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Opis: The presence of the least adder's tongue (Ophioglossum lusitanicum) in Croatia is sparsely documented in scientific literature, with only a few records to date. After findings from the 19th century, the species was not confirmed in the field for a whole century, and was consequently considered extinct in the Croatian flora. It has been recently confirmed in southern Istria (Croatia), in habitats with moderate anthropogenic impacts.
Ključne besede: Croatia, distribution, endangered species, flora, Istria, Ophioglossum lusitanicum
Objavljeno v DKUM: 28.03.2017; Ogledov: 1018; Prenosov: 400
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Ključne besede: Cucurbita pepo, Styrian oil pumpkin, Zucchini yellow mosaic virus, reactive oxygen species, systemic acquired resistance, glutathione, L-2-oxothiazolidine-4-carboxylic acid, salicylic acid, somatic embryogenesis, virus tolerance
Objavljeno v DKUM: 10.07.2015; Ogledov: 1106; Prenosov: 34
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Opis: In the present study, we investigated the species richness and species composition in relation to light and management regime in remnants of wooded meadows within the riparian forests along the middle Drava River in Slovenia. 41 plots of still managed and, at different time periods (<5 yrs, 5-15 yrs, >15 yrs), abandoned riparian wooded meadows (RWM) were sampled. In addition to vegetation relevés, light intensity (PAR) was also measured in plots. Within the still-managed RWM, two floristically distinct types were recognized using TWINSPAN analysis: meadow-like and forest-like. Light intensity differed significantly between types. The CCA of active RWM showed a significant relation between species composition and light conditions. The number of species per relevé on active RWM was negatively correlated with light intensity - in contrast to North European wooded grasslands. This could be explained by the influence of species-rich riparian hornbeam forests that contribute many understorey species, in contrast to naturally mesotrophic meadows. CCA of both active and abandoned RWM demonstrated that light was a good predictor of RWM species composition and that abandonment caused profound changes in floristic composition. The species turnover during succession was more pronounced in less shaded meadow-like RWM where more light-requiring (grassland) species occurred. Species richness was the highest in active forest-like RWM. There were no significant differences in species richness between active meadow-like RWM and groups of abandoned RWM. The remains of riparian forests stretching along the flood plains of Central and Eastern Europe are considered one of the most natural ecosystems in the prevailing agricultural landscape. But naturalness could be in many cases only the consequence of abandonment of ancient land-use practices, like grazing of livestock, cutting between the trees, litter collecting, etc. Examination of the middle Drava River in Slovenia suggests the need to recognize the remains of ancient cultural landscape.
Ključne besede: botany, meadows, wooded meadows, Drava river, species richness, abandonment
Objavljeno v DKUM: 07.06.2012; Ogledov: 1485; Prenosov: 67
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Opis: The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817 kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150 W of acoustic power and within the 5-300 mgžL initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6 h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6 h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone.
Ključne besede: textile industry, wastewater treatment, textile dyeing, reactive dyes, azo dyes, decoloration, ultrasound, degradation, decoloration kinetics, oxidizing species
Objavljeno v DKUM: 01.06.2012; Ogledov: 1896; Prenosov: 91
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