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Dendrochronological dating as the basis for developing a landslide hazard map – An example from the Western Carpathians, Poland

Łuszczyńska K., Wistuba M., Malik I., Krąpiec M., Szypuła B.

Geochronometria

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2018

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Vol. 45, no. 1

173--184

EN

Most landslide hazard maps are developed on the basis of an area’s susceptibility to a landslide occurrence, but dendrochronological techniques allows one to develop maps based on past landslide activity. The aim of the study was to use dendrochronological techniques to develop a landslide hazard map for a large area, covering 3.75 km2. We collected cores from 131 trees growing on 46 sampling sites, measured tree-ring width, and dated growth eccentricity events (which occur when tree rings of different widths are formed on opposite sides of a trunk), recording the landslide events which had occurred over the previous several dozen years. Then, the number of landslide events per decade was calculated at every sampling site. We interpolated the values obtained, added layers with houses and roads, and developed a landslide hazard map. The map highlights areas which are potentially safe for existing buildings, roads and future development. The main advantage of a landslide hazard map developed on the basis of dendrochronological data is the possibility of acquiring long series of data on landslide activity over large areas at a relatively low cost. The main disadvantage is that the results obtained relate to the measurement of anatomical changes and the macroscopic characteristics of the ring structure occurring in the wood of tilted trees, and these factors merely provide indirect information about the time of the landslide event occurrence.

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Can we distinguish between tree-ring eccentricity developed as a result of landsliding and prevailing winds? consequences for dendrochronological dating

Wistuba M., Malik I., Krąpiec M.

Geochronometria

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2018

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Vol. 45, no. 1

223--234

EN

The aim of our study was to compare patterns of tree-ring eccentricity developed in Norway spruce trees as a result of landsliding with the one caused by the prevailing wind (in 2 study sites), and with the normal growth of trees (in 2 reference sites). We sampled 20 trees per study site and 10 per reference site. Two cores were taken from each tree (120 cores in total) from the upslope and downslope, windward and leeward sides of stems. Ring widths measured on opposite sides of stems were compared using the method of percent eccentricity index. Graphs of the index obtained for individual trees were analysed. Statistical indicators were calculated for a percent eccentricity index. Disturbance events were dated and the response index was calculated. The results show that the patterns of eccentricity developed as a result of the prevailing winds and due to landsliding differ from one another and from the reference sites. The results suggest that the impact of the prevailing wind on tree growth is more severe than the impact of landsliding. The difference may result from the slow-moving character of the landslide under study. The results, however, indicate that wind impact should be taken into account in dendrogeomorphic research and that the impact of mass movements should be considered in dendroecological studies on wind.

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Relief evolution of landslide slopes in the Kamienne Mts (Central Sudetes, Poland) - analysis of a high-resolution DEM from airborne LiDAR

Osika A., Wistuba M., Malik I.

Contemporary Trends in Geoscience

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2018

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Vol. 7, iss. 1

1--20

EN

The aim of the study is to reconstruct the development of landslide relief in the Kamienne Mountains (Central Sudetes, SW Poland) based on a DEM from LiDAR data. Analyses of relief and geological maps in ArcGIS 10.5 and of slope cross-sections in Surfer 14 allowed to distinguish different types of landslide relief, developed in latites and trachybasalts lying above claystones and mudstones. The types vary from small, poorly visible landslides to vast landslides with complex relief. They were interpreted as consecutive stages of geomorphic evolution of hillslope-valley topography of the study area. Two main schemes have been established which explain the development of landslide slopes in the Kamienne Mts: (1) upslope, from the base of the slope towards the mountain ridge and (2) downslope, beginning on the top of the mountain ridge. The direction of landslide development depends on the thickness of volcanic rocks in relation to underlying sedimentary rocks. When the latter appear only in the lowest part of the slope, landslides develop upslope. If sedimentary rocks dominate on the slope and volcanic rocks form only its uppermost part, landslides develop downslope. The results show that landsliding leads to significant modifications of relief of the study area, including complete degradation of mountain ridges.

