The investigations were aimed to determine the probability of occurrence of sewage flows which are significant for the design, operation and modernisation of rural sewage discharge and treatment systems. The analysis included multiannual measuring data on daily sewage inflows to treatment plants from five rural sewerage systems located at Gdów, Koszyce, Kluszkowce, Łapanów and Stanisławice. The results showed that a sequence of daily sewage inflows to the treatment plants may be approximated by a theoretical log-normal distribution. The distribution parameters were estimated using a maximum likelihood method. The null hypothesis about the goodness of empirical fit of the daily sewage inflows to the theoretical distribution was verified using the non-parameter ?-Kołmogorow test. The parameters of theoretical distribution approximating the empirical distribution of daily sewage inflows from sewerage systems discharging sewage from 300 to 17 000 inhabitants are as follows: scale parameter -0.0999, shape parameter 0.4086. The calculated probability of exceeding the planned throughput of the sewage treatment plant to which sewage from the tested sewerage systems is directed revealed that the treatment plants at Kluszkowce and Stanisławice are overloaded in terms of hydraulics, and therefore require extension. At Kluszkowce 58.35% of all daily sewage inflows exceed the designed throughput and 26.75% – the critical throughput of the treatment plant, while at Stanisławice the respective values are 68.68 and 45.48%.

Basic hydraulic parameters such as shear stress, stream power, unit stream power and water velocities were calculated and measured within the region of a drop-hydraulic structure erected on the Kasinczanka stream in the Polish Carpathians. Besides examining the hydrodynamics of the stream, the study investigated also the distribution of grain sizes in the bed-load at the upstream and downstream aprons of the structure. It was revealed that grains deposited at the upstream apron were finer than those deposited at the downstream apron. At the same time, shear stresses and unit stream power values were found to be quite stable upstream of the drop structure, but to change significantly along the stream channel downstream of the structure’s energy-dissipating pool.

This paper presents a new procedure to obtain a continuous profile of overconsolidation ratio (OCR) by use of the cone penetration test (CPT). In the case of a cohesive soil the existing formulas described by other authors were presented and discussed. Some of them were then used to compute the OCR of a silty clay subsoil. The results were compared with the data of CRS oedometer tests carried out on undisturbed samples. In the case of non-cohesive soils a new device for CPT, a dilatocone, was used (DCPT). On the basis of the DCPT results new solutions were obtained enabling evaluation of the OCR of sand. They are based on the old formulas described by Kulhawy and Mayne and a completely new one, which gives the opportunity to evaluate the coefficient of earth pressure at rest (K₀). This new approach allows one to compute the OCR of a subsoil consisting of cohesive and non-cohesive strata and to observe changes in OCR along a continuous profile.

The paper presents the results of investigations into the physicochemical characteristics of rainfall and surface water from a drainage microcatchment situated in a submountaine region. This area is partly urbanised and has a mixed residential-agricultural-forest use. The samples of rainfall and outflow water were analysed for selected chemical components and physicochemical properties over a period of two years. The quality of both types of water was compared in the whole study period and between the vegetation and post-vegetation seasons, and the connection was defined between conductivity and the concentration of some chemical components. The results showed that the rainfall water contained a significantly smaller amount of the investigated components, except for some biogenic substances and suspension whose concentrations were higher than in the outflow water. Due to the excessive levels of the latter components (and Mn2+ in outflow water), however, both types of water were classified as off-class. In the rainwater the concentration of most components was higher during the vegetation season, while in the outflow water significantly higher concentrations of N-NO₃ and SO₄^2- were found during the post-vegetation, and BOD₅ – in the vegetation season. The conductivity of rainfall water significantly correlated only with Na⁺, K⁺ and Mg²⁺ content, and that of outflow water – with Cl^- and Mg²⁺.

The study presents the results of a 6-year hydrochemical research conducted in three mountain microcatchments having similar physical-geographic and climatic conditions but differing in land utilisation. The study contains a qualitative assessment of surface waters in agricultural and forest areas on the basis of 12 physical and chemical properties tested in partial microcatchments of the Trybska Rzeka stream situated in the Polish part of Spisz. The assessment was made by the guaranteed concentrations method, and the concentrations were calculated by means of the probability density function. The results of the tests show that the insufficient quality of surface waters in mountain agricultural-forest microcatchments is most often caused by the excessive concentration of biogenes, namely nitrogen and phosphorus compounds (phosphates), exceeding the threshold values acceptable for a specific water cleanliness class.

The effect of the level of fertiliser compounds in the soil on their concentration in drainage runoffs was investigated in an object situated in the Central Sudeten. The basic fertiliser compounds – NPK (available to plants) – were mostly accumulated in the upper layer of the soil profile. The soils under study contained a large amount of nitrogen and available phosphorus but a small proportion of available potassium. The drainage waters from the object had a high concentration of phosphorus, an average concentration of nitrogen and calcium, and low levels of potassium and sodium. An analysis of the results indicates that an increase in the fertiliser compound content of the top layer of soil does not necessarily lead to an increased concentration of those elements in drainage runoffs. In fact, the results suggest that the reverse might be true.

