Assessing Climate Change and Land-Use Impacts on Drinking Water Resources in Karstic Catchments (Southern Croatia)

The Mediterranean freshwater resources, mostly represented by groundwater, are under increasing pressure due to natural and anthropogenic factors. In this study, we investigated possible negative effects of climate change and land-use practices on water quality and availability from five springs in the karstic catchments in southern Croatia. The investigated springs are used in the regional public water supply system. Firstly, we employed hydrogeochemical field and laboratory analyses to detect possible traces of anthropogenic activity originating from specific land use. Additionally, we performed hydrological and climate modeling to detect changes in the air temperature, precipitation, and runoff. In particular, we used three regional climate models (Aladin, RegCM3, and Promes). The results estimated an increase in the mean annual air temperature, changes in the precipitation patterns, and reductions in runoff in the study area. Hydrochemical analyses showed standard ion concentrations for karst groundwaters, elevated sulfates due to evaporite deposits in the hinterland, surprisingly low nitrate levels which disproved expected agricultural pollution, and high microbiological activity. Significant water losses are expected in the near future which require immediate attention in order to develop adaptation strategies that focus on sustainable utilization and resilience of freshwater resources. This paper was based on the Interreg Central Europe PROLINE-CE project research in the South Dalmatia.

Structural and Elemental Analysis of the Freshwater, Low-Mg Calcite Coralline Alga Pneophyllum cetinaensis

Coralline algae are one of the most diversified groups of red algae and represent a major component of marine benthic habitats from the poles to the tropics. This group was believed to be exclusively marine until 2016, when the first freshwater coralline algae Pneophyllum cetinaensis was discovered in the Cetina River, southern Croatia. While several studies investigated the element compositions of marine coralline algal thalli, no information is yet available for the freshwater species. Using XRD, LA-ICP-MS and nano indentation, this study presents the first living low-Mg calcite coralline algae with Mg concentrations ten times lower than is common for the average marine species. Despite the lower Mg concentrations, hardness and elastic modulus (1.71 ± 1.58 GPa and 29.7 ± 18.0 GPa, respectively) are in the same range as other marine coralline algae, possibly due to other biogenic impurities. When compared to marine species, Ba/Ca values were unusually low, even though Ba concentrations are generally higher in rivers than in seawater. These low values might be linked to different physical and chemical characteristics of the Cetina River.

First inventory of vascular flora of Matokit mountain (Biokovo massif, Croatia)

The vascular flora of Matokit Mt (Biokovo Massif) in southern Croatia was researched in different vegetation periods from 2010-2015, and a total of 604 vascular plant taxa belonging to 86 families and 337 genera were found. The studied area has never been studied in the past and these are the first detailed floristic data about grasslands in different succession stages of Matokit Mt. Collected herbarium specimens (345 sheets) were digitalized and are available at the ZAGR Virtual Herbarium. The most dominant families were legumes (Fabaceae 9.9%), grasses (Poaceae 9.1%), daisies (Asteraceae 7.4%) and mints (Lamiaceae 6.8%). The analysis of life forms shows the dominance of hemicryptophytes (39.9%) and therophytes (26.2%) on Matokit Mt that indicates a high influence of the Mediterranean climate. A total of 36 endangered and 17 invasive plant taxa across the whole studied area were recorded. Endemic are 32 plant taxa (26 endemics in a broader sense and 6 stenoendemics) and they represent new site of Croatian flora. The occurrence of some very rare endemics (Cardamine fialae Fritsch and Erysimum croaticum Polatschek) in the flora of Matokit Mt is of special interest for the national flora.

Prospective Analysis of Levels and Correlates of Physical Activity during COVID-19 Pandemic and Imposed Rules of Social Distancing; Gender Specific Study among Adolescents from Southern Croatia

Background: Due to the COVID-19 pandemic, global authorities have imposed rules of social distancing that directly influence overall physical activity in populations. The aim of this study was to evaluate the trends of changes in physical-activity levels (PALs) in adolescents and factors that may be associated with PALs among the studied boys and girls. Methods: Participants in this prospective study comprised 388 adolescents (126 females; mean age: 16.4 ± 1.9 years) from southern Croatia who were tested at a baseline (before the imposed rules of social distancing) and at a follow-up measurement (three weeks after the initiation). Baseline testing included anthropometric variables, variables of fitness status (done at the beginning of the school year), and PALs. At the follow-up, participants were tested on PALs. PALs were evaluated over an online platform using the Physical Activity Questionnaire for Adolescents. Results: A significant decrease of PALs was evidenced for the total sample (t-test = 3.46, p < 0.001), which was primarily influenced by a significant decrease of PALs in boys (t-test = 5.15, p < 0.001). The fitness status (jumping capacity, abdominal strength, aerobic endurance, and anaerobic endurance) was systematically positively correlated with PALs at the baseline and follow-up among boys and girls, with the most evident association between aerobic and anaerobic endurance capacities and PALs. Correlations between anthropometric and fitness variables with changes in physical activity (e.g., the difference between baseline and follow-up PALs) were negligible. Conclusions: Differences in PAL changes between genders were probably related to the fact that PALs among boys were mostly related to participation in organized sports. Correlations between baseline fitness status and PALs indicated the importance of overall physical literacy in preserving PALs in challenging circumstances, such as the COVID-19 pandemic observed here.

