Alteration of Organic Matter by Gas Flaring Activity: A Case Study of Utorogu Community in Niger-Delta, Nigeria

Abstract

The Niger-Delta area of Nigeria is endowed with petroleum resources. However, her environment has been degraded through oil exploration activities. The soil has been exposed to serious varying degrees of heat effects due to the flaring of residual gases at the different gas plants/flow stations situated within the various oil producing communities. Several literatures have revealed that heat impacts negatively on soil properties, such as organic matter, total available pools of organic carbon, nitrogen, etc. Although some studies exist on the pollution status of the region, the situation of a number of communities has not been investigated. This study therefore, examined a three year (1998-2000) profile of organic matter, organic carbon, total soil nitrogen and carbon-to-nitrogen ratio as a function of distance from flaring epicenter and depth from soil surface within the Utorogu community using standard analytical techniques. Soil samples were collected during the dry and wet seasons at variable distance away from the flaring epicenter (downwind)- 20 m, 200 m, 1000 m and 5000 m respectively; and at 0-15 cm and 15-30 cm depths from the soil surface. The results of the study show variations with depth, season and distance. Across the various years, distance and depths, the mean values of the determined soil properties range as follows; soil organic matter: {Below detection limit-3.63% and 0.66-2.13%; Below detection limit-3.68 and 0.27-2.31; Below detection limit-7.20% and 0.10-2.18%}; organic carbon: {Below detection limit-2.11% and 0.13-1.22%; Below detection limit-2.17% and 0.07-1.30%; Below detection limit-2.20% and 0.11-1.28%}; total nitrogen: {Below detection limit-0.43% and 0.02-0.24%; Below detection limit-0.48% and 0.11-0.36%; Below detection limit-0.51% and 0.09-0.31%}; and carbon-to-nitrogen ratio: {Below detection limit-5.00 and 4.50-6.50; Below detection limit-6.58 and 3.50-6.49; Below detection limit-5.38 and 2.75-5.80}, for both the dry and wet seasons, and for the years 1998, 1999 and 2000 respectively. This study reflects potential environmental impacts of gas flaring within a typical oil producing community.

Keywords: Niger delta area, Petroleum resources, Oil producing communities, Downwind, Below detection limit