Assessment of the Lowland Bog Biomass for Ex Situ Remediation of Petroleum-Contaminated Soils

Dmitriy V Tarabukin

doi:10.3390/environments7100086

Abstract

Bog petroleum-contaminated soils have been remediated ex situ in conditions close to natural ones. It was found that during the first 30 days in natural conditions, the decomposition of total petroleum hydrocarbons (TPH) was 30 ± 5%. On the 60th and 90th days, the process of TPH decomposition was 45 ± 5% and 60 ± 5%, respectively. The effect of various stimulant supplements was negligible. For the entire observed period, bog soil showed a very high self-cleaning potential with pollution concentration of 5 g of petroleum per 100 g of soil sample. Such diagnostic indicators of soil condition as urease and cellulase activities turned out to be most sensitive in the bog soil. The introduction of mineral fertilizers to stimulate the TPH decomposition increased the activity of urease in comparison with the background soil. On the other hand, the nonionic surfactant acted as an inhibitor of microorganisms involved in nitrogen metabolism, even in the presence of mineral fertilizers. The introduction of mineral fertilizers to petroleum-polluted bog soil stimulated the cellulases activity, while surfactants suppressed them in the early stages. The simultaneous introduction of surfactants and fertilizers kept the cellulase activity at the background level. It is concluded that in the case of petroleum pollution of infertile soils, the introduction of the upper layers of the phytomass of lowland bogs by providing looseness and long-term supply of nutrients from the dying parts of the moss will accelerate the self-cleaning processes.

Highlights

The use of imperfect technology and worn-out equipment for oil extraction, transportation, and processing results in penetration of petroleum into soil and aquatic ecosystems
The introduction of mineral fertilizers to petroleum-polluted bog soil stimulated the cellulases activity, while surfactants suppressed them in the early stages
For significant degrees of petroleum pollution, it is rational to use physical and chemical methods to remove most of the oil products that have seeped into the natural environment

Summary

Introduction

The use of imperfect technology and worn-out equipment for oil extraction, transportation, and processing results in penetration of petroleum into soil and aquatic ecosystems. Usinsk District of the Komi Republic is a region of intensive industrial oil production in the European North. In the autumn of 1994, the largest accident in the entire history of oil pipelines operation occurred on the territory of the Usinsk region of Komi Republic [1]. In countries such as Norway, Great Britain, and Canada, petroleum production takes place in similar natural and climatic conditions. For significant degrees of petroleum pollution, it is rational to use physical and chemical methods to remove most of the oil products that have seeped into the natural environment

Objectives

Methods

Results