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EN
The studies were conducted in the summers of 2017 and 2018 on three watercourses in Central and North-Western Poland, the where maintenance works involving disposal of sediment and silt were performed in the autumn of 2017. Monitoring of the ichthyofauna in the Rurzyca River and the Tywa River before (year 2017) and after the maintenance works (year 2018) indicated a decrease in the number of species. Altogether, 23 fish species were caught in all the watercourses. Out of these, 12 species were not recorded after the studied rivers had been dredged. A slight decrease in the number of fish species was observed in each studied river after the maintenance works. The values of physicochemical parameters obtained for each watercourse indicate a low quality of the waters. After silt had been removed from the watercourses, lower N-NO3values were observed at most research sites, whereas the N-NH4+ values increased significantly (except for one site on the Kanał Habdziński). Additionally, high volumes of P-PO43-were observed (except for sites 2 and 3 on the Kanał Habdziński and site 2 on the Rurzyca River). Maintenance works performed on small watercourses have a negative impact on the quality of waters and a less significant impact on the number of fish and biodiversity. This appears to be connected with migration of fish in the river during the maintenance works and avoidance of the consequent unfavourable conditions to gradually return to their habitats afterwards.
EN
This study evaluates and compares habitat preferences and spatial niche breadth and overlap between two sympatrically occurring species, the sand cat (Felis margarita) and Rüppell's fox (Vulpes rueppellii), in a desert landscape of central Iran. A field survey from 2014 to 2016 was conducted to collect occurrence points for the two species as well as to identify their structural characteristics of used habitats in the occurrences points. Jacobs' index as a measure of habitat preference, Shannon and Levins' indices as measures of niche breadth, MacArthur, Levins and Pianka's indices as measures of niche overlap were calculated and interpreted. The results of this study showed that the sand cats are specifically restricted to sand dune and sabulous habitat type, whereas Rüppell's foxes have wider ecological amplitude. Sand cats only prefers sand dunes while Rüppell's foxes were found to prefer foothills, badlands, and sand dunes. Rüppell's foxes therefore had a wider niche breadth compared to the sand cats. The asymmetric MacArthur and Levins indices yielded a higher value of niche overlap for the sand cats compared to Rüppell's foxes, while the symmetric Pianka's measure of niche overlap was relatively high for both species. Such habitat preference and niche segregation between the two species may be a result of their feeding habits or the physical protective structure of their habitats attributes.
EN
The small mammal species were investigated in the urbanized environment of Nitra city (Slovakia) in a multiscale-approach: at habitat level and at landscape level (urban-rural gradient). Continuous comprehensive rodent samplings from 2012 to 2015 were conducted in ten study sites, classified into three urban zones (landscape level). The total effort comprised 1,250 specimens of 13 species (Microtus arvalis, Apodemus sylvaticus, A. flavicollis, A. uralensis, Clethrionomys (Myodes) glareolus, M. subterraneus, Micromys minutes, Mus spicilegus, M. musculus, Crocidura suaveolens, C. leucodon, Sorex araneus, S. minutus) gathered in 14950 trapxnights. Environmental variables (habitat level) at each site were processed in the Geographical Information System as a proportion of landscape units around the trapping line and by a phytosociological survey. At the habitat level, we found a relationship between the landscape habitat structure and each species of small mammals. Diversity, species richness and relative abundance of small mammals decreased with the density of the built-up area. At landscape level, urban zones had a significant influence on species diversity, richness and relative abundance of small mammal populations. On the other hand, the presence of small mammal species precisely determined the urban zones, where we identified seven indicative species.
EN
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.
EN
The prediction of species response to human activity is of great interest in contemporary restoration ecology. The purpose of the article was to analyse which species life history traits and species habitat preferences are important during succession after the abandonment of mining activity in a sand-pit. During a 15-year period (1996–2010), 176 phytosociological relevés were placed within vegetation patches of different ages and divided according to soil moisture, thus forming two series of chronosequences that ranged from 0 to ca. 50 years. The datasets were analysed using both DCA/CCA ordinations and regression trees. The successional gradient, apart from the theoretically predicted replacement R by C strategists, revealed the occurrence of stresstolerant ruderals and competitive ruderals in the early successional stages. However, differences were observed between the wet and dry series. On dry soils the ruderals, anemochorous and windpollinated species dominated in the early phases. In the middle successional phases, a preponderance of anemochorous species (nanophanerophytes, light or semi-shade demanding species), nitrogen-poor and competitive ruderals or species typical for nitrogen-rich soils was recorded. In the late successional stages, species with both the ability of vegetative and generative reproduction appeared. On the other hand, on wet sites in the early successional phases, species with vegetative growth, hydrophytes, chamaephytes and stresscompetitors prevailed. Later in the succession, they were replaced by insect-pollinated species in nitrogen rich habitats and stress-tolerant ruderals on less fertile habitats. Finally, competitors started to prevail. Knowledge of the environmental conditions of a given site, the ecological processes and species biology can assist in achieving the desired goals or in initiating or enhancing succession on some disturbed sites.
