Detailed knowledge of the circumstances behind the extermination of particular animal species is a key premise for their eventual return, reintroduction and ongoing preservation. Data on the presence of the Brown Bear (Ursus arctos) in the Czech landscape are usually limited to simple entries about the day and place where the last specimens in particular (usually mountainous) regions were slain. Demand for more precise data, especially regarding the last documented presence of bear cubs, has emerged in respect of the recently discovered ability of bears to migrate over long distances. The newly collected data allowed the author to present amuch more complete historical view of the process of extermination of the Brown Bear in the Czech territory. and Jan Andreska.
The prolonged survival of the Brown Bear (Ursus arctos) population in the Bohemian Forest was largely possible due to the protec tion of this animal, which was considered a rare and desirable trophy. Consequently the bear was able to survive in the Bohemian Forest for a hundred years longer than in the Ore Mountains. Isolated populations in the Sudetes survived in Moravia, and the last specimens were hunted down in the 1740s. Bears hunted down during the 19th century in the Beskydy Mts. can almost certainly be considered casual migrants from the Slovak part of this mountain range. The return of bears to the territory of Moravia and Silesia corresponds with the consolidation of the Slovak population due to the protection introduced in 1932. and Jan Andreska.
Large amounts of abandoned limestone quarries in the Bohemian Karst provide a great opportunity to study different stages of spontaneous succession simulta - neously. Molluscs are a suitable model group for this study –many land snail species including the rare ones occur in these quarries. Because of the large variability of habitats, quarries abandoned for around 60 years have higher species diversity. and Alena Kocurková, Lucie Juřičková.
Mesophyll conductance (gm) is essential to determine accurate physiological parameters used to model photosynthesis in forest ecosystems. This study aimed to determine the effects of time of day on photosynthetic parameters, and to assess the effect of using either intercellular CO2 concentration (Ci) or chloroplast CO2 concentration (Cc), on maximum carboxylation velocity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), Vcmax. We used Amazonian saplings of Myrcia paivae and Minquartia guianensis. Photosynthetic parameters were measured using an infrared gas analyzer (IRGA); gm was determined using both gas exchange and chlorophyll (Chl) a fluorescence and gas-exchange data alone. Leaf thickness (LT) and specific leaf area (SLA) were also measured. Air temperature, relative humidity or understory light did not correlate with gm and on average daily IRGA-fluorometer-determined gm was 0.04 mol(CO2) m-2 s-1 for M. paivae and 0.05 mol(CO2) m-2 s-1 for M. guianensis. Stomatal conductance (gs), gm, electron transport rate (JF), and light-saturated net photosynthetic rate (PNmax) were lower in the afternoon than in the morning. However, no effect of time of day was observed on Vcmax. LT and SLA did not affect any of the examined parameters.
IRGA-determined g m was almost the double of the value obtained using the IRGA-fluorescence method. Vcmax values determined using Cc were about 25% higher than those obtained using Ci, which highlighted the importance of using Cc in Vcmax calculation. Decline in PNmax at the end of the afternoon reflected variations in gs and gm rather than changes in Vcmax. Diurnal variation in gm appeared to be associated more with endogenous than with atmospheric factors. and H. C. S. Nascimento, R. A. Marenco.
The elected large cave spider Meta me nar - di occurs throughout the Palaearctic re - gion. In Central Europe, it is usually found in upland regions, and is particularly common in karst areas. The spider lives in subterranean caves, cellars, mineshafts and stone runs. and Milan Řezáč.
The Asian ladybird Harmonia axyridis is an invasive insect in Europe and the Americas and is a great threat to the environment in invaded areas. The situation is exacerbated by the fact that non native species are resistant to many groups of parasites that attack native insects. However, very little is known about the complex microbial community associated with this insect. This study based on sequencing 16S rRNA genes in extracted metagenomic DNA is the first research on the bacterial flora associated with H. axyridis. Lady beetles were collected during hibernation from wind turbines in Poland. A mean ± SD of 114 ± 35 species of bacteria were identified. The dominant phyla of bacteria recorded associated with H. axyridis were Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. Representatives of these phyla are common in the environment, e.g. in the soil, and are often identified as the dominant bacteria associated with arthropods. We also identified animal pathogenic bacteria, such as Burkholderia, Rhodococcus, Chlamydiae and Anaplasmataceae spp. (Neorickettsia helminthoeca and Ehrlichia ovina). We also identified Wolbachia pipientis in a single beetle. This bacterium is a causative agent of reproductive alterations in arthropods. These results support the enemy release hypothesis in the case of this ladybird invasion. Pathogenic bacteria were recorded in only a few samples. Moreover, male-killing bacteria such as Spiroplasma spp., Wolbachia spp. and Rickettsia spp. were only recorded in single insects so they cannot be responsible for the observed alterations in the sex-ratio of the ladybird population studied., Krzysztof Dudek, Kinga Humińska, Jacek Wojciechowicz, Piotr Tryjanowski., and Obsahuje bibliografii