Wyniki wyszukiwania - BazTech

1

Past and contemporary changes in forest cover and forest continuity in relation to soils (Southern Latvia)

Fescenko A., Nikodemus O., Brūmelis G.

Polish Journal of Ecology

|

2014

|

Vol. 62, nr 4

625--638

EN

A set of medium-scale historical maps was used to reconstruct changes in spatial patterns of forest area during the last 220 years in an agricultural matrix of north-eastern Europe (Zemgale region, Latvia). Changes in total forest area by soils were determined, as well as the time period of continuous forest cover. Proportion of protected area for each soil trophic group was also calculated. Patterns of recent forest development differed between soil trophic groups. Afforestation occurred mainly on wet and poor soils in the 19th and 20th centuries, while the proportion of woodland area on fertile soils typical for nemoral forests was fairly stable. Only 1% of the fertile soil area has been covered by continuous forest for more than 220 years, and only 11% of them are protected. Nemoral deciduous forests cover only 15% of their potential natural vegetation area of forested eutrophic soils. Therefore, in regard to habitat protection that is representative of natural distribution of ecosystems, priority in conservation should be given to forests on fertile soils.

2

Zmiany powierzchni leśnej wybranych terenów osadniczych Ziemi Lubuskiej w latach 1822 -2003

Wojterska M., Szrama K.

Prace Komisji Krajobrazu Kulturowego

|

2012

|

nr 16

181--190

PL

Badania nad szatą roślinną różnych typów osadniczych prowadzone są na terenie zachodniej Polski od 2007 r. Wśród 140 analizowanych osad na terenie Ziemi Lubuskiej dominują owalnice (65) oraz ulicówki (25). Szczegółowe studia roślinności na poziomie kompleksów zbiorowisk przeprowadzono w 33 obiektach o najlepiej zachowanej strukturze, z których większość powstała w XIII i XIV wieku. W niniejszym opracowaniu dane te zostały uzupełnione o charakterystykę przemian krajobrazu w otoczeniu 15 z tych wsi, dla których dostępne były historyczne materiały kartograficzne. Szczególną uwagę zwrócono na zmiany powierzchni leśnej, jako wskaźnika natężenia antropopresji. Wykorzystano w tym celu mapy z lat 1822-1828, 1933-1938 oraz 2003. Dla każdego przedziału czasowego obliczony został udział powierzchniowy lasów. Uzyskane wyniki potwierdzają tendencję wzrostu powierzchni leśnej w ostatnich dziesięcioleciach, przy jednoczesnej wyraźnej dynamice przemian krajobrazu w całym analizowanym okresie. Podobny udział powierzchniowy lasów na mapach z lat 1822-28 i współczesnych nie oznacza trwałości kompleksów leśnych. W całym okresie objętym badaniami obserwowane jest powstawanie i zanikanie powierzchni leśnych.

EN

Vegetation studies in different types of settlements are conducted in western Poland since 2007. Out of 140 analysed settlements in the Ziemia Lubuska region, the most common were villages of oval (65) and linear (25) shape. For detailed vegetation studies conducted within spatial complexes, 33 settlements with best preserved structure have been chosen. Their origin has been traced back to the XIII or XIV century. In this study those data have been completed with the description of landscape transformation around 15 villages, for which the historical cartographic sources were available. The share of forests, as indicator of intensity of human impact has been estimated on the maps from the years 1822-1828, 1933-1938 and 2003. The obtained results confirm the tendency of the increment of forest area in last decades. There is however distinct dynamics in the landscape transformation. Similar share of forests on maps from 1822-28 and on contemporary ones does not indicate their persistence, there are observed both decline and emerging of new forest areas.

3

Small scale spatial pattern of a soil seed bank in an old-growth deciduous forest

Wódkiewicz K., Kwiatkowska-Falińska A.

Polish Journal of Ecology

|

2010

|

Vol. 58, nr 3

487-500

EN

We studied an old growth deciduous forest seed bank to examine how its potential role in regeneration is shaped by natural forest environment. Our research questions were: is the spatial pattern of seed bank influenced by local variation in elevation, soil moisture and light intensity, and what is the impact of herb layer characteristics on seed bank pattern. We recorded species composition of the herb layer and seed bank on a 2 x 40 m study plot divided into 20 quadrates, situated in a natural oak-hornbeam forest, in the Białowieża Primeval Forest, (NE Poland). Soil cores were sampled from two soil layers (0-5 cm and 5-10 cm) yielding altogether 40 samples of a total 15.9 dm[^3] and 0.159 m[^2]. Seeds were extracted from soil samples under a microscope. Ellenberg indicator values were used to characterize light (L) and moisture (F) conditions. Relative quadrate elevation was averaged for nine points. There were 6.65 x 10[^3] seeds m[^-2] in upper soil layer and 3.00 x 10[^3] seeds m[^-2] in lower soil layer. Seed bank structure constituted of patches 6 m diameter in the upper soil layer and 4 m in the lower soil layer. Aggregated pattern of the seed bank was influenced by clumped distribution of plants in the herb layer. Seed bank species richness in the upper soil layer was correlated with moisture (r = 0.485, P =0.03) and light (r = 0.526, P = 0.0172) values. Seed densities were correlated with moisture (r = 0.848 P <0.0001 upper and r = 0.491 P = 0.0278 lower soil layer) and light (r = 0.803 P <0.0001 upper and r = 0.751 P = 0.0001 lower soil layer). Seed density in upper soil layer was negatively correlated with elevation (r =.0.485 P = 0.0422). Higher seed density and species richness of the seed bank associated with better light conditions and higher moisture is probably caused by higher seed production in favourable conditions, and factors promoting seed persistence in soil. Our results indicate, that even subtle changes in light, moisture and mean relative elevation can shape seed bank spatial pattern on a fine local scale, differentiating the response of this community to small scale disturbances present in natural forests.