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České Budějovice, Czech Republic

Bujalsky L.,Charles University | Kaneda S.,Japan National Institute for Agro - Environmental Sciences | Dvorscik P.,Charles University | Frouz J.,Charles University | Frouz J.,Institute of Soil Biology
Ecological Engineering

Soil respiration accounts for much of the CO2 released from terrestrial ecosystems into the atmosphere. Although respiration depends on temperature, the relationship between respiration and temperature may vary among soils. Here, we measured soil respiration and soil temperature in chronosequences of reclaimed and unreclaimed post-mining sites (10-50-year-old coal mining heaps near Sokolov, the Czech Republic) to determine the major factors affecting temperature-dependent soil respiration. Soil respiration was repeatedly measured in situ during 2011 and 2012 at five reclaimed sites (planted with alder) and five unreclaimed sites (overgrown with willow, birch, and aspen). In addition, spatial heterogeneity was assessed by repeatedly measuring soil respiration at 30 permanent points at one 28-year-old site (the "30-point" site) in 2007-2008. In all sites root biomass, soil carbon (C) content, soil pH, and the thickness of Oe layer were also measured. In the chronosequences and 30-point site, the relationship between soil respiration and temperature increased with soil C content; soil respiration was unrelated to temperature if soil C content was <9%. The increase in respiration with temperature was enhanced by a thick Oe layer and by high root biomass.Soil respiration at reclaimed sites increased with site age to age 30 years and then decreased. The decrease in respiration at the older sites was associated with a decrease in soil temperature (associated with increased shading). Respiration at unreclaimed sites increased with age and was usually lower than in reclaimed alder plantation of similar ages. © 2014 Published by Elsevier B.V. Source

Kontschan J.,Hungarian Academy of Sciences | Stary J.,Institute of Soil Biology
Acta Zoologica Academiae Scientiarum Hungaricae

Seven Uropodina species were listed from Malaysian soil samples deposited in the Institute of Soil Biology of the Three of them are already known species (Deraiophorus mirabilis KONTSCHÁN, 2010, Depressorotunda (Depressorotunda) malaya KONTSCHÁN, 2010, Uroobovella serangensis HIRAMATSU, 1980). Four species (Cyllibula ovalis sp. n.; Uropoda gigantea sp. n.; Phymatodiscus malayicus sp. n. and Depressorotunda (Depressorotunda) batuensis sp. n.) are new to science. Original drawings and description of new species are given. An additional key to the species of the subgenus Depressorotunda (Depressorotunda) is presented. Source

Anders E.,AIT Austrian Institute of Technology | Anders E.,University of Natural Resources and Life Sciences, Vienna | Watzinger A.,AIT Austrian Institute of Technology | Rempt F.,AIT Austrian Institute of Technology | And 7 more authors.
Agricultural and Food Science

Biochar application is a promising strategy for sequestering carbon in agricultural soils and for improving degraded soils. Nonetheless, contradictory and unsettled issues remain. This study investigates whether biochar influences the soil microbial biomass and community structure using phospholipid fatty acid (PLFA) analysis. We monitored the effects of four different types of biochar on the soil microbial communities in three temperate soils of Austria over several months. A greenhouse experiment and two field experiments were conducted. The biochar application did not significantly increase or decrease the microbial biomass. Only the addition of vineyard pruning biochar pyrolysed at 400°C caused microbial biomass to increase in the greenhouse experiment. The biochar treatments however caused shifts in microbial communities (visualized by principal component analysis). We concluded that the shifts in the microbial community structure are an indirect rather than a direct effect and depend on soil conditions and nutrient status. Source

Watzinger A.,AIT Austrian Institute of Technology | Feichtmair S.,AIT Austrian Institute of Technology | Feichtmair S.,University of Natural Resources and Life Sciences, Vienna | Kitzler B.,Institute of Soil Biology | And 6 more authors.
European Journal of Soil Science