EN
In total 273 stands of the invasive species Fallopia (Reynoutria) japonica in Oświęcim valley (southern Poland) were examined, in terms of cover, area, abundance, height and width of shoots, and presence of coexisting species. F. japonica occurred more frequently in wastelands and was the rarest in forests. Statistical analyses revealed some significant differences among habitats with particular traits. The most abundant populations, occupying the largest area, were recorded in wetlands and along railway lines. Populations were very diverse in terms of their percentage of flowering shoots within a particular type of habitat, however, the highest percentage was again observed in wetlands and along railways. In forests, gardens and in wastelands the contribution of flowering shoots was lower. The presence of accompanying species in the studied populations was generally low, most frequently stands of F. japonica were mono-specific with a slightly higher cover of accompanying species being recorded in F. japonica populations in forests. The highest proportion of the tallest shoots within a patch of F. japonica was observed in wetlands, while the lowest was in wastelands and in railways. The individuals with the thickest shoots were present in forests and wetlands and the thinnest in wastelands. Despite the simplified nature of the data collection the study demonstrated that F. japonica is more vigorous and forms larger stands occupying larger areas in some of the analyzed habitats. The study showed that in manmade habitats the considered species has favourable conditions for its development and further spread and this is of concern to conservationists and land managers as it can pose a threat to native biodiversity.
EN
Larvae and adults of some generalist insect species co-occur in identical habitats whereas adults and larvae of other generalist species do not co-occur and occupy different habitats. The Meadow brown, Maniola jurtina (L.) (Lepidoptera: Nymphalidae), is common and widely distributed in Europe where it is considered a habitat generalist. As knowledge about the occurrence of the larvae of the Meadow brown is scarce (different and more difficult methods are needed to collect larvae compared to adults) a complex assessment of the life strategy of this generalist is limited. We addressed here the question as to whether the adults and larvae of the Meadow brown co-occurred in the same habitats and how they depended on the type of grassland vegetation and habitat management. We expected co-occurrence of adults and larvae and similar effects of habitat management on them. We selected four habitat types belonging to the alliance Arrhenatherion elatioris W. Koch 1926, which form mosaic patterns in the rural landscape of central Slovakia: (1) extensive meadows mown once a year, (2) extensive meadows mown twice a year, (3) abandoned meadows, and (4) ecotones between deciduous forests and meadows mown once a year. Adults were counted in each habitat on seven transects 50 m long (in seven replicates) during the summer of 2003, 2004 and 2005. Larvae were collected in each habitat on 10 transects 50 m long (ten replicates) by sweeping vegetation (60 sweepings per transect) at night in May 2005 and 2006. Both adults and larvae occurred in all the mentioned types of habitats. A high abundance of adults and larvae was recorded in extensive meadows mown once a year and in ecotones. The lowest abundance of adults and larvae was found in abandoned meadows. The differences between abandoned meadows and ecotones (in the case of adults) and between abandoned meadows and extensive meadows mown once a year (in the case of larvae) were significant in all study years (P <0.05; multiple comparisons, K-W ANOVA). In the abandoned meadows the number of adults and larvae (median) was approximately 2 to 5 and 5 to 25 times lower than in the preferred habitats, respectively. Maximum numbers of both adults and larvae per single recording/sampling date were obtained in extensive meadows mown once a year; that is 185 adults in a transect 350 m long and 4 m wide and 267 larvae in the transect 500 m long (600 sweepings). Hence, similar to adults, larvae tend to be habitat generalists. Our results have confirmed the "advantageous" life strategy of M. jurtina which enables the species to adapt to a wide range of habitats, including those under strong pressure from humans. Comparing management practices in the study habitats, meadows which are mowed once a year were the most appropriate alternative for this species.
EN
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.
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