Western Tatra Research Articles

Light pollution in the Tatra National Park

Light pollution in the form of artificial sky glow affects not only the immediate surroundings of the towns that generate it but also more distant areas, including protected regions. This study examines the extent of the impact of the artificial sky glow, originating from Zakopane and the surrounding towns, on the western part of the Tatra National Park (TPN) in Poland. Due to the specific challenges of conducting night measurements in mountainous terrain, the valleys of the Western Tatras– Lejowa, Kościeliska and Chochołowska - were selected for the study. Sky brightness measurements were taken using Sky Quality Meter photometers (type SQM-L) under both cloudless and completely overcast conditions. The results show that in the case of a cloudless sky, the range of sky glow from nearby towns extends approximately 2-2.5 km from the valleys outlets. However, under cloudy conditions, this range increases to approximately 6 km. It was also observed that the ground illumination caused by the brightened sky is significantly lower than that produced by the brightest natural object in the sky, the Moon. Nevertheless, the night sky’s brightness exceeds natural levels, which undoubtedly affects local mountain ecosystems

Spring water resources in the Tatra Mountains

The Tatra Mountains stand out as the wettest and most water-rich region in Poland. Despite this, limited studies addressed this issue, and current knowledge largely relies on data obtained in the mid-20th century, with a substantial lack of current estimates. This study aims to fill this gap by evaluating the contemporary water resources of springs in the Tatra Mountains. The study bases on the most recent hydrological mapping of 1,018 springs. The spring resources were evaluated using parameters such as the number of springs, specific runoff, and crenological index, analysed across different physiographic regions, tectonic units, and altitudinal zones. Our studies showed that the highest number of springs occurs in the Western Tatras (66%) between 1000 and 1400 m a.s.l., especially within the Sub-Tatric unit. Springs with discharges ranging from 0.1–1.0 dm3∙s−1 constitute approximately 70% of all springs but they contribute to only 8.1% of spring water resources. Total spring discharge amounted to 2726 dm3∙s−1 and was higher in the Western Tatras (1982.5 dm3∙s−1 than in the High Tatras (743.5 dm3∙s−1 . The specific runoff amounted to 12.9 dm3∙s−1 m−2 with the highest total runoff at altitudes occupied by the most abundant karst springs (1000–1100 m a.s.l.). The crenological index amounted to 4.8 springs∙km−2 and was higher in the Western Tatras (6.5 springs∙km−2) than in the High Tatras (4.9 springs∙kmup−2) . The analysis revealed that the only five largest karst springs, constituting a mere 0.5% of all springs, account for 65% of spring water resources in the Tatras.

Does the karst spring improve fish abiotic habitat in mountain streams?

Mountain streams constitute challenging habitat for many fish species due to rapid and variable flow, cool temperature, and limited food resources. Groundwaters recharge by karst spring may however mitigate harsh habit conditions of mountain streams providing niches for different fish species. This study aims to assess the suitability of mountain streams, replenished by karst springs, for various fish species like alpine bullhead, European grayling, brown and brook trout. The study was conducted in the Chochołowski Stream in the Western Tatra Mountains, Poland. The assessment of abiotic habitat is based on different characteristics of hydrological and thermal regimes as well as water chemical composition investigated between 01.09.2012 and 31.09.2014. The findings reveal that: 1) downstream variability of habitat abiotic conditions (such as water temperature, flow, water chemical composition) may affect the distribution of fish species, 2) karst springs contribute up to 100% of the stream’s recharge during periods of winter low flow, 3) karstic groundwater reduces the variability and amplitudes of stream water temperature and weaken the periodicity in water temperature associated with daily course of air temperature and solar radiation, 4) groundwaters prevent stream freezing in winter and moderate summer temperatures, 5) increasing mineralisation of water below the spring recharge may positively affect fish distribution. The findings underscore the importance of karst springs in modifying the abiotic conditions of fish habitat in mountain streams.

