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EN
The human induced changes affect the transformation of different plant communities. In some cases this process can contribute to increase in local biodiversity, but it depends on type and manner of human activity involved. The main aim of this study is to answer the question how two anthropogenic factors (former and current) can modify the species composition in forest phytocoenoses. The study area is situated in the southern Poland (Małopolska Upland). The studies were carried out on two former (19th century) mining fields where planting Common Beech Fagus sylvatica (field A) and Scots Pine Pinus sylvestris (field B) have been done since the first half of the 20th century. On gob piles (sites transformed by former iron-ore mining), single-species beech (field A) or pine (field B) tree stands are undergoing secondary succession, and transform into multi-species, fertile deciduous forests. This secondary communities corresponding to the types of new, fertile soils (formed by clayey-loamy material of gob piles), generated as a result of mining activities. Whereas, on non-transformed areas forest communities with floristic structures and composition linked to poor and acidophilous phytocoenoses developed. These communities are also compatible with their respective, primary habitats (acid, poor, and sandy soils). Nonetheless, the secondary succession of forest communities on gob piles can be disturbed. In the herb layer of fertile habitats of post-mining sites where Pinus sylverstis was planted (field B) acidophilous species among mesophilous forest species were noted. This process of acidification of humus layer is induced by the fall of needles of pines and it has not been observed in communities with planted Fagus sylvatica (field A). It was found that previous mining activities now affect the secondary succession in the forest communities of northern part of the Małopolska Upland because they have created new habitats where process of forming mesophilous phytocoenoses was observed. Accordingly, former human activity leads to the increase in local biodiversity. On the other side current forest management can reduce this effect as a result of planting tree species which acidify these fertile habitats and suppressed the occurrence of mesophilous forest species, what, by contrast, decrease the species richness.
EN
We studied the species richness, diversity, abundance and guild composition of spider assemblages on the hummocks and in the hollows of the alder carr in the Białowieża National Park. We also assessed the effect of vegetation structure and soil humidity on spiders settled in these two microhabitats. The spiders were collected from 10 May until 27 October 2001 by pitfall trapping. The main factor which differed between the hummocks and the hollows was soil humidity. In the case of vegetation cover we found some differences between the microhabitats but it was particularly evident in the case of litter, which was higher on the hummocks. Spider species diversity was significantly higher on the hummocks than in the hollows, but the number of individuals captured in both microhabitats was similar. The collected spiders belonged to six guilds and the proportion of spider individuals in particular guilds was significantly different between the hummocks and the hollows. The most abundant guild in both microhabitats was ‘ground hunters’ and the most numerous species was Piratula hygrophila. Our analyses showed that soil humidity positively affected the number of spider species and the number of individuals. Sampling date strongly influenced the number of collected species and spider individuals. Vegetation and litter cover did not have a significant impact on the spider assemblages. Our findings suggest that research conducted only on hummocks in the alder carr does not reveal the real structure of spider assemblages.
EN
Habitat structure and selection by the Capercaillie Tetrao urogallus were assessed in the Augustów Forest (NE Poland), where a population of 50–80 birds and 11 active leks existed. Habitat preferences in the local scale were studied, based on measurements of total 1952 circular sample plots with radius of 15 m. On plots, in total, 10 variables describing forest structure (e.g. successional stage, canopy cover, vertical stand structure, share of Scots pine Pinus sylvestris, shrub layer cover, bilberry Vaccinium myrtillus cover, average height of ground vegetation, occurrence of feeding and roosting trees), as well as signs of Capercaillie presence, were assessed. Then, the model of Habitat Suitability Index (HSI) was constructed. Plots with high HSI scores were used by Capercaillie more often than expected in a case of a random choice, and those with low scores – less than expected. Capercaillie in the Augustów Forest prefers relatively old, one-layered stands, dominated by Scot pine with a sparsely developed shrub layer. The most important differences between abandoned and active leks were related to shrub cover in ground vegetation and height of ground vegetation and share of bilberry.
EN
The structural composition of the forest habitats is considered to be one of the most important factors affecting the breeding bird community composition. Structurally more homogenous forests are usually characterized by lower number of bird species and their densities. This study presents results of a comparison of the breeding bird communities in three Carpathian mountain forests, and the effect of the forest composition on breeding bird species richness and density. There are the bird communities occurring in semi-natural forests: natural mixed forest (NMF) - spruce-beech forest situated ca. 1000 m a.s.l. and UFZ-spruce forest in the upper forest zone (UFZ) up to 1510 m a.s.l., and the managed spruce forest (MSF) at altitude which is similar to NMF. The territory mapping method was used to estimate the number of breeding species and their densities during years 2004-2006. The species richness as well as the density of breeding bird communities were found to be higher in the semi-natural habitats (33 breeding species; 64.6 breeding pairs 10[^-1] ha in NMF and 28 breeding species; 57.6 breeding pairs 10[^-1] ha in UFZ) than in the managed habitat (21 breeding species; 53.6 breeding pairs 10[^-1] ha). This was true even for the high-elevated study plot despite the fact that the altitude is usually negatively correlated with both the species richness and density.
