• MeSH
• Francisella tularensis izolace a purifikace   MeSH
• Hantavirus izolace a purifikace   MeSH
• hlodavci krev   mikrobiologie   MeSH
• infestace klíšťaty epidemiologie   mikrobiologie   MeSH
• viry klíšťové encefalitidy izolace a purifikace   MeSH
• zdroje nemoci MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Geografické názvy
• Slovenská republika MeSH

Forests are increasingly affected by natural disturbances. Subsequent salvage logging, a widespread management practice conducted predominantly to recover economic capital, produces further disturbance and impacts biodiversity worldwide. Hence, naturally disturbed forests are among the most threatened habitats in the world, with consequences for their associated biodiversity. However, there are no evidence-based benchmarks for the proportion of area of naturally disturbed forests to be excluded from salvage logging to conserve biodiversity. We apply a mixed rarefaction/extrapolation approach to a global multi-taxa dataset from disturbed forests, including birds, plants, insects and fungi, to close this gap. We find that 75 ± 7% (mean ± SD) of a naturally disturbed area of a forest needs to be left unlogged to maintain 90% richness of its unique species, whereas retaining 50% of a naturally disturbed forest unlogged maintains 73 ± 12% of its unique species richness. These values do not change with the time elapsed since disturbance but vary considerably among taxonomic groups.

• MeSH
• benchmarking MeSH
• biodiverzita MeSH
• druhová specificita MeSH
• ekosystém MeSH
• lesnictví normy   MeSH
• lesy * MeSH
• zachování přírodních zdrojů * metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Hantaviruses are RNA viruses of the Bunyaviridae family, represented in the Czech Republic by three genospecies: Dobrava-Belgrade, Puumala and Tula. They persist in natural foci of infection. In 2004 to 2009, a local outbreak with 18 reported cases of nephropathia epidemica caused by Puumala hantavirus occurred in the Šumava mountains and foothills and was spacially associated with another outbreak in Lower Bavaria, Germany. In the Jelení locality in the Šumava mountains at 880 m above sea level, we identified a natural focus of infection suspected to be the source of hantavirus infection in forest workers. The focus was characterized geobotanically as a montane mixed forest with the predominance of beeches within the association Dentario enneaphylli-Fagetum, alliance Fagion, sub-alliance Eu-Fagenion, in a cold climate region with a podzolic soil. The biocenoses where hantaviruses are circulating typically show higher microclimate humidity. Their characteristization can be helpful in predicting where hantaviruses are likely to circulate.

• Klíčová slova
• Puumala, biocenosis, Myodes glareolus,
• MeSH
• Arvicolinae MeSH
• ekosystém MeSH
• epidemický výskyt choroby MeSH
• financování organizované MeSH
• Hantavirus MeSH
• hemoragická horečka s renálním syndromem epidemiologie   veterinární   MeSH
• lidé MeSH
• nemoci hlodavců epidemiologie   virologie   MeSH
• prevalence MeSH
• surveillance populace MeSH
• virus Puumala izolace a purifikace   MeSH
• zdroje nemoci veterinární   virologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Geografické názvy
• Česká republika MeSH

BACKGROUND AND AIMS: Ultraviolet-B radiation (UV-B) radiation damages the DNA, cells and photosynthetic apparatus of plants. Plants commonly prevent this damage by synthetizing UV-B-protective compounds. Recent laboratory experiments in Arabidopsis and cucumber have indicated that plants can also respond to UV-B stress with endopolyploidy. Here we test the generality of this response in natural plant populations, considering their monocentric or holocentric chromosomal structure. METHODS: We measured the endopolyploidy index (flow cytometry) and the concentration of UV-B-protective compounds in leaves of 12 herbaceous species (1007 individuals) from forest interiors and neighbouring clearings where they were exposed to increased UV-B radiation (103 forest + clearing populations). We then analysed the data using phylogenetic mixed models. KEY RESULTS: The concentration of UV-B protectives increased with UV-B doses estimated from hemispheric photographs of the sky above sample collection sites, but the increase was more rapid in species with monocentric chromosomes. Endopolyploidy index increased with UV-B doses and with concentrations of UV-B-absorbing compounds only in species with monocentric chromosomes, while holocentric species responded negligibly. CONCLUSIONS: Endopolyploidy seems to be a common response to increased UV-B in monocentric plants. Low sensitivity to UV-B in holocentric species might relate to their success in high-UV-stressed habitats and corroborates the hypothesized role of holocentric chromosomes in plant terrestrialization.