Estimation of the leaf area index in a decline spruce forest in the Western Tatra Mountains for determination of rainfall interception

Estimation of the leaf area index in a decline spruce forest in the Western Tatra Mountains for determination of rainfall interception

Soil and Sediments in Natural Underground Ecosystems as a Source of Culturable Micromycetes: A Case Study of the Brestovská Cave (Western Tatras, Slovakia)

Soil and sediment host microorganisms are able to survive in extremely resource-limited environments. Therefore, more and more attention is being paid to cave sediments as a reservoir of microbiota. The aim of this study is the speleomycological evaluation of the culturable soil and sediment fungal communities in the Brestovská Cave. To explore the origins of fungi, speleomycological studies were conducted both inside and outside the cave under investigation. Additionally, two incubation temperatures (5 and 24 °C) were used to increase the species spectrum of isolated fungi. To achieve the most accurate species identification, we combined an assessment of morphological characteristics of the isolates with molecular sequencing (ITS, internal transcribed spacer). Twenty different species were found and the most frequent was Penicillium commune, followed by Trichosporiella cerebriformis and Pseudogymnoascus pannorum. To our knowledge, our study has enabled the first identification of fungal species such as Penicillium swiecicki, Cephalotrichum hinnuleum, Cosmpospora berkeleyana, Lecythophora hoffmannii, Ambomucor seriatoinflatus, and Mortierella minutissima in underground sites. Our data showed that the abundance and composition of the fungal community varied between the indoor and outdoor samples and thus from the entrance and less visited sites deeper in the cave.

Streamflow response to catastrophic windthrow and forest recovery in subalpine spruce forest

Windstorms account for about half of forest disturbances in Europe and are considered as drivers of natural regeneration of plant species, accompanied by significant changes in hydrological and soil moisture conditions. Our study aims to identify the effects of deforestation caused by catastrophic windthrow on streamflow characteristics in conjunction with meteorological and soil moisture data. The research was conducted in the headwater catchment (34.4 km2), in the Western Tatra Mountains, Poland. Streamflow characteristics such as average, high, and low flows, coefficient of variability, as well as flashiness of the streamflow (Richard-Baker Flashiness Index) and drought frequency (Standardised Streamflow Index) were calculated in the pre-event (2007–2013) and post-event (2013–2020) periods. The analysis was carried out for calendar months, seasons of the year, as well as for the growing and non-growing seasons. Wavelet Analysis was applied to track the changes in streamflow time series in relation to meteorological conditions (precipitation, air temperature) and remotely sensed soil wetness in the root zone. Principal Components Analysis was applied in order to identify the major drivers of the observed variability. The results revealed increasing low (+14%), average (+8%), and maximum monthly flows (16%) in the post-event period. The most significant increase in low flows (+47%, p<0.1) occurred during snowmelt. The increase in average (+31%, p<0.1) and high flows (+90%, p<0.05) occurred during mid-winter thaws. The frequency of hydrological droughts decreased by up to 36% in the post-event period, despite similar climatic conditions. The flashiness of streamflow increased during mid-winter thaws and rainfall events. The short-scale periodicity in streamflow increased in the post-event period. The results revealed the presence of 3-month periodicity in the root zone soil wetness associated with long-term soil water storage, which decreased after the catastrophic windthrow. Streamflow in the post-event period became strongly coupled with precipitation and root zone soil wetness at short period bands (∼3–16 days) in hydrologically active season. Short-scale correlation between precipitation and streamflow was decreasing with the gradual succession of vegetation.

