 158 C. parasitica isolates investigated in this study were in complete agreement with the vc genotypes determined by pairwise co‐culturing of the same isolates, revealing the specificity and accuracy of the PCR‐based molecular vic genotyping assay. Twenty‐six unique vc genotypes were found among 158 isolates, and 19 vc types per population, which makes Croatian C. parasitica populations among the most diverse in Europe regarding the number of vc types and genetic diversity. Low values of multilocus linkage disequilibrium suggest sexual reproduction as a major contributor to high C. parasitica genetic diversity in studied populations. 相似文献
33.
Ivana Šola Mirta Stipaničev Valerija Vujčić Božena Mitić Ana Huđek Gordana Rusak 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):189-195
Native Crocus taxa are abundant in regions with moderate and dry climate; however, their potential in the food industry has thus far been neglected. The objective of this study was to compare the quantitative and qualitative flavonoid content and antioxidant and cytotoxic activity in organs of several populations of Croatian native taxa and assess their potential for application in the food industry. The dominant flavonoids in the native Crocus taxa were kaempferol and quercetin. Tepals contained similar or higher concentrations of flavonoid-glycosides than other organs. Tepals from Cvv1 and Cvv2 populations contained more flavonoid-glycosides than the commonly used spice saffron (C. sativus stigmas). The FRAP antioxidant activity of Cvv1 and Cvv5 tepals was similar to that of standard Trolox. DPPH inhibition of Cvv1 and Cvv3 tepals was within the range of that recorded for saffron. Cvv1 tepals significantly reduced reactive oxygen species in the broadest concentration range (50–1000 μg/ml), and showed considerable antioxidant activity in the ABTS assay, equal to 82% of standard Trolox antioxidant activity. A significantly higher concentration of kaempferol-rutinoside was recorded in this than in other taxa. The flavonoid showed a very strong or strong correlation with antioxidant assays results, and a negative correlation with cellular reactive oxygen species concentration. We therefore presumed that kaempferol-rutinoside is one of the main antioxidant phenolics in Crocus tepals. None of the tested extracts showed cytotoxicity toward Caco-2 cells. The results revealed that Cvv tepals have potential as a food supplement and are a promising material for further food safety tests. 相似文献
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35.
Plavec Jelena Križanac Ivana Budinšćak Željko Škorić Dijana Musić Martina Šeruga 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):591-601
European Journal of Plant Pathology - Uncultivable bacteria from the genus ‘Candidatus Phytoplasma’ are associated with grapevine yellows (GY) diseases worldwide. In Euro-Mediterranean... 相似文献
36.
Degradation Kinetics of an Aged Hydrocarbon-Contaminated Soil 总被引:1,自引:0,他引:1
Snežana Maletić Božo Dalmacija Srđan Rončević Jasmina Agbaba Olgica Petrović 《Water, air, and soil pollution》2009,201(1-4):149-159
PM2.5 and PM10 samples were collected in the urban atmosphere of Elche (southeastern Spain) between December 2004 and November 2005. The samples were analyzed for mass and water-soluble inorganic ions (Na+, ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ , K+, Ca2+, Mg2+, Cl?, ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ ) with the aim of investigating the influence of the climatic and geographic features of a coastal semiarid area on the contribution of these species to PM levels. Secondary inorganic ions ( ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ , ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ , ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ ) were the major components in the fine fraction (PM2.5), accounting for 40% of the total mass. The relationship between non-marine ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ and ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ indicated that fine sulfate particles were completely neutralized by ammonium. In the coarse fraction (PM10–2.5), nitrate (as NaNO3 and Ca(NO3)2), together with crustal (CaCO3) and marine species (NaCl) accounted for almost 50% of the total mass. Fine sulfate and coarse nitrate showed summer maximums. In contrast, the concentrations of fine ${\text{NO}}^{{\text{ - }}}_{{\text{3}}}$ were lowest in the warm period. Ammonium presented both winter and summer maximums. The levels of marine ions, except for coarse Cl?, were highest in summer when the dominant wind flow is from the sea. No significant seasonal variations were observed for coarse Ca2+ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ . The concentrations of all inorganic ions increased during Saharan dust events, in particular, fine ${\text{NH}}^{{\text{ + }}}_{{\text{4}}}$ and ${\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}}$ and coarse $NO_3^ - $ . Coarse calcium was proved not to be a good tracer for this type of episode in our region since the average levels of this cation are elevated and the relative increase in its concentrations during African events was not as high as expected. 相似文献
37.
Ternjej Ivančica Stanković Igor Mihaljević Zlatko Furač Lidija Želježić Davor Kopjar Nevenka 《Water, air, and soil pollution》2009,204(1-4):299-314
Water, Air, & Soil Pollution - In this pilot study, we evaluated the usefulness of the alkaline comet assay as a biomonitoring tool at the level of plankton communities affected by varying... 相似文献
38.
Despite the increasing recognition of riparian zones as important ecotones that link terrestrial and aquatic ecosystems and of fire as a critical natural disturbance, much remains unknown regarding the influence of fire on stream-riparian ecosystems. To further this understanding, we evaluated the effects of mixed severity wildfire on riparian plant community structure and composition in headwater streams of the Big Creek Watershed of the Frank Church ‘River of No Return’ Wilderness of central Idaho. Five years after a large stand-replacing fire, we conducted riparian vegetation surveys at sixteen reaches across a range of burn types. Non-metric Multidimensional Scaling (NMS) and Multi-Response Permutation Procedure (MRPP) analyses showed an overall shift in community composition and structure between vegetation at unburned and severely burned reaches. Although total plant cover was significantly less at severely burned areas, recovery of the deciduous understory was apparent. Severely burned reaches were characterized by a marked increase in cheatgrass (Bromus tectorum). Reaches that were exposed to low-severity fire were indistinguishable from unburned reaches relative to vegetation community composition and structure, pointing to a possible disturbance threshold that may need to be crossed in order to alter riparian plant communities. 相似文献
39.
40.
Cherry laurel (Prunus laurocerasus) is a native plant species in Serbian forests, but is also widely used for ornamental plantings. Following two extremely wet summers in 2014 and 2015, in spring and summer of 2016 and 2017, numerous cherry laurel plants with symptoms indicative for Phytophthora diseases, like wilting and chlorosis of leaves, dieback and bleeding bark necroses, were recorded in a park in Belgrade and in two ornamental nurseries in central Serbia. From necrotic bark samples and rhizosphere soil, self‐sterile Phytophthora isolates with woolly colonies were obtained. Due to the production of ellipsoid and elongated, non‐papillate sporangia in water and of ornamented oogonia with two‐celled antheridia in mating tests with tester strains of both Phytophthora × cambivora and P. cryptogea, these isolates were identified as P. ×cambivora which was confirmed by ITS sequence analysis. Pathogenicity of P. ×cambivora from cherry laurel (PCCL) was tested by inoculating one‐year‐old seedlings of cherry laurel under the bark. P. ×cambivora from European beech (PCB), and isolates of P. cactorum (CAC), P. cryptogea (CRY), P. plurivora (PLU) and P. ×serendipita (SER) were included as comparison. Three and a half months after inoculation, nine of the twelve plants in PCB, three in PCCL and CAC and two in PLU declined with longitudinal necroses and chlorosis, wilting and premature shedding of leaves. These results demonstrate the ability of P. ×cambivora to infect and cause decline of cherry laurel plants. The particularly high aggressiveness of the P. ×cambivora isolate from beech shows that this pathogen poses a serious risk to cherry laurel in the rare natural communities of cherry laurel and beech in Serbia. 相似文献