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Activity of Slow-Moving Landslides Recorded in Eccentric Tree Rings of Norway Spruce Trees (Picea Abies Karst.) — An Example from the Kamienne MTS. (Sudetes MTS., Central Europe)

Malik I., Wistuba M., Migoń P., Fajer M.

Geochronometria

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2016

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Vol. 43, no. 1

24--37

EN

We found ubiquitous evidence of ongoing slope instability by analysing the variability of tree-ring eccentricity index in trees growing on three apparently relict landslide slopes in the Sudetes (Poland, Central Europe). Slow movement of these landslide bodies occurs in the present-day conditions and is recorded almost every year, although with variable intensity. Correlation of dendrochronological record with the rainfall record from a nearby station in Mieroszów for the 1977–2007 period is very poor for two deep-seated rotational slides at Mt Suchawa and Mt Turzyna but considerably better for a shallow flowslide at Mt Garbatka. While this may reflect higher permeability of heavily jointed rocks involved in deep-seated sliding this could be linked with imperfections in the rainfall record. Dendrochronology proved capable of detecting minor displacements within landslides which otherwise show no geomorphic evidence of recent activity. Therefore, claims for the entirely relict nature of the landslides are not substantiated.

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Wahania właściwości mieszanek mineralno-asfaltowych i ich wpływ na prognozowaną żywotność dróg

Wistuba M., Mollenhauer K., Walther A., Murawski W., Murawski W.

Nawierzchnie Asfaltowe

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2015

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Nr 3

4--9

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Czynniki uaktywniające i zróżnicowanie czasowe przemieszczeń koluwiów w różnych częściach stoku osuwiskowego : analiza dendrochronologiczna na przykładzie osuwiska Skalka (Moravskoslezské Beskydy)

Łuszczyńska K., Wistuba M.

Landform Analysis

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2015

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Vol. 28

103--113

PL

Celem badań było określenie zmienności czasowej osuwania i stwierdzenie różnic w aktywności poszczególnych części stoku osuwiskowego. Zastosowano metody dendrochronologiczne: dla 60 świerków pospolitych analizowano dekoncentryczność przyrostów rocznych. Największą dynamikę osuwania stwierdzono w latach: 1975, 1993, 1985, 1968–1969, 1995. Liczba zaburzeń wzrostu radialnego drewna świadczących o osuwaniu w poszczególnych latach dobrze odpowiada przebiegowi sum opadów półrocza letniego (np. osuwanie i opady w latach: 1968, 1972, 1975, 1977, 1985, 2010) oraz w mniejszym stopniu zimowego. Wyniki wskazują na nierównoczesną aktywność poszczególnych części osuwiska i uruchamianie różnych jego partii podczas różnych epizodów opadowych oraz prawdopodobnie w efekcie innych czynników uaktywniających (np. trzęsień ziemi z lat 1992–1993 o epicentrach w Beskidzie Sądeckim).

EN

The aim of the study was to determine the temporal variability o landsliding and differences in the activity of individual part of a small landslide. Dendrochronological methods have been applied: tree-ring eccentricity was analysed for 60 Norway spruce trees. The most dynamic landsliding occurred in: 1975, 1993, 1985, 1968–1969 and 1995. The number of wood-growth disturbances recording landsliding in particular years matches well with precipitation totals for summer half-years (e.g. landsliding and precipitation in: 1968, 1972, 1975, 1977, 1985, 2010) and to the smaller degree with totals for winter half-years (e.g. 1961). Results indicate uneven activity of particular landslide sections. The movement in particular parts of the landslide is triggered during various precipitation events or due to other factors (e.g. 1992–1993 earthquakes with epicentres in Beskid Sądecki Mts).

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Historical water-powered ferrous metallurgy reconstructed from tree-rings and lacustrine deposits (Mała Panew Basin, southern Poland)

Malik I., Wistuba M., Opała M., Franek M., Woskowicz-Ślęzak B., Mańczyk G., Tyrol Cz.

