EJPAU, 2002, Volume 5, Issue 2
Environmental Development

This paper presents the results of a study of reversal hypothesis phenomena observed within riffles and pool sequences on a 1.1 km long reach of the Skawica-Jalowiecki Stream. The Skawica-Jalowiecki is a flashy mountain stream with an alluvial bed that transports sediment during frequent floods. The study reach is situated just below the border of the Babia-Gora National Park in Polish Carpathians, which provides a good, undisturbed research site. It was found that Q=4.27 m³s^-1, Q=2.43 m³s^-1 velocities and shear stresses in pools were highest over riffles during spring floods. It was also observed that unit stream power above the pools was bigger than that found in the riffles.

The presented paper is an edited version of Ph.D thesis of the same title and by the same author. The investigations were carried out in a small agricultural catchment area in the hydrological years 1998/1999-1999/2000. Four cross sections, above and below two small ponds of the total area of 0.8 ha, were subjected to daily bathometrical and hydrological measurements. For each hydrological year, the total suspended loads both supplied and carried out from the ponds were determined. The accumulation rate was analysed against the changeable water discharge and supplied sediment load. The changes in sediment yield values were analysed against the archive data from the years 1977/78-1993/94 in which no ponds were present in the area covered by the studies.

One factor field experiment was performed from 1992 to 1996 in Czyrna near Krynica (Low Beskid). Influence of the number of days without a plant cover upon intensity of soil losses was studied for 3 four-field crop rotations at a mountain side of average 13.5% slope. The content of plants displaying high soil-protective capacities contributed increasingly into successive crop rotations. The research has led to conclusion that soil loss intensity (y) is directly proportional to the number of days (x) at which the soil remained uncovered, counted from harvesting a preceding plant to sowing a proceeding plant that has been assessed. The relationship can be described by the following a regression equation: y = 0.168x + 9.828 [kgˇha^-1ˇyear^-1]; n = 136, á = 0.01; r = 0.723.

The effect of UV radiation on absorption, fluorescence spectra and dynamics of phototransformation of five different humic acids (HA) of natural and synthetic origin were investigated. Two types of synthetic HA were prepared: one containing only C, H and O atoms, and another with content of C, H, O and N atoms. Natural HA were also diversified with respect to their origin. We used UV-C radiation (predominantly the wavelength of 254 nm) to provide a wide spectrum of photochemical mechanisms.

The influence of various concentrations of salts of lead (II), copper (II), manganese (II), cobalt (II), molybdenum (IV) and iron (III) upon the soil dehydrogenase has been studied. Ecological areas featuring the contamination degree to which the studied soil environment had been exposed have been determined. Particular attention has been paid to high heavy metal doses causing significant disturbance to soil metabolism.