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EN
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.
EN
An annually resolved and absolutely dated ring-width chronology spanning 443 years has been constructed using the historical and living-tree Scots pine samples from the Upper Silesia, south of Poland. The constructed regional chronology, based on six object chronologies, covers the period of 1568–2010. It is composed of 178 wood samples with the mean correlation of 0.51, mean series length of 104 years and mean EPS of 0.85. In total, 65 extreme years were distinguished. Their independent verification, based on the historical and meteorological data, showed significant correlation with the exceptionally cold/mild winters as well as severe droughts. The comparison of the extreme years with the other Polish pine chronologies showed similarities in the years with the anomalous winter conditions. Some extreme years can be associated with the exceptional pluvial conditions; these years are common in the Central European hydroclimatic tree-ring records. The construction of this regional pine chronology enables for the absolute dating of many architectural monuments from investigated region. The application of the new chronology for the dating of local wood can support interpretations of changes in the environment of the Upper Silesian region. In the future it can also be used as the basis for climate reconstruction.
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.
EN
Samples from Mongolian Ephedra (Ephedra equisetina Bunge) was collected in the Zaravshan Mountains (the Fann Mountains), Tajikistan. The wood of Ephedra is ring-porous with well-defined growth rings. Annual ring widths were measured, individual series were first cross-dated and then averaged as a standard chronology. Correlations were calculated between the standard ring-width chronology and monthly climate data recorded in the weather station Iskanderkul. Dendroclimatological analysis showed that July temperature is the growth limiting factor of this species. Our study has shown high dendrochronological potential of Ephedra.
EN
Due to the lack of maintenance, abandoned cemeteries are often incorporated into the landscape. In many cases the information about the age of the cemetery is unavailable. To find out the approximate time of the formation of the cemetery the information recorded in the annual tree and shrub rings can be used. One of the most common tree species, planted for ornamental and symbolic purposes on the cemeteries, are Thuja orientalis and Thuja occidentalis. Alien to the Polish flora, these species adapted well to the local habitat and climatic conditions. The paper presents an attempt to apply dendrochronological dating to determine the age of the abandoned cemeteries in the region of the Great Masurian Lakes, part of the Masurian Lake District (north-eastern Poland). The study included five abandoned cemeteries. In total, 15 cores were taken from the trees. After applying the standard dendrochronological method, local chronologies for the studied species were established. The research indicated that the oldest found specimens - over 70 yrs old - are Thuja occidentalis individuals growing at the Słabowo cemetery. At the other sites the specimens of both Thuja species date back to the 1960s and early 1970s. Compared to the historical information regarding the age and origin of the studied objects, thujas growing there are much younger than the age of the cemeteries foundation. The presented method proved to be very helpful in understanding the time of Thuja occidentalis and Thuja orientalis introduction at the investigated cemeteries.
PL
Porzucone cmentarze w związku z brakiem pielęgnacji często wkomponowują się w krajobraz. Niejednokrotnie brak jest zachowanych informacji o wieku cmentarza. Aby poznać przybliżony wiek powstania cmentarza można posłużyć się informacji zapisanymi w przyrostach rocznych drzew i krzewów. Jednymi z najczęściej występujących drzewiastych gatunków sadzonych w celach ozdobnych i symbolicznych na cmentarzach są Thuja orientalis i Thuja occidentalis. Te obce dla flory polskiej gatunki, doskonale zaadaptowały się do zastanych warunków siedliskowych i klimatycznych. W pracy przedstawiono próbę zastosowania metody datowania dendrochronologicznego do określenia wieku porzuconych cmentarzy z Krainy Wielkich Jezior Mazurskich. Badaniem objęto 5 porzuconych cmentarzy. Ogółem pobrano 15 wywiertów z drzew. Po zastosowaniu standardowej metody dendrochronologicznej, utworzono lokalne chronologie przyrostowe dla badanych gatunków. Badania wykazały, iż najstarsze okazały się być okazy Thuja occidentalis występujące na cmentarzu Słabowo, których wiek wynosi ponad 70 lat. Na pozostałych obiektach rosnące okazy obydwu gatunków żywotników datowane są na lata 60. i początek lat 70.XX wiek. W porównaniu z informacjami historycznymi o wieku i pochodzeniu badanych obiektów rosnące na nich okazy żywotników są znacznie młodsze niż wiek założenia cmentarzy. Przedstawiona metoda okazała się być niezwykle pomocna w poznaniu czasu wprowadzenia żywotników Thuja occidentalis i Thuja orientalis na badanych cmentarzach.
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