Wyniki wyszukiwania - BazTech

1

Dendroclimatological Analysis of Wild Pear Pyrus Pyraster (L.) Burgsd. From Biedrusko Military Area (West Poland) — Preliminary Study

Cedro A., Antkowiak W.

Geochronometria

|

2016

|

Vol. 43, no. 1

18--23

EN

European wild pear (Pyrus pyraster, syn. Pyrus communis subsp. pyraster L.) is widely distributed in Europe, but rarely studied by dendrochronologists. This preliminary study was aimed to assess the age and effect of climate on tree-ring width in the largest Polish population of P. pyraster, in Biedrusko military area (western Poland). On the basis of samples from 21 trees, a chronology (BIE) was constructed, covering 45 years (1963–2007). Mean tree-ring width in the studied trees is 1.92 mm. The performed analyses (pointer years, correlations, and response function) indicate that tree-ring width is strongly dependent on weather conditions in the year preceding formation of the tree-ring. Annual rings of pear trees were wide after cold and rainy previous summer and after rainy previous October, while in the current year, ring width was affected by insolation in February and temperature in August (positive correlations) and precipitation in May (negative correlation). The low similarity of the ring-width pattern and effect of climate on tree-ring width between this population and a wild pear population from the Bielinek Reserve, located 200 km away, indicate that tree-ring width in this species is strongly dependent on habitat and there is a need to continue dendrochronological analyses.

2

Success of wild pear Pyrus pyraster (L.) Burgsd. in colonization of steep sunny slopes : an interdisciplinary study in the Bielinek Reserve (NW Poland)

Antkowiak W., Cedro A., Prajs B., Wolko Ł., Michalak M.

Polish Journal of Ecology

|

2012

|

Vol. 60, nr 1

57-78

EN

A local population of Pyrus pyraster was studied in dry and warm habitats: xerothermic grasslands Potentillo-Stipetum capillatae and Adonido-Brachypodietum, as well as thermophilous oak forest Quercetum pubescentipetraeae in the forest-steppe Bielinek Reserve (NW Poland). Our aims were to assess: (1) the ability of this species to adapt to extremely dry sites, as a pioneer woody plant; (2) its phytosociological position; and (3) morphological variation and genetic diversity of the local population. The pear trees in Bielinek Reserve seem to reach an optimum in shrub communities of the class Rhamno-Prunetea, but tree age clearly indicates that the grasslands were colonized by wild pear trees already before the shrub communities developed. This indicates that P. pyraster can colonize very dry, eroded sites, such as steep sunny slopes covered by xerothermic grasslands. Wild pear trees form plant communities that are a seral stage followed by forest-shrub communities or thermophilous forests. The species in xerothermic shrub communities of the reserve shows a high constancy. It is also very resistant to extreme temperatures, insolation, drought, and erosion. Its tree-ring width (on average 1.1 mm per year) was strongly related to precipitation and temperature in spring and summer. High precipitation resulted in wider tree rings, while dry years (associated with high air temperature) caused a decrease in tree-ring width. Another significant factor is precipitation in winter, which had a positive influence on tree-ring width. Microsatellite markers revealed a high level of genetic diversity in this population. Our results suggest that wild pear can be recommended for afforestation of areas affected by droughts and disturbed sites in Central Europe. It can be used to increase the heterogeneity of the landscape, e.g. by creation of forest ecotones and for planting along roads and field margins, especially considering the predicted climate change.

3

Tree-ring chronologies of downy oak (quercus pubescens), pedunculate oak (q. Robur) and sessile oak (q. Petraea) in the Bielinek Nature Reserve : comparison of the climatic determinants of tree-ring width

Cedro A.

Geochronometria

|

2007

|

Vol. 26

39-45

EN

In 2004-2006, 50 trees of downy oak (Quercus pubescens), pedunculate oak (Q. robur) and sessile oak (Q. petraea) were sampled in the Bielinek Nature Reserve. The following chronologies were established from their tree-ring series: OMS of 212 years (1793-2004) for downy oaks well as D10 of 183 years (1817-1999) and D13 of 211 years (1789-1999) for the two indigenous oak species pedunculate and sessile oak, respectively. These chronologies were used for signature years and response function analyses. All three chronologies were highly similar, which points to identical responses to the ambient meteorological conditions. The radial increment of downy oak depends primarily on the amount of precipitation. A high annual sum of precipitation, copious rain in springsummer in particular, results in wide tree rings. Precipitation in form of rain and snow in winter, too, enhance tree growth by raising the groundwater level and improving the water supply in the habitat during the subsequent spring. Droughts in spring and summer, coupled with high air temperature, result in narrow rings. The tree-ring width/climate relationships at the two indigenous oak species are very similar to those of downy oak. Responses are, however, more distinct and with a higher statistical significance.

4

Dependence of radial growth of Pinus sylvestris L. from Western Pomerania on the rainfall and temperature conditions

Cedro A.

Geochronometria

|

2001

|

Vol. 20

69-74

EN

The paper deals with the influence of varying climatic conditions on radial growth of Scots Pine in the area of Western Pomerania. The research was aimed to evaluate the influence of air temperature and precipitation on dimensions of radial growth of the analysed tree species. The investigations demonstrated high dependence of the annual growth width upon temperature in winter and the beginning of spring. Precipitation influenced the annual growth in summer months, particularly in June and July. In the site with high level of ground water (very humid forest habitat) the rainfall had a negative effect on the annual growth width - contrary to the other analysed sites.