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.
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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.
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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.
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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.
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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.
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Carrion is an example of ephemeral and patchy microhabitat, rich in organic matter and therefore frequently colonized with a specific and repeated sequence by various arthropods. Beetles of the family Histeridae are a stable component of carrion communities, however their biology and ecology is poorly studied. Succession of insects on decomposing carrion may be used to determine elapsed time since death (so called post-mortem interval, PMI in forensic entomology). Recent studies have shown that some species of histerid beetles are highly useful for this purpose. However it requires detailed information on their biology, phenology and habitat preference. Seasonality, habitat preference and residency on carrion of histerid beetles were analyzed while studying succession of insects on 36 pig carcasses (mean weight = 25.8 kg) in spring, summer and autumn, in pine - oak forest, hornbeam - oak forest, and alder forest (2 carcasses/forest type/season/year). The experiment was conducted in the Wielkopolska region (Western Poland) in 2006 and 2007. The spring part lasted 88 days in 2006 and 105 days in 2007, the summer part - 49 days in both years and the autumn part - 94 days in 2006 and 105 days in 2007. Among 21 adult species recorded, Saprinus semistriatus (scriba), Margarinotus striola succicola (Thomson) and Margarinotus brunneus (Fabricius) were the most numerous. Moreover, larvae of Saprinus and Margarinotus were collected. Abundance (numbers per one carcass) of most adult species of Margarinotus was influenced both by the forest type and season whereas abundance of species of Saprinus was influenced only by the season. Most species reached the highest number of adults in spring. Only S. semistriatus was similarly abundant both in spring and summer. Larvae of Margarinotus were most abundant in spring, whereas larvae of Saprinus in summer. The majority of Margarinotus species reached their higher numbers in hornbeam - oak forest. Residency on carrion in adult S. S. semistriatus had a clear peak of abundance in spring (after 36 days of decomposition) and was shorter than residency in adult M. striola succicola and M. brunneus for which no clear peak was found. We suggest that differences in forest type preferences may result from differences in soil humidity and temperature near the forest floor, whereas differences in residency period on carrion between Margarinotus and Saprinus may be explained by differences in release patterns of volatile organic compounds (VOCs) attracting these genera.
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