Delimitation of Hydrotopes Using the Example of the Polish Tatra Mountains and The Southern Part of Podhale

The analysis yielded 132,845 individual hydrotopes (after generalisation) ranging from 575 m2 to 3.19 km², 3059 potential hydrotope types, and 15 actual types ranging from 0.01 km² (runoff-evapotranspiration [R-E]) to 239.71 km² (evapotranspiration [E]). These types were divided into 10 simple and 5 complex types (Table 2). The built-up area, which is not subject to the analysis of water circulation types in this study, includes 367 individual combinations (28.38 km²).

Figures 8 and 9 show the different hydrotope types in the Polish Tatra Mountains and the southern part of Podhale. The infiltration type is shown for all microregions of the study area. The highest proportion was recorded in the Wierchy Tomanowo-Jamnickie (18.1% of the area), whereas the lowest was observed in the Kotlina Białczańska (0.20% of the area). The large proportion of the infiltration type in the Wierchy Tomanowo-Jamnickie microregion is related to the fact that a significant part of the area is covered by Quaternary formations, primarily rock, fluvial sediments, moraine covers, Albic Podzols (Ochric) and Albic Podzols, Leptic Podzols. In addition, forest and dwarf mountains, pine and grassy vegetation are dominant.

Fig. 8.

Spatial variation of hydrotope types in the study area.

Fig. 9.

Variation in the dominance of hydrotope types in the study area.

The infiltration flood type is found in seven microregions; mainly in the Pogórze Przedtatrzańskie mesoregion (which is mostly in the Pogórze Bukowińskie and Pogórze Gubałowskie microregions, where it accounts for 33.6% and 21.1% of the area, respectively) and in the mesoregion Bruzda Podtatrzańska (mainly in Rów Kościeliski, where it accounts for 17.4% of the area). The smallest share of the analysed type was recorded in Działy Poronińskie (2.1% of the area). The dominance of this type is related to the occurrence of Quaternary formations, i.e., fluvial, fluvial-glacial formations, and forested areas on floodplains.

The runoff type was determined for 24 microregions. The share of the analysed type ranges from 0.001% (Kotlina Orawic) to approximately 35.9% of the area (Pogórze Gubałowskie). The Pogórze Gubałowskie microregion is mainly dominated by formations of Podhale flysch; it is covered by Eutric Cambisols and Dystric Cambisols, which comprise loam and silt loam. A significant proportion of grassland vegetation and agricultural land is observed, and strongly sloping slopes predominate. Thus, the geological structure, soil cover, land cover, and slope gradient determine the dominant runoff type in this area.

The runoff flood type was determined in seven microregions; mainly in the mesoregion of the Pogórze Przedtatrzańskie and in the Pogórze Gubałowskie (36.9% of the area) and Pogórze Bukowińskie (23.8% of the area) microregions. A significant share was also recorded in the Rów Zakopiański (23.8% of the area). The smallest share of this type was recorded in the Magura Witowska microregion (0.01% of area). The occurrence of the analysed type in the area of Pogórze Podtatrzańskie is mainly connected with the occurrence of the Podhale flysch formations, grassy vegetation and the cultivation of arable land in floodplains.

The evapotranspiration type was determined in all microregions, mainly in the mesoregion of the Pogórza Przedtatrzańskie and in the Pogórze Gubałowskie (33.4% of the area), Pogórze Bukowińskie (15.9% of the area), and Pogórze Brzegowskie (8.8% of the area) microregions. The smallest share of this type was recorded in the Masyw Mięguszowiecki microregion (0.03% of area). The dominance of the analysed type is caused by its occurrence in the Pogórze Gubałowskie, mainly in the Podhale flysch formations, including the Eutric Cambisols, Dystric Cambisols, loam, silt loam, grassland vegetation and agricultural land.

