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In this study, eight forest associations in Szczecin Landscape Park and in the vicinity were examined for the presence of ant species. The only species present in all the associations was Myrmica ruginodis. Habitat conditions in the beech forest (Galio odorati-Fagetum), which grows on post-glacial hills, was diversified enough to enable occurrence of as many as 16 ant species. There was no substantial difference in ant species composition between beech and mixed forests. Alder swamps and riparian forests seemed to provide unfavourable living conditions for ants and only 3 ant species were recorded in these environments. Results show that indicating the type of plant association alone may be insufficient to characterize the environmental conditions that affect ant occurrence.
In this paper we introduce a new way of analysing habitat preferences of plant communities using the genotype and genotype-by-environment interaction effects (GGE) biplot method. We took into consideration real data on six plant associations belonging to the Molinio-Arrhenatheretea class. A total of 241 phytosociological relevès collected with the Braun-Blanquet method were described by the Ellenberg indicators. The two-way classification relevès-by-indicators was analysed with GGE. As a result it is proposed the modified biplot that contains ellipses for making the plot clearer. Next, we present the equations that described both axes and allow adding into the biplot any other relevès or a mean of set of relevès. Based on the generated biplot it is possible to present an ecological characteristics of any type of plant community including its acceptable and typical habitat requirements. The ellipse ranges provide important information about the homogeneity and ecological spectrum of the analysed syntaxon. The constructed equations allow comparing new data with data analysed previously. Summing up, the GGE biplot method is useful for analysing and graphically presenting ecological preferences of plant communities in a simple and comprehensive way.
The spread of species far from their native range is an important component of global changes. Investigating the ability of alien plants to invade different habitats is one of the most important approaches in the analysis of biological invasion mechanisms. The study was based on floristic research carried out in 1998–2002 in the north-western part of Poland. The habitats sampled were classified according to the EUNIS classification. A dataset of 2638 naturalized neophyte records was compiled based on a total of 2132 floristic lists. Species entries were supplemented with data on taxonomic position (family), origin, frequency, life form and number of habitats a particular species colonises. Ordination analyses showed the level of disturbance in individual habitats to be important in species-habitats relationships. Some of the species (e.g. Chamomilla suaveolens, Galinsoga parviflora, Veronica persica) occurred mainly in man-made, heavily disturbed habitats, while others (e.g. Impatiens parviflora, Padus serotina, Quercus rubra) were present primarily in natural habitats, less affected by humans. The species with the broadest habitat ranges identified included, i.a. Conyza canadensis, Impatiens parviflora, Epilobium ciliatum, and Oxalis fontana. Most of them, however, had different “core” habitats. Some species, e.g. Juncus tenuis, Elodea canadensis, Veronica persica were associated with one or a few habitats. The ability of species to invade numerous habitat types did not depend on their invasive status. The most successful aliens are those which spread dynamically along forest paths as well as those penetrating forest communities. The phytocoenotic role of each naturalized neophyte in plant communities requires a detailed study. Each individual habitat supports well-established alien species whose traits fit its characteristics and the disturbance intensity. Analysis of alien species traits, local distribution, habitat preferences and range makes it possible to reliably assess potentially successful invaders.
Post-industrial sites form a unique phenomenon in the landscape. They enable us to study the human-altered succession of communities. Regarding this, we studied an ant community in three types of habitats – reclamation and spontaneous succession in an ore basin together with unaltered surroundings in the Czech Republic. More than 30 years after being abandoned, the site with spontaneous succession was more species rich than the reclaimed one. Moreover, spontaneous succession created a habitat that was more similar regarding ant diversity to the unaltered surrounding environment than that after traditional reclamation. Ants dependent on tree vegetation were rather rare in both the reclaimed and spontaneous succession parts of the ore basin compared to the surrounding landscape. The relative abundance of socially parasitic ants increases in a gradient from the reclaimed basin, through the basin with spontaneous succession to the unaltered surroundings. Our study highlighted the fact that the formation of ant communities at post-industrial sites is clearly more complicated than for other arthropods, including related aculeate hymenopterans. The potential of both reclaimed and spontaneous succession basins for harbouring endangered species appeared to be lower for ants than for other taxa indicated by recent studies.
