Gorazd Urbanič

Learn More
The intercalibration (IC) exercise is a key element in the implementation of the Water Framework Directive (WFD) in Europe. Its focus lies on the harmonization of national classification methods to guarantee a common understanding of ‘Good Ecological Status’ in surface waters. This article defines reference conditions and sets class boundaries for deep(More)
Legislation in Europe has been adopted to determine and improve the ecological integrity of inland and coastal waters. Assessment is based on four biotic groups, including benthic macroinvertebrate communities. For lakes, benthic invertebrates have been recognized as one of the most difficult organism groups to use in ecological assessment, and hitherto(More)
The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference(More)
The relationship between caddisfly assemblage structure and four selected environmental variables (substrate, water depth, flow type and amount of the coarse particulate organic matter) was investigated in a Slovenian lowland stream. Caddisflies were sampled at four stream reaches according to selected microhabitat types. All together, 168 quantitative(More)
We investigated the effect of different subsample fractions on the variability of benthic invertebrate metrics. The results of six fractions 1/12, 1/6, 1/4, 1/3, 5/12 and 1/2 were compared to the results of the whole samples. Over 120 metrics were tested using five datasets: ecoregion Alps and four river types. In general, variability of metrics decreased(More)
Eleven European countries participated in an exercise to harmonise diatom-based methods used for status assessment in lakes. Lakes were divided into low, medium and high alkalinity types for this exercise. However, it was not possible to perform a full intercalibration on low alkalinity lakes due to the short gradient and confounding factors. Values of the(More)
The European Water Framework Directive establishes a framework for the protection of water resources. However, common water management tools demand common understanding of assessment methods, so quality goals are equally met. Intercalibration of methods ensures the comparability of biological elements across similar geographical areas. Many aspects can(More)
The concept of "reference conditions" describes the benchmark against which current conditions are compared when assessing the status of water bodies. In this paper we focus on the establishment of reference conditions for European lakes according to a phytoplankton biomass indicator--the concentration of chlorophyll-a. A mostly spatial approach (selection(More)
Within the Mediterranean region each country has its own assessment method based on aquatic macroinvertebrates. However, independently of the classification system, quality assessments should be comparable across members of the European Commission, which means, among others, that the boundaries between classes should not deviate significantly. Here we check(More)
Studying human impacts on riverine systems is challenging due to the natural diversity and multiple stressors that are co-occurring. The term stressor(s) refers to variable(s) of anthropogenic landscape changes and local abiotic stream conditions that reflect human activities. We compared the effects of different stressors and natural (typology) factors on(More)