In this survey the use of nitrogen stable isotope analyses to investigate the amount of discharge material (mainly municipal sewages) along the Istrian coast were presented. The purposes of study were (1) to measure nitrogen isotope composition of Patella sp. as a potential bioindicator for tracing anthropogenic pollution in the coastal marine environment and (2) to detect possible isotopic variations between limpets of different size or between different organism tissues. The results indicated generally significant variations of δ15N between sampling sites. And suggest that the limpet is a useful indicator for tracing anthropogenically derived organic matter from coastal areas in marine ecosystem. Lower δ15N values were measured in impacted areas, while at potentially polluted sites the δ15N enrichment was observed. Significantly lower δ15N values were observed near larger town where a well regulated purification plant system was working and remove undesirable substances (i.e. nitrates) from sewage. Relatively small increases in δ15N values were observed in larger limpet individuals that suggest a rather uniform diet in limpets over the organism’s size spectrum.
COBISS.SI-ID: 1072478
The aim of this research was to determine how best to utilize two environmentally challenging types of waste: sewage sludge, and a particular type of waste ash, biomass ash, which is obtained from biomass combustion processes. The results of the performed research have shown that liquid sewagesludge can, in fact, be successfully stabilized with biomass ash, so that a stable composite material can be obtained, having a compressive strength within the range between 0.5 to 2.5 MPa, with "Controlled Low-Strength Material" properties. During the stabilization process, the microbial activity of sewage sludge is inhibited, due to raised pH levels and temperatures. Analysis of the chemical composition of water leachates from samples of the composite showed that it is inert, and thus does not pose a threat to the environment. From the point of view of sustainable development, this kind of waste management presents an optimum - zero waste solution, since it results in the cleaner production, while preserving natural resources, reducing CO2 emissions, and lowering the costs of sewage sludge management.
COBISS.SI-ID: 1998695
The role of aquaculture activity as a source of selected metals was analyzed within this study. Significant differences in element content between cultured (Dicentrarchus labrax, Sparus aurata) and wild fishes as well as between fish muscle and their feed were detected. Generally mean concentrations of trace elements in all fishes are below the prmissible levels. Significant diferences were observed between sampling sites (wild specimens) as well as fish size (cultured specimens). The majority of metal concentrations in commercial fishes showed no problems for human consumption.
COBISS.SI-ID: 1038174
The analysis of high resolution airborne lidar topography represents an essential tool for the geomorphological investigation of surface features. Here we present a detailed lidar-based geomorphological analysis of the ravines cut into the slopes of the upper Vipava valley, NW Slovenia. The NE slopes are defined by an Oligocene thrustfront ofMesozoic carbonates overthrusted on Tertiary flysch and covered by numerous fan-shaped Quaternary gravity flows, deposited in palaeo-ravines cut into the flysch base rock. In contrast, the opposite SWslopes are composed solely of flysch. The large dextral-slip Vipava fault extending in theNW–SE direction is present in the central part of the valley. Our research revealed that although the ravines on both slopes of the Vipava valley are lithologically and tectonically controlled, significant statistical differences in their directions exist. Thus, ravines on opposite slopes are not solely related to the Vipava fault system deformation, but instead reflect a more complex tectonic setting. We believe that the ravines are controlled by second-order faults and fault zones that connect the Vipava fault with adjacent faults. On theSWslopes, these include connecting faults between the Vipava and the southwestern Raša fault, with the ravines on the NE slopes formed in fault zones connecting the Vipava and northeastern Predjama faults.
COBISS.SI-ID: 36068141
The water vapour permeability of concretes or various building systems is an important parameter when defining the concept of favourable living conditions.Within the scope of the research described in this paper, the watervapour permeability of concretes prepared with different lightweight aggregates (LWA) having an open porosity was compared with that of concretes made with a selected ordinary aggregate. It was found that the coefficient of water vapour permeability l was, in the case of all the investigated concrete prepared by lightweight aggregates and used water/cement factors, less than 35, whereas in the case of the ordinary concrete it amounted to 84. It is interesting to note that SEM investigations of the interface (transition) zonebetween the aggregates and the cement matrix did not indicate the occurrence of any densification which could have a negative effect on the water vapour permeability of lightweight concretes (LWAC).
COBISS.SI-ID: 2055271