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Aaren E.


Aaren E.
May 16, 2002
Mr. Fannin
Piney Z Project: Narrative

Natural and Cultural History of Lake Piney Z
The land on which Lake Piney Z sits was originally a prarie. The lake itself was created for the pleasure of a private owner in the 1950s to serve as a hunting and fishing outlet. Little planning and consideration for the future took place during the making of this lake probably because the owner was not totally aware of the effects such a change to the environment would create. The area was blocked off and converted into the lake it is today. Introducing fresh water to the lake created a bustling fish population for years, but eventually the number of these dwindled because the fish could not reproduce as a result of low levels of oxygen in the water due to "problems with dense stands of aquatic plants, poor water quality and a layer of muck on the bottom [due to eutrophication] that was up to four feet deep in places." A buildup of dead aquatic plants at the bottom of the lake hindered the reproduction of fish introduced into the man-made environment.

Fifty years ago, the Piney Z area was uninhabited and nothing but a woody plantation on the map of Leon County. Today, it is the busy, bustling site of a rapidly-growing community. More and more houses are being built on the 407 acres of land surrounding the lake. Man's encroachment on the land has created a concern for the lake's health. The city of Tallahassee commissioned the Florida Fish and Wildlife Conservation Commission to evaluate the lake's condition soon after it bought it and the surrounding land. A conclusion was reached to "completely drain the lake, dry out the lake bottom as much as possible during an extended drawdown, and re-stock the lake with game fish," due to the lake's poor condition.

Depending on the lake, eutrophication, the "aging of a lake by biological enrichment of is waters," can occur over a span as long as thousands of year by two ways: natural eutrophication and cultural (or man-caused) eutrophication. When
eutrophication occurs, the growth of aquatic organisms and the lake's fertility increases. This natural process of eutrophication usually positively affects the lake, its living inhabitants, and the surrounding area. But when eutrophication creates an overstimulation of algae growth, as a result of sewage and agricultural and industrial waste that act as surface plant fertilizer, problems arise. The affected lake may begin to emit unpleasant smells and harbor unsightly scum; it may also be deprived of dissolved oxygen, vital to aquatic organisms, and contain pollutants that poison fish. Piney Z lake had witnessed similar effects as a result of a buildup of muck on the lake's bottom. As surface plants and algae died away and decomposed at the bottom, they began to pile up. The aquatic organisms and plants' dissolved oxygen levels were depleted and it was harder for the aquatic creatures to survive.

As we have discovered through our research, events have taken place to improve the lake's condition and it is expected to be open to the public very soon under the name, Piney Z Fish Management Area. The lake was drained and 25% of its bottom scraped of the black muck that strangled it. In the future, it can be expected that despite the fact that an increase in those inhabiting the area will occur, an increase in the concern for the lake will also take place. The area will most likely become less woody and more "people-friendly."

"Karst topography is an amalgamation of caves, underground channels, and a rough and bumpy ground surface." It is created by the interaction of limestone with underground water; the water dissolves the soluble limestone to carve out underground channels and caves that are susceptible to collapse. A sinkhole may be created as a result of the collapsing of such structures from the surface. An example of a sinkhole in Tallahassee is Falls Chase.

"The Floridan aquifer is one of the most productive aquifers in the world." It spans about 100,000 miles underground through Alabama, Georgia, South Carolina, and all of Florida. It provides water for several large cities and numerous smaller communities and is intensely pumped for agricultural and industrial purposes. The Floridan aquifer is widespread and thick with rocks varying in permeability. It is because of this aquifer that Karst topography exists in Florida.

2) Water Quality
The water quality at Piney Z lake must be within acceptable parameters for the maintaining of it as an urban fishery. Such parameters that should be considered are temperature, dissolved oxygen, pH, turbidity, phosphates, and nitrates. All play a vital role in the survival of the lake and its inhabitants.

Temperature is important because freshwater fish can only tolerate certain fluctuations. Disrupting natural temperature fluctuations would disrupt aquatic ecosystems. Though good temperatures are dependent on the lake itself, most fish can tolerate between 68 and 89 degrees farenheit. Higher temperature reduces the amount of dissolved oxygen in the water. Temperature regulation must be maintained in order for fish to survive as well as reproduce. Ideal temperatures must be kept to insure the future of the lake's living organisms.

Dissolved oxygen measures the amount of gaseous oxygen dissolved in an aqueous solution. It is what fish breathe and "gets into water by diffusion from the surrounding air, aeration, and as a waste product of photosynthesis." An adequate supply of dissolved oxygen is needed for good water quality. It should not exceed 110% as it could cause "gas bubble disease," but not too low as to put stress on the fish which could lead to death.

pH is measure of the acidic or basic nature of a solution. It is important to water quality because a pH range of between 6.0 and 9.0 offers the most protection for freshwater fish and other aquatic organisms. pH is also important because it determines the toxic effects of aluminum, iron, ammonia, mercury, and other elements from agricultural, industrial, and domestic runoff.

Turbidity is the clearness of the water; it measures the amount of total suspended solids in the water. This is vital to water quality because the murkier (the higher the turbidity) the water is, the less able the sun is to penetrate through it, thus lessening the ability of plants to perform photosynthesis. Higher levels of turbidity can also clog or damage sensitive gill structure, decrease resistance to disease, hinder feeding activities and proper egg and larvae development.

Phosphates are important because they are necessary for the growth of plants and animals. They stimulate the growth of aquatic plants and plankton that fish feed on. Its effects can increase fish populations and improve the overall water quality. Phosphate levels should be monitored as too high levels can cause eutrophication.

Last, but not least, nitrates act as nutrients in the water. They are important because they limit supplies of oxygen in the water. Bacteria in the water quickly convert nitrates.