ABSTRACT
The development of ski infrastructure in mountainous areas has a significant impact on the development of erosion landforms and modification of existing landforms on slopes. The main purpose of our study was to determine the effects of ski run construction and artificial snowmaking on the development of channel heads and drainage lines as well as pattern of processes occurring along longitudinal profile of stream channel. The research was performed in the Remiaszów catchment on two ski runs in the Bialczanska Kotelnica ski area (the Polish Inner Carpathians). Analysis of the location of the channel head of the Remiaszów Stream catchment over time was performed on the basis of multi-temporal DEMs generated using high resolution LiDAR data. The data were obtained via two ALS scans (Airborne Laser Scanning): before the 2013 and after 2016 ski run construction, as well as TLS (Terrestrial Laser Scanning) conducted in 2017 and in the course of fieldwork in 2018 using GPS RTK. The construction of ski runs leads to the formation of new channel heads, all of which develop in drainage ditches. Three distinct zones emerge in the longitudinal profile: 1) artificially concentrated flow zone, 2) forced, dispersed flow zone, 3) rejuvenated, concentrated flow zone. This means that two channel head formation zones become available in the longitudinal profile. Large inflows of water (200% or more) due to artificial snowmaking lead to bidirectional development of the valley network. In general, identification of the channel head pattern in area of ski run construction play important role in understanding of the sustainable development of mountain ecosystem.
ABSTRACT
Rockfall leads to visible changes in mountain areas and as high-magnitude event has geohazard potential and should be monitored. On forested slopes, active rockfall could be identified with high precision from visible anatomical changes in tree-rings. To discern possible rockfall events in the Tatra Mountains, dendrogeomorphologic methods were applied and correlated with meteorological conditions. Field research was carried out on Norway Spruce (Picea abies L. Karst) in the Koscieliska Valley. Rockfall signals (RSs) were obtained from both qualitative (scars and traumatic resin ducts) data and quantitative (growth release and suppression) data. Multiple regression and ANOVA analysis were employed to recognize the meteorological conditions, which cause rockfall activity. Different periods of rockfall activity were observed during the years 1950-2014. The weakest activity was observed during 1950-1970 while after 1970 a continuous increase in rockfall activity was observed in our study. There was a clear peak in the number of RSs recorded per year in 1985. Cumulative precipitation and temperatures for January, March, May, June, July, August, September and October are statistically significant as the periods of the year in which rockfall is activated in the Tatra Mountains. In terms of activity, three different Levels of Rockfall Activity (LoRAs) were recognized and show significant correlation with the meteorological data. Distinguished meteorological control factors determining rockfall explains 53% of the total parameters determining rockfall activity. The complexity of the rockfall process means that a better understanding of local conditions and the possible uncertainties associated with the dendrogeomorphologic method and the quality of the meteorological data is needed.
ABSTRACT
In the last decade increasing popularity of winter tourism in mountain areas in Poland influenced development of ski infrastructure. This type of human activity may induce changes in mountain relief. The purpose of the study was to quantify ongoing change patterns via: (i) a determination of spatial and quantitative changes in catchment covered by new ski runs, (ii) a determination of the effect of new ski runs on the rejuvenation of relief in valleys adjacent to ski runs, (iii) an identification of changes in the surface runoff pattern before and after the construction of ski runs. The research was carried out in the Remiaszów catchment on two ski runs (southern Poland). Airborne Laser Scanning (ALS) data from 2013 and 2016 were also used in the study along with Terrestrial Laser Scanning (TLS) data from 2015. LiDAR (Light Detection and Ranging) point clouds were interpolated to create multi-temporal DEMs and then these DEMs were used to derive DoDs. These were used to identify erosion and accumulation zones. The Convergence Index (CI) was used to determine the direction of surface runoff. The largest changes in relief were observed in areas with ski runs, with ski run E lowering an average of 0.07m (±0.03m), and ski run N an average of 0.12m (±0.03m). The entire area lowered about 0.02m. The construction of new ski runs resulted in a rejuvenation of denudation valleys located in the vicinity of existing ski runs. Valley incisions reaching 1.5m (±0.15m) were observed. Both the convergence and divergence zones for surface runoff were identified, which made it possible to show changes in the geometry of flow direction. The identification of these sites may help forecast erosion and deposition zones. In general, this may make it easier to identify areas substantially susceptible to relief change.