The evapotranspiration flood type was determined in seven microregions, mainly in the Pogórza Przedtatrzańskie mesoregion – in the Pogórze Gubałowskie (42.1% of the area), Pogórze Bukowińskie (20.9% of the area), and Pogórze Brzegowskie (8.2% of the area) microregions. A significant share was also recorded in the Rów Zakopiański (16.0% of the area). The smallest share of this type occurs in the Magura Witowska microregion (3.1% of the area). As previously stated, geological structure, soil cover, and land cover clearly influence the dominance of the evapotranspiration type; additionally, due to the occurrence of floodplains, the evapotranspiration flood type could be distinguished.

The retention marsh type occurs in 22 microregions. The highest share of the analysed type was found in the Działy Poronińskie (30.1% of area) and Pogórze Gubałowskie (25.9% of area). The smallest share was recorded in the Tatry Orawicko-Witowskie microregion (0.01% of area). This type is associated with the occurrence of the above-mentioned microregions of permanently and periodically wet areas, peaty soils, marshypeaty soils, mud-peat soils, peat-mud soils, low peats, transitional peats, and high peats.

The retention lake type occurs in 13 microregions. It was found that 78.6% of the area occurs in the microregion – Wierchy Pięciostawiańsko-Białczańskie, which is characterised by numerous lakes. A significant share was also recorded in the Grań Orlej Perci microregion (18.9% of the area). The smallest share of the analysed hydrotope type was found in the Grupa Kop Kop Sołtysich microregion (0.03% of the area).

The trough retention permanent type occurs in all microregions. The proportion of the analysed type ranges from 0.03% of the area in the Masyw Mięguszowiecki microregion to 24.1% of the area in the Pogórze Gubałowskie, where numerous permanent steady streams occur.

The trough retention periodic type occurs in 15 microregions; mainly in the Tatry Zakopiańskie (25.1% of area), Masyw Waksmundzki (14.2% of area), and Wierchy Pięciostawiańsko-Białczańskie (14.1% of area) microregions. The smallest share of the analysed type was recorded in the Masyw Czerwonych Wierchów microregion (0.5% of the area). Periodic watercourses are abundant in these areas.

The infiltration-runoff type occurs in 19 microregions. The proportion of the analysed type ranges from 0.1% of the area (Grupa Osobitej-Bobrowca) to 26.5% of the area (Grań Orlej Perci). The presence in the Grań Orlej Perci microregion of Quaternary formations, mainly clays, clayey debris, rock rubble, and moraine covers, lithosols, regosols, screes, mounds, and rock debris influences the dominant share of the infiltration-runoff type.

The infiltration-runoff flood type was found to occur in five microregions, mainly in the Pogórze Przedtatrzańskie mesoregion – in Pogórze Gubałowskie (55.4% of area), Pogórze Brzegowskie (14.2% of area), and Pogórze Bukowińskie (10.3% of area). A significant share was also recorded in the Rów Zakopiański (19.8% of the area). The smallest share of this type was recorded in the Działy Poronińskie microregion (0.3% of area). This type includes very steep terrains, located in the flood zone, covered by forest vegetation and Quaternary materials including fluvial formations, fluvial-glacial formations, silt loam, loam, and sandy clay loam.

The complex infiltration-evapotranspiration hydrotope type occurs in 21 microregions. It is predominant in the microregion of the Działy Poronińskie (29.7% of the area), where a large share of Quaternary formations, mainly fluvial-glacial, loam, was recorded. A significant share is occupied by grassy vegetation and moderately and strongly sloping terrain. The lowest share of this type was recorded in the Masyw Waksmundzki and Masyw Kominiarski (0.1% of the area) microregions.

