Author/Authors :
markoska, vesna mit university - faculty of environmental resources management, Skopje, MACEDONIA , spalevic, velibor university of montenegro - faculty of philosophy niksic - department of geography, MONTENEGRO , gulaboski, rubin university goce delcev stip - faculty of agriculture, faculty of medical sciences, MACEDONIA
Abstract :
Perlite is a generic name for an amorphous volcanic rock that expands by a factor of 4–20 when rapidly heated to (760–1100°C). Water trapped in the structure of the material vaporises and escapes, and this causes the expansion of the material to 7–16 times its original volume. The expanded material is a brilliant white, due to the reflectivity of the trapped bubbles. Expanded perlite has several attractive physical properties for commercial applications, including, low bulk density, low thermal conductivity, high heat resistance, low sound transmission, high surface area, and chemical inertness. The perlite supplies the ideal balance between air and water. Perlite is sterile, inert, non-toxic, non-decomposable and easy to handle with, enhanced water retention and aeration capacity. The application of substrates which improve the properties of the soils requires knowledge of their physical and chemical characteristics that are responsible for providing adequate support and a reservoir for air, water and nutrients. Agricultural production is increasingly concerned about the study of the impact of improvers of properties, such as perlite, that affect the properties of soils as well as their impact on yield and plant quality. The goal of this paper is to observe the influence of porosity on the Perlite substrate and its interaction with the porosity of two types of soil and the peat substrate. The laboratory part comprised preparation of the substrate perlite, soils, and substrate peat for analyses and conducting quantitative laboratory analysis. The substrate perlite, soils and substrate peat were analysed in all five of their different ratios: Perlite (Pe) 20%; 30%; 50%; 70%; 80% by volume) and 100% perlite. Fluvial soil (FS) 80%; 70%; 50%; 30%; 20% by volume) and 100% fluvial soil. Mollic Vertic Gleysol (GS) 80%; 70%; 50%; 30%; 20% by volume) and 100% mollic vertic gleysol. Peat (P) 80%; 70%; 50%; 30%; 20% by volume) and 100% Peat. In laboratory conditions the total porosity (in percentage form) was determined with the help of apparent and specific density (apparent density through applying the Koppecki method (specific density was determined through the Gracanin method. The pores’ total content is determined indirectly on the basis of the specific mass and volume mass. The results will be displayed through statistical data processing.