Preface: DIDFYZ 2023

Searching for more effective ways of educating the young generation in physics means not only reforming the content and methods from the point of view of us creators and teachers, but mainly understanding the object of education, i.e. a young person - a student leaving school. At the same time, social changes are reflected in the structure of society’s needs for education, in the needs of young people, their approach to their environment, to fulfilling their needs and their attitude to global issues. The ability of society to respond to these requirements is determined mainly by the state and level of education. The advancement of knowledge, social relations and the economy depends on it. The main task of educational systems is to convey new knowledge in science to young people, but also to shape their personality. In physics, this role is particularly important, because knowledge of physics determines knowledge in other areas as well. We have been dealing with the issue of the transfer of physical knowledge within the framework of physics teaching theory, or in other words physics didactics, for more than half a century. Over the past 50 years, we have marked a qualitative shift in the theory and practice of this young scientific discipline. The organizers of the DIDFYZ conferences aimed not only to participate in these changes, but to be their initiators and creators. Regular biennial meetings became a platform for the creation of new ideas in the theory of teaching physics, which gradually grew into the internationally recognized DIDFYZ conference.The idea of organizing regular international meetings of physicists who deal with education in physics arose in the seventies of the last century. The Department of Physics of the Constantine the Philosopher University in Nitra took on the organizational role of the aforementioned conference on current problems of education in physics. It first organized a conference called DIDFYZ in 1977 in Bojnice. Other conferences were held in Nitra, in Rackova dolina in the Western Tatras, and since 2019 the venue of conference is held in Terchová (Vrátna dolina) in the beautiful mountain environment of Malá Fatra National Park.The topics of the DIDFYZ conferences over the past 46 years have always had the ambition to deal with the fundamental problems of physics education. They defined urgent problems that need to be solved at a given time (introduction of new teaching technologies, new physical discoveries and the ability to interpret them, problems of worldview, new trends in experiments, personal development, development of skills).The 23rd DIDFYZ 2023 conference entitled “New approaches in physics education for generation Z” set itself the goal of reflecting the characteristics of the educated generation referred to as “Generation Z” and “Alpha” in physics education, in the content, activities and methods used in teaching physics.Our pupils can be understood as consumers of communicated physical knowledge. Our task is to think in more detail about the characteristics of the generation we are addressing when creating physical education. Identifying which generations we are addressing means at the same time knowing how to address them in order to win them over and motivate them to learn about physics. In today’s education, the generations known as “Generation Z” and “Generation Alpha” face us. The correct grasp of their education is the gateway to the successful creation of the future.The organizers and participants of the conference believe that their efforts and the results presented at the conference will not only bring new knowledge about the possibilities of improving the teaching of physics, but will also contribute to a fundamental change in the quality and level of education and, in particular, to an increase in society’s interest in the problems of education and the educational system.Ľubomír Zelenický, Ľubomíra Valovičová, and Anton Trník EditorsList of Committees, International Scientific Committee, Organizing Committee are available in this Pdf.

Jaskinia Lodowa w Ciemniaku (Ice Cave in Ciemniak), Western Tatra, Poland - over a century-long investigations of climate warming-caused degradation of subterranean ice mass

Jaskinia Lodowa w Ciemniaku (Ice Cave in Ciemniak), in the Tatra Mountains (Tatry), is believed to host the largest subterranean ice mass in Poland. It has been known for over a century, however, the onset of its scientific investigations dates back to 1922, when Tadeusz and Stefan Zwoliński mapped it. Since then, it has become one of the best-known caves in Poland. It was described in over a hundred scientific and popular science papers. They include findings of international importance, e.g. works related to radioisotopes, ice-mass balance and age. However, some of the questions asked a century ago are still partly unanswered. One may wonder if they will be delivered before climate warming causes the largest ‘cave glacier’ in Poland to disappear.

Tracing the latest Jurassic–earliest Cretaceous paleoenvironment evolution in swell carbonate facies: a case study of the High-Tatric succession (Central Western Carpathians, Tatra Mts, Poland)