This study investigates (i) the effect of biochar amendments on soil microbial communities in temperate agricultural soils, (ii) the involvement of microorganisms (MOs) in degradation of biochar and (iii) techniques to quantify degradation of biochar in short-term experiments. The study involved an incubation experiment and a pot experiment with two arable soils (a sandy acidic Planosol and a calcareous loamy Chernozem) amended with 13C-depleted biochar from wheat husk and willow plants. Phospholipid fatty acids (PLFAs), 13C-PLFA, CO2, 13C-CO2, soil organic carbon (Corg) and 13C-Corg were monitored for 100days. Effects of biochar application on the soil microorganisms (MOs) were generally minor. In the incubation experiment, microbial biomass was elevated by wheat husk biochar, especially in the Planosol. The increase in PLFAs was attributed to Gram-negative bacteria and actinomycetes. Fungi and Gram-positive bacteria were less affected. In the pot experiment, MOs did not respond to the addition of willow biochar. The effects of biochar were mainly attributed to an increase in the pH of the Planosol. Additionally, MOs were probably less responsive to inorganic fertilizer in biochar-amended soil. In the incubation, only the actinomycetal PLFA 10Me18:0 incorporated biochar C, while in the pot experiment, Gram-negative bacterial PLFAs (16:1ω7c, 16:1ω5c, 18:1ω7c) and Me16:0 & i17:1ω8 and i17:0 indicated degradation of biochar after 5weeks. Uptake of around 20% biochar C in these PLFAs was monitored, which accounts for 2% biochar C in the total microbial biomass. From the PLFA data the mean residence time of biochar carbon was estimated in time-scales of centuries to millennia. The CO2 concentration decreased after biochar addition until its production was masked by root respiration. The use of 13C-CO2 labelling to estimate degradation was complicated by the interference with an initial negative priming effect and the dissolution/precipitation of carbonate. In conclusion, soil MOs were not particularly affected by addition of biochar, and the effects recorded were mainly attributed to changing environmental conditions after biochar addition. Nonetheless, uptake of 13C label into microbial PLFAs was successfully used to estimate microbial degradation of biochar in short-term experiments. © 2013 British Society of Soil Science. Source

Hedenec P.,Institute of Soil Biology | Hedenec P.,Charles University | Novotny D.,Czech Republic Crop Research Institute | Ustak S.,Czech Republic Crop Research Institute | And 7 more authors.
Biomass and Bioenergy

Biofuel crops are an accepted alternative to fossil fuels, but little is known about the ecological impact of their production. The aim of this contribution is to study the effect of native ( Salix viminalis and Phalaris arundinacea) and introduced ( Helianthus tuberosus, Reynoutria sachalinensis and Silphium perfoliatum) biofuel crop plantations on the soil biota in comparison with cultural meadow vegetation used as control. The study was performed as part of a split plot field experiment of the Crop Research Institute in the city of Chomutov (Czech Republic). The composition of the soil meso- and macrofauna community, composition of the cultivable fraction of the soil fungal community, cellulose decomposition (using litter bags), microbial biomass, basal soil respiration and PLFA composition (incl. F/. B ratio) were studied in each site. The C:N ratio and content of polyphenols differed among plant species, but these results could not be considered significant between introduced and native plant species. Abundance of the soil meso- and macrofauna was higher in field sites planted with S. viminalis and P. arundinacea than those planted with S. perfoliatum, H. tuberosus and R. sachalinensis. RDA and Monte Carlo Permutation Test showed that the composition of the faunal community differed significantly between various native and introduced plants. Significantly different basal soil respiration was found in sites planted with various energy crops; however, this difference was not significant between native and introduced species. Microbial biomass carbon and cellulose decomposition did not exhibit any statistical differences among the biofuel crops. The largest statistically significant difference we found was in the content of actinobacterial and bacterial (bacteria, G+ bacteria and G- bacteria) PLFA in sites overgrown by P. arundinacea compared to introduced as well as native biofuel crops. In conclusion, certain parameters significantly differ between various native and introduced species of biofuel crops; however, the functional importance of these differences requires further research. © 2013 Elsevier Ltd. Source

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