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Both species-specific traits and landscape configuration, such as area and connectivity of habitat patches plus the character of uninhabitable matrix, affect animal movements in fragmented landscapes. Difficulties with disentangling species-specific and landscape effects have obscured comparisons among species, hindering the understanding of dispersal in metapopulations. To circumvent this complication, we performed a mark–recapture study of four related nymphalid butterflies within identical landscape and in single season. The studied species were three Melitaeinae checkerspots (Euphydryas aurinia, Melitaea athalia, Melitaea diamina) and one Argynnini fritillary (Brenthis ino). Applying the Virtual Migration model revealed that (1) except for mortality within habitat, model parameters differed from those found for the studied species elsewhere; (2) the three Melitaeinae species were more akin in movement parameters than the Argynnini representative (i.e., B. ino); (3) within Melitaeinae, differences between sexes were more prominent than differences among species; (4) Melitaeinae males left natal patches more readily than females, while the opposite applied to B. ino; (5) males of M. diamina and both sexes of B. ino exhibited highest values of dispersal mortality; (6) except for females of M. diamina and both sexes of B. ino, immigration and emigration scaled with area in females but not in males. Finding (1) demonstrates that geometry of habitat network affects mobility considerably and that transferring dispersal parameters across systems is unwarranted. Still, (2–6) demonstrate that within identical networks, related species follow similar dispersal patterns, suggesting that conservation scenarios suitable for a well-studied model species would suite related species as well.  相似文献   
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This study presents observations on the anatomical, palynological and ecological features of Tulipa gumusanica Terzio?lu and its morphologically similar relative, T. armena Boiss. var. armena, in order to clarify their similarities and differences. We found that these taxa have some important differences with regard to anatomical, palynological and ecological features, as well as morphological traits. General anatomical traits of both examined taxa are similar, both having isolateral leaves with distinct hypodermis and a stem with distinct monolayer collenchyma close to the epidermis. However, some anatomical characters such as mesophyll width, average number of stomata on lower epidermis, and epidermal cells on upper epidermis are found to be important in delimiting these taxa. In addition, considerable differences have been observed in pollen shape and size. The species differ ecologically in that T. gumusanica prefers slightly acidic soil with low organic content in the woodland, whereas T. armena var. armena prefers slightly alkali soil with high organic content in steppe vegetation.  相似文献   
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Data on the stratigraphy and development of a former lake near the town of Vracov, SE Moravia, Czechoslovakia, are presented. The infilling process and vegetation succession are described. An attempt to reconstruct changes in habitat conditions during the last ca. 13 000 years has been made.  相似文献   
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Interactions between methyl jasmonate (JA-Me) and ethylene in the photoperiodic flower induction of short-day plant Pharbitis nil were investigated. Both JA-Me and gaseous ethylene applied during the inductive long night caused a decrease in the number of flower buds generated by P. nil. Application of ethylene did not affected niether the level of endogenous jasmonates in the cotyledons during the 16 h long inductive night, nor the inhibitory effect of JA-Me on the flowering of P. nil accompanied by variations in ethylene production. The application of acetylsalicylic acid (aspirin)—a jasmonate biosynthesis inhibitor—slightly stimulated flowering. Our results have shown that the mechanisms of P. nil flower inhibition by jasmonates and ethylene are independent.  相似文献   
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