carboniferous waste coal mining sludge, humus, heavy metals in sludge, fertilization
Abstract
The multifuncional role and importance of organic matter in soil is widely known. It is also known that the organic matter in soil is subjected to microbiological-biochemical processes of transformation, which includes synthesis of humus as well as it’s decomposition -mineralization. Mineralization means transformation-decomposition of organic matter by microbiological processes to mineral products; plant nutrients and water + CO2 as starting and ending component of photosyntesis. Nutrients are partly plant available with fertilizing effect, partly lost from the soil - leaching in ground water, causing it’s eutrophication, but CO2 in atmosphere participates in greenhouse effect. Practically, mineralization means decreasing of organic matter content in soil and soil degradation [1,4]. In natural ecosystems (phytocenoses natural forests and meadows), it is almost a balanced between inflow and consumption of organic matter, while the cultural and anthropogenic soils agrobiocenosis in general, this relationship is disturbed that there is a disproportion between the inflow and loss [1,4]. Therefore, various materials that contains organic material (waste, various flotation, sludge, etc.) are often used with more or less success. One of such materials, as well as the potential fertilizer, is carboniferous lake sludge like waste of coal mining sedimented at the bottom of the lake in huge quantities, which is the subject of our reasearch. The research were conducted to determine its fertilizing efects and value for repairing of physical and chemical properties of soil. The research refered to: -- Laboratory analysis of physical and chemical characteristics of the carboniferous sludge samples, -- Analysis of soil of the experimental field -- Research on heavy metals concentration in soil of the experimental farm and in carboniferous sludge, and Research of fertilizing effects of sludge, comparative mineral fertilizer and farmyard manure treatment by field trials with 4 variants and 4 repetitions. Soil and other laboratory research were conducted using standard methodologies using in soil science, while in the field experiments conducted using the exact field experiments [2]. Investigations were carried out on the culture of maize (Zea Mays) and lasted for one year (2009.). The results are encouraging because there had been a series of positive changes in the soil, yields of above ground mass mass and grain of maize were more than 50% (50,2%) higher compared to the control. The treatment applied lake sludge there was a series of positive changes in physical and chemical properties of soil. In particular, it significantly increased the content of organic matter or humus, from 3 to over 4% in the soil, humus content increased on average about 20%. The presence of heavy metals and other pollutants in carboniferous sludge do not exceed the maximal allowed concentration (M.P.S.), on the basis of instructions for defining the allowed quantities of harmful substances in soil and methodology of its analysis (the Gazzete of FBiH No 11/99). By this Instruction are identified the substances considered to be harmful for agricultural soil, the allowed quantities of harmful substances in soil, measures for preventing soil pollution and contamination control.
