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Abstract

The experiment consisted in monitoring the count of moulds and three selected Trichoderma sp. isolates (T1 - Trichoderma atroviride, T2 - Trichoderma harzianum, T3 - Trichoderma harzianum) in vegetable (onion and tomato) waste composted with additives (straw, pig manure). Additionally, the aim of the study was to determine the type of interaction occurring between autochthonous fungi isolated from composts after the end of the thermophilic phase and Trichoderma sp. strains applied in the experiment. Number of microorganisms was determined by the plate method, next the identification was confirmed. The rating scale developed by Mańka was used to determine the type of interactions occurring between microorganisms. The greatest count of moulds in onion waste composts was noted in the object which had simultaneously been inoculated with two strains T1 - T. atroviride and T3 - T. harzianum. The greatest count of moulds was noted in the tomato waste composts inoculated with T2 - T. harzianum strain. Microscope identification revealed that Penicillum sp., Rhizopus sp., Alternaria sp. and Mucor sp. strains were predominant in onion waste composts. In tomato waste composts Penicillium was the predominant genus, followed by Rhizopus. The test of antagonism revealed the inhibitory effect of Trichoderma isolates on most autochthonous strains of moulds. Tomato waste composts proved to be better substrates for the growth and development of Trichoderma sp. isolates. The results of the study show that vegetable waste can be used in agriculture as carriers of antagonistic microorganisms.
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Abstract

The paper presents microbiological characteristic of sewage sludge composted in controlled conditions together with biowastes (wheat, maize and rapeseed straw, sawdust and refined glycerol). An experiment was carried out in which the material was mixed at appropriate weight proportions and then placed in bioreactor chambers of constant air flow (4 lźmin-1). The performed composting process aimed at determining the developmental dynamics of heterotrophic bacteria, molds, actinomycetes as well as bacteria from Salmonella genus and Enterobacteriaceae family. Microbiological analyses were performed on selective substrates using Koch's plate method. Moreover, using the floatation method, the presence of live eggs of ATT (Ascaris spp., Trichuris spp., Toxocara spp.) intestinal parasites was assessed and levels of dehydrogenase activity were determined using 1% triphenylotetrazole chloride as a substrate. It was concluded, on the basis of the obtained research results, that the composting process reduced bacterial counts of heterotrophic bacteria, molds and the activity of dehydrogenases activity in all experimental treatments. On the other hand, no reduction was observed in quantities of actinomycetes in the composted materials whose changes in numbers were found to correlate positively most strongly with levels of dehydrogenases activity. In addition, it was found that changes in numbers of the analysed groups of microorganisms depended, primarily, on the pH value and concentrations of ammonia released from the composted materials. Furthermore, the obtained research results also revealed that the sewage sludge used in the experiment did not contain Salmonella spp. bacteria and live eggs of ATT intestinal parasites, and that the composting process reduced completely numbers of bacteria from the Enterobacteriaceae family in all compost treatments. The obtained composts fulfilled all sanitary standards complying with the requirements issued by the Minister of Agriculture and Rural Development (2008) as well as with the EU regulation (EC) No. 185/2007 from February 2007 changing EEC regulations No. 809/2003 and No. 810/2003 connected with the extension of the period of transitional requirements for composting and biogas plants as provided by the EU regulation No. 1774/2002 of the European Parliament and Council.
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Abstract

The effects of different volumetric ratios of bulking agents to pulp/paper-mill sludge on composting were studied. Rice husk and corncob were used as bulking agents. Volumetric ratios of bulking agents to pulp/paper-mill sludge were used as 10:100 and 25:100. To monitor the evolution of the composting systems, routine parameters such as temperature, moisture, pH, total N, NH4 +-N, NO3 --N, total C, and C/N ratio were analyzed. The results indicated that the agro-based materials significantly affected compost maturity parameters. Moreover, the quality of the product obtained in the composting process treated with the agro-based materials achieved satisfactory stabilization and sanitation for application to land.
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Abstract

