Direct and indirect trophic interactions of <Emphasis Type="Italic">Aurelia </Emphasis>sp. (Scyphozoa) in a stratified marine environment (Mljet Lakes,Adriatic Sea)

The pattern of diel vertical migration and the trophic interactions of moon jelly (Aurelia sp.) were investigated in the sea lakes of Mljet Island (Adriatic Sea) where this scyphomedusa is present throughout the year. Water column characteristics, plankton and in situ behaviour of Aurelia were followed over several 24-h cycles (6–8 times during each cycle) from the surface to the bottom (44 m). Aurelia exhibited a consistent pattern of diel vertical migration. Most of the time Aurelia were located at the bottom of the thermocline layer at temperatures lower than 19°C. Aurelia migrated towards the surface at dusk when the majority was found within the thermocline or just above it. During the night the medusae sank into the deepest layers below 25 m. The main medusa food items inferred from stomach contents were small adult copepods like Oithona nana and Paracalanus parvus and copepodites of small calanoids and cyclopids. In addition, in situ feeding experiments indicated high clearance rates for nauplii and naked ciliates and clear response of bacterial populations pointing to indirect cascade effects of Aurelia on microbial in addition to classical food web.     

Modelling spatial distribution of the Croatian marine benthic habitats

Within the framework of the 3-year project “Mapping the habitats of the Republic of Croatia” the marine benthic habitats of the entire Croatian maritory were mapped. The supralittoral and the mediolittoral were mapped as a function of the coastal lithology and the presumed levels of human impact (both in scale of 1:100,000). The infralittoral was mapped on the basis of spatial modelling (using neural networks as a modelling tool, data about habitats collected by fieldwork as the independent variable for training and testing the model, and the digital bathymetrical model, the distance from coast, the second spectral channel of Landsat ETM+ satellite image and the sea bottom sea temperature, salinity and current magnitude, as dependent variables). The circalittoral and the bathyal were mapped by overlapping and reinterpretation of the existing spatial databases (bathymetry and lithology) within the framework of the raster-GIS.     

Diurnal vertical migration of Solmissus albescens (Hydromedusae) in the Southern Adriatic

During a study on diurnal vertical migration in the hydromedusa Solmissus albescens (Gegenbaur, 1856), 112 net samples were taken from a depth of 1000 m to the surface. Sampling was performed in July, August, and September, 1969, at a station located 20 miles SSW of Dubrovnik (Yugoslavia). S. albescens migrates vertical distances of over 300 m. No significant influences on migration were noticed due to environmental factors (temperature, salinity, vertical water currents, etc.). The hydromedusa was able to approach surface layers. The recording obtained at various water-depth levels are considered in relation to illumination, mechanisms of evolution, and feeding of S. albescens.     

Study of personal exposure to airborne respirable particles and carbon monoxide

Simultaneous measurements of CO and respirable particles (RP) at outdoor network stations and of personal exposure in a sample of twelve volunteers were carried out during the winter and summer season of 1980/81 in order to evaluate how well personal exposure can be assessed from outdoor network station data.The results have shown that personal exposure of our subjects to both CO and RP is in best correlation with exposure at home where subjects spend in the average nearly 70% of their time. While personal exposure to CO can hardly be related to outdoor CO levels, personal exposure to RP is in fair agreement with simultaneously measured outdoor concentrations in winter (but not in summer). A large intercept on WAE axis of the WAE/RP relationship indicates that a considerable part of personal exposure to RP should be attributed to particles which are not of indoor origin. This part does not follow the seasonal and day-to-day changes in outdoor RP concentration and causes a negative, but highly significant correlation between WAE/RP ratio and RP.     

