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Ryan P.
Fannin
1st period
14 May 2002

Lake Lafayette is located on the east side of Tallahassee, Florida. It was divided into three parts by man in the 1960s, the middle of the three parts is Piney-Z Lake. The type of land around Lake Lafayette is called Karst topography. This geographical term is

referred to land that contains limestone areas, which possess topography dependent on the diversion of surface waters to underground routes. It is used for areas like Lake Lafayette that have sinkholes or aquifers in its vicinity. The picture above is of Lake Lafayette, you may be asking why it is dry. Well, when man decided to divide the lake into three parts there were some problems. Lake Lafayette contains many sinkholes, one of which is in the northernmost part of the lake and is the biggest sinkhole. The water in the lake eventually drains out leaving a very fertile plain. The water goes into the Floridian aquifer to become drinking water. (YUMMY!)

Eutrophication is when a gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake occurs. This has happened in Lake Lafayette, especially Piney-Z. This is harmful to the life in Lake Lafayette because when all the nutrients build up, often on the surface, prevent light penetration and oxygen absorption necessary for underwater life. A type of eutrophication is called cultural eutrophication. This is when man speeds up this process by allowing excessive amounts of nutrients, such as fertilizers and sewage to enter the ecosystem. Man contributed to this by dividing the lake into three parts. This division settled the water causing all the

There are certain water parameters that are important to maintaining Piney-Z as an urban fishery: temperature, dissolved oxygen, pH, turbidity, phosphates, and nitrates. We, as people do not like our environment to be certain temperatures, and in some instances cannot live in them either, whether it is too hot or too cold. To maintain an urban fishery, it is the same thing; organisms cannot live in too hot nor too cold water. Just like land creatures, organisms in the water need to have oxygen to live. Too much or too little oxygen can kill a fish. Maintaining it at a specific level will keep the fish from dying. Maintaining the pH level is important because. Turbidity is when all the stuff in the water is stirred-up forming the cloudiness of water, this is not good because sometimes light will not go through leading to the plants not being able to produce very much oxygen. Phosphates and nitrates are important in the water, but man likes to add more (fertilizers and animal waste products) so too much can be a problem.

At Piney-Z, we measured: temperature, dissolved oxygen, and pH. For all three, by the end of the year we used electronic devices along with the dissolved oxygen kit. For pH and temperature, we just stuck a probe into the water and the graphing calculator picked up the recordings. For dissolved oxygen, we used a kit that obtained the readings from various solutions and tubes. We used drops to finally record the dissolved oxygen.

All of these water parameters need to be kept in check. Man has altered them too much. The turbidity and dissolved oxygen kind of go hand in hand; when the lake was divided, they went way out of control due to the build up of suspended junk. This prevented much oxygen to be produced because sunlight could not penetrate that well.

The past has looked pretty bad for Piney-Z Lake. The division of Lake Lafayette caused problems in the ecosystem. The water could not be circulated due to the dikes that were placed in it. The City of Tallahassee has tried to improve these conditions in recent years. They have drained the lake and cleaned it out, and hope in the near future to turn it into a fishery. These hopes are very close to becoming real.

Web sites used:
http://search.eb.com/eb/article?eu=33892&tocid=0&query=eutrophication