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Vliv kultivačních podmínek na kryoprezervaci půdních řas a sinic
Lukešová, Alena
Fundamental principles of both conservative and vitrification cryopreservation methods are presented, and factors affecting cryopreservation of algae and cyanobacteria are summarized. These factors include factors connected with the cryopreservation process itself as well as factors connected with pre- and post-cryopreservation manipulation with samples. Attention is paid to cultivation conditions, mainly to the temperature in the context of application of cold acclimation before cryopreservation. Both literature data and our experience indicate that the response of soil algae and cyanobacteria to particular factors is species or strain specific and optimization of condition can enhance post-cryopreservation viability of cryopreservation recalcitrant strain.
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Může průchod střevem žížal ovlivnit strukturu jílových minerálů: předběžné výsledky
Hušák, M. ; Frouz, Jan ; Had, J.
The effect of gut passage by three earthworm species (.i.Lumbricus rubellus, Dendrobaena octaedra, Dendrodrilus rubidus./i.) on the structure of ingested clay minerals was studied using X ray powder diffractometery. No differences were found in the peak's positions in diffraction spectra of clay spoil and clay in earthworm casts, indicating no changes in clay lamella inter-spacing. Differences were found in the peak's sizes, which seem to be caused by changes in preferential orientation of clay minerals during gut passage.
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Povrchová aktivita osmi běžných druhů chvostoskoků ve smrkových lesích a na pasekách po kůrovcové kalamitě v Národním parku Šumava, Česká republika
Brůhová, Jindřiška ; Rusek, Josef
Surface activity of eight common epigeic species of Collembola were studied in spruce forests, dead spruce forests and clearings in the Šumava National Park, South Bohemia, Czech Republic: .i.Lepidocyrtus lignorum, Leidocyrus cyaneus, Pogonognathellus longicornis, Tomocerus minutus, Tetracanthella stachi, Allacma fusca, Entomobrya nivalis, Dicyrtomina minuta./i.. Five pitfall traps were exposed at each of the 9 sites in the summer and autumn periods to study the impact of spruce forest die-off after bark beetle attack (dead forests) and on clearings. Material comprising 79435 specimens was evaluated in this study using the non-parametric Kruskal-Wallis test for comparing Collembola activity between the sites and seasons. Complete linkage (Euclidean distances) cluster analysis was used for comparing the collembolan activity in all nine sites.
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Energetika larev tří druhů čeledi Bibionidae
Frouz, Jan ; Šustr, Vladimír ; Kalčík, Jiří
Food consumption, defecation, assimilation and production were studied in three species of bibionid larvae (.i.Bibio marci, B. pomonae, Penthetria holosericea./i.) feeding either on leaf litter or their own excrements. Assimilation efficiency of larvae feeding on leaf litter was in all species higher then assimilation efficiency of the same species feeding on their own excrements. Larvae reared on excrements also lost weight, which indicated that excrements were insufficient as an exclusive source of energy. In .i. B. marci, P. holosericea./i. the effect of temperature on assimilation efficiency was studied. In .i. P. holosericea./i. assimilation efficiency decreased with increasing temperature. This trend was not observed in .i. B. marci. B. marci./i. was fed on pure cellulose to test if cellulose can serve as the only source of energy. Mortality of larvae feeding on cellulose was significantly higher than of those feeding on leaf litter and did not differ from starving larvae.
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Sukcese hmyzenek (Protura) a vidličnatek (Diplura) na haldách chemické továrny
Rusek, Josef
Primary succession of Protura and Diplura was studied on deposits of a former chemical factory at Petrovice u Karviné, NE Moravia, Czech Republic, in 1978-1979, 1993 and in 2002-2004. Chemically loaded deposits were 15, 25 and 60 years old in 1979 and a primary succession without plant re-cultivation took place there. The succession was delayed on small humps and slopes where the deposited substrate was covered by terrestrial algae, lichens and mosses. Protura did not enter the primary succession before a moss cover occurred on the 15 years old heap and they were represented only by .i.Acerentulus traegardhi./i.. Three species of Protura were established in the 20 years old grass-covered stage as well as on the 49 years old heap. They occurred in low densities up to the 74 years old stage (and older), in which a proturan community of 4-6 species was established.