The infiltration-evapotranspiration flood type occurs in seven microregions, more than half of which is found in the Pogórze Przedtatrzańskie mesoregion, mainly in Pogórze Gubałowskie (33.6% of the area) and Pogórze Bukowińskie (31.8% of the area). A significant share was also recorded in the Rów Zakopiański (17.4% of the area). The smallest share of this type was recorded in the Pogórze Brzegowskie microregion (0.5% of the area). This type was found mainly in the Pogórze Przedtatrzańskie mesoregion due to its occurrence in river valleys with a high proportion of Quaternary formations, loam, and grassy vegetation. These areas are poor to moderately sloping.

The runoff-evapotranspiration type occurs in three microregions. This type is dominant in the Grań Orlej Perci microregion (56.0% of the area), in which, as previously mentioned, Quaternary formations, mainly loam, clayey debris, and stony weathering and moraine cover; lithosols, regosols, screes, mounds, and rock rubble occur.

The literature on hydrotope delimitation differs, among other things, in the detail of the methodology described and the results obtained. To delimit hydrotopes, many researchers use diverse, but usually similar, cartographic materials showing the diversity of lithology, soil cover, land use, relief, types of water circulation, and depth to groundwater. However, it is important to note that, depending on the level of detail of the units and the scale of the study, the environmental elements used vary. Generally, the higher the unit, the lower the number of environmental elements used to delineate it. For example, Ostaszewska (1984) used four elements of the environment to delineate hydrotopes and three elements to separate types of assemblages. In addition, the variability of each element was analysed with less detail than in the delimitation of hydrotopes. In so doing, the authors used various methods, such as overlaying the content of maps of environmental elements (e.g., Sołowiej 1977, Ostaszewska 1984, Jańczak 1985) and groupings based on similarity into higher-level units (e.g., Richling 1980, Ostaszewska 1984). Hydrological modelling has also been used, for example, Müller-Wohlfeil et al. 2000, Tilch et al. 2002.

Two research approaches can be distinguished in the works discussed, namely, the genetic approach, which relies on the delimitation of hydrotopes based on the genetic types of Quaternary sediments (e.g., Sołowiej 1976), and the functional approach, which assumes that water is the main criterion in the delimitation of hydrotopes (among others Sołowiej 1977, Richling 1980, Ostaszewska 1984, Pawłat-Zawrzykraj 2006a, b, Bartczak, Tyszkowski 2016).

As stated in Sołowiej (1977), water, lithology, and terrain morphometry are the most appropriate criteria for separating hydrotopes. It is correct to separate hydrotope complexes based on their water regime by lithology and land use, and separate hydrotopes by relief and land use. Jańczak (1985) states that lithology, relief, and land cover are the basic criteria for separating a hydrotope complex. Similarly, Richling (1980) and Richling and Ostaszewska (1983) argued that water circulation depends mainly on the relief and lithology of the area, while vegetation plays a lesser role.

In the present study, similar to many previous works (e.g., Sołowiej 1976, Richling 1980, Ostaszewska 1984, Jańczak 1985), four elements of the natural environment are observed. When comparing against works in the Lowlands, it is important to note that much greater variability was observed in the deep geological structure, which has a fundamental influence on water circulation in the mountains, and more varied slope gradients. In the present study, the map overlay method (individual hydrotopes were separated) was used to distinguish hydrotopes, similar to Sołowiej (1977), Richling (1980), Ostaszewska (1984), and Jańczak (1985). As in Richling (1980) and Ostaszewska (1984), the present study takes the names of the actual types to specify the proportion of the dominant water circulation type in the unit. Thus, a functional approach was used, and the main criterion for separating the units was water and its circulation.

It is also important to note the challenge of availability and the detail of cartographic data used in studies. The studies cited above were generally carried out over relatively small areas, in which it was possible to perform detailed field surveys to study individual elements of the natural environment. In the present study, covering a much larger area (the entire Polish Tatra Mountains and the southern part of Podhale), direct field mapping was not possible; the work is therefore based on available materials.