Geochronometria

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2015

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Vol. 42, no.1

79--90

EN

According to historical sources in the basin of Mała Panew River there were at least 56 water- powered iron smelters from 14th–19th century. Now only two metallurgy plants work in the area. Many of the former smelting settlements ceased to exist. Historical data on the smelting industry in the area are often scarce. The aim of the study was to reconstruct the history of ferrous metallurgy from (1) the remains of wooden historical buildings, (2) remains of charcoal kilns and (3) deposits from former smelter pond. Results show that Regolowiec smelting settlement existed already in the 17th century (at least several decades earlier than historical written sources suggest) and was later repaired after destruction caused probably by floods. Charcoal used for iron smelting in the ironworks in Brusiek on the Mała Panew River was burnt at the turn of the 18th century. This is in accordance with historical sources indicating particular prosperity of the metallurgy in that period. Upstream of the ironworks in Brusiek in the first half of the 17th century a large pond existed flooding the floor of the Mała Panew valley. Study has shown that the pond was at least 100 years older than historical sources have indicated.

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Human-planted alder trees as a protection against debris flows (a dendrochronological study from the Moxi Basin, Southwestern China)

Malik I., Tie Y., Owczarek P., Wistuba M., Pilorz W., Woskowicz-Ślęzak B.

Geochronometria

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2013

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Vol. 40, no. 3

208--216

EN

Large debris flows have destroyed the infrastructure and caused the death of people living in the Moxi Basin (Sichuan Province, Southwestern China). Inhabitants of the Moxi Basin live on the flat surfaces of debris-flow fans, which are also attractive for farming. During the monsoon season debris flows are being formed above the fans. Debris flows can destroy the houses of any people liv-ing within the fan surfaces. In order to prevent the adverse effects of flows, people plant alder trees (Alnus nepalensis) at the mouths of debris flow gullies running above debris flow fans. Alders are able to capture the debris transported during flow events. Trees are well adapted to surviving in con-ditions of environmental stress connected with abrupt transport and deposition of sediment from de-bris flows. Numerous wounds, tilting and bending of alder trees caused by debris flows only very rarely cause the death of trees. By dating scars and dating the time of alder tilting (through the analy-sis of annual rings), we have determined the frequency of debris flows occurring at the mouth of the Daozhao valley. In 1980-2012 within the studied debris-flow fan and the Daozhao gully, 2 large de-bris flow events occurred (1996, 2005) and some smaller events were probably recorded every 2-3 years.

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Dendrochronological methods for reconstructing mass movements - an example of landslide activity analysis using tree-ring eccentricity

Malik I., Wistuba M.

Geochronometria

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2012

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Vol. 39, no. 3

180-196

EN

Dendrochronological methods can be applied to the reconstruction of different types of en-vironmental events such as climate changes, fires, glacier movements, floods, earthquakes, volcano activity. In the field of geomorphology dendrochronology is increasingly frequently used for the abso-lute dating of different types of mass-movements (rock falls, landslides and debris flows, etc.). Trees growing on slopes transformed by mass-movements are tilted and wounded while their stems and root systems are exposed or buried under sediment. These events are recorded in wood anatomy as eccen-tric growth, reaction wood, scar overgrowth by callous tissue, changes in cell size or adventitious root production. Dating changes in wood anatomy allows to date and precisely reconstruct the spatial and temporal occurrence of mass-movements with at least one year resolution. The paper provides a re-view of existing dendrochronological tools used in geomorphology and also an example of the appli-cation of eccentric tree-growth to reconstruct landsliding. Using tree-ring eccentricity allows to (1) obtain a dynamic depiction of slopes, (2) study landslide activity, not only contemporary, but also in the last tens of hundreds of years (depending on the stand age).

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Dendrochronologiczne wskaźniki fluwialnej erozji i depozycji w ujściowych odcinkach dopływów Černej Opavy (Hrubý Jeseník, Sudety Wschodnie)

Wistuba M.

Landform Analysis

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2008

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Vol. 9

394--397