The work is an attempt to assess piped water quality in four counties located in east central Poland. Piped water was analysed for three successive years in each county. Water samples were tested for the following physical and chemical parameters: turbidity, colour, conductivity, taste, odour, pH, nitrates (III), nitrates (V), iron and manganese. They were compared with the current standard values. Preliminary data analysis included an analysis of maximum and minimum values of physical and chemical parameters, and it revealed that turbidity, colour, iron and manganese contents exceeded the permissible standards in all the counties. Percentages of parameters exceedances and mean values of the exceedances were used to rank the counties in terms of water quality. The ranking was obtained by means of multidimensional comparative analysis. It was demonstrated that best quality water was supplied by Węgrów County water supply system which was followed by Mińsk Mazowiecki County. The third rank was assigned to Łosice County and the poorest quality water was found to be supplied by Siedlce County water supply system.

Soybean ( Glycine max (L.) Merrill.) yielding potential depends on environmental conditions (precipitation, temperature, soil). The aim of the work was to evaluate stability of yielding (and other traits) of three soybean cultivars (Abelina, SG Anser, Merlin) grown under the climatic conditions of central-eastern Poland. The studied material was obtain in a field experiment conducted at Łączka (52°15' N, 21°95' E) during the growing seasons of 2017–2019. Trait stability was determined based on Shukla’s genotype stability variance and Wricke’s ecovalence describing the genotype-by-environment interaction. For all the examined parameters, there were found significant differences between successive growing seasons, cultivars, and cultivars within study years. The greatest influence of environmental conditions (years) was determined for plant height (64%) and first pod height (54.2%). Stability parameters indicated that cv. Abelina was the most stable in terms of yielding, 1000 seed weight, seed number per pod and average seed number per pod, cv. SG Anser being the least stable in this respect

The purpose of the work is to characterise pluvial conditions in central-eastern Poland from the beginning of the 21 ^st century (2001–2020). The analysis involved seven meteorological stations of the Institute of Meteorology and Water Management – National Research Institute (IMGW-PIB): Białowieża, Legionowo, Pułtusk, Siedlce, Szepietowo, Terespol and Warsaw. The work contains the analysis of the annual and seasonal atmospheric precipitation pattern (summer, winter, spring and autumn) and its temporal and spatial variation throughout a 20-year period. Moreover, the percentage share of precipitation in each season in the annual sum was calculated. In order to analyse precipitation patterns in the study period, the Innovative Trend Analysis (ITA) was applied. The average long-term annual atmospheric precipitation sum ranged from 557 mm at Terespol to 653 mm at Białowieża. The highest seasonal precipitation sum in the studied region was recorded for the summer (218 mm) whereas in spring and autumn, precipitation stayed at a similar level and amounted to 130 and 131 mm, respectively. The lowest precipitation was recorded in winter (109 mm). The highest percentage share of the atmospheric precipitation sum was associated with summer rainfall (from 35 to 38%), whereas the lowest in winter (from 18 to 20%). Comparisons of 2001–2010 and 2011–2020 decades revealed a decline in the share of summer precipitation in the annual sum at most of the stations, and an increase in the share of winter precipitation. The ITA demonstrated that the most significant trends in precipitation change occurred in summer and winter and the directions of the trends were different for each station.