One of the consequences of the dynamic technological development is the rapidly increasing amount of electro-waste (WEEE, e-waste). Because there are no uniform legal regulations regarding the ways of collecting such waste, the separate-collection systems used in various areas are not homogeneous, and they usually also differ in effectiveness. The aim of this study was to evaluate the electro-waste collection system implemented in Lublin (the largest city in Eastern Poland). Taking into account the fact that the reliability of a collection system depends on the degree of its adaptation to the functions it performs, the evaluation consisted in determining how big a problem improper electro-waste segregation was. The article presents the results of a study of the causes of citizens’ failure to properly manage e-waste and indicates what measures should be taken to amend the problem. During two research steps, 347 pieces of e-waste with a total weight of 77.218 kg were found in the analyzed waste samples (0.33% of all samples). This means that the mechanisms of selective e-waste collection still do not work correctly, despite the ten years of Poland’s membership in the EU and implementation of European legislation in this area. The fact that residents throw away electric waste into municipal mixed waste containers poses a serious problem for proper waste management – even if only a part of the e-waste is disposed in this illegal way. This indicates the necessity of improving waste collection (more frequent waste reception, convenient access to e-waste containers, raising public awareness, etc.).

The substrates to biogas production in anaerobic digestion, except plant materials, can also be animal feces and manure. It should be highlighted that Poland is one of leaders in the European Union in animal breeding. However, there is no precise data in the literature on the potential of biogas production from animal feces in this country. The aim of the paper was to analyze the biogas production potential from manure in Poland. The aim of work included anaerobic digestion research following materials: cow manure, pig manure, poultry manure and sheep manure. In the next step, based on the obtained results of the biogas yield, energy potential calculations were made. The methane yield for the investigated feedstock materials in the batch culture technology was performed following the internal procedures developed based on the adapted standards, i.e. DIN 38 414-S8 and VDI 4630. Animal wastes were obtained from the Agricultural Experimental Stations of Poznan University of Life Sciences (Poznan, Poland). On a base of achieved results it was concluded that tested substrates have a high energy potential (approx. 28.52 GWh of electricity). The largest potential for electricity production was found in chicken manure (about 13.86 GWh) and cow manure (about 12.35 GWh). It was also shown which regions of Poland have the best chance for development of agriculture biogas plants (Wielkopolskie and Mazowieckie voivodships) and where the potential is the least (Lubuskie and Opolskie voivodeships).

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.

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.

The paper contains a micobiological characteristic of sewage sludge composted in controlled conditions together with bio-wastes (straw, sawdust, bark). An experiment was carried out in which the composted material was mixed up in adequate weight proportion and placed in biorcactor chambers with a constant air flow. The composting process aimed at defining the development dynamics and the survival of pathogenic microorganisms in the sewage sludge composted with different additions in a cybernetic bioreactor. Samples of compost necessary for microbiological analyses were taken at the same time, in reference to the actual temperature value. Bacteriological studies were carried out on selected substrates by plate method determining the number of pathogenic bacteria from the species: Salmonella, Clostridium perfringens, as well as from Enterobacteriaccac family. In the experiments, the presence of living eggs or intestinal ATT pathogens was determined by floatation method, as well. Il was found that the sewage sludge used in composting process did not contain any Salmonella spp. bacteria or any living eggs of intestinal ATT pathogens. Composting process completely eliminated the number or bacteria from Enterobactcriaccae family, bul it did not contribute lo the elimination of Clostridium perfringens bacteria. On the basis of the obtained results, it was found that the elimination of the studied groups of microorganisms, in all studied composts took place with the increase of temperature. In the case or Enterobacteriaceae, it was found that their complete removal from the composted material took place in chamber K3, while in the remaining chambers, it followed 48 hours later. Elimination ofthe vegetative forms ofC!oslridium perfringens bacteria followed after 96 hours of composting, in all composts at the same time. The obtained composts met the sanitary norms according lo the regulations of the EC Commission No. I 85/2007 of February 20, 2007 which changed the regulation of WE No. 809/2003 and WE No. 810/2003 referring to the extension of the validity period of transitional means for composting plants and biogas producing plants according to the instruction orWE No. 1774/2002 of European Parliament and Council and according to the instruction of the Minister for Agriculture and Country Development (2004).