This paper presents an interpretation of sedimentologic, paleomagnetic, and geochemical data collected in the Upper Kimmeridgian–Valanginian carbonates of the Giewont series (Giewont and Mały Giewont sections, High-Tatric succession, Western Tatra Mountains, Poland). The studied succession provides insight into the sedimentary conditions prevailing in the South Tatric Ridge (Tatricum), a submarine elevation located between the Zliechov Basin (Fatricum) and the Vahic (=South Penninic) Ocean. The sedimentary sequence includes micrites, pseudonodular limestones, cyanoid packstones, lithoclastic packstone, and encrinites. The results are discussed with regards to their significance for detrital input, paleoclimate, and paleoproductivity, which in turn are considered in the context of both local and regional paleoenvironmental trends and events. The greatest depositional depths during the latest Kimmeridgian–earliest Tithonian are documented by the occurrence of pseudonodular limestones. A Tithonian shallowing trend is demonstrated via the increasing size and roundness of cyanoids, while the final (?)emergence and erosion in the South Tatric Ridge is documented by earliest Cretaceous disconformities. This process might have been related to both falling sea-level during the major eustatic regressive cycle and tectonic uplift caused by the mutually related (re)activation in the Neotethyan Collision Belt and rifting in the Ligurian-Penninic-Vahic Oceans. The highest lithogenic influx (although still low; max 0.5% of Al content) during the Late Kimmeridgian is considered as associated with relatively humid climate conditions, whereas a subsequent decreasing trend is thought to result from aridification during the latest Kimmeridgian–earliest Tithonian. Ultimately, deposition in the High-Tatric zone was affected by both large-scale environmental perturbations characteristic of the latest Jurassic (climate changes, variations in seawater pH, monsoonal upwelling, lithogenic input, etc.), as well as local sedimentary controls, predominantly the oxygenation state of bottom waters and tectonic movements. Supplementary Material 1

Physicochemical properties of mountain streams in the High and Western Tatras

The aim of this study was to measure the physicochemical properties of 28 mountain streams in Tatra National Park, Slovakia. Sampling sites (119) were selected based on a previous study conducted in 2010. Physical properties (e.g., temperature, conductivity, total dissolved solids, pH, and dissolved oxygen) and chemical components (e.g., nitrogen oxides, ammonia oxides, chloride compounds, and chemical oxygen demand) of the water were determined. Environmental parameters of streams (elevation, slope, aspect, width, depth, flow accumulation, watershed size, bedrock, and presence of mountain lakes) at sampling sites were examined. While comparing results from both periods (2010 and 2017), we found a correlation in data trends, concluding that elevation plays a significant role in almost all investigated parameters. Downstream, streams were more saturated by dissolved solids, CaCO3, and nitrates, increasing the pH level. Despite this well-known trend, we observed significant higher levels of ammonias and chlorides in the alpine zone, especially at sites where higher water temperature and lower values of dissolved oxygen were observed. This occurred in the Eastern Tatras, below mountain lakes, and where watersheds had granite origins. There are indications that denitrification processes were significantly stronger in 2017, but, on the other hand, increased chlorides resulted in stronger inhibition of nitrification processes in alpine zones at sites below mountain lakes.

10Be exposure ages and paleoenvironmental significance of rock glaciers in the Western Tatra Mts., Western Carpathians

Relict rock glaciers are well-preserved features of high-elevated valleys in the Western Tatra Mts., Western Carpathians, but their chronology remained poorly constrained with numerical dating methods. We present the first robust set of 10Be exposure ages for eight rock glaciers with front elevation of 1376–1819 m asl. The results suggest that the rock glaciers stabilized throughout the Weichselian Lateglacial from ∼16.5 ka to 11 ka. This timing is consistent with the period of rock glacier stabilization in European mountain regions, but it extends the age span previously determined for rock glaciers in the Tatra Mts. There are differences between north- and south-facing valleys in the elevation and time of the stabilization of the rock glaciers, which were probably caused by contrasts in potential incoming solar radiation that affected the retreat of former glaciers and the subsequent formation of the rock glaciers. The initiation altitude of ∼1610 and ∼1830 m asl determined for the oldest and youngest dated rock glaciers is generally consistent with previous estimates of the glacier equilibrium line altitude during the Greenland Stadials 2.1 and 1, respectively. However, the lower limit of the rock glaciers is well above regional paleopermafrost features from the same periods, which suggests that rock glaciers may underestimate past permafrost extents and temperature declines disputing their regional validity for paleoenvironmental reconstructions.

