Use of zeolitic material from munella region (Albania) as fertilizer in the sandy soils of divjaka region (Albania)
Résumé
In Munella region, Albania there arc important zeolitic resources, which have various applications in agriculture. The zeolites in this area have been used in experiments as fertilizers in the sandy soils of Divjaka region (Central-western Albania). Lolium multiflorium was used as experimental plant. The experiment was realized in the green - house of the Tirana Agricultural University. Natural zeolites of Munella occur as separate layers hosted by andesite-dacite volcanic sequence of the eastern-type Albanian ophiolites. The zeolite assemblage consists of Stilbite-Stellerite solid-solution. Their cation-exchange capacity ranges from 192-242 meq/100g. They have strong affinity for the cations of Pb2+, Cu2+ and Zn2+ up to their concentration in solution. On the other hand, the respective concentrations of the introducing cations in zeolite are 137, 81 and 65 meq/100g, which are below the above measured cation-exchange capacity value. Sandy soils of Divjaka are undeveloped soils. They are characterized by small thickness of active layer, low content of humus and other essential nutriments of plants. These soils have homogeneous mechanical and mineralogical composition because of their uniform parental material, mainly composed by quartz of sea-sediment formations. Different combinations (seven) of Munella zeolites with chemical fertilizers (NPK) are experimented in order to study the impact of zeolites in the increase of fertility of the poor sandy Divjaka soils. The faster growing rates of plants, more healthy plants and greater number of individuals observed in the case of zeolite-treated plants are some of indications that evidence the role of zeolite as fertilizer. In addition, the "buffer" role of the zeolites in improving the water capacity of soils is observed especially during the most dry period of the year (July-August). ne variant with zeolite is distinguished for a longer conservation of soil humidity and. consequently, giving more healthy plant.