Diversity of plant-eating invertebrates as potential prey of carabid beetles in olive groves and vineyards in southern Croatia

Predatory arthropods, among them carabid beetles (fam. Carabidae), play a key role in regulating the plant eating invertebrates in different agroecosystems. Croatian part of Mediterranean is extremely reach in biodiversity, and poorly investigated. Especially, studies on impact of different agricultural practices and use of various pesticides on diversity of beneficial predatory fauna and their trophic interactions have been scarce. Prior to molecular trophic analyses, we sampled invertebrate fauna, as a potential food for predatory arthropods, including carabid beetles, in olive groves and vineyards, both in ecological (EPM) and integrated (IPM) productions, and in pristine natural habitat, typical for that part of karst area. The knowledge on diversity and phenology of potential prey groups is important for developing molecular assays for detecting consumed species, and for better taxonomic resolution of consumed prey species accessed via DNA metabarcoding analysis of stomach content. During vegetation season in 2018 in hinterland of Zadar county “Ravni Kotari”, in southern Croatia, a survey in the canopy and the ground layer was done using yellow sticky traps Plantella©, beating net, pitfall traps and Tullgren funnels. Diversity indices were calculated for each collecting method and for each type of agroecosystem. Results showed that with betting net at least 16 groups, with Tullgren funnels at least 11 and 8 groups of potential invertebrate prey with yellow sticky trap was found. In olive groves 2 and in vineyards 3 of found plant eating groups, respectively could be economically important for production. Diversity and phenology on sites will be presented and discussed in details. This survey contributes to understanding diversity and phenology of different invertebrate prey groups in Mediterranean agroecosystems that could help in sustaining predatory carabids in the field under different pest control practice. The study was conducted under the project activity of HRZZ – Mediteratri and EU INTERREG CBC Pescar.

The lost and rediscovered holotype of Alyssum austrodalmaticum (Brassicaceae) is in line with the latest taxonomic treatment

Alyssum austrodalmaticum was originally described as an endemic species from southern Croatia. It has been considered a dubious taxon because its holotype specimen got lost and because of the scant information contained in the protologue. To settle the interpretation of the name and its application to other Western Balkan populations, a neotype was recently designated. Soon after, the lost holotype specimen was accidentally rediscovered. It is in agreement with the (now superfluous) neotype and the most recent circumscription of the species. Here we present the holotype, summarize the previous uncertainty surrounding this taxon and list all its herbarium specimens from Croatia and adjacent regions deposited in the herbaria CNHM, ZA, ZAHO and ZAGR.

Vitamin D Status and Analysis of Specific Correlates in Preschool Children: A Cross-Sectional Study in Southern Croatia

Vitamin D deficiency is a globally important problem, particularly in children, but there is a lack of information regarding this deficiency in preschool children from southeastern Europe. This study aimed to establish the levels of 25-hydroxyvitamin D (25(OH)D) and associations of gender, time spent outdoors, physical activity (PA), and body mass index (as predictors) with the 25(OH)D level (outcome) in healthy preschool children. The participants were preschoolers (all 5–6 years of age) from southern Croatia. All the participants were tested during their mandatory medical examination 6–7 months prior to school enrollment. The PA was obtained using the preschool-age physical activity questionnaire (Pre-PAQ), which categorizes PA into five levels (from sedentary to vigorous PA). The prevalence of 25(OH)D deficiency was high: 58% of the children had 25(OH)D levels of <50 nmol/L (deficiency), and an additional 29% had an insufficient level of 25(OH)D (50–75 nmol/L). Boys had higher levels of 25(OH)D than girls. A multinomial regression using 25(OH)D categories as the outcome and a sufficient level (>75 nmol/L) as the reference value identified gender as the only significant predictor of 25(OH)D status, with boys being at lower risk for 25(OH)D deficiency than girls. These results showed a high prevalence of 25(OH)D deficiency in preschoolers from the southern part of Croatia, which is additionally alarming based on the geographical position of the studied region (42° N) and its high number of sunshine hours (>2600 h per year). Future studies examining other potential correlates of 25(OH)D in the region are warranted.