Indications of deterioration of the walls of the climbing route on the Niżnie Jasiowe Turnie Peak (Western Tatra Mts.) caused by natural weathering processes and mountaineering activities

Indications of deterioration of the walls of the climbing route on the Niżnie Jasiowe Turnie Peak (Western Tatra Mts.) caused by natural weathering processes and mountaineering activities

Glacial geomorphology and Pleistocene glacier reconstruction in the Demänovská Valley, Low Tatra Mountains, Slovakia

In the Western Carpathians, clear evidence of the Pleistocene glaciations only occurs in two mountain massifs – the Tatra and Low Tatra Mountains. The Low Tatra Mountains (2043 m a.s.l.), contrary to the higher and more strongly glaciated Tatra Mountains (2654 m a.s.l.), have previously been much less attractive for scientific research. Hence, in these mountains, both glacial landforms and chronology, together with a detailed reconstruction of glacier geometry and resulted equilibrium line altitude (ELA), are poorly documented. The aim of this paper is to characterize the glacial relief and reconstruction of geometry and ELA of the Zadná voda glacier in the Demänovská Valley system which belongs to the category of the largest Pleistocene glaciers on the northern slope of the Low Tatra Mountains. The mapping results show that a freshly shaped, massive terminal moraine of maximal ice extent (MIE, likely formed during the global Last Glacial Maximum – LGM) occurs 4.3 km distance down-valley from the glacial cirque backwalls. There is no evidence of deposits from older glaciations beyond the terminal moraine down the valley. The terminal zone of the MIE features a fresh morainic landscape with hummocky topography with kettle hollows and the only known morainic lake in the Low Tatra Mountains – Vrbické pleso. During the MIE, the Zadná voda glacier covered 7 km2 of the area and featured a mean thickness of 48 m. The ELA of this glacier was 1433 m, determined by the area-altitude balance ratio (AABR) 1.6 method, which is a similar value to the LGM ELA calculated in the Western Tatra Mountains. The recessional stages were only recognized in the cirques area, where one or two generations of debris-covered glaciers and rock glaciers mark the final deglaciation of the study area.

Conditions and morphogenetic role of the 2018 and 2021 debris flows in Starorobociański Cirque, Western Tatra Mts.

In this study we used geomorphologic mapping, precipitation analysis and archival photomaps to study debris flows in the Starorobociański Cirque, which were renewed in 2018 and 2021. Debris flow in 2021 was most likely the largest single flow recorded in the Polish Western Tatras in the twenty first century. It reached a length of about 870 m and it covered an area of ​​0.62 to 0.65 ha. We set July 14, 2021, as the date of debris flow initiation and 52.1 mm·d−1 as its threshold value. This is one of the lowest values provided in the literature for such flows in the Western Tatra Mts. On the contrary, debris flow which occurred July 18, 2018 was linked to threshold value of 150.5 mm·d−1. On the basis of former debris flow occurrence as well as precipitation analysis we interpret the appearance of debris flow in 2021 as an effect of short and intense rainfall.

Possibilities and limitations of using iPhone 13 Pro with built-in LiDAR sensor in cave research – on the example of paleoflow analysis in Mylna Cave (Western Tatra Mts, Poland)

