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Liverworts of the 'Murowaniec' Nature Reserve in Central Poland

100%
Gorski P.
Roczniki Akademii Rolniczej w Poznaniu. Botanika-Steciana
|
2005
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tom 08
2
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The stand structure and natural regeneration of Abies alba Mill. in reserves on the northern margin of its distribution in SW Poland

80%
Szymura T. H.
Dendrobiology
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2007
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tom 57
55-62
The silver fir (Abies alba Mill.) in the area of Wał Trzebnicki is at the northern limit of its distribution in western Poland. This study was performed in three nature reserves with protected silver fir populations. The stands in these reserves were mixed, with complex spatial structure and abundant tree regeneration. The proportion of fir in stands was around 16% of DBHS, the age of trees reached around 130 years. The silver fir occurs mainly in the sapling stage, whereas the number of seedlings was very low. The results of this study show the influence of forest floor vegetation as well as litter type on the emergence of fir seedlings. The seedlings density was compared with the results of other studies from different geographical areas and stands type in Poland.
3

Long-term changes in stand composition of natural forest associations on the Roztocze Highlands (Eastern Poland)

70%
Maciejewski Z., Szwagrzyk J.
Polish Journal of Ecology
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2011
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tom 59
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nr 3
The purpose of this study was to determine the trends and rates of spontaneous changes in the structure and species composition of natural forests which are composed mostly of tree species growing at the limits of their natural range of distribution. We analyzed the demographic processes in populations of woody species in the years 1968‒2005. The investigations were conducted in strictly protected areas in the Roztoczański National Park (The Roztocze Highlands, Eastern Poland) on four 0.5-ha sample plots, established in the 1960s. These plots represented three forest communities: upland fir mixed forest Abietetum polonicum (Ap), Carpathian beech forest Dentario glandulosae–Fagetum (DgF), and pine-oaks mixed forest Querco roboris– Pinetum (QrP)). Measurements were conducted in 1968, 1978 (two sample plots only) and in two study periods (1993‒1995 and 2003‒2005). Measurements in the last two periods included canopy trees (DBH and height) forest regeneration (saplings, seedlings and germinants) as well as dead wood (snags and coarse woody debris). The results revealed significant and dynamic changes in the studied forests. The directions and rates of changes were different among forest communities. Silver fir (Abies alba Mill.) showed continuous decrease in all the forest associations. The highest rates of change were found in the DgF forest association. Data from the last measurement showed, that the rate of fir decline has slowed down, and in some cases even a slight increase of its share was recorded. However, the continuous decrease in abundance of the fir regeneration in all study plots suggests, that fir in the near future can be partly replaced by the broadleaved species. Among them, European beech (Fagus sylvatica L.) revealed the most dynamic species. It showed a systematic increase of it’s share in stand composition, according to the number of trees and basal area in all investigated plots. The largest increase of this species was recorded in the QrP forest association. Untill 1993 hornbeam (Carpinus betulus L.) developed well in the DgF association, and it also increased in abundance in the Ap association. The last measurements confirmed large increase the number of hornbeams in the DgF association, whereas it’s share in stand basal area revealed a weak downward tendency in both associations. After 1993 Norway spruce (Picea abies (L.) H. Karst.) grow only in the Ap forest communities, where its development is rather weak. The share of Norway spruce in forest composition has diminished systematically since 1968. The measurements from 2003 revealed a slight increase of the basal area of spruce and substantial decrease of its regeneration. Other tree species: Scots pine (Pinus sylvestris L.) and pedunculate oak (Quercus robur L.) in the successive measurements showed a systematic decrease of their number, basal area and share in the stand composition. There was also no natural regeneration of these species. Observed changes could be mainly attributed to natural rocesses of forests development (including natural disturbances) in general and to specific mechanisms of competition in forests composed of tree species growing close to the limits of their natural distribution ranges. In some cases the dynamics of researched species (hornbeam, pine and oak) can be explained as the regeneration processes of ecosystems affected previously by human activities.
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