[ricki]

You are welcome. So much depends on what quantities and in what state petroleum moves into the Straits of Florida. Prevailing easterly winds in the warmer months suggests a lot of shoreward transport once it makes it over here.

Oil is a powerful food source for some microbes. You can test sands above water and perhaps find modest concentrations of certain soil microbes. Spill some oil on it and shortly you'll have an explosion of naturally occurring microbes gobbling the stuff up like no tomorrow. They will continue to ingest and breakdown the petroleum until; 1) It is all gone. 2) Waste products from the microbes impair their viability. In the later case they poop or respire themselves to death, more or less.

Here's the rub and a potentially serious one. The deeper reaches of the ocean usually aren't oxygen rich nor are there typically water transport mechanisms over large areas to rapidly exchange oxygen depleted water with that with higher concentrations. So, dump a ton of oil into the deeps, you will likely get the normal population explosion of microbes including anaerobes. So, in addition to oxygen depletion you will also evolve hydrogen sulphide (particularly toxic to marine life) and more methane. I recall something about long term pollution in the Black Sea creating a major oxygen depleted (read "dead") zone in the water column at depth. Hope to God it doesn't happen but could something like this be in the works in the Gulf?

Worked with and around bioremediation for almost 25 years. Some of it works extremely well and almost automatically. Just supply enough nutrients, oil, oxygen, and avenues for waste passage and petroleum contamination depletion can be amazing. Some bioremediation over the years has amounted to so much "snake oil," high on promises low on practical delivery in some settings. Land farming is the most effective done on the surface for contaminated soil. In situ remediation of groundwater the least effective at least in South Florida using injected microbes and nutrients. On the other hand, over excavation of saturated petroleum impacted soils, UV degradation, mixing, even active aeration of the standing water in the excavation can be very effective in reducing groundwater contaminant concentrations.

Parallels in benthic bioremediation in the open ocean, you've got me. Again part of it happens automatically but to what ultimate end is more concerning. As far as wetlands, it may be more doable but also complex. Wholesale mortality in mangroves and other wetland components seems unavoidable with excessive exposure to oil. In the case of tar balls, depends how hardened, weathered they are and how they break up and physically interact with the prop roots (adhere to and smother them or ?). A major die off of estuarine vegetation followed by fauna depletions with lingering oil soil and sediment impact doesn't leave much to regenerate, near term anyway. There are also surrogates or breakdown daughter compounds that could provide problems too.