Piotr Owczarek

DENDROCHRONOLOGICAL RECORDS OF DEBRIS FLOW AND AVALANCHE ACTIVITY IN A MID-MOUNTAIN FOREST ZONE (EASTERN SUDETES - CENTRAL EUROPE)

Dendrochronological Records of Debris Flow and Avalanche Activity in a Mid-Mountain Forest Zone (Eastern Sudetes — Central Europe) Dendrochronological methods were used to determine the frequency of debris flow/avalanche events in a forest zone. A debris flow and avalanche track located in the Eastern Sudetes Mountains (Central Europe) was analysed. The length of the youngest debris flow/avalanche track is about 750 m. Three distinct sections of the debris flow can be identified along the longitudinal section: niche, gully and tongue. The dendrochronological study shows that trees started growing on the margins of the debris flow between 1908 and 1963. Hence, debris flow and/or avalanche events occurred on this slope at the turn of the 19th and 20th centuries. All trees collected from the tongue started growing between 1935 and 1964. However, a large debris flow event took place several years before, most probably during an extraordinary rainfall in June 1921. Following this event, several relatively large debris flows have occurred during the growing season, the strongest dendrochronologically confirmed events occurring in 1968, 1971-1972, 1991, 1997 and probably in 1977. Spring debris flow events induced by snow melt and/or avalanches have occurred in 1994 and 2004. The results suggest that with favourable geological conditions, debris flows can occur very frequently within entirely forested slopes.

Dendrochronology and extreme pointer years in the tree-ring record (AD 1951–2011) of polar willow from southwestern Spitsbergen (Svalbard, Norway)

Abstract Greater warmth and precipitation over the past several decades in the High Arctic, as recorded in meteorological data, have caused shrub expansion and affected growth ring widths. The main aim of the study was to develop a tree-ring chronology of polar willow (Salix polaris Wahlenb.) from southwest Spitsbergen, attempt to explain its extreme pointer years (extremely low value of growth-ring widths) and to demonstrate the dendrochronological potential of this species. This plant is a deciduous, prostrate, creeping dwarf shrub that produces anatomically distinct annual growth rings with the consistent ring width variation. After using serial sectioning we developed rigorously cross-dated ring width chronology covering the period 1951–2011. Since the beginning of the 1980s an increase of the mean and maximum growth ring width has been observed which is consistent with the increase of both temperature and precipitation in the Arctic reported from meteorological sources. Nine negative extreme years were distinguished and explained by complex hydroclimatic drivers, which highlight the importance of availability of moisture from snowpack and spring precipitation. An additional negative factor present in the years with very low dwarf shrubs growth is rapid thawing and fast freezing during winter as well as low sunshine duration. Our results contradict the prior assumption that inter-annual tree growth variability of dwarf shrubs from polar regions is controlled simply by temperature.

The First Dendrochronological Dating of Timber from Tajikistan – Potential for Developing a Millennial Tree-Ring Record

Abstract We are reporting the first dendrochronological dating of timber from Tajikistan. Thirty samples were collected from two old buildings from a village located in the western Pamir-Alay; eight cores were taken from temple. Most of the construction wood was juniper species. The object chronologies crossdated well with the previously published chronology based on living juniper trees from western Pamir-Alay. The results of dating revealed that investigated structures are composed of wood coming from several periods. The oldest pieces of wood dated back to the 11th and 12th Centuries. Most timber samples come from the turn of the 17th and 18th Centuries, which were probably the period of intense development of the Artuch village. Besides dating of the wood samples from these historic structures, our investigation provides the opportunity to extend the currently existing regional tree-ring chronology for future climate reconstruction of the Pamir-Alay and High Asia. Dated sequences were assembled into a 1012-year chronology spanning the period 945–2014 C.E. and strengthened the replication of its earliest part (with critical 0.85 EPS value since the beginning of the 13th Century).

Attractiveness of protected areas for geotourism purposes from the perspective of visitors: the example of Babiogórski National Park (Poland)

Abstract This article examines the tourist role of protected areas important for their unanimated nature potential. In Poland the highest form of legal protection is a national park. Babiogórski National Parks is one of 23 national parks in Poland. The aim of this article is to present its tourist attraction based on its geotourist potential considered by tourists who visit this park. At the beginning a brief history of protection of Babia Góra is presented. Based on stock-taking sightseeing method an analysis of the most important tourist attractiveness elements (like infrastructure or tourist values) is done. The focus on the values of unanimated nature is made grouping them into four main categories. As the result of research on infrastructure the most important accommodation units were indicated present at the surroundings of this National Park which is vital for its tourist capacity. For the correct functioning of tourist movement at the protected area the supporting infrastructure is important bearing a lot of functions. The function of channeling of the tourist movement as well as the didactic function are the most important for protection and correct use of geotourist values. Among the many elements of the supporting infrastructure the most important ones are tourist and didactic routes (their course and themes are presented). The most important part of the article is the presentation of the participants of the tourist movement opinions on the Babiogórski National Park tourist attractiveness. A survey was conducted and then analysed on 308 respondents in 2011. They were asked to judge both the quality of infrastructure as well as attraction of geotourist values together with their adaptation to reception by the tourist movement. The results analysis served as a base to appraise the state and perspectives for the geotourism development in Babiogórski National Park from the point of view of the receivers of tourist product i.e. the protected area.

A tree-ring and GIS assessment of mass-movement hazard in the Moxi basin (Sichuan, China)

The goal of our study is to estimate the frequencies and magnitudes of mass movements of differing origin and scale endangering the population of the Moxi basin. The ages of 30 trees were determined indicating the date of the last large debris flow. In addition we determined the dates of smaller debris flows wounding the stems of 43 trees and the dates of rockfalls injuring the stems of 15 trees. The results allowed the recurrence intervals of the mass movements observed in each study site to be calculated. Based on the results from three study sites representing typical mass-movement hazards, the densely inhabited main valley of the Moxi basin is affected by 40 large debris flows, hundreds of smaller debris flows and thousands of single rockfalls per century. The GIS-based survey indicates that the hazard affects as much as 27.07% of developed area of the Moxi basin. However, thanks to sustainable land use, the majority is affected by manageable, high frequency, but middle- to low-magnitude phenomena.