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11.
Bothe Hermann Vogel-Mikuš Katarina Pongrac Paula Likar Matevž Stepic Neva Pelicon Primož Vavpetič Primož Jeromel Luka Regvar Marjana 《Chemosphere》2013
Violets from metal-enriched soils have controversially been described as both heavy-metal accumulators and excluders in the literature. The present study solves the issue for violets of the section Melanium (zinc violets, Viola lutea ssp. calaminaria and V. lutea ssp. westfalica; hartsease or wild pansy, Viola tricolor; and mountain pansy, V. lutea). The aims were to determine the concentrations of heavy metals in the soil and in the roots and shoots of field-collected plants, to evaluate the potential impact of colonisation by arbuscular mycorrhizal fungi on heavy-metal concentrations in the plant tissues, and to quantitatively define the localisation of the elements in root cross-sections. When these violets grow in low-metal soils, higher concentrations of the heavy metals were found in the roots and shoots than in the soil, whereas the opposite was seen in samples from high-metal soils. Under all field conditions examined, the roots of all of these species were colonised by arbuscular mycorrhizal fungi. However, V. tricolor was marginally colonised when the concentrations of Zn and P were higher in the soil. Determination of the spatial distribution of the elements in root cross-sections of these violets indicates tissue-specific deposition of elements within the vascular tissue, the cortex, and the rhizodermis. These data indicate that violets of the section Melanium are heavy-metal excluders. 相似文献
12.
Vujisić Ljubodrag V. Vučković Ivan M. Makarov Slobodan E. Ilić Bojan S. Antić Dragan Ž. Jadranin Milka B. Todorović Nina M. Mrkić Ivan V. Vajs Vlatka E. Lučić Luka R. Ćurčić Božidar P. M. Mitić Bojan M. 《Die Naturwissenschaften》2013,100(9):861-870
The Science of Nature - The geophilomorph centipede, Himantarium gabrielis, when disturbed, discharges a viscous and proteinaceous secretion from the sternal glands. This exudate was found by gas... 相似文献
13.
Luka Kuol 《Disasters》2019,43(Z1):S28-S35
Past disasters have been well studied, but the challenge of using the findings to improve the management of future events remains a daunting task. This paper argues that there are new and complex disasters of which the state itself has become the main source, as reflected in the Horn of Africa. This region is characterised by increasing vulnerability owing to the alarming decline of democracy and the rise of authoritarianism. These new disasters are less researched because of the hazard of conducting fieldwork in such environments. However, there is mounting evidence to highlight the possibility of performing research in these settings, but not by employing traditional methods; rather, these tools may need to be customised for use. One key policy implication here is that donors may need to invest more money in analysing these new disasters and they may need to consider building and strengthening genuine partnerships between Northern and Southern research institutions 相似文献