The aim of the research was to assess the microbiological (number of heterotrophic bacteria, actinobacteria and moulds) and biochemical (urease and acid phosphatase activity) state of peat with the admixture of composts produced from sewage sludge. An additional aim of the research was to demonstrate the influence of those substrates on the morphological traits of scarlet sage (height, number and length of shoots, number of buds and inflorescences, greenness index (SPAD)). Composts produced from sewage sludge, wheat, maize and lupine straw were mixed with peat, where their percentage varied from 25% to 75%. The substrate which included the composts applied in the experiment had a higher number of heterotrophic bacteria and a higher acid phosphatase activity level than the control substrate (peat). The multiplication of moulds and actinobacteria was more intensive than in the peat only in the combinations with K3 (sewage sludge 50%+sawdust 20%+ lupine straw 30%) and K4 (sewage sludge 50%+sawdust 20%+fresh maize straw 30%) composts, whereas the highest urease activity level was observed in the soils produced from K1 (sewage sludge 50%+sawdust 20%+white straw 30%) compost. The most optimal development of plants was observed in the substrate with compost produced from wheat straw. Composts produced from municipal sewage sludge were found to be suitable for growing scarlet sage. However, their effect depends on the percentage of high peat in the substrate.
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Abstract

The paper addresses the effect of a compost prepared from tobacco wastes with an admixture of bark and straw on the enzymatic activity and certain chemical properties of a grey-brown podzolic soil amended with that compost. The study was conducted under the conditions of a pot experiment in which the soil material was collected from the surface horizon of the grey-brown podzolic soil. The effect of the application of the compost was compared with soil without such amendment. The test plant was maize cv. Kosmo 230. Fertilisation of the light soil with the compost studied caused changes in the enzymatic activity of the soil that were related both to the dose of the compost and to the kind of enzyme studied. With increase in the dose of the compost there was an increase in dehydrogenase activity (highest dose) and a significant decrease in the activity of acid phosphatase. Moreover, it was observed that tobacco compost was a significant source that enriched the light soil in organic matter, total nitrogen, and available forms of phosphorus, magnesium and potassium, which was evident in increased yields of maize grown as the test plant. Significant correlations were also demonstrated between a majority of the biochemical and chemical parameters, which indicates that those parameters characterise well the biological properties of a grey-brown podzolic soil amended with tobacco compost.
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Abstract

The compost derived from cellulosic material coming from the Public Utility Company in Zabrze (Poland) was investigated for its capability for adsorbing acid dyes from aqueous solution at various concentrations of the dyes and the compost dosages. Four acid dyes were investigated: Acid Red 18 (AR-18), Acid Blue 9 (AB-9), Acid Green 16 (AG-16) and Acid Black 1 (ABk-1). The adsorption isotherms were determined by comparing the experimental data with the isotherm models (Freundlich, Langmuir and Dubinin–Radushkevich models). The sorption capacity of the compost depended on the initial concentrations of dyes in the solution, compost dosage, and on the structure of dyes. The maximum sorption capacities of the compost for adsorbing particular dyes may be ordered as follows: ABk-1 > AG-16 > AB-9 > AR-18. The amounts of bound and the percentages of removed acid dyes from effluent depended on the adsorbent dosage. The growth of the dye removal percentages with growing adsorbent mass may be attributed to the growth of the adsorbent uptake surface with growth of the adsorbent mass. The dyes were bound onto the surface of compost through the electrostatic interaction between the surface (negatively charged at pH > pHPZC) and the dye cations (AG-16), and/or through the hydrogen bond between the functional groups of the humic matter in compost (–OH, –COOH) and the functional surface groups of AR-18, AB-9 and ABk-1 dyes (–OH, –NH2 ). At the experiment conditions, the Freundlich and Dubinin-Raduskevich adsorption isotherm models fitted the equilibrium data very well (much better than the Langmuir one). The values of 1/n in the Freundlich equation and E in the Dubinin-Raduskevich one indicate the favourable adsorption. The studied compost may be used as a low-cost sorbent for the removal of acid dyes from wastewater released by textile industries. However, elevated values of chemical oxygen demand (COD) in the final solutions may enhance the solubility of humic compounds.
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