February 25, 2009

Nutrient cocktails create water woes

Published in the Crystal River Current on Wednesday, February 25, 2009.

Nutrient cocktails

Remember? Lyngbya algae needs a cocktail of nutrients to grow – Nitrogen, Phosphorus, dissolved Calcium and a dash of Iron.

Rain water falling through the air gathers carbon dioxide gas. On the way down to earth, weak carbonic acid is formed. On the ground humic acid, from rotting vegetation, combines to make a natural solvent for limestone rock. As that water soaks into the bed rock, the acids dissolve small portions of the limestone calcium. Holes left in the rock enable the solution to remain in the rock, much like a sponge holds water. As the dissolved calcium solution later finds its way into surface waters it becomes the basis of our nutrient cocktail.

Pyrite (iron) is a common mineral in marine sediments, and so is common in Florida's limestone. A natural chemical reaction deposits iron trace elements into the groundwater for the cocktail.

In the wild, bird droppings can supply the phosphorus, and, Lyngbya itself can fix nitrogen from the air we breath. Should a handy pine forest leach nitrogen into the ground water, that too can contribute to the cocktail.

(To think, we burrow miles underground to extract fossilized oil or gas. Break it down in huge chemical plants. Treat it with deadly chemicals to end up with nitrogen fertilizer!)

However, as we apply too much fertilizer for our plants to absorb (trying to make grass and plants grow faster and greener) the surplus drains away into our aquifer waters, which supplies nitrogen and phosphorus to the nutrient cocktail.

Also, mining the limestone for cement and road ballast, or to produce phosphates to include in our fertilizers, or even use in our dishwashers, harms the aquifer and reduces the water supply we cannot do without. Dumping mining waste and excess fertilizer into the Gulf of Mexico, stimulates red tide, or creates a “dead zone” there, where nothing will grow.

Spiking up the cocktail with mineral elements from our vehicles, really makes Lyngbya grow like crazy! (Too much drink makes man ill: excess nutrients harm water quality).

Next time, we'll discuss underground water flows.

Norman Hopkins. Director, Kings Bay Association, Director Amy H Remley Foundation Inc.