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The morphology and chaetotaxy of the rediae and the cercariae of Isthmiophora melis are described and compared with other echinostomatids and related groups of trematodes. Apart from adult morphology of I. melis, which is typical of Echinostomatidae, the structure of the redia and chaetotaxy pattern of the cercaria are the most similar to those observed in an echinostomatid genus Paryphostomum as well as in representatives of the family Cathaemasiidae, especially in Cathaemasia hians.
To explore and describe the species richness patterns along altitudinal, high mountain gradients, two transects – northern exposure (YG) and southern exposure (TD) at Mt. Jiuding (1200–4200 m) in Western China (31º13’– 31º46’N, 103º29’–104º05’E) were selected. They differ from south to north in climate conditions and vegetation zonation, and each transect was sampled according to a uniform method. Every 200 m along the altitudinal gradient we set a sampling belt of 3000 m × 5 m to record the tree species, and 30 plots of 5 m × 5 m within every vegetation belt were used to investigate shrub and herb species. We compared the composition of plant species and calculated the coefficient of similarity between the two transects. A Generalized Additive Model (GAM) was used to describe the richness patterns. For the whole Mt. Jiuding, the richness at all three levels (species, genus and family) showed a monotonically decreasing pattern. As for the different growth forms, richness of the trees, shrubs and pteridophytes showed hump-shaped patterns; and herbs showed a slow decreasing pattern along the altitudinal gradients. In TD transect, the richness of species, genus and family also showed monotonically decreasing patterns; tree richness decreased with the increase of altitude; the shrub richness showed a humpshaped pattern; but pteridophytes and other herbs showed wave-like patterns. In YG transect, altitudinal gradient of richness at different taxonomic levels all showed hump-shaped patterns; and the species richness patterns for different growth forms peaked at middle attitude except for the graminoids and other herbs. The evolutionary history of the vegetation in Mt. Jiuding was quite consistent, and different richness patterns along altitudinal gradients might be resulted from different contemporary ecological conditions. Human disturbance and different range of altitudinal gradients were also important factors for different richness patterns between the two transects. In our study, species in different growth forms showed different altitudinal patterns, but those species with similar requirements to environmental conditions showed similar richness patterns along altitudinal gradients.
Use of resting sites by 14 radio-tracked pine martens Martes martes (Linnaeus, 1758) (6 males and 8 females) was studied in Białowieża National Park, northeastern Poland. Males used, on average, 191 different resting sites throughout the year while females used 159 sites. The reuse index varied from 0.07 to 0.94 and it was highest for females with young in spring and lowest for both males and females in summer, in autumn-winter, reuse of resting sites by males decreased significantly (p = 0.006) in deep snow cover and it increased (p = 0.021) when marten's ate more ungulate carcasses. In spring, the reuse index for males was negatively correlated with the mean ambient temperature during the tracking period (p = 0.019) and did not depend on rodent abundance. In spring and autumn-winter, most individuals used resting sites which were randomly distributed in their home ranges. In summer, resting sites of males were clumped and were located near the edges of their home ranges, close to females' home ranges. The average distance between consecutively used resting sites was significantly higher for males (690 m) compared to females (419 m, p < 0.001). In spring and autumn-winter (but not in summer) the average distance between the male resting sites depended on their body mass. For males, temperature had significant influence on the pattern of resting site choice for the following day, while for females this relationship was not found. Individuals of the same sex and overlapping home ranges did not use the same resting sites in the same season, except for a young male and an old female that were found in one resting site at the same time from mid-June to mid-August.
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