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Vliv různých travních směsí na společenstva pancířníků (Acari: Oribatida) v iniciálních sukcesních stádiích během obnovy květnatých luk
Starý, Josef
Altogether 400 quantitative soil samples were taken from 8 stationary plots in the localities Výzkum and Čertoryje in the Bílé Karpaty Mts. during the years 1999-2002. The present study is based on material of 10563 oribatid specimens belonging to 62 oribatid species. The lowest species richness and mean abundance were recorded on the plot with agricultural management.The highest mean abundance was found on the old sub-xerothermic meadow in Čertoryje. The eurytopic species .i.Scheloribates laevigatus./i. and .i.Tectocepheus velatus./i. as well as the heliophilous .i.Punctoribates punctum./i. were eudominant in all studied plots. These eudominant species were complemented by the dominant and recedent eurytopic species .i.Microppia minus, Hemileius initialis, Achipteria coleoptrata./i. and .i.Medioppia subpectimata./i.. The rare xerophilous species .i.Lucoppia burrowsi./i. was found in the plots sowed by different grass mixtures and in the fallow.
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Mikroskopické houby v půdě, listovém opadu, exkrementech a střevním traktu .i.Dendrobaena mrazeki./i. (Lumbricidae)
Nováková, Alena ; Pižl, Václav
Species diversity and quantitative parameters (mycelial length, CFU counts) of saprotrophic microfungi assemblages were studied in the intestine and casts of .i.D. mrazeki./i. and compared with those in soil and litter at four plots of a thermophilous oak forest in Southern Moravia (Czech Republic) in 2004. Soil dilution plate method and soil washing technique and three isolation media were used for the isolation of fungi. Differences in species number and composition of fungi assemblages were found both among individual substrates studied and between the results of different isolation methods. Number of species isolated by the soil dilution plate method was higher in earthworm casts than in soil, however, the opposite results were obtained using soil washing technique. CFU counts reached the highest values in leaf litter.
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Emissions of greenhouse gases (N2O and CO2) from pasture soil as a result of activity of soil microbial community - preliminary results
Šimek, Miloslav ; Hynšt, Jaroslav ; Brůček, Petr ; Čuhel, Jiří
Cattle overwintering area was shown an important point source of N2O and CO2. The emissions of N2O were mostly directly related to the rate of animal impact as the greatest fluxes of N2O and the highest total cumulative N2O emissions as well were found at the most impacted site. The fluxes of N2O were however very variable in time and most of N2O was emitted during several short events in spring or in winter. Laboratory experiments suggested that total amount of nitrogen escaping from soil from impacted sites is much greater than indicated by field measurements of N2O fluxes and molecular nitrogen (N2) was shown as the main nitrogen gas. It is hypothesized that soil pH is a crucial soil factor controlling the mole fraction of N2O: under slightly alkaline conditions in severely impacted soils, denitrification is completed and most of nitrogen escapes from the soil as N2; under more acidic conditions, however, the activity of nitrous oxide reductase is partly reduced.
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Dynamics of N2O emissions after C and N amendments of soil at the cattle overwintering area
Hynšt, Jaroslav ; Brůček, Petr ; Čuhel, Jiří ; Šimek, Miloslav
Field experiments were carried out at the cattle overwintering area in South Bohemia, Czech Republic, focused on the emissions of N2O after soil amendments with nitrate and glucose. Emissions were estimated using a permanent static chamber technique. Nitrate and glucose amendments caused very sharp increases of N2O fluxes, which however diminished after 2-3 days. Total amount of N2O escaping the soil was related to the amount of N and C added, and was calculated to 1-15 kg N.ha-1 (0.2-3% of N applied). Emissions were heterogeneous, which is shown by great differences among the individual chambers. Emissions were variable in time and very probably were controlled by temperature, as they approximately followed the air and surface soil temperature patterns. Despite the timing of amendment application, peaks of emissions were always determined 6 hours after the amendments.
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