In our article the ordinary kriging interpolation method was used for a spatial presentation of PM2.5 concentrations. The data used in the research was obtained from the unique PM2.5 measuring system, based on low-cost optical sensors for PM2.5 concentration measurements, working on Wroclaw University of Science and Technology campus area. The data from this system was used as an input for the interpolations that were made for three different days characterized by the highest measured values of PM2.5 – 20.01.2019, 17.02.2019 and 30.03.2019. For each of the selected days, variants with the maximum and minimum PM2.5 values recorded on a given measurement day were presented. In the analyses performed, the ordinary kriging technique and cross-validation, was used as the interpolation and the validation method, respectively. Parameters determining the quality of performed interpolation were Mean Error, Mean Standardized Error, Root Mean Square Error, and Average Standard Error. As the main indicator of quality of interpolation RMSE parameter was used. Analysis of that parameter shows that the higher variability of the data used for interpolation affects its quality. The Root Mean Square Error parameter reached 0.64, 0.94 and 1.71 for the lowest concentrations variants characterized by low spatial variability, and 6.53, 7.51, 11.28 for the highest one, which were characterized by high spatial variability. The obtained results of the research with the use of GIS tools shows that the ordinary kriging method allowed for the correct spatial presentation of the PM2.5 concentration variability in areas not covered by the measurement system.

Waste management faces more and more serious challenges, especially given the growing amount of municipal waste generated in Poland and the resulting environmental impact. One of the significant environmental aspects of waste management is the emission of odorants and odors. Taking into account the odor problem, the majority of municipal waste generated is being collected as mixed waste (62% of municipal waste), which by weight contains approximately 32.7% of kitchen and garden waste. These organic fractions are mainly responsible for the emission of odor and odorants. Those substances can be emitted at every stage: from the waste collection at residential waste bins, through transport, waste storage, and transfer stations, up to various respective treatment facilities, i.e., mechanical-biological waste treatment plants, landfills, or waste incineration plants. The gathered data during the study showed that it is necessary to increase the share of different waste management methods, i.e., recycling, composting, or fermentation processes rather than landfilling to meet all necessary regulations and to fulfill provisions of the waste hierarchy. One of the actions indicated in the legal solutions is expansion, retrofitting, and construction of new sorting plants, anaerobic digestion plants, composting plants, and increase in thermal treatment capacity. Variety of different processes that could emit odors and a diversity of different odor-generating substances released from particular waste management steps should be taken into consideration when building new facilities which are suitable for waste treatment. The overall aim of the work was to characterize and summarize available knowledge about waste management system in Poland and to gather information about odor-generating substances emitted from different waste management steps and facilities, which could be a potential source of information for preparing legal solutions to reduce possible odor nuisance form broadly understood waste management.