Question 4: What's happening to coastal ecosystems?

Coastal wetlands in the Gulf of Mexico have been under siege for decades. Chronic exposure to large amounts of oil could worsen their plight, killing marsh grasses and the creatures that live in the coastal sediment.

Three weeks ago, academic researchers took sod samples from an established field site just east of the Mississippi River. Now they plan to collect oiled sods from the same site and, in a greenhouse lab, compare processes such as plant growth, photosynthesis, and soil respiration. In June or early July, the same team plans to survey sedimentation rates at 18 sites along the wetlands west of the Mississippi, an area likely to be hit by oil. A third study would assess the effects of fresh and weathered oil on different species of marsh plants; scientists say oil that has seeped into the soil and comes in contact with roots could have greater long-term impacts on vegetation than oil slicked on the surface.

In the shallow waters of Louisiana's Breton Sound, where oil has already intruded, effects on marine life may already be visible. A team will collect live mollusks for tissue analysis, examine their shells for changes in growth rates, and look for deformities in the husks of foraminifera, an amoebalike bottom-dweller, and for large numbers of hibernating dinoflagellates in the soil.

Back to "Five Questions on the Spill." | Next question: What's happening to fisheries?

  1. What's happening with the oil?
  2. What's happening to life on the sea floor?
  3. What's happening to marine life?
  4. What's happening to coastal ecosystems?
  5. What's happening to fisheries?