Biodegradace ropných látek v zeminách

Abstract

The thesis refers to problems of petroleum substances’ biodegradation in soils. Attention is dedicated to a manner of biodegradation process assessment, especially then problems of so-called biomarkers as an evaluation parameter of degradation efficiency of the above-mentioned substances. A theoretical part of the thesis is focused on evaluation of available literary information on petroleum substances’ biodegradation, biomarkers existing in petroleum substances and a laboratory methodology of their identification and determination. An experimental part of the thesis is paid to monitoring of biodegradation process in the soil contaminated by chosen petroleum substances by means of laboratory tests. Beneath the biodegradation term is understood involvement of biological factors within processes associated with degradation, transformation, optionally with immobilization of pollutants burdensome the environment. Biodegradation process efficiency is evaluated by analyses of series of microbiological and chemical parameters, which are commonly used for its monitoring in practice (e.g. determination of polluting substance concentration expressed as non-polar extractable hydrocarbons). Newly biodegradation process is assessed by force of biomarkers. Biomarkers are compounds from an isoprenoid family present in petroleum substances, which are applicable to own substance description and consequently to biodegradation process specification. So-called biomarker indexes are used for this description. Most frequently they are based upon determinations of pristane and phytane content but also of hopanes and steranes. The gas chromatography with a flame ionization detector (GC/FID) and/or a mass spectrometry detector (GC/MS) are used for monitoring of state of petroleum contamination by means of biomarkers. Selected aliphatic (e.g. pristane and phytane) and polycyclic (e.g. hopanes and steranes) isoprenoid hydrocarbons are observed. The aim of the laboratory biodegradation of chosen petroleum substances is to verify feasibility of biomarkers’ utilization as the evaluation parameter of biodegradation process.