Search Results (5)

Catastrophic precipitation is an inherent feature of temperate climates. Its occurrence is a manifestation of climate change, but also of the variability of atmospheric circulation. Mountainous areas may be particularly vulnerable as they receive more precipitation and are also areas where relief plays an important role in modifying the distribution of precipitation. One such area is the Polish Western Carpathian Mountains, especially the area around the city of Bielsko-Biała, located at their foot and directly exposed to rain-bearing winds. In 2024, two episodes of unusually heavy precipitation in quick succession occurred in this area, resulting in severe damage to infrastructure. This painful experience inspired a study focusing on the frequency of such catastrophic precipitation events and their synoptic circumstances spanning the period from the mid-20th century to the present day. Daily precipitation totals covering the study period of 74 years were used to identify a category of catastrophic precipitation (here set at above 100 mm). The six events identified to match the criteria appeared from May to September, always accompanied by cyclonic circulation types with advection from the northern sector and with a cyclonic trough situation over southern Poland. The study showed that the leading role in their formation was played by deep convection, especially a Genoa low moving along the Vb Van Bebber track. The damage and destruction suffered as a result were a consequence of the cumulative impact of high-intensity rainfall, itself caused by a combination of specific synoptic thermodynamic and orographic conditions. Full article

The Golden Eagle Aquila chrysaetos (hereafter GE) is one of Europe’s largest avian top predators. The present study recognizes the habitat characteristics and food composition of the GE in Poland. The research was carried out in the Polish part of the Carpathian Mountains. The GEs built nests mainly on old coniferous trees and strongly preferred the Silver Fir Abies alba. On average, within a 5 km buffer around the nest, forests covered about 2/3 of the area, while open land with villages was at 31% and water was about 1%. Birds preferred areas with less forest cover than in the random points, but the nests were significantly further from the countryside than the distance measured for the drawn points distributed in the GEs’ range in Poland. Their diet during the breeding season was assessed by analyzing pellets and food remains. The proportion of birds was 55.7%, mammals was 43.4%, and reptiles was 0.9%. The ten most common prey species included the Domestic Pigeon Columba livia, the Ural Owl Strix uralensis, the Tawny Owl Strix aluco, the Buzzard Buteo buteo, the Roe Deer Capreolus capreolus, the Martens Martes sp., and the Red Fox Vulpes vulpes, which composed 70% of food items. Our results showed that the GE is a top predator, as evidenced by the high share of other predators—both mammal and bird species—in its diet, which constituted about 34% of identified preys. The diet of the studied GE population showed geographical variation, suggesting local adaptations to available prey species. The share of Roe Deer increased from west to east, indicating a higher availability in the less urbanized eastern part of the country. An analysis of general food categories showed that, as latitude increased, the share of captured birds among prey of the GEs declined, while the percentage of forest prey increased. Pigeons were prey of the GEs mainly in the western part of their range. The GEs often captured species with nocturnal activity—owls and martens, which were identified in most of the GEs’ territories. The proportion of mammals in the diet of the GE increased with an increase in the proportion of open areas, while the abundance of birds of prey and owls in the diet correlated with a higher proportion of forests. The greatest threat to Poland’s GE population is the reduction in semi-open areas with low human activity and low human population densities. Full article

Alnus viridis (Chaix) DC., green alder, is a fast-growing shrub that grows expansively in the European mountainside. In Poland, A. viridis naturally occurs only in the Bieszczady Mountains (south-eastern part of the country), above the upper forest border. In this study, we assessed the potential of green alder to expand in post-farming areas in the Bieszczady Mountains. We investigated the effects of topographical, climatic, and edaphic characteristics of four various study sites on the physiological and morphological properties of A. viridis leaves in order to answer the question whether the growth of plants in lower positions improves their physiological condition to such an extent that it increases the species invasiveness. This is the first comprehensive ecophysiological study of this species to be carried out in this part of Europe. The photochemical efficiency of PSII, the chlorophyll content, and leaf ¹³C and ¹⁵N discrimination were analyzed. On the basis of leaf radiation reflection, coefficients such as reflectance indices of anthocyanins, carotenoids, flavonoids (ARI2, CRI1, FRI), photochemical index of reflection (PRI), and the water band index (WBI) were calculated. We observed favorable physiological effects in A. viridis plants growing in locations below the upper forest border compared to plants growing in higher locations. As a result, A. viridis may become an invasive species and disturb the phytocoenotic balance of plant communities of the altitudinal zones in the Polish Western Carpathians. Full article

Prediction of spatial and temporal variability of air temperature in areas with complex topography is still a challenge for numerical weather prediction models. Simulation of atmosphere over complex terrain requires dense and accurate horizontal and vertical grids. In this study, verification results of three configurations of the Aire Limitée Adaptation Dynamique Développement International High-Resolution Limited Area Model (ALADIN-HIRLAM) numerical weather prediction (NWP) system, using two different horizontal and vertical resolutions and applied to the Polish Western Carpathian Mountains, are presented. One model of the ALADIN-HIRLAM NWP system is tested in two horizontal and vertical resolutions. Predicted air temperatures are compared with observations from stations located in different orographies. A comparison of model results with observations was conducted for three cold season intervals in 2017 and 2018. Statistical validation of model output demonstrates better model representativeness for stations located on hill and mountain tops compared to locations in valley bottoms. A comparison of results for two topography representations (2 × 2 km and 1 × 1 km) showed no statistically significant differences of root mean square error (RMSE) and bias between model results and observations. Full article

The Polish Carpathians, like many mountain areas in Europe, are currently facing dynamic land use changes that will shape their future landscapes. As there are many different possible scenarios of potential change, we compared three different land use scenarios up until the year 2060 and assessed their impact on the potential habitat connectivity of two large carnivores—wolf (Canis lupus) and lynx (Lynx lynx). We first analysed the main directions of change within and outside the pan-European wildlife corridor located in the western part of the Polish Carpathians. Then we calculated and compared least-cost paths among randomly selected points for each land use scenario separately. Our results showed that the main direction of change—forest cover increase—may positively influence habitat connectivity for both wolf and lynx. However, due to the future spread of settlements, this positive impact might be locally limited. Therefore, to realise the potential conservation opportunities resulting from on-going land use changes, adequate orientation of spatial planning towards habitat connectivity is crucial. Full article