Saproxylic beetles are essential for the proper functioning of forest ecosystems. However, intensive forest management has led to the disappearance of suitable microhabitats of many species associated with dead wood. Cucujus cinnaberinus is an endangered saproxylic beetle which develops under the bark of dead wood. The species usually occurs in protected areas, however, some populations inhabit long-term managed forests in Central Europe. In this study, we analyzed the effect of nine silviculture-related and decay-related factors on the C. cinnaberinus microhabitat selection in managed forests. We found that potential sun exposure, bark thickness, dead wood moisture and the hardness of dead wood have a significant effect on the C. cinnaberinus microhabitat selection. The species prefers sun-exposed dead wood with thicker bark at an intermediate stage of decay with undecomposed xylem, but avoids completely dry pieces. Furthermore, we found no confirmation of a direct connection between dead wood diameter and the occurrence of C. cinnaberinus. We stressed that logging residues or stumps are mostly unsuitable for C. cinnaberinus development.
The habitat preferences of red foxesVulpes vulpes (Linnaeus, 1758) in Bristol, UK, were compared during periods of high and low population density following an outbreak of sarcoptic mange (Sarcoptes scabiei). These periods are termed ‘pre-epizootic’ and ‘post-epizootic’, respectively. Habitat preferences were compared between periods during nocturnal activity and diurnal inactivity using compositional analysis. Back gardens were the most preferred habitat for pre-epizootic foxes during periods of activity; back gardens and allotment/woodland habitats were equally preferred by post-epizootic foxes, with a trend for allotment/woodland to be the most favoured. During periods of inactivity, pre-epizootic foxes selected back gardens for diurnal rest sites, compared with allotments/woodland in the post-epizootic period. Post-epizootic foxes also showed a significant decrease in rest sitefidelity, such that they were very unlikely to re-use a rest site more than once. In comparison, pre-epizootic foxes were often very faithful to one or a small number of sites. Such changes in habitat preference and rest site fidelity could have been facilitated by: (1) changes in food availability, (2) a decrease in intra-specific competition, (3) the requirements of defending larger territories post-epizootic, or (4) an avoidance of habitats that might increase the likelihood of mange transmission. The management implications of these results are discussed.
Studies on the relationship between habitat heterogeneity and animal abundance are essential for understanding what determines biodiversity. Transect-based direct observations of eight principal prey species of tiger in the Chitwan National Park (CNP) were used to determine their abundances and habitat preferences. Chital was the most abundant prey species of tiger (Panthera tigris). Each of the prey species had significantly different habitat preferences except sambar deer and chital. Habitat preference was measured using Manly’s preference index, which revealed that short grassland, mixed forest, and riverine forest were the most preferred habitats of the prey species. The results indicate that large species of deer tend to be found in more diverse habitats than small species, except muntjac. The abundance of the principal prey species of tiger was positively correlated with habitat heterogeneity. The habitat, which contributes significantly to the heterogeneity of the landscape, is grassland in large patches of forest. The ongoing increase of forest cover in the CNP has led to a reduction in the area of grassland, which may negatively affect the abundance of the prey species of tiger. Hence, it is suggested that the restoration of landscape heterogeneity is the best way to manage the habitats in the CNP.
We compared the habitat preferences of the alien raccoon dog Nyctereutes procyonoides (Gray, 1834) and the native badger Meles meles (Linnaeus, 1758) in two areas (Ruissalo and Tuulos) in southern Finland by radio-tracking the animals during summer from 2005 to 2008. We assumed that the habitat preferences of these two medium-sized carnivores differ to some extent (ie they are able to share the resources), because they have been sympatric for more than 50 years in southern Finland and populations of both species have increased during that period. The results indicated that the habitat preferences of these species are indeed different: raccoon dogs favoured meadows, gardens and open woodlands with tall and abundant undergrowth, whereas badgers favoured both pine forests and deciduous and mixed forests with thick canopy but sparse undergrowth. However, fields were favoured by both species in one study area (Tuulos). The results show that although both species are flexible in their habitat use and share some habitat preferences, the most favoured habitats differ between the species.
