Water suppliers should provide safe drinking water following preventive measures. This is especially important for karst water sources, as they are among the most vulnerable. Recently, there has been a strong focus on the early warning system, which mainly involves monitoring proxy parameters, but does not consider drainage area conditions and other monitoring recommendations. Here, we present an innovative strategy for assessing contamination risk of karst water sources that covers spatio-temporal dimensions and can be integrated into management practices. It is based on event-based monitoring and risk mapping and has been tested in a well-known study area. The holistic early warning system provides accurate spatial hazard and risk assessment and operational monitoring guidelines, including locations, indicator parameters, and temporal resolution and duration. In the study area, the high contamination risk, representing 0.5 % of the area, was spatially delineated. The highest probability of source contamination occurs during recharge events when proxy parameters such as bacteria, ATP, Cl, and Ca/Mg ratio should be monitored in addition to continuous monitoring of turbidity, EC, and T. Monitoring of sinking streams should serve as a preventive measure, since water transfer from ponors to springs has been shown to take about one day, and poor quality water is present for at least another day. Therefore, intensive monitoring should be conducted at intervals of a few hours for at least a week. Although hydrologic systems vary, the proposed strategy is particularly useful in systems where water flows rapidly and where remediation is not feasible.

Various multivariate statistical techniques (MST) can provide valuable insights into water quality variability. Despite numerous studies in which these methods have been used, their potential has not been fully exploited. This paper presents an improved approach to better understand the hydrodynamics of karst systems. The integrated application of hierarchical cluster and principal component analysis in combination with factor analysis allowed the construction of an advanced multivariate chemograph. The analytical procedure was applied in a binary karst aquifer known for its complex hydrodynamics and mixing of water with similar hydrochemical composition. In addition, the study area provides access to an integral groundwater flow system (ponor‐cave‐spring) and offers extensive prior hydrogeological knowledge. The approach allowed reduction and discrimination of the main parameters affecting water quality characteristics. Their identification enabled recognition of three predominant recharge components: (a) stored water impact with Cl and electrical conductivity, (b) sinking stream impact with turbidity and bacteria composition and (c) karst aquifer impact with Ca/Mg ratio as principal parameters. The results supported innovative characterization of the dominant processes and isolation of temporal hydrodynamic phases of individual monitoring points within the aquifer system. On this basis, a spatio‐temporal conceptual model was developed and the hydrodynamic behavior of the main springs was revealed. The applied methodology demonstrated to be useful in ascertaining functioning of a complex karst system under flood event conditions.

The karst environment presents a special challenge when it comes to identifying groundwater/surface-water interactions. Existing definitions of areas of regular flooding in karst regions are too general and lack a measurable approach for the determination of flood-liable land. This paper proposes a means of specific definition and quantitative determination of intermittently flooded karst areas, which takes into account the extent, duration and frequency of flooding, and includes the identification of data sources and processing methods. The procedure, involving spatial layers, was developed using a pilot area and tested in three additional areas in Slovenia. The derived definition determines that flood-liable land within karst poljes and intermittent lakes comprise areas where stagnant water or stream overflow is present for at least 10 days/year over a period of 30 years, and these waters have direct contact with groundwater. The results show that the proposed procedure is applicable to areas with different geomorphological settings and to areas where the quantity and quality of available data vary. The study is an example of the practical application of knowledge on karst, as the findings can be used for short-term purposes (mapping flood areas, determination of habitats) and long-term purposes (study of impacts of environmental changes). Attention should be drawn to the lack of available data and the fact that the national networks of hydrological observatories are often too sparse for this purpose. This study raises awareness of these shortcomings and improves the planning or expansion of such a network in collaboration with experts.

Study Region: Cerkniško Polje, (SW Slovenia) - regularly flooded polje with a complex recharge and partly disturbed due to human interventions. Study Focus: We focus on the long-term flooding dynamics on the polje, including analyses of trends over time, seasonal changes and identification of the impact of climate change and human construction activities on the flooding dynamics. For this purpose, we used a 70 years long dataset of continuous hydrological and meteorological measurements, and analysed documents about past human activities on the polje. New Hydrological Insights for the Region: Comprehensive analyses have revealed notable changes in the flood dynamics over past decades which mostly reflect a general drop of the water level. This is linked to both changes in the climate (lower effective precipitation) and human construction activities (regulation of the river beds, construction of dams, widening or reclogging of swallow holes). In the 1970s floods were longer and more extensive due to experimental permanent lake formation but since the partial removal of constructions, floods have become shorter and less extensive, although extreme events are more frequent than in the past. These changing patterns further impact on biodiversity, which is one of the most remarkable elements of the polje.

The book (‘Geography and plant succession. Selected examples from Slovene regions’) is dealing with ecological succession which is one of three kinds of changes in vegetation. The other two are regeneration (or the result of necrosis and regrowth of organisms) and fluctuation (or changes in biomass in longer and shorter time cycles–also seasonal changes). Ecological succession or ecological sequence can be understood as a temporal-spatial clarification of the evolutionary development of a community from bare soil to a stable community which is balanced with its environment. The book is divided in two parts. In the first part, succession is presented on a theoretical basis. The development of the concept of succession through history, its mechanisms and processes carried on in it are clarified. Different types of succession as well as pioneer species and climax societies as the starting and final point of the process under consideration are described. In separated chapters, invasive species and soils as well as their role in succession are discussed. In the second part, individual selected environments (gravel pits in rivers, screes, rockfall areas, fire areas and construction pits) where the two major types of succession are prevailing are presented.