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2. Effect of disturbance on the vegetation of peat bogs with Pinus rotundata in the Třeboň Basin, Czech Republic
- Creator:
- Bastl, Marek, Štechová, Táňa, and Prach, Karel
- Type:
- article and TEXT
- Subject:
- bark beetle, bog pine, bryophytes, fire, peat harvesting, regeneration, species composition, succession, vascular plants, and windthrow
- Language:
- English
- Description:
- Various stages in the succession of vegetation of peat bogs following disturbance were studied in the Třeboň Basin, Czech Republic. The disturbance was of two types: (a) natural, represented by windthrow, with subsequent bark beetle attack, and fire, and (b) human-made peat digging and industrial peat milling. The species composition at different stages in succession following disturbance were compared with that in undisturbed plots. Regeneration of peat bog vegetation was faster after a natural than after human-made disturbance. The lowest impact was caused by windthrow, followed by fire. Regeneration after peat digging took much longer. Regeneration after industrial peat harvesting only occurred if the groundwater table level remained high.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
3. Fine fluorescent powder marking study of dispersal in the spruce bark beetle, Ips typographus (Coleoptera: Scolytidae)
- Creator:
- Petr Doležal, Okrouhlík, Jan, and Davídková, Markéta
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, kůrovcovití, lýkožrout smrkový, Scolytidae, Ips typographus, Coleoptera, bark beetle, dispersal, fluorescent powder, chráněná území, 2, and 59
- Language:
- English
- Description:
- A novel method was used to study dispersal in the spruce bark beetle, Ips typographus (L.), under epidemic conditions (rapidly increasing population density) in the Šumava National Park. Infested spruce logs were coated with a fine fluorescent powder and the passively marked emerging beetles were captured in pheromone baited traps located at various distances from these logs. The number of marked beetles captured decreased exponentially with increasing distance from the release point. The sex ratio of the bark beetles was more female biased the further they were recaptured from the logs, being 57% and 60% at distances of up to 50 and 100 m, respectively. The maximum distance flown by a marked beetle recorded in this experiment was 1094 m. A model fitted to the data on dispersal indicates that 10% of the spruce bark beetles dispersed over distances of 55 m and 4 m in spring (overwintered parental generation) and summer (first filial generation), respectively. Differences between spring and summer swarming are briefly discussed., Petr Doležal, Jan Okrouhlík, Markéta Davídková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Unikaryon montanum sp. n. (Protista: Microspora), a new pathogen of the spruce bark beetle, Ips typographus (Coleoptera: Scolytidae)
- Creator:
- Weiser, Jaroslav, Wegensteiner, Rudolf, and Žižka, Zdeněk
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Microspora, Unikaryon, bark beetle, ips, and Central Europe
- Language:
- English
- Description:
- Unikaryon montanum sp, n. infects the fat body, muscle, Malpighian tubules and ovaries of adult Ips typographus L. The development is haplokaryotic, with separate nuclei during the schizogony and sporogony. Sporonts have the cellular envelope with added layer of electron dense material. Two types of spores are formed: small broad-oval primary spores, 1.5 x 1.0 pm, with warty surface of spore wall, uninucleate, with isofilar polar filament in 5/6 coils and elongated-oval environmental spores, 0.8-1 x 2 pm, with warty spore wall attenuated at the anterior end, uninucleate, with spore polar filament in 8 coils. Both types have a dual polaroplast with the anterior part of a layer of confluent fine lamellae ending posteriorly in bulbous processes, and posterior part composed of coil of tubules.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public