• MeSH
• Arabidopsis * MeSH
• chromozomy * MeSH
• fylogeneze MeSH
• lidé MeSH
• listy rostlin MeSH
• ultrafialové záření MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Chitwan National Park is surrounded by large settlements of people who exploit the areas where tigers and their prey occur. In this study, we measured the associations between the abundance of the prey of tiger with habitat, topographic, predator and human disturbance variables, using canonical correspondence analysis. We show that the abundance of hog deer is closely associated with areas of tall grassland and floodplains, while that of other ungulate species is associated with that of forests and short grasslands. Primates were mainly abundant in riverine and mixed forests. Abundances of most species, except hog deer and wild pig, were more closely associated with areas of forests than with open areas, because the latter were mainly occupied by humans and livestock. The presence of the species studied was closely associated with habitat and disturbance variables. Proximity of water holes was more closely associated with the presence of ungulates than primates. There were close associations between human disturbance and abundances of primates and muntjac, possibly because these species are more tolerant and adapted to human disturbance. However, the major prey species of tiger were negatively associated with human disturbance. As a consequence, human disturbance has resulted in a decline in the abundance of tigers and the lack of prey could result in their extinction in the Chitwan NP. Therefore, in terms of the conservation and management of the park, minimizing human disturbance of wildlife habitats and restoration of a buffer zone forest should be the prime objectives.

• MeSH
• ekosystém * MeSH
• lidé MeSH
• potravní řetězec MeSH
• stromy MeSH
• tygři * MeSH
• vysoká zvěř MeSH
• zachování přírodních zdrojů * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Scots pine (Pinus sylvestris L.) is a widespread tolerant forest tree-species; however, its adaptability to environmental change differs among sites with various buffering capacity. In this study, we compared the spatial effects of aridity index (AI) and nitrogen deposition (ND) on biomass density in natural and man-made pine stands of differing soil fertility using geographically weighted multiple lag regression. Soil fertility was defined using soil series as zonal trophic (27.9%), acidic (48.2%), gleyed (15.2%) and as azonal exposed (2.5%), maple (2.4%), ash (0.8%), wet (2.1%) and peat (0.9%) under pine stands in the Czech Republic (Central Europe; 4290.5 km2; 130-1298 m a.s.l.). Annual AI and ND in every pine stand were estimated by intersection between raster and vector from 1 × 1 km grid for years 2000, 2003, 2007 and 2010 of severe non-specific forest damage spread. Biomass density was obtained from a MODIS 250 × 250 m raster using the enhanced vegetation index (EVI) for years 2000-2015, with a decrease in EVI indicating non-specific damage. Environmental change was assessed by comparing predictor values at EVI time t and t+λ. Non-specific damage was registered over 51.9% of total forest area. Less than 8.8% of damaged stands were natural and the rest (91.2%) of damaged stands were man-made. Pure pine stands were more damaged than mixed. The ND effect prevailed up to 2007, while AI dominated later. Temporal increasing ND effect under AI effectiveness led to the most significant pine stand damage in 2008 and 2014. Predictors from 2000 to 2007 afflicted 58.5% of non-specifically damaged stands at R2 0.09-0.76 (median 0.38), but from 2000 to 2010 afflicted 57.1% of the stands at R2 0.16-0.75 (median 0.40). The most damaged stands occurred on acidic sites. Mixed forest and sustainable management on natural sites seem as effective remediation reducing damage by ND.

• MeSH
• borovice lesní * MeSH
• borovice * MeSH
• dusík MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Evropa MeSH

• Konspekt
• Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce
• NLK Obory
• humanitní vědy a umění
• antropologie

