Monitoring of ecosystems in an oil-extracting area

Abstract

Complex monitoring has been carried out by five institutes of St.Petersburg Scientific Centerin on of the oil-fields, located in boggy landscape in the Western Siberia. The aim ofinvestigations is to estimate the conditions of land and water ecosystems around drilling wellsand in oil-extraction zone. Field work was performed in the surroundings of boring grounds atdifferent technological stages: 1) sand road pads construction, 2) drilling of wells, 3) wellsunder exploitation (oil extraction stage). During the field work the laboratory investigationsand chemical analyses of soil samples have been made. The state of soil and vegetation cover,soil microbial community, entomofauna, hydrobionts, ground vertebrates and birds has beenstudied. Soil microorganisms, plants, animals, hydrobionts have been used as bioindicators.Local changes of the components of environment caused by natural and technogenic factorswere found. Typical changes in ecosystems caused by impact of different technogenicdisturbances (oil spills, salt waters, technical oils, drilling muds, flooding by ground waters)were determined. The results of our investigations showed that the level of changes ofecosystems caused by technogenic impact was determined by three factors: the direction andintensity of impact, its duration and ecological resistance of ecosystem on a whole. Alongwith uniformity of technogenic impact in the different types of ecosystems, differentdeviations in their condition have been observed. In spite of rather pronounced deviations inthe condition of different components of environment the determined changes in the mostcases have the reversible character.