The paper presents analysis of influence of amount of pollutants, described as BOD₅, COD and total suspended solids, in the sewage from the cutting plant, butchery of pigs and from the tenants on their concentration in the sewage which flow into the treatment plant Bioblok PS-50 in Gruszow. Average concentrations of pollutants in the sewage mixture were calculated on the basis of the weighted mean. The disturbances of the treatment plant operation were found to be caused by too high concentrations of the above mentioned pollution indexes. On the basis of the calculated weighted mean the average amount of BOD₅ index was 592,1 mgO₂ ∙ dm^–3, COD – 974,8 mgO₂ ∙ dm^–3, whereas the total suspended solids 570,7 mg ∙ dm^–3. In order to decrease the concentration of pollutants in the raw sewage which flow into the treatment plant, should be enlarge the proportional participation of domestic sewage with 82% to 96%. Moreover the existing industrial sewage pretreatment system needs to be modernized or a new one needs to be installed in the exact place of the sewage origin.

Flora is one of the most important element in river valley landscape. The aim of the paper is characteristic of flora diversity and formulating directions for shaping Biała river valley. It was distinguished 46 plant species which were grouped into 7 plant species communities. These plant species are typical for river valleys without high interferences by man. Biała river valley has got important role as ecological corridor in Tarnów because of high natural values.

Vegetation is still modificated by environment and anthropogenic factors. It was presented few methods of disturbance vegetation research as: ecological indicator values of selected vascular plants according to Ellenberg [1991] and Zarzycki [2002], Ramienskij method [1956], vegetation degeneration according to Olaczek and Sowa [1972] Grime’a method [1979], hemerobia, system of degeneration phases Faliński [1966]. These methods are very useful in many disciplines for example monitoring, landscape planning, landscape architecture or agriculture.

The aim of the study was to define the scope of the spring snowmelt impact on the increase of inflow to the separated sewer system sewage treatment plant. The research was carried out from 1^st January 2010 to 31^st March 2010 in four selected sewer systems located in the Lesser Poland voivodeship. Hourly air temperature and daily sewage flow measurements were performed. Intensive snowmelts in 2010 began on 19^th February and ended on 4^th March. The average inflow percentage in the sewage discharge to each treatment plant during the snowmelt season reached from 36.6% to 58.1%. The highest inflows occurred on 1^st March (average daily air temperature – 6.6°C), and their percentage compared to the average daily flow at the rainless weather reached respectively: 56.8% in the sewer system A, 74.3% in the sewer system B, 54.7% in the sewer system C and 76.5% in the sewer system D. These numbers indicate that inflow caused by the snowmelts constituted over 50% of the daily flow in all analysed sewer systems. The following amount of inflow was discharged into the analysed sewer systems during the greatest snowmelts, i.e. from 19^th February to 3^rd March 2010: 3641 m³ into the sewer system A, 6926 m³ into the sewer system B, 1854 m³ into the sewer system C and 5846 m³ into the sewer system D. Openings in the inspection chamber manholes as well as illegal connections of gutters and yard inlets to the sanitary sewers were considered as the cause of melt-water discharge into the sewer systems.

Along the paper, we described research on chosen hydrodynamic parameters in near woody debris and downstream and upstream of obstruction river bars, which were formed within the area of the debris. Values of velocities measured in the field served to calculate shear stresses and other hydrodynamic parameters, which are characteristic for the process of the river bars formation. The study was carried out in the Raba River in the South Poland. The results show that the woody debris present on the river bed strongly influenced process of the formation of two channel bars and change the hydrodynamic parameters within the research reach.

Using the highland catchment of the Grabinka river located in the Wisłoka drainage basin as an example we assessed the capability of Snyder’s and Clark’s synthetic unit hydrograph (SUH) to simulate flood wave. Calibration for model parameters was based on a rainfall episode recorded in June 2006. We adopted the minimum of the objective function as an optimisation criterion. The quality of the models was evaluated using the efficiency coefficient E. Analysis showed that both Snyder’s and Clark’s SUH describe properly the observed wave, with the first model yielding somewhat better results. For both SUH the times to culmination were the same as for the observed wave, whereas the calculated culmination discharge differed from the observed one: for Snyder’s SUH it was 0.11% higher, and for Clark’s SUH 1.9% lower than the observed discharge.