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The aim of the present study was to determine the yearly mortality level and identify the collision places of mammals on a road network with varying traffic volume, as well as to establish the main relations between habitat structure and the number of roadkills. During 26 months of survey on a 48.8 km road network (15 roads) with different traffic volumes (350– 10500 cars per 24 h) situated in an agricultural landscape of SW Poland 383 killed mammals of 23 species were found. The most abundant group were small rodents (40%), with dominant common vole Microtus arvalis (26%) followed by insectivores (32%), topped by two species of hedgehogs Erinaceus spp. (20%). The average (± SD) road-kills index during the whole study period on 11 road sections with the lowest traffic volume (350–460 cars per 24 h) amounted to 0.29 ± 0.14 (range = 0.08–0.56) casualties per 100 m. This value was over seven times lower than on the section with the highest (10500 cars per 24 h) traffic volume (2.13 casualties per 100 m). Over 80% of victims were found between May and October. During the whole study period 38% of victims were recorded within built-up areas, where 26% of the studied roads were localized. The other 62% were found on the roads situated in the open farmland (74% of all roads). The clear majority of hedgehogs Erinaceus spp., weasels Mustela nivalis, brown rats Rattus norvegicus, beech martens Martes foina and red foxes Vulpes vulpes died within villages, while the animals killed on roads in the open farmland included all recorded common voles, moles Talpa europaea and common shrews Sorex araneus. The decisive factor affecting the mortality level in mammals in the multiple regression model was the daily vehicle traffic volume. This variable had significant, positive influence on the number of victims both within the most abundant species, their groups (insectivores, rodents, mustelids), as well as all mammals. The road location in the open countryside was an additional factor affecting the level of losses in rodents, while its presence in the built-up area increased the mortality of hedgehogs.
Elephants were confined to Mengyang Protected Area in China and their distribution range had reduced greatly compared to past records. A preliminary study of habitat selection by Asian elephantsElephas maximus Linnaeus, 1758 and their distribution was conducted in Mengyang Protected Area and its surrounds using site visits and transect surveys from July 2003 to December 2006. Although no variable significantly influenced their habitat selection, elephants still showed preference for altitudes between 900 and 1200 m, gradients <30°, and orientations to the south-east, south and south-west. Human activities, including habitat transformation and degradation, disturbance by large infrastructure and poaching were considered to be the main factors inducing elephant distribution changes.
During four seasons (years 2000–2004) on 52.3 km of roads with traffic frequencies ranging from 350 to 10 500 vehicles day⁻¹ and crossing diverse habitats in five regions of south-western Poland 3 742 roadkills from 10 amphibian species were recorded. The most frequent road killed species was common toad Bufo bufo (52% of all roadkills), followed by common frog Rana temporaria (12%), green toad Bufo viridis (11%) and moor frog Rana arvalis (3%). For all surveyed roads the roadkill density was positively correlated with the share of woods and the area of ponds. Actual traffic density was a poor predictor of the number of amphibian roadkills in large landscape scale (all surveyed roads). To assess the factors affecting the number of amphibian roadkills in the small landscape scale the Generalized Linear Models (GLZ) were performed between the number of casualties and five habitat variables (area and number of ponds, share of builtup area, open countryside and woodland) for four circular buffer zones (<200 m, <300 m, <400 m, <500 m) around each of the 100-meter sections within 1.8 km of road crossing an area rich in water bodies. The most important variables in GLZ models were the area and number of ponds. These predictors had statistically significant impact on number of roadkills within buffer zones <500 m (area of ponds) and <400 m (number of ponds).
The study examine s the vegetation diversity (235 herbaceous species) in variable road-site types in terms of life history components (life traits) like life form, type of pollination, seed dispersal, spreading ability, life strategy according to Grime’s classification, and in terms of habitat preferences using Ellenberg’s indicator value (in relation to light, temperature, moisture, nitrogen, soil pH and soil salinity). Plants registered as alien species were evaluated also according to invasive status, level of abundance, introduction mode and land use habitat. Study localities (9 sites) were situated in the Českomoravská highlands and the South Bohemian regions (Czech Republic). The plant species were recorded in the bands (width in range of 1.5–3.0 m) along the verge of two types of roads (motorways with median stripes) and secondary roads (II and III classes). In total – road length of about 15 km and the total area of roadside vegetation of about 8 ha were surveyed. The annual/therophyte species with a tendency to seed dispersed by wind, preferring a light and dry habitat, and having the RC (competitive-ruderal) life strategy were mainly found along the motorways. It means that road verges along motorways are quite insolated and constitute the dry habitats, probably suitable for ruderal, weedy, non-native, and invasive species. On the contrary, species with a tendency to vegetative reproduction and the C (competitive) strategy occur mainly along the secondary roads. It seems that the secondary roads are alternative habitats for grassland flora. Species occurred on the verges of the secondary roads do not belong to the particular group of the life traits. The salt tolerant species Puccinellia distans (Jacq.) Parl. was found along all types of roads. Almost 24% of all recorded herbaceous species growing in road-sites were alien species.
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