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In water quality research the interest in online biofilm monitoring techniques has recently increased significantly. Christiani et al. (2008) presented a simple electrochemical technique to monitor electro-active biofilm in soil, based on the cathodic polarisation of stainless steel electrodes. Authors present an improved method, in which stainless steel was replaced by copper. By using copper-zinc electrodes authors have shown difference in the electrical potential between sterilized and native soils even at low moisture content.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Yao, F. Wang, L. Tian, Y. Zhou, H. Chen, K. Chen, N. Gai, R. Zhuang, T. Maskow, B. Ceccanti, and G. Zaray

Abstract  

Using TAM III multi-channel calorimetry combined with direct microorganism counting (bacteria, actinomycetes and fungi) under laboratory conditions, we determined the microbial population count, resistance and activity toward cadmium (Cd(II)) and hexavalent chromium (Cr(VI)) toxicity in soil. The thermokinetic parameters, which can represent soil microbial activity, were calculated from power-time curves of soil microbial activity obtained by microcalorimetric measurement. Simultaneous application of the two methods showed that growth rate constant (k), peak-heat output power (P max) and the number of living microorganisms decreased with increasing concentration of Cd and Cr. The accumulation of Cr on E. coli was conducted by HPLC-ICP-MS. Cr6+ accumulation by Escherichia coli was increased steadily with increasing Cr6+ concentration. The results revealed that the change in some thermo-kinetic parameters could have good corresponding relationship with metal accumulation. Our work also suggests that microcalorimetry is a fast, simple, more sensitive, on-line and in vitro method that can be easily performed to study the toxicity of different species of heavy metals on microorganism compared to other biological methods, and can combine with other analytic methods to study the interaction mechanism between environmental toxicants and microbes.

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Soil biological properties and CO 2 emission were compared in undisturbed grass and regularly disked rows of a peach plantation. Higher nutrient content and biological activity were found in the undisturbed, grass-covered rows. Significantly higher CO 2 fluxes were measured in this treatment at almost all the measurement times, in all the soil water content ranges, except the one in which the volumetric soil water content was higher than 45%. The obtained results indicated that in addition to the favourable effect of soil tillage on soil aeration, regular soil disturbance reduces soil microbial activity and soil CO 2 emission.

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Journal of Thermal Analysis and Calorimetry
Authors: Lisardo Núñez-Regueira, J. Proupín-Castiñeiras, J. Rodríguez-Añón, Maria Villanueva-López, and O. Núñez-Fernández

Abstract  

The design of a rigorous experimental procedure is the basis for any environmental study. In this work, the basic criteria are established for determination of soil health using microcalorimetry as the main technique complemented by the study of physical (temperature, moisture, porosity, hydraulic conductivity, density and plasticity), chemical (pH and C to N ratio) and biological features (most probable number of microorganisms and organic matter content), and also environmental properties in the form of bioclimatic diagrams. The design was elaborated using as a reference a humic eutrophic-Cambisol subjected to afforestation with P. pinaster Aiton situated in Viveiro (Galicia, NW Spain). Main results of this study refer to total heat evolved during the processes (2.65 to 3.81 J g–1), time to reach the maximum of the peak from 16.17 to 19.29 h, and microbial growth rate constant from 0.0732 to 0.1043 h–1. These results change over the year as they are influenced by the action of environmental parameters over soil microbial activity. The results are in close agreement with some others previously reported using different experimental techniques.

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The aim of the study was to investigate the relationships between the vascular plant species and the associated soil microbial properties at various stages of vegetation development on unclaimed hard coal mine spoil heaps in Upper Silesia (south Poland). The spontaneous vegetation, soil chemistry as well as the activity and structure of microbial communities were recorded on this specific habitat. The colliery heaps were divided into four age classes and the plant species composition and cover abundance were recorded on established plots (2 m × 2 m). The soil microbial activity under the vegetation patches was assessed using fluorescein diacetate hydrolytic activity (FDHA) and the soil microbial biomass and community composition were determined by phospholipid fatty acid (PLFA) biomarkers. Total microbial biomass in soils from the older vegetation plots was significantly higher than those in soils from the younger plots. In all studied samples, microbial communities consisted primarily of bacteria with the dominance of Gram negative bacteria over Gram positive and aerobic microorganisms were more dominant than anaerobic ones. Statistical analysis revealed a correlation between the type of vegetation and microbial community structure.

