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The paper reports a morphological study of fruits and seeds of Ruscus hypoglossum L., a species interesting as an ornamental plant. Initially, the length, width and weight of fruits as well as seeds were measured in 14 natural populations growing in Croatia. The length/width ratios of fruits and seeds were calculated, as well as the fruit/seed ratios of length, width and weight. Interannual differences in the analyzed traits over three years were compared in two populations. The most promising populations for further selection for ornamental use were the Bilogora population with the largest fruits (length 12.30 mm, width 11.56 mm, weight 0.75 g) and the Strahinščica population with the roundest fruits (length/width 1.04). The average number of seeds per fruit for the populations was 1.40. Variability between the three years was minor for fruit traits but significant for seed traits.
Global climate change is predicted to alter growing season rainfall patterns, potentially reducing total amounts of growing season precipitation and redistributing rainfall into fewer but larger individual events. Such changes may affect numerous soil, plant, and ecosystem properties in grasslands and ultimately impact their productivity and biological diversity. A five-year field study with regulated amount of precipitation was executed in different types of temperate grasslands (dry Festuca, wet Cirsium and Nardus grasslands) in three different regions (in lowland, highland and mountain, respectively) in the Czech Republic. Three simulated rainfall treatments were applied: reduced rainfall by 50% (dry), increased rainfall by 50% (wet), and natural rainfall of the current growing season (ambient). The addition of supplemental resources of water exhibited slightly positive relation with the above-ground production (AP), but statistically significant only in the lowland grassland. At all grasslands, both root biomass (RB) and total below-ground biomass (TBB) were significantly higher in wet compared to dry treatments. Significantly increased values of the TBB/AP ratios occurred only in the highland grassland due to enhanced rainfall. The opposite relations were found in lowland grassland where the TBB/AP ratio decreased in response to enhanced rainfall, though not significantly. In the mountain grassland, values of the TBB/AP ratios have shown less variability. The highland wet Cirsium grassland was more sensitive to altered rainfall regimes forming rather lower proportion of below-ground plant production.
Available CTD profiles from the Gulf of Riga (May—August, 1993—2012) were analyzed to study inter-annual and long-term changes in temperature, salinity and density in relation to river runoff and atmospheric forcing (e.g. Baltic Sea Index). To describe temporal changes in vertical stratification, the upper mixed layer (UML) and deep layer (DL) parameters were estimated. On average the UML depth increases from 8.7 m in May to 9.0, 11.5 and 13.7 m in June, July and August, respectively, and the UML temperature increases from 8.08C to 12.5, 18.7 and 18.68C (May, June, July and August) while the UML salinity increases from 4.90 g kg1 to 5.14, 5.28 and 5.38 g kg1, respectively. High correlation (r = 0.82) was found between the inter-annual changes in river runoff (spring) and mean salinity in the UML in August as well as between DL mean salinity (r = 0.88) and density (r = 0.84) in the Irbe Strait and DL mean salinity and density in the Gulf of Riga. Inter-annual changes in the UML depth as well as in DL salinity and density had a significant correlation with the changes in Baltic Sea Index. The strongest stratification (August) can be observed in the years with the highest UML temperature and the highest river run-off in spring. We suggest that the predicted increase in water temperature and changes in river run-off due to the climate change would result in faster development of the seasonal thermocline in spring and stronger vertical stratification in summer.
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