The Effects of Waste Gas Flares on the Surrounding Vegetation in South- Eastern Nigeria

Throughout the Nigerian oil fields, large quantities of gas are produced. This gas contains about 900 . methane and is difficult to liquefy and transport. It is therefore burned off, at the flow stations above the oil wells, using stacks 7-9 m high. The stacks in this study have burned uninterruptedly for over three years, and there is considerable speculation among local farmers about the possible effects of these flares on the surrounding crops and vegetation. Air analysis (Shell-BP Internal Memorandum 1972a, b) indicated almost complete combustion of gas (hydrocarbons <0.001%0 at 45 m from the Rare). There was no appreciable increase in the CO2 content of the atmosphere at this distance. Preliminary observations (Sanford 1974) indicated little or no effect on the moss and lichen cover of tree boles except on trees very close to the stacks. The primary aim of the present study was to determine whether flares significantly affected the surrounding vegetation, but some measurements of the physical environment were also made in an attempt to interpret any effects on plants.