During seven winter seasons (1993/1994-1999/2000) 107 roadside counts (28 km each) in agricultural area of south-western Poland were conducted. From among 1526 Buzzards, 1293 were recorded in winter months (November-February) and 233 in March. Birds were non-randomly distributed on nine vegetation types met along the transect route. Permanent papilionaceous crops, along with cereal stubbles, margin habitats, meadows and maize stubbles were preferentially used, whereas bare tillage and winter cereals were avoided. In general, Buzzards preferred habitats of the least amount in the studied area and avoided those which dominated. These data support the idea of high importance of small landscape structures for the biodiversity protection in intensively used farmland. During winter months, most Buzzards (59.5%) were perched when first sighted, most often on trees and in the middle part of their height. The percent of birds sitting on the ground amounted to 34.7%. The smallest amount of individuals (5.8%) was observed flying (flap-sailing, hovering and soaring), however this activity significantly increased in March (up to 17.1%). The significance of various hunting methods for wintering Buzzards is discussed. Even though it is a typical perch hunting raptor, the method of hunting from the ground seems to be particularly suitable for the conditions of winter farmland: common scarcity of perches, poor and low vegetation, local and temporary prey concentrations.
The Grayling Hipparchia semele L. belongs to rapidly vanishing butterfly species in its central and western European range. We studied larval microhabitat preferences of two last viable populations of the Grayling in the Czech Republic. The field study was carried out at two types of human-influenced habitats: a fly ash deposit — a postindustrial site partly left under natural succession processes, and a semi-natural extensively grazed xeric calcareous grassland in May and June 2012 and 2013. During five nights, 89 caterpillars were found (fly ash deposit: 8, xeric grassland: 81). The caterpillars were found on steeper slopes covered with sparse shrubs and shorter herbaceous vegetation with high amount of bare soil or rocks. The most frequently observed behaviour was feeding on fine-leaf fescue grasses with varied size of tufts and rather smaller height up to 20 cm. Usage of larval preferences in a way of active conservation management application is discussed.
Analysis of 531 nest cards (Polish Nest Record Scheme) of the Great Spotted Woodpecker, obtained in the years 1970–2003 is presented here. The data is derived from almost the whole of Poland, except for the Białowieża National Park. From the material processed for the purpose of this study, the Great Spotted Woodpeckers appear to nest in various types of wooded habitats, especially in forests and they are very flexible in their choice of nesting sites, both in terms of age of tree stands and intensity of human penetration. As a rule, woodpeckers breed mostly in holes made in deciduous trees (oak, birch, and alder). More than 95% of nests were excavated in tree trunks, primarily in dead or weakened trees. Woodpeckers excavated their nest in the range of 0.5–19 m above the ground, with more than 75% of them found in the narrower range from 1–7 m. The height of cavity above the ground did not depend on tree species or vegetation type and was also weakly correlated with the height of tree stands. The openings of cavities showed no statistically significant differences in their geographical orientation. Although the information about woodpecker nests, gathered in the Nest Record Scheme does contain certain errors (such as “habitat preferences” of observers), the obtained results provided a better insight into the nesting ecology of this species in Poland.
Even though Alliaria petiolata is a globally important invasive plant, for Europe it is a native humble understory species. I studied the population characteristics of A. petiolata in its native range (NE Slovenia) by evaluating its demographic structure (e.g. population size, density, plant fruit production) and herbivory damage in different habitats (forest understorey, forest edge, ruderal site). Moreover I tested the allelopathic potential of fresh A. petiolata leaves and roots on garden cress Lepidium sativum germination and seedling development. I performed bioassays with aqueous extracts and took a first step toward testing the presence of volatile potentially allelopathic compounds. The results showed that A. petiolata populations can become established at disturbed sites, even such without a tree canopy, but dense stands can be found only at disturbed forest edges. The bioassays confirmed the presence of A. petiolata aqueous and volatile allelochemicals in leaves and roots. Germination was suppressed more by volatiles, showing that allelopathy can act via volatile compounds and further suggesting their antifungal effects. The results allow predicting that the success of A. petiolata invasion in a non-native range might rely on its variable habitat tolerance (not being a strict ruderal species) and allelopathy.
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