The study tested the capabilities of the Apple iPhone 13 Pro device using two measurement techniques, LiDAR (Light Detection and Ranging) and SfM (Structure from Motion), in a cave environment by measuring scallops in Mylna Cave in Western Tatra Mountains. The tested device provides an interesting and inexpensive alternative for cave research using TLS (Terrestrial Land Scanner) type scanners or more expensive MLS (Mobile Laser Scanning) type scanners. The study used a dedicated 3D Scanner App™ application to create two terrain models: LiDAR and SfM. A comparative analysis of the models shows that the SfM model is characterised by greater detail. The results obtained for this model indicate that the scallops measured in Wielki Chodnik passage of Mylna Cave belong to at least two different generations of forms. In the LiDAR method case, the obtained models’ resolution was not precise enough to identify small (&lt;3 cm) scallops. For three LiDAR models, the average length of scallops was 10.32 cm; for three SfM models, it was 5.16 cm. The length of scallops obtained from models allowed for calculating paleoflow velocity and, thus, the flow rate. The average velocity value for LiDAR models was 28.98 cm s−1, and for SfM models – 48.10 cm s−1 and the average flow rate obtained from SfM data was 1.93 m³ s−1. It corresponds well with the today-observed Kościeliski Potok flow rate of 1.7 m³ s−1 according to the 1966–2000 period (Baścik et al. 2014). On the contrary, the average paleoflow rate obtained from the LiDAR model, which is 0.94 m³ s−1, does not match the contemporary flow rate. Based on the asymmetry of scallops, the paleoflow direction was determined. It is consistent with the current direction of the Kościeliski Potok flow. The spatial imaging techniques used with iPhone 13 Pro differ regarding the DEM creation method and model details. It is influenced by parameters related to lighting, distance, scanned surface character and microclimatic conditions of the cave.

Marsupella subemarginata (Gymnomitriaceae, Marchantiophyta) Newly Found in the Carpathians in the Polish and Slovak Tatras

Abstract Marsupella subemarginata Bakalin &amp; Fedosov is a semi-cryptic Eurasian species. Recently, it has been found in the Far East (Kamchatka and Japan) and Swiss Alps, as well as the Giant Mountains (Sudetes, Czech Republic). The plant was also observed in the Carpathians for the first time. A revision of the herbarium collections of M. emarginata (Ehrh.) Dumort. consisting of 102 specimens from the Polish and Slovak Tatra Mountains revealed the occurrence of M. subemarginata at 24 localities, eight of which were in the Polish Tatras. Most of the localities of this species were concentrated in the High Tatras, and only four sites were discovered in the Western Tatras. Marsupella subemarginata has been briefly characterized morphologically and illustrated. The habitat requirements of the species have been described in detail, and the floristic composition of its phytocoenoses has been shown in a phytosociological table consisting of 10 relevés. Marsupella subemarginata is a valuable addition to the liverwort flora of Poland and Slovakia, which currently consist of 241 and 232 species, respectively. Currently, the liverwort flora of the Tatras comprises 195 species, including 185 species in Poland and 186 species in Slovakia.

Motywacja i sposoby nominacji wybranych oronimów rejonu Czerwonych Wierchów w polskiej części Tatr Zachodnich

MOTIVATION AND METHODS OF SELECTING NAMES FOR CHOSEN ORONYMS OF THE CZERWONE WIERCHY AREA IN THE POLISH PART OF THE WESTERN TATRA MOUNTAINS The purpose of this article is to show various ways of expressing the reality which is characteristic of people who have given names of places in the mentioned area. In this article, the attempt was made to reach to the motivational meaning of 207 oronyms from the Czerwone Wierchy area which is located in the Polish part of the Western Tatra Mountains. These names origin from two detailed mountain guides of the Czerwone Wierchy area and they have been assigned to two different groups. The first group is made up of names that have been formed during the onimization process, and the second – of names that have been formed during the transonimization process. Within these groups further subcategories have been distinguished. In this article multipart names were highlighted. They are characterized by complex motivation. The study showed that a large part of the collected names is a group of oronyms, which have been formed during the onimization process with a part of them that origin from other toponyms (77 oronyms). They are localized names and they show a practical approach to the reality. It can be concluded that this feature caused a high popularity of this naming model. In this article, attention has been paid to the necessity of conducting the socio-onomastics survey.