The paper presents monthly, seasonal and annual indexes and coefficients of outflow from two microcatchments (B and G) situated in the Beskid Mały Mts. During the period of investigations the mean annual air temperature was higher by 0.6 oC than the long-period average, while the mean annual sum of precipitation – 28 mm (B) and 78 mm (G) – lower than average. The mean annual outflow from the microcatchment G, 363 mm, and was by 105 mm lower than from B. The respective values represented 54% (B) and 44% (G) of the annual precipitation in the study period, indicating that the catchment B was more abundant in water than G. With both microcatchments, the outflow coefficient in the winter half-year was about two times higher than in the summer half-year. The values of half-year outflow indexes were only slightly different, but the summer precipitation was about twice as high as that of winter.

Studies were carried out in a wide flat valley located in the middle course of the Krasna River, which is flooded during excessive rainfall. The whole flood plain is dominated by the communities of hydrophyte plants, e.g. Phragmites australis, Phalaris arundinacea, Carex gracilis, Equisetum limosum, Molinia coerulea, Alopecurus pratensis, Holcus lanatus and others. After the inundation of 1997, surveys of the main plant communities were made in 1998 according to the Braun-Blanquet method and were repeated in 2002 on selected plant communities. The results show that the botanical composition of plant communities changed: the proportion of hydrophytes decreased and that of mesophytes increased in the sward, and even some xerophytes appeared. Due to those changes the river channel became overgrown, which hampered the outflow of surface waters from the valley. Another factor contributing to the increased bogginess of the valley was the improper operation of the weir damming up water for a local industrial plant.

The research determined the concentrations of cadmium, lead and zinc in the internal organs of hare from different regions of the Małopolska province that are threatened to a various degree with industrial pollution. It was found that cadmium accumulation in the animal kidneys may provide the best indicator of environmental contamination with heavy metals. The hare from the north-west areas of Małopolska accumulated several times bigger amounts of cadmium than the animals living in the “clean” areas. In the case of lead the differences were smaller while the zinc concentrations found in the organs of the studied hare did not differ from the average level of this element shown by terrestrial mammals.

Proper selection of plant species resistant to heavy metals and accumulating them in large quantities would promote phytoremediation methods in the reclamation of contaminated areas. Among species capable of taking up harmful elements and producing high yields are Jerusalem artichoke, maize, Sida hermaphrodita Rusby, amaranth and industrial hemp. Investigations carried out in 1997–1999 as a pot experiment in a plant house were aimed at analysing the effects of soil contamination with heavy metals (Cd, Cu, Ni, Pb and Zn) on the yield of the examined plants and the level of the metals they contained. The results showed that with increasing concentration of heavy metals in the soil their uptake by plants rose successively and depended on the plant species.

The aim of the studies was to determine which influence the public road No 4 running through the Dębica district has on the levels of some heavy metals (Cu, Zn, Pb and Cd) in the soils and meadow sward in the vicinity of that road. The results showed no significant contamination of the soil environment with the heavy metals studied. The observed enrichment of the turf layer of soil with zinc, lead and cadmium, as compared to the subsoil, was most probably caused by a point source of pollution and does not justify excluding these areas from agricultural production. The concentrations of heavy metals, except cadmium, in the grass sward taken from the soil-sampling site did not generally go beyond the limits specified for fodder. In the case of cadmium the value limiting the fodder usability of sward (0.5 mg ? kg^-1 d.m.) was exceeded at some points, which, howewer, does not justify the withdrawal of this fodder from use.

The aim of the study was to estimate the levels of trace elements in the grain and straw of bread cereals (wheat and rye) cultivated in Lower Silesia. 848 samples of grain and 680 samples of straw were analysed to determine cadmium, chromium, copper, iron, manganese, nickel, lead and zinc contents. The percentage of grain contaminated with heavy metals varied between subregions and was the following: the Legnica subregion – 11.4%, the Jelenia Góra-Wałbrzych subregion – about 10.2%, and the Wrocław subregion – about 2.3%. The sources of grain contamination in the Lower Silesia province were: cadmium (42%), lead (34%), and zinc (24%). About 2.2% of the straw tested is unsuitable for fodder utilisation because of an excessive cadmium content. The straw contaminated with cadmium comes mostly from the Jelenia Góra-Wałbrzych subregion. It follows from the results that about 10% of the grain of bread cereals cultivated in Lower Silesia will be unfit for human consumption owing to its excessive levels of trace elements. Instead, that grain can be utilised as fodder.

Samples of grain and straw of cereals (wheat, rye) and samples of grasses taken from the cultivated fields and grassland of Lower Silesia were analysed for arsenic and mercury contents. In the majority of samples the levels of both elements did not exceed the limits specified in Polish literature. However, the samples of cereals and grasses derived from the Legnica subregion contained higher amounts of arsenic and mercury than those from other subregions of the Lower Silesia province. Of the plants compared, grasses showed considerably higher levels of trace elements than cereals (grain).

Sulphur content was estimated in fruits and vegetables grown in Lower Silesia, such as apples, strawberries, cabbage, carrots, cucumbers and early potatoes. Based on the analysis of 2347 samples it is to be expected that with the present state of the natural environment about 5.7% of the crops of fruits and vegetables cultivated in this region will show excessive levels of sulphur. The limits of sulphur concentration were only slightly exceeded in the samples studied, which did not render the crops unfit for human consumption. However, their technological quality worsened making it difficult to store and process the products. Of the plants tested, cabbage followed by strawberries and cucumbers most often contained excess sulphur. Excessive amounts of sulphur in vegetables and fruits are more frequent in the Wrocław subregion than in other subregions of the Lower Silesia province.