Traditional elderflower beverages are very popular due to their pleasing taste and pro-health properties. Phenolics were quantified in three elderflower extracts (methanolic extraction and two water extracts prepared as fresh drinks according to local recipes) with HPLC-MS. Chromatographic patterns of methanolic and water extracts were quite similar; however, content levels of individual compounds differed between the two extraction solvents. Two feruloylquinic acids and two p-coumaroyl-caffeoylquinic acids and different flavonol glycosides have been identified in elderflowers for the first time. Hydroxycinnamic acids and flavonol glycosides were the major phenolic constituents in elderflowers. Methanolic extract contained higher levels of all phenolic groups compared to water-extracted samples. The yield of elderflower extracts depended on extract solution and time of extraction. Elderflower beverages were characterized by high total phenolic content (91.09 to 746.63 mg GAE/L). The results confirmed that elderflower beverages (sabesa, syrup) should be recommended as a good source of phenolics in human diet.

The phenomenon of increased temperature in cities compared to their rural environs, also referred to as urban heat island, is one of the most evident anthropogenic climatic modifications. Introducing green spaces and vegetation is the fastest, simplest, and a highly effective way of mitigating and adapting urban temperature conditions. The primary goal of the presented research is to identify the interrelationship between urban heat island magnitude (UHIM) and urban green infrastructure extent, shape, and distribution on European scale comparing different green space planning traditions -planning families (PFs). The UHIM for the European cities was calculated based on a reconstructed MODIS LST dataset of a period of ten years.The reasons for the arrangement of UHIMs according to PFs and green land use are not easily explained and are certainly influenced by a number of various conditions in different PFs. UHIM increases with the longitude of cities. In some of the PFs, the relation between the UHIM and land use proportion is characteristic for certain land uses, but a considerable difference between PFs regarding land use proportion with significant impact on UHIM can only be noted in case of a forest. The configuration and composition of the forest correlate with UHIM with statistical significance, but the share of the forest does not affect UHI in all PFs in the same way. While a higher proportion of forest, higher largest patch index, higher mean patch area, higher edge density and higher proportional landscape core is associated with a lower UHIM in the New member and Mediterranean PFs, the relationship in other PFs is reversed.Information on general patterns of UHIM occurrence in relation to urban green infrastructure characteristics could help urban planners and politicians introduce changes on the local level, which would help providing nature-based solutions for the mitigation of the UHI phenomenon. 1.

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Intra-annual variations in leaf development, radial growth, including the phloem part, and sap flow have rarely been studied in deciduous trees from drought-prone environments. In order to understand better the chronological order and temporal course of these processes, we monitored leaf phenology, xylem and phloem formation and sap flow in Quercus pubescens from abandoned karst grasslands in Slovenia during the growing season of 2014. We found that the initial earlywood vessel formation started before bud opening at the beginning of April. Buds started to open in the second half of April and full leaf unfolding occurred by the end of May. LAI values increased correspondingly with leaf development. About 28% of xylem and 22% of phloem annual increment were formed by the time of bud break. Initial earlywood vessels were fully lignified and ready for water transport, indicating that they are essential to provide hydraulic conductivity for axial water flow during leaf development. Sap flow became active and increasing contemporarily with leaf development and LAI values. Similar early spring patterns of xylem sap flow and LAI denoted that water transport in oaks broadly followed canopy leaf area development. In the initial 3 weeks of radial growth, phloem growth preceded that of xylem, indicating its priority over xylem at the beginning of the growing season. This may be related to the fact that after bud break, the developing foliage is a very large sink for carbohydrates but, at the same time, represents a small transpirational area. Whether the interdependence of the chronological sequence of the studied processes is fixed in Q. pubescens needs to be confirmed with more data and several years of analyses, although the ‘correct sequence’ of processes is essential for synchronized plant performance and response to environmental stress.

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