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Title: Dynamic load during reactive strength tasks Objectives: Objectives were to explore and measure biomechanic parameters of athletes performing different reactive strength tasks using force plates. Methods: 8 male athletes (22,4 ± 1,2 years; 76,3 ± 4,3 kg) took part in experiment. Each of them performed 8 different reactive strength tasks (alternate and single leg bounds, pogo jumps on place, low hurdle jumps, high hurdle jumps 76 cm and 91 cm and long jump take off from 8 and 12 steps approach). Dynamics of tasks was measured using Kistler 9281 EA with sample rate of 1000 Hz. Main observed parameters were maximum vertical force, time to peak force, contact time and impulse. Data were processed in MATLAB R2022a (The MathWorks, Inc. Natick, Massachusetts, USA) and Microsoft Excel 2019. Results: Differences in dynamics of reactive tasks were observed among single leg and double leg exercises. Double leg exercises had much longer time to peak of vertical force than single leg exercises. Biggest vertical forces were observed during single leg bounds, where overload reached seven times body weight. On the other hand lowest peak of vertical force was measured during long jump takeoff from eight steps approach. Maximal forces got higher and contact time shorter with increased approach speed during...

In the mountains Hrubý Jeseník was the 18 monitoring plots in the years 2010-2013 conducted tramping of small mammals, inventory damage gnaw the bark of the beech forest plantations and the measured data to investigate the factors influencing the impact of small mammals. Small mammals were then evaluated in terms of dominance, impact on planting and statistically analyzed factors affecting impact. The results show that the dominant group were representatives Arvicolinae (n= 512, 62.4%): Clethrionomys glareolus (n= 306, 37.3%), Microtus agrestis (n= 181, 22.1%), Microtus arvalis (n=23, 2.8%), Microtus subterraneus (n= 2, 0.2%). In terms gnaw the bark of trees to damage most often involved in Microtus agrestis and Microtus arvalis, causing minor damage also Clethrionomys glareolus. Altitude, exposition, composition and character of the herb layer and abundance of voles are significant factors which can affect the impact of small mammals. This information can be useful for forest management, which can reduce the risk of the forest damage occurrence and decrease costs of silvicultural operations.

In Febuary 2013, in spectacular light and sound accompaintmen a meteorite hit the Russian Federation. Small fragment which landed in populated areas caused together with blust wave damage. The largest part broke the ice crust on the lake in outskirts of Chebarkul. The circular shaped hole gave rise to various conspiracy theories. About half of the year after impact the meteorite was lifted and conspiracy theories boken. The event immediately raised interest in the issue of the impacts of meteorites and phenomena associated with them. Processes when the meteor is passing trough atmosphere, impact craters, their origin and characteristics, computer models, types of meteorites and their origin. Or just a mystery of the hole in the ice crust of the lake Chebarkul. Science has got answers for such toppics. This paper is just trying to summarize them.

The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.

The DAISIE project in the 6. framework program of the European Union provides valuable data about European invasive species. Invasive plants have various impacts, positive and negative, and effects all four types of ecosystem services (supporting, provisioning, regulating and cultural). Invasive species are also known to cause serious economic looses. The proposed work aims at summarizing the up-to-date knowledge about the impact of invasive flora on European environment and human well-being. key words: invasive plants, impact, DAISIE, Europe, ecosystem services