BACKGROUND AND AIMS: The increasing frequency of disturbances in temperate forests is responsible for the greater numbers of trees with mechanically damaged cambial zones. Adjustment of wood anatomical structure to balance between safe and efficient water conductivity is one mechanism trees employ to cope with mechanical damage. The relative role of disturbances, tree age and climate in shaping xylem conduits and affecting xylem hydraulic conductivity remains unknown. METHODS: We performed an experiment with five different mechanical treatments simulating natural disturbances of juvenile Betula pendula trees (stem scarring, tilting, decapitation, root exposure and stem-base burial). After 3 years, trees were cut down, conduit size and density were measured, and specific hydraulic conductivity of each tree ring was calculated. Between-tree and between-year variability in xylem conductivity was decomposed into effects of tree age, climate and disturbances using linear mixed-effects models. KEY RESULTS: Xylem-specific hydraulic conductivity decreased significantly after treatment in decapitated, tilted and scarred trees. In the last treatment, wood anatomical adjustment was restricted to the area next to the callus tissue zone; in contrast, specific hydraulic conductivity declined over the entire stem circumference after tilting or decapitation. The response of trees with buried stems and exposed roots was generally weak. The overall effect of disturbances on inter-annual variability of wood anatomical structure was greater than the contribution of tree age and climate. CONCLUSIONS: The results indicate that disturbances are important drivers of xylem hydraulic conductivity. Expected increases in the frequency and intensity of disturbances may alter the theoretical capacity of forest stands for water conductance with a feedback to climate.

• MeSH
• bříza * MeSH
• dřevo MeSH
• podnebí MeSH
• stromy * MeSH
• voda MeSH
• xylém MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Host abundance and landscape structure often interact to shape spatial patterns of many wildlife diseases. Emergence, spread, and persistence of African swine fever (ASF) among wild boar in eastern Europe has raised questions on the factors underlying ASF dynamics in this novel host-pathogen system. This work identifies drivers of ASF occurrence in natural wild boar population. We evaluated factors shaping the probability of ASF-postitive wild boar during the first three years (2014-2016) of the ASF epidemic in Poland. We expected to observe positive effects of wild boar density, proportion of forested area, human activity, and proximity to previous infections on ASF case probability. We tested these predictions using the infection status of 830 wild boar samples and generalized mixed-effects models. The probability of ASF case increased from 3 to 20% as population density rose from 0.4 to 2 ind./km2. The positive effect of population density on ASF case probability was stronger at locations near previous ASF incidents. ASF was more likely to occur in forested areas, with the probability of detecting an ASF positive sample rising from 2 to 11% as forest cover around the sample increased from 0.5 to 100%. This pattern was consistent at both low and high wild boar densities. Indicators of human activity were poor predictors of ASF occurrence. Disease control efforts, such as culling and carcass search, should be focused on high-density populations where chances of detecting and eliminating ASF-positive wild boar are higher. The intensity of control measures should decrease with distance from the infected area to match the observed spatial pattern of ASF case probability. Woodlands represent areas of the highest risk of ASF case occurrence. Distribution and connectivity of suitable habitats over the landscape can be used to prioritize disease-management actions.

• MeSH
• africký mor prasat epidemiologie   MeSH
• biologické modely MeSH
• divoká zvířata MeSH
• epidemie veterinární   MeSH
• interakce hostitele a patogenu * MeSH
• prasata MeSH
• pravděpodobnost MeSH
• prostorová analýza MeSH
• Sus scrofa MeSH
• virus afrického moru prasat fyziologie   MeSH
• životní prostředí MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Polsko MeSH

Here, for the first time, we report the thallium (Tl) isotope record in moderately contaminated soils with contrasting land management (forest and meadow soils), which have been affected by emissions from coal-fired power plants. Our findings clearly demonstrate that Tl of anthropogenic (high-temperature) origin with light isotope composition was deposited onto the studied soils, where heavier Tl (ε(205)Tl ∼ -1) naturally occurs. The results show a positive linear relationship (R(2) = 0.71) between 1/Tl and the isotope record, as determined for all the soils and bedrocks, also indicative of binary Tl mixing between two dominant reservoirs. We also identified significant Tl isotope variations within the products from coal combustion and thermo-desorption experiments with local Tl-rich coal pyrite. Bottom ash exhibited the heaviest Tl isotope composition (ε(205)Tl ∼ 0), followed by fly ash (ε(205)Tl between -2.5 and -2.8) and volatile Tl fractions (ε(205)Tl between -6.2 and -10.3), suggesting partial Tl isotope fractionations. Despite the evident role of soil processes in the isotope redistributions, we demonstrate that Tl contamination can be traced in soils and propose that the isotope data represent a possible tool to aid our understanding of postdepositional Tl dynamics in surface environments for the future.

• MeSH
• elektrárny MeSH
• látky znečišťující půdu MeSH
• monitorování životního prostředí MeSH
• půda * MeSH
• thallium * MeSH
• uhlí MeSH
• Publikační typ
• časopisecké články MeSH