The aim of this study was to analyse the applicability of infrared (IR) heaters (400 W, HTS/1 Elstein) to increase peat temperature of water-saturated peat. The experiment was carried out within two schemes. In VARIANT I the heaters were installed perpendicular to the heated surface at a height of 2.3 m, while in VARIANT II the heaters were mounted at a height of 2 m at the edges of the heated surface so that radiation reached the heated surface at an angle of approximately 40-50°. Based on the analyses of night-time means (from 3:00 to 6:00 a.m.) of peat temperatures recorded on manipulated plots under the heaters and the reference temperature, it was found that the application of HTS/1 heaters caused an increase of the mean peat temperature by 1.1°C and 0.5°C for VARIANT I and VARIANT II, respectively. The air temperature 5 cm above the heated surfaces was increased by 0.7°C and by 0.5°C at VARIANT I and II, respectively.
A comparison of the linear least-squares method and a trial-and-error non-linear method of three widely used isotherms (the Langmuir, Freundlich, and Redlich-Peterson) were examined in an experiment using lead ion sorption onto peat at different temperatures. The four Langmuir linear equations are discussed. Langmuir isotherm parameters obtained from the four Langmuir linear equations using the linear method differed but they were the same when using the non-linear method. Langmuir-1 is the most popular linear form, and it had the highest coefficient of determination compared with the other Langmuir linear equations. The Redlich-Peterson and Langmuir isotherms produced higher coefficients of determination. There are two separate regions depicting the Freundlich isotherm. The results show that that non-linear method may be a better way to obtain the parameters.
The experiment was carried out at the Department of Ornamental Plants in the Agricultural University in Lublin in the years 2000–2002. The plant material was corms of Acidanthera bicolor var. murielae Perry with a circumference of 8–9 cm, which in number of thirty was planted on a plot 1.2 m², at 8 cm of depth in the second week of May. According to the scheme of experiment: linuron 1.000 kg·ha⁻¹, pendimethalin 0.990 kg·ha⁻¹ and napropamide 1.500 kg·ha⁻¹ were applied one week after planting the corms of the research plant. Next day some plots were mulched with 5 cm thick layer of pine bark or peat. The experiment included also a control set without herbicides and mulches, which it was hand weeded and a control set with delay hand weed performed three week late compared with the rest plots. At the end of vegetative stage the measurement was carried out on 10 plants of each plot including: length of flower stem, number of flowers and length of spike. It was noted that linuron, pendimethalin and napropamide did not injury to plants of Acidanthera bicolor. Application of linuron and pendimethalin beneficially influenced on number of flowers (respectively by 9.65 and 9.72 pieces·plant⁻¹), length of flower stem (respectively by 102.54 and 101.52 cm) and length of spike (respectively by 40.14 and 40.28 cm). Besides application of napropamide had a positive effect on received of greater number of flowers (9.40 pieces·plant⁻¹) and longer spike (39.60 cm). Delay of hand weed about three weeks had a negative effect on yield and quality of flowers of the research plant which formed the smaller number of flowers and the shortest flower stems and spikes (respectively by 8.4 pieces·plant⁻¹, 96.2 cm and 35.4 cm). It was received the longer flower stems in combinations where applied of pine bark or peat as a mulch (respectively by 100.88 and 100.23 cm) in comparison with combination without mulch (97.96 cm). There was no noted considerably influence of organic mulches on number of flowers in spike and length of inflorescence.
Studies on sorption of heavy metal ions (Cr2+, Cu2+, Cd2+ and Zn2+) onto peats of defined type, sort, and kind, as a function of their physical and chemical properties, as well as determination of adsorbent-adsorbate binding stability have been carried out. Among the tested peats the best sorption properties have been found for low-moor peats: Humus Peat and Rush Peat, characterized by high decomposition rates (DR). Among studied heavy metals, the greatest chemical affinity to sorption sites showed chromium ions, bound onto organic matter in insoluble forms, the lowest - zinc and cadmium ions, which mostly enriched mobile forms.