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Soil micromycetes - the potential source of N.sub.2./sub.O in soils
Jirout, Jiří ; Šimek, Miloslav ; Elhottová, Dana
The aim of this paper is to summarize knowledge on potential production of N.sub.2./sub.O by fungi. The processes involved in the global nitrogen cycle are suggested to have an important role in the global environmental changes. Nitrification and denitrification processes cotribute to the production of N.sub.2./sub.O, which belongs to the group of highly active greenhouse gases. Denitrification - the successive reduction of nitrate to N.sub.2./sub. - was supposed to occur only in prokaryotes, but recently the evidence for dissimilation of nitrates and formation of nitrogen oxides and N.sub.2./sub. was reported also in fungi. N.sub.2./sub.O of fungal origin is formed from nitrate or nitrite by reduction under anaerobic or microaerobic conditions. Since fungi showed the capability to use denitrification and oxygen respiration simultaneously under various pO.sub.2./sub. conditions, the N.sub.2./sub.O production by fungi is expected in a wide range of soils with different aeration status.
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Culture Collection of Soil Actinomycetes in the Institute of Soil Biology BC ASCR, v.v.i. České Budějovice
Krištůfek, Václav ; Chroňáková, Alica ; Elhottová, Dana ; Petrásek, Jiří ; Němec, Jan
The Culture Collection of Actinomycetes in České Budějovice (CCACB) was established in 2006 that serves as a depository for cultures of soil actinomycetes. The cultures can be used for research, industrial applications, education and general scientific interest. Cultures are preserved mainly in glycerol or freeze-dried conserves. CCACB will offer strains of actinomycetes, namely streptomycetes (more than 900 cultures at the present moment), in catalogue of cultures www.upb.cas.cz, www.actinomycetes.cz.
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Detection of microorganisms in the soil using CARD-FISH (Catalyzed Reporter Deposition - Fluorescence in situ hybridization)
Krištůfek, Václav ; Kasalický, Vojtěch ; Chroňáková, Alica ; Elhottová, Dana ; Němec, Jan
CARD-FISH protocol (Catalyzed Reporter Deposition - Fluorescence in situ Hybridization) for detection of soil microbial community composition was successfully established in the Institute of Soil Biology. CARD-FISH is the relatively new molecular biology tool permitting to quantify distinct groups of microorganisms by hybridization of specific oligonucleotide probes. Compared to classic FISH-protocol the probe-attached enzyme amplifies the fluorescent signal and enables to detect nearly all microorganisms in soil or in organic compounds. As the first, we used this method to determine the bacterial community composition of a dated layer of guano-heap from Domica Cave (Slovak Carst National Park, Slovakia). We quantified the percentuel composition of Archaea, Eubacteria (.i.Planktomycetales, Verrucomicrobiales./i. included) and major bacterial groups (Actinobacteria, proteobacteria, .i.Cytophaga-Flavobacter./i.-Bacteroidetes, Sphingobacteria).
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Changes of microbial communities resulting from the passage through the earthworm gut
Němcová, Anna ; Pižl, Václav ; Elhottová, Dana
Selective effect of earthworm gut conditions is participating in the reduction or stimulation of individual microbial groups. In general, the passage through the earthworm digestive tract leads to an increase of total active microbial biomass. The numbers of cultivable bacteria present in earthworm gut are not shifted significantly in comparison with surrounding environment but their species richness changes. Usually some bacterial groups are partially changed during the passage. The long-lasting effect of the passage and animal excretion into the soil can involve the function of important microbial groups. The aim of this study was to summarize current knowledge about both quantitative and qualitative characteristics of the microflora connected with these significant representatives of soil macrofauna.
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The cultivation of bacteria originated in bat guano
Petrásek, Jiří ; Elhottová, Dana ; Krištůfek, Václav ; Kováč, L.
The bat guano represents an important source of organic matter in the oligotrophic caves. The high content of chitin from the remains of digested insect in bat diet causes the slow decomposition of the guano. The bat guano deposits can be auccumulated near the bat colonies during hundreds of years. The bat guano represents unique environment with specific conditions and appropriate composition of bacterial community. In this study, the bacterial communities of the guano from Domica and Ardovská Caves (NP Slovak Karst) were investigated using plate method with six different growing media. Total numbers of cultivable aerobic bacteria in guano were determined on the solid complex medium TSBA (Becton & Dickinson]. Total numbers of cultivable anaerobic bacteria were determined on the DifcoTM Anaerobic agar and blood agar (Schaedler agar with 5% sheep blood).
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GPC of soil humic and fulvic acids from Trojmezí area
Šestauberová, Martina ; Novák, František
Humic (HA) and fulvic acids (FA) were isolated from individual soil horizons from podzol of spruce forest in Trojmezí stand (Bohemian Forest, 48°46´25¨ N, 13°51´04¨ E). Their molecular weight M.sub.r./sub. and weight-average molecular weight M.sub.w./sub. were determined by the gel permeation chromatography(GPC). For the high-molecular HA fraction (HM-HA), it was found the range of M.sub.r./sub. 380 – 569 kDa, for the main fraction of HA and for FA 6.7 – 31.4 kDa and 1.8 – 3.3 kDa, respectively. The M.sub.r./sub. of humic substances and the proportion of HM–HA decreased with soil depth. HA isolated from horizon B.sub.h./sub. didn´t contain any high-molecular fraction and its molecular weight approached the values specified for FA.
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The impact of ungulates on epigeic assemblages of centipedes (Chilopoda) in the Křivoklátsko Protected Landscape Area - preliminary results
Aurová, Klára
The Křivoklátsko Protected Landscape Area and Biosphere Reserve (Czech Republic) represents a unique region covered in a high portion by forest ecosystems. Densities of ungulates in the forests are unusually high. Their impact on ecosystem is important, especially due to the removal and consumption of herbage, trampling of soil and vegetation, and the return of excreta. The aim of field study was to elucidate the impact of ungulates on soil invertebrates represented by centipedes. In this paper the first data about possible impact of ungulates on epigeic assemblage of centipedes are presented. In total, 9 centipede species were recorded. The species .i.Lithobius mutabilis./i. was dominant during the whole observation in all monitored plots. At the beginning of the experiment in 1994, this centipede outweighed other species with 91 %. After 12 years in 2006 the amount of other species arose almost up to 1/4 outside and more than 1/3 inside the fenced plots.
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Seasonal development and vertical distribution of soil rotifer populations in South-Bohemian beech forest
Devetter, Miloslav
The soil rotifer community in a climax beech forest in South Bohemia was investigated during 2005 focusing on seasonal and vertical distribution changes. Samples 10 cm.sup.2./sup. large and 10 cm in depth were divided into 5 layers, which were processed separately. Altogether 31 rotifer species were determined during the investigation, of these 9 species were monogononts, while the rest were bdelloids. The most important species were .i.Encentrum arvicola, Wierzejskiella vagneri./i. among the monogononts and .i.Adineta steineri, Ceratotrocha cornigera, Habrotrocha filum, H. ligula, Macrotrachela plicata, Mniobia tentans, M. incrassata, M. granulosa./i. among the bdelloids. Mean Shannon diversity index varied from 1.99 to 2.63. Total rotifer abundance varied from 212 (± 63) to 513 (± 127) 10.sup.3./sup. ind. m.sup.-2./sup. year-round, with the highest numbers found in May, while the lowest were in July.
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