A study published in the Soil Science Society of America journal looked into how crude oil from the 2010 Deepwater Horizon oil spill continues to affect the coastal marshes in Louisiana.
Although the Deepwater Horizon oil spill occurred more than seven years ago, the effects of the disaster are still evident to this day.
In the Louisiana coastal marshes, crude oil from the spill that has not degraded remain buried beneath the pile of dead plant material, which accumulates yearly after every season. Its proximity to the plant roots causes stress to the plants.
When the wetland soil is drained-for instance, during low tide-the crude oil slows down the transport of oxygen to the root zone. This delay adds to the stress levels of the plants in the area, which is already experiencing accelerated loss of marsh area due to high relative sea level increase.
The effects of this reduction is not as marked under flooded conditions which can occur during high tide conditions, for instance.