In some previous studies concerning hydrotopes subdivisions, the authors do not give the names of the subdivisions used, providing only descriptive characteristics of the units (e.g. Jańczak 1985, Sołowiej 1987) or an abbreviated code through which the element-criteria applied to the subdivisions can be read (e.g., Sołowiej 1977).

The authors used different names and characterised the separate units in different ways. It is important to note that the separated units have a mixed typological-regional character; their names refer not only to the features of the environment, but also to the location: some authors gave names specifying the type of water circulation present, others indicated its location, and some combined these two pieces of information. As further noted by Sołowiej (1976) and Bartkowski (1977), hydrotope complexes are based on relief forms, for example, the hydrotope complex of large river valleys, as well as separated hydrotope complexes with a dominant infiltration type. Moreover, Sołowiej (1977) studied the relationships between infiltration capacity and surface runoff and delineated four types of water regimes; these are also typological-regional units. In the present study, actual and potential hydrotopes were not assigned names; only after analysis was a name given to the hydrotope types, assuming that the name was derived from the dominant type of water circulation in the unit. As this study uses a functional criterion, in which water is assumed to be the main criterion in the delimitation of hydrotopes (Sołowiej 1976), and the study aimed to determine the nature of the water circulation of the area, hence, the names adopted indicate the dominant type of water circulation in the delimited unit. Similar names of hydrotopes were used by Sołowiej (1977), Richling (1980), Ostaszewska (1984), and Bartczak and Tyszkowski (2016).

Vertical differentiation of the hydrotope type system is visible mainly in the southern part of the Tatra Mountains, where on the highest ridges in the form of solid, impermeable rocks, the run-off type was recorded, and in the valleys covered by Quaternary formations, the infiltration type and the permanent and periodic trough retention type were determined. Thus, the results of the present study partly correlate with the hydrographic zones delineated by Wit-Jóźwik (1974). Considering the distribution of the separated hydrotope types, no clear belt-like arrangement was observed as seen in the geological structure and hydrographic regions and subregions delineated by Wit and Ziemońska (1960), Wit-Jóźwik (1974) and Żelazny et al. (2015). However, some convergence can be observed. According to the aforementioned authors, mainly infiltration and surface runoff are observed in the crystalline subregion. Similarly, in the present study, the southern part of the Tatra Mountains is characterised by clearly visible infiltration and runoff hydrotope types. In the region below the Tatra Mountains, according to Wit and Ziemońska (1960) and Wit-Jóźwik (1974), infiltration dominates; similarly, in the present study, infiltration and evapotranspiration hydrotope types were mostly found. There are also numerous patches of marsh retention in this area. The foothills region, according to the cited authors, is characterised by a predominance of surface runoff over infiltration. In the present study, mainly evapotranspirational and runoff types of hydrotopes are observed in the Podhale area. Infiltration flood types occur in the valley bottoms in this area.

The differentiation of hydrotope types does not directly relate to regional units, i.e., micro and mesoregions. It is possible to distinguish the hydrotope types that dominate in a given microregion; however, each microregion features a differentiation of hydrotope types.

In general, a latitudinal and meridional pattern of hydrotope types was identified in this work. In the southern part of the Tatra Mountains, the runoff type forms patches with an elongated course (latitudinal or meridional), referring to the course of the ridges. The areas of infiltration type refer to river valleys, depressions covered by Quaternary formations including debris, scree, rubble, rocks, sand, and gravel formations, fluvial, fluvial-glacial formations, and moraine covers. In most parts of the Podhale, patches of the runoff type have both a meridional and latitudinal pattern, denoting the course of the hills. The background to the infiltration and runoff type is the evapotranspiration type, which is dominant in the study area. The difference in the overall distribution on the map of hydrotope types, occurring between the results of the present study and those of the authors cited above, is due to the assumptions of the work. In the southern part of the Tatra Mountains, there is more surface runoff due to impermeable, solid rock and significant slopes. The further north one goes, the higher the proportion of evapotranspiration, related to the coverage of the area by forests and crops.