Environmental Effects of Terrestrial Oil Spills

Historically, many of the largest oil spills in the world have been accidental terrestrial blow outs, geographically ranging from California to Persia and Russian Baku. Huge spills were also caused by sabotage and bombings in Romania during the World War I and in Kuwait during the Gulf War. Today, leakage from pipelines due to neglected maintenance and sabotage in Arctic Russia, in South America and in the Niger delta, account for most of the terrestrial oil spills. On land, oil kills vegetation and practically all soil-living organisms. When the lighter fractions have evaporated, the remaining heavy ones often form a surface reminiscent of a huge ill-paved asphalt parking place that prevents revegetation for many decades. Traces of oil can often be found a century after the spill. In freshwater, generally, the littoral zone is dominating and oil effects there are more important than those in the relatively small pelagic zone. Mollusks and crustaceans, together with water living insects, are generally hard hit and so are macrophytes. In mangrove stands, worms are among the most affected by oil spills, with barnacles often being the most sensitive. The mangrove trees sometimes succumb, when pneumatophores get oil covered, with resulting erosion.