The Jurassic–Cretaceous transition in the High-Tatric succession (Giewont Unit, Western Tatra Mts, Poland): integrated stratigraphy and microfacies

Herein are presented the results of detailed bio- (calcareous dinocysts, calpionellids, foraminifers, saccocomids) and chemostratigraphic (δ13C) studies combined with high-resolution microfacies, rock magnetic and gamma-ray spectrometry (GRS) investigations performed on the upper Kimmeridgian–upper Valanginian carbonates of the Giewont succession (Tatricum, Giewont and Mały Giewont sections, Western Tatra Mountains, Poland). The interval studied covers the contact between the Raptawicka Turnia Limestone (RTL) Fm. and the Wysoka Turnia Limestone (WTL) Fm. Their sedimentary sequence is composed of micrites, pseudonodular limestones, cyanoid packstones, lithoclastic packstone and encrinites. A precise correlation with the previously published Mały Giewont section is ensured by biostratigraphy, rock magnetic and GRS logs. The methodology adopted has enabled the recognition of two stratigraphic discontinuities, approximated here as corresponding to the latest Tithonian–early (late?) Berriasian and the early Valanginian. The hiatuses are evidenced by biostratigraphic data and the microfacies succession as well as by perturbations in isotopic compositions and rock magnetic logs; they are thought to result from a conjunction of tectonic activity and eustatic changes. A modified lithostratigraphic scheme for the Giewont and the Osobita High-Tatric successions is proposed. The top of the RTL Fm. falls in the upper Tithonian, where cyanoid packstones disappear. At the base of the WTL Fm. a new Giewont Member is defined as consisting of a basal lithoclastic packstone and following encrinites.

Rainfall Thresholds of the 2014 Smutná Valley Debris Flow in Western Tatra Mountains, Carpathians, Slovakia

An extensive debris flow occurred, in the Smutná valley, Western Tatra Mts. in Slovakia on 15 May 2014. The aim of this study is to describe the morphology of the observed debris flow and to evaluate the conditions that preceded its formation as well as the previous activity of debris flows on this path. The observed debris flow is among the most extensive ones in terms of morphometric characteristics in the Roháčská valley and its tributaries (e.g., the length of the erosion-accumulation zone of ~600 m, volume &gt;1200 m3). However, compared to previous studies from the Western Tatra Mts., it belongs to the average sized debris flows, or a minor event in terms of the general size classification based on the volume of debris flows. A similarly extensive debris flow was recorded on this track in the early 1970s after which only two additional minor events have been recorded there until 2014. The monthly precipitation totals in the 2013/2014 winter season were low compared to the long-term average. The main triggering factor for debris flow initiation was continuous rainfall that lasted 29 hours resulting in ~120–135 mm of precipitation. Most of the derived global empirical thresholds for debris flow initiation were exceeded as well as rainfall thresholds suggested by the published studies for the Western Tatra Mts.

Assessing discharge periodicity in mountain catchments using classified environmental conditions (Tatra Mountains, Poland)

The periodicity of a river expressed in cycles of various lengths (monthly, seasonal, multiannual) is a result of climatic factors and overlapping environmental conditions within its catchment. In uncontrolled or poorly surveyed catchments, it is very difficult to determine the duration of a stream’s hydrological activity. This is especially relevant for catchments with complicated water circulation in karstic rocks. The present study concerns the small catchment of the Strążyski Potok river located in the area of the Tatra National Park, in the Western Tatras. The observation period covered the 2015 hydrological year, which differed hydrologically from average conditions. This study aims to develop a simple method to explain the processes shaping the mountain stream discharge periodicity. The research employed periodic field observations linked with climatic and non-climatic factors. Environmental conditions were assessed as four classes reflecting their influence on appearance or disappearance of mountain stream water. Class boundaries were the values of quartiles. The degree of correspondence between environmental factors and stream field observations was described via the Index DC (Degree Correspondence Index) approach. Complete correspondence (Index DC =0) was found in 23% catchments, a weak relationship between conditions favouring discharge and actual condition (Index DC= -1, +1) was noted within 11 catchments, while in 9 catchments, no such relationship was found (Index DC = -2, +2). The obtained results indicate a correspondence or lack thereof between the environmental potential of the catchment and its discharge periodicity. The discrepancies between the assessment of the influence of climatic and non-climatic factors and the data collected during field observations provide a basis for more detailed studies. Continuation of these studies based on the proposed classifications will allow for a more complete explanation of water disappearance in river channels and the determination of their short- and long-term discharge periodicity.