The trends of changes in the maximum and minimum annual discharges, taking place in the years 1984–2000, were analysed for two catchments differing in the land-use pattern: a forest catchment of the Czartusowa river up to the „Szklarnia” gauging station, and an agricultural catchment of the Branew river up to the „Flisy” gauging station. The maximum discharges (WQ), regardless of the character of the catchment, showed on increasing trend, while the minimum discharges (NQ) tended to decrease in the forest catchment devoid of springs and to increase in the agricultural catchment supplied with water from springs. It was found that in the agricultural catchment droughts last longer, especially in the summer half-year, but their frequency is lower than in the forest catchment. Floods occur more frequently in the agricultural catchment and their number, as in the forest catchment, is twice as large in the winter than in the summer half-year.

A five-year research investigated eleven quality indicators of precipitation water and water flowing away from an agricultural microcatchment located in the foothills of the Beskid Mały Mts. The amounts of rainfall and outflow were measured every day and the water samples were taken once a week. Most of the quality indicators had higher values for the outflow water than the precipitation water. The mean concentrations of chemical components in precipitation water were slightly greater in the non-vegetation season whereas those in outflow water were similar or varied less between the seasons. The mean annual loads of components carried away by outflow were greater than those delivered by rainfall, except for N-NH₄ and PO₄^3- that showed an opposite pattern. In the vegetation season both the loads delivered by rainfall and the loads carried away by outflow were higher than in the non-vegetation season.

The results of studies conducted in the years 2003–2004 were used to carry out an ecomorphological evaluation of the Elżbieta Canal located in the Olsztyńskie Lakeland. The evaluation was made on the basis of the following parameters: bed morphology, watercourse hydraulics, physico-chemical properties of water, features of the tree-cover of banks, features of the aquatic and bank vegetation, features of the littoral zone, and land-use pattern of the surrounding valley. The Elżbieta Canal was divided into five sections. The results of the studies indicate that the naturalness of water decreases as the canal comes nearer to its mouth. Based on the average score for the whole canal, which was 2.86, it was assigned to naturalness class III that includes partially regulated watercourses of average ecological and landscape value. With respect to ecological and morphological value the canal clearly divides into two sections. The most valuable parts are located above the Kaplityny village, while below the village and further up to the canal mouth to the Wadąg Lake, the ecomorphological value of the canal lowers. The growth of housing estates in the close vicinity of the canal negatively affected the littoral zone, the aquatic and bank vegetation as well as the morphology of the canal bed and the quality of water.

A new air quality index (W_jp) was employed to assess air pollution in seventeen localities in the Łódź province. The index was worked out using data on sulfur dioxide, nitrogen dioxide and suspended dust. Calculations were based on the results of measurements performed in the period 1995–2000 as a part of the National Environmental Monitoring. For each locality, dimensionless coefficients (W_pa) of the ambient concentration of each pollutant were calculated and then added up to obtain the W_jp index for the locality. On the basis of W_jp values the localities were divided into three air quality classes. According to this classification, the localities showing the highest air pollution with the three substances considered are large and medium towns such as Opoczno (3rd, poorest class), and Łask, Tomaszów Mazowiecki, Sieradz and Kutno (2nd class).

For forecasting purposes the relations between the concentration of sulphur dioxide in the air and some basic meteorological elements such as air temperature and relative humidity, wind direction and velocity, and precipitation were studied using data from the atmospheric monitoring station of the Warsaw Agricultural University, located in Ursynów – a peripheral, southern district of Warsaw, and from the Geophysical Observatory of the Polish Academy of Sciences, situated in Belsk Duży, in a rural area. The studies covered the period of October 1997 to December 2002. The paper provides main statistical characteristics of SO₂ concentration; mean values of this concentration as dependent on wind direction, wind velocity and air temperature; as well as regression equations describing the connection between SO₂ concentration and meteorological elements, and correlation coefficients of these equations. The most frequent independent variables in the equations are wind velocity, air temperature and relative air humidity. The relationships for the urban area differ from those for the rural area. In the case of Belsk the correlation coefficients between SO₂ concentration and meteorological parameters are similar (in the range 0.41–0.60) whereas the coefficients for Ursynów show a wider variation (in the range 0.50–0.81).

Research carried out at a 15th-century wooden church in Dębno Podhalańskie was aimed to identify the threats that may be posed to the building by the variation in its inner microclimate which is influenced by the outer climatic conditions. During three years, temperature and relative air humidity were measured inside and outside of the church. This provided the basis for establishing the periods that are particularly unfavourable for the building and its interior, and assessing the effect that tourists and people attending worships have on the inner microclimate of the church. Some preventive measures were suggested in the form of practical recommendations. The measurements were performed using electronic temperature and humidity sensors. It was found that the inner microclimate depends very much on the outer weather conditions. Strong and long-lasting changes that occur in air humidity inside the church adversely affect its polychromy. High humidity is conducive to the growth of wood-invading fungi, bacteria and mould.

The paper describes the execution and the results of the quantitative chemical analysis of bottom sediment samples and the determination of their phase composition, grain size distribution and organic particle content. The sediments came from a fish pond located in the vicinity of Kraków. The investigations were caried out using both conventional methods and modern techniques of instrumental analysis such as thermogravimetry, mass spectrometry, scanning electron microscopy, X-ray diffractometry and grain size analysis. A method was proposed for calculating quartz content on the basis of an analysis of the thermal effect that occurs during the heating of the sample. It was found that the use of various methods of instrumental analysis makes it possible to obtain reliable data by substantially eliminating the influence of the researcher on the results.

Laboratory studies performed using a rotational viscometer with two coaxial cylinders were aimed to define the rheological properties of sludges coming from typical mechanical-biological treatment plants for municipal sewage, and to develop a model describing the rheological behaviour of the sludges. The concentration of solid parts in the investigated sludges ranged from 2.21 to 6.56%. The approximation of the true flow curves determined on the basis of experimental apparent flow curves was made according to the equation provided by Krieger, Elrod, Maron and Švec. To describe rheological characteristics the 3-parameter Herschel-Bulkley model was chosen. The study established the relationship between the rheological parameters of the model (τ₀, k, n) and the mass concentration (C_s). The critical concentration (C_s,gr) for the sludges was found to be 0.75%. The results of the research enable the dimensioning of the activated sludge pumping system of a sewage treatment plant.

The study attempts to assess the impact of climate change on the water resources of a light soil in the initial vegetation period of plants that is extremely important for their further growth. The use of a spatial weather generator together with the GISS climate change scenario offered a wider look at the incoming changes in soil water resources in the region of southwestern Poland. The means and standard deviations of soil water resources expected for three sites: Wrocław-Strachowice, Leszno-Strzyżewice and Zielona Góra in the year 2050 were compared with the actual values, showing the long-term trends in these resources.

A three-year field experiment carried out on a light soil in the Wrocław region was designed to examine the effect of sprinkling irrigation and nitrogen fertilisation with different rates on the amount and structure of the grain yield of brewing barley cv. Scarlett. It was found that weather conditions had the greatest influence on the yield. The weather-induced yield differences between the years reached even ca 18.6 dt · ha^-1 (55%). The mean yield increase in the study period, due to irrigation, was 3.6 dt · ha^-1 (8.6%). Sprinkling irrigation caused also a rise in the number of spikes per square metre and the weight of grains from a spike. The grain yield increased with increasing nitrogen rate and the difference for the extreme fertiliser rates attained 6.9 dt · ha-1 (16.4%). The rate 93 dt · ha-1 produced the largest number of spikes per square metre, and the rate 68 kg N · ha-1 – the greatest weight of 1000 grains and of grains from a spike.