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Journal of Thermal Analysis and Calorimetry
Authors: Lisardo Núñez-Regueira, J. Rodríguez-Añón, J. Proupín-Castiñeiras, Maria Villanueva-López, and O. Núñez-Fernández

Abstract  

Microcalorimetry was used to study the seasonal evolution over one year of the microbial activity in a humic-eutrophic Cambisol soil as a function of its forest cover. The study was carried out on three soils with identical origin but covered with different forest species: pine, eucalyptus, and a typical Atlantic-humid riverside forest. Some other physical, chemical and biological properties and environmental parameters, mainly humidity and environmental temperature, were considered to analyze their influence on soil microbial activity. The study was performed using a microcalorimeter Thermal Analysis Monitor 2277 in which the experiments were carried out with 1 g soil samples treated with 1.25 mg glucose g–1 soil. From the measured results it follows that pine forest soil is the least productive of the three, as it generates an average heat of 2.7 vs. 5.9 J g–1 generated by the eucalyptus forest soil and 3.1 J g–1 generated by the riverside forest soil. These results are dependent on the remaining physical, chemical and biological features analysed and because of this, pine forest soil, with a pH value 3.3 in spring, shows a small capacity to maintain a stable microbial population which is the lowest of the three (0.079108 to 0.46108 microorganisms g–1 soil) while riverside soil microbial population is in the range from 7.9108 to 17108 microorganisms g–1 soil.

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A pot experiment was set up at the Experimental Farm of the Faculty of Horticultural Sciences of the Szent István University in 2001 investigating the revitalization effect of selected treatments on thermal-treated soils and other production substances. In the experiment 6 factors and 7 treatments were used, each in 4 replicates, using rape ( Brassica napus DC ) as test plant. During the time period of the experiment (29 May-17 August) continuous observations and measurements were conducted, plant and soil analyses - chemical and microbiological - were made to establish the main effects and results of the different treatments. These are discussed in the paper in detail. Although the soil-vitalization procedures were of great success, no treatment in the experiment had an extremely positive effect. Various additives, however could enhance the re-colonization processes significantly.  According to the basic factors (the soils or substrates) the best treatments were: the A1 (clay-pearl) additive and the C2, C3 factors (the medium and low temperature soil treatments).  Among the treatment combinations, treatments IV and VII were the best ( compost and compost + inocula addition). This fact shows that the compost in a good quality, and the compost enriched, compost extracted microbial inocula can play the most important role in the revitalization of thermal-treated soils. Manure addition and the manure + inocula treatment can also be used as a prominent treatment in the restoration, to increase the organic matter content and the microbial activity in soils. The single alga- and microbial inocula treatment was not successful permanently, therefore their use - without adding any parallel organic matter - cannot be recommended. Investigations of the soil microbial activity showed that the lowest temperature of thermal treatments had resulted a more effective revitalization. The clay-pearl additive increased the persistency and activity of the microbes in the soil. It was also obviously found that the organic additives with or without the microbial inoculations could be used potentially as the best soil revitalization treatments. 

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Acta Microbiologica et Immunologica Hungarica
Authors: Katalin Szakmár, Olivér Reichart, István Szatmári, Orsolya Erdősi, Zsuzsanna Szili, Noémi László, Péter Székely Körmöczy, and Péter Laczay

activity and N-transformation processes due to sulfadiazine loads in pig-manure. Environ Pollut 153 , 315–322 (2008). Schloter M Alterations in soil microbial activity and N

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wastewater for irrigation [ 10 – 13 ]. However, wastewaters often contain microbial and chemical constituents that may directly affect the natural soil microbial activity, as consequence, this procedure can cause troubles in growth of plants [ 14

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148 154 BEZDICEK, D. F., BEAVER, T. & GRANATSTEIN, D., 2003. Subsoil ridge tillage and lime effects on soil microbial activity, soil pH, erosion, and wheat and pea yield in the

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