EN
European beech (Fagus sylvatica L.) ranks as one of the most adaptive species among European indigenous trees. Variable interactions between the trees and soil water depend on both phenotypic plasticity of the species and natural conditions. They are controlled through stomatal regulation and the ability of beech trees to accelerate quickly their growth if available resources increase. However, the effect of forest density at various altitudes on the soil water content in beech stands has been studied rather scarcely. Therefore, we monitored soil moisture by means of Time Domain Reflectometry in series of natural and managed stands located on sites representing the lower altitude (200-550 m a.s.l.), middle altitude (550-1050 m a.s.l.) and higher altitude (1050-1300 m a.s.l.) zones of the natural beech belt in the Western Carpathians, Slovakia. Forest stand density, expressed in terms of basal area, i.e. the sum of cross section areas of the tree stems at 1.30 m height, was unchanged in natural stands, but it was reduced by 60% in the shelterwood stands. In the clear-cuts, all trees were removed. Total soil water content (SWC) under forest stands was calculated in mm as the product of soil moisture and soil depth, the latter acquired by electrical resistivity tomography. SWC differences between natural and shelterwood stands of the lower altitude, middle altitude and higher altitude zones averaged 18 mm, 36 mm and -3 mm, respectively. According to the Friedman test on ranks, followed by post-hoc multiple comparison testing, the difference was only significant within the middle altitude zone. In it, soil water consumption by the natural stand was limited only by the hormonally controlled seasonal regulation. The comparatively low water loss in the shelterwood stand resulted from a small rainfall interception by forest canopy and a decreased soil water uptake due to reduced basal area, leaf area index and simple age-size forest structure. In the lower altitude zone, the precipitation deficit and limited extractability of soil water were responsible for the absence of larger SWC differences. As opposed to that, low potential evapotranspiration prevented any noticeable SWC differences within the higher altitude zone.
PL
Celem pracy było zweryfikowanie klasyfikacji nadzorowanej jako metody badania struktury gatunkowej i wiekowej drzewostanów w Rezerwacie Sieraków, Uroczysku Chojnów i Lesie Kabackim oraz ocena wykorzystanych materiałów. Ponadto zbadanie struktury kompleksów leśnych za pomocą wskaźników z ekologii krajobrazu. Do klasyfikacji, która była podstawową wykorzystywaną metodą, wzięto pod uwagę dwa trzykanałowe zestawy (TM2, TM3, TM4 oraz TM3, TM4, TM5) oraz pojedynczy kanał TM4. Określono klasy możliwe do wydzielenia na obrazach satelitarnych i na zdjęciach lotniczych. Dokonano wyboru pól treningowych i określono sygnatury spektralne poszczególnych gatunków i klas wieku. Wykonano klasyfikację nadzorowaną, korzystając z reguły największego prawdopodobieństwa. Uzyskano mapy, których dokładność określono, posługując się macierzą błędów i współczynnikiem zgodności kappa. Wybrano mapy sklasyfikowane z największą dokładnością i poddano je analizie z użyciem wskaźników z ekologii krajobrazu. Po przeanalizowaniu wyników sformułowano następujące wnioski: klasyfikacja nadzorowana obrazów Landsat umożliwia określenie składu gatunkowego i przedziałów klas wieku heterogenicznych kompleksach leśnych w sposób ogólny, skład gatunkowy jest możliwy do wydzielenia z większą dokładnością niż przedziały klas wieku, mimo położenia kompleksów leśnych w jednym regionie biogeograficznym nie można stworzyć jednolitych sygnatur spektralnych, błędy wynikają z uśrednionej informacji zawartej w pikselu, uogólnionych danych zapisanych na mapach drzewostanowych i opisach taksacyjnych, rozbieżności terminów wykonania zobrazowania i map, cyfrową analizę zdjęć lotniczych uniemożliwia zbyt szczegółowy obraz oraz jakość materiałów, które charakteryzują się znaczną zmiennością tonalną w zależności od położenia względem środka zdjęcia, wskaźniki opisujące strukturę drzewostanów ilościowo uzupełniają informację jakościową zawartą na mapach poklasyfikacyjnych, wyniki analizy ilościowej są uzależnione od rodzaju danych teledetekcyjnych.
EN
Forests are rich ecosystems, which fulfill significant functions as scientific, educational and finally recreational. Forest landscapes play a key role, particularly near urban areas like Warsaw, where they are affected by the town and its inhabitants. Collecting data about forests and analyzing it are desirable tasks for the purposes of environmental monitoring, protection, planning and management in different scales (spatial/time). Remotely sensed data proved to be very useful sources of information about forest characteristics as a specific ecosystem and as a part of the boarder landscape. The aim of this study is to present methods and techniques used for analyzing and effectively using satellite images and aerial photographs for certain purposes in forestry and environment protection. Analyses were made on the example of Landsat ETM+ satellite images acquired in 2000 and set of aerial photographs obtained in 1997 (PHARE, true color, 1:26000, 1:5000) and 1992 (color infrared, 1:10000). The areas under study are three forest complexes located near Warsaw: Kampinoski National Park, Chojnowski Landscape Park and Las Kabacki Reserve, which differ in size, diversity, and level of protection. Automated solutions in forest studies deliver objective and high quality thematic data, which are competitive to the conventional survey mapping methods.
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