Whole genome amplification and microsatellite genotyping of herbarium DNA revealed the identity of an ancient grapevine cultivar

Reconstruction of the grapevine cultivation history has advanced tremendously during the last decade. Identification of grapevine cultivars by using microsatellite DNA markers has mostly become a routine. The parentage of several renowned grapevine cultivars, like Cabernet Sauvignon and Chardonnay, has been elucidated. However, the assembly of a complete grapevine genealogy is not yet possible because missing links might no longer be in cultivation or are even extinct. This problem could be overcome by analyzing ancient DNA from grapevine herbarium specimens and other historical remnants of once cultivated varieties. Here, we present the first successful genotyping of a grapevine herbarium specimen and the identification of the corresponding grapevine cultivar. Using a set of nine grapevine microsatellite markers, in combination with a whole genome amplification procedure, we found the 90-year-old Tribidrag herbarium specimen to display the same microsatellite profile as the popular American cultivar Zinfandel. This work, together with information from several historical documents, provides a new clue of Zinfandel cultivation in Croatia as early as the beginning of fifteenth century, under the native name Tribidrag. Moreover, it emphasizes substantial information potential of existing grapevine and other herbarium collections worldwide.     

Traces of DU in samples of environmental bio-monitors (non-flowering plants, fungi) and soil from target sites of the Western Balkan region

This paper reports results of gamma and alpha spectrometric measurements for mosses, lichens, fungi and soil samples from areas in the Balkans targeted by depleted uranium (DU). Samples were collected in 2002 and 2003 in the vicinity of several villages, principally Han Pijesak (Bosnia and Herzegovina, hit by DU in 1995) and Bratoselce (South Serbia, hit by DU in 1999) and in lesser numbers from Gornja Stubla, Kosovo (which is identified as a high natural radon/thoron area) and Presevo close to the Kosovo border. In the course of gamma spectrometric measurements some results suggested samples with unusual high uranium contents which might be considered to be a signature for the presence of DU, although many samples had very high detection limits. Alpha spectrometric measurements directly proved the presence of DU for five samples, all from directly targeted places. These were samples of mosses, lichens and soil. For some samples homogeneity tests were applied which showed a rather even distribution of DU in these samples. No trace of DU was found in any sample from a dwelling.     

Major histocompatibility complex class II variation in bottlenose dolphin from Adriatic Sea: inferences about the extent of balancing selection

The bottlenose dolphin (Tursiops truncatus) is the most common cetacean species worldwide and the only marine mammal species resident in the Croatian part of the Adriatic Sea. To gain insight into genetic diversity of bottlenose dolphins at adaptively important loci relevant to conservation, we analysed the polymorphism of major histocompatibility complex (MHC) genes, which play a key role in pathogen confrontation and clearance. Specifically, we examined the diversity of MHC class II DRA, DQA and DQB alleles in 50 bottlenose dolphins from the Adriatic Sea collected between 1997 and 2011 and in 12 animals from other Mediterranean locations. Notable variation in DQA, DQB and three-locus haplotypes was found, with all 10 DQA and 12 DQB alleles encoding unique protein products. Analysis of the ratio of non-synonymous to synonymous substitution rates suggests that positive selection acts at both highly variable loci. Phylogenetic analyses revealed trans-species polymorphism at the DQB locus, strongly indicating the influence of balancing selection in the long term. In fact, the balancing selection observed in bottlenose dolphins is higher than that reported for most other cetaceans and comparable to that seen in terrestrial mammals.     

The regulation of a spatially heterogeneous externality: Tradable groundwater permits to protect streams

Groundwater pumping can reduce the flow of surface water in nearby streams. In the United States, recent awareness of this externality has led to intra- and inter-state conflict and rapidly-changing water management policies and institutions. Although the marginal damage of groundwater use on stream flows depends crucially on the location of pumping relative to streams, current regulations are generally uniform over space. We use a population data set of irrigation wells in the Nebraska portion of the Republican River Basin to analyze whether adopting spatially differentiated groundwater pumping regulations leads to significant reductions in farmer abatement costs and costs from damage to streams. We find that regulators can generate most of the potential savings in total social costs without accounting for spatial heterogeneity. However, if regulators need to increase the protection of streams significantly from current levels, spatially differentiated policies will yield sizable cost savings.