Piney Z Lake

Alicia B.



Physical Characteristics and History of Lake Piney Z
The Piney-Z site, which gets its name from an abundance of pine trees and z-shaped land configuration, is located east of Tallahassee about a mile off Apalachee Parkway. The property was purchased by the city in 1995 and includes the 193-acre Piney-Z Lake and 407-acres of surrounding property. Previously the lake was privately owned. It is surrounded by full, lush Florida vegetation. This includes pines, live oaks, mulberries, and other such plants. Animals found around this area include banded waters snakes, alligators, Bluegill and other species of commonly found fish. There is also a variety of birds. There is also an abundance of Indian mounds in which are buried ancient Indian artifacts.

An Indian mound found near Lake Piney Z

Examples of vegetation near Lake Piney Z

Piney-Z Lake originally started out as a river flowing through the beautiful wooded outskirts of Tallahassee, but during the 1930s it was dammed up for recreational hunting and fishing. When the lake was created it stopped the flow of water and caused the algae to begin a cycle of growth and decay which had a great impact on the ecosystem. This cycle formed a layer of dead algae on the bottom of the lake. The dead, decaying algae produced an abundance of carbon dioxide and created an imbalance of the ratio of oxygen to carbon dioxide in the water, reducing the amount of dissolved oxygen which is essential for the survival of many aquatic species. Around 1947 the muck was formed into finger dikes, but the muck continued to form. Until the lake was purchased by the city of Tallahassee in 1995, these problems went unnoticed for decades. The city proposed to drain the lake and scrape up the layer of muck out of the lake, to improve its water quality. After the water quality begins to improve the city will build a park around Piney Z lake and install trails for public use.

Eutrophication

Eutrophication is a condition in an aquatic ecosystem where high nutrient concentrations stimulate blooms of algae (e.g., phytoplankton).

Problems with Eutrophicaiton: Although eutrophication is a natural process in the aging of lakes and some estuaries, human activities can greatly accelerate eutrophication by increasing the rate at which nutrients and organic substances enter aquatic ecosystems from their surrounding watersheds. Agricultural runoff, urban runoff, leaking septic systems, sewage discharges, eroded streambanks, and similar sources can increase the flow of nutrients and organic substances into aquatic systems. These substances can overstimulate the growth of algae, creating conditions that interfere with the recreational use of lakes and estuaries, and the health and diversity of indigenous fish, plant, and animal populations.

Algal blooms hurt the system in two ways. First, they cloud the water and block sunlight, causing underwater grasses to die. Because these grasses provide food and shelter for aquatic creatures (such as the blue crab and summer flounder), spawning and nursery habitat is destroyed and waterfowl have less to eat when grasses die off. Second, when the algae die and decompose, oxygen is used up. Dissolved oxygen in the water is essential to most organisms living in the water, such as fish and crabs. Increased eutrophication from nutrient enrichment due to human activities is one of the leading problems facing some estuaries in the mid-Atlantic.

Testing for dissolved oxygen

Sinkholes and Karst Topography

Limestone, with its high calcium carbonate content, is easily dissolved in the acids produced by organic materials. About 10% of the earth's land (and 15% of the U.S.A.) surface consists of soluble limestone, which can be easily dissolved by the weak solution of carbonic acid found in underground water.
When limestone interacts with underground water, the water dissolves the limestone to form karst topography - an amalgamation of caves, underground channels, and a rough and bumpy ground surface. Karst topography is named for the Kras plateau region of eastern Italy and western Slovenia (Kras is Karst in German for "barren land").
The underground water of karst topography carves our impressive channels and caves that are susceptible to collapse from the surface. When enough limestone is eroded from underground, a sinkhole (also called a doline) may develop. Sinkholes are depressions that form when a portion of the lithosphere below is eroded away.
Sinkholes can range in size from a few feet or meters to over 100 meters (300 feet) deep. They've been known to "swallow" cars, homes, businesses, and other structures. Sinkholes are common in Florida where they're often caused by the loss of groundwater from pumping.
A sinkhole can even collapse through the roof of an underground cavern and form what's known as a collapse sinkhole, which can become a portal into a deep underground cavern.
While there are caverns located around the world, not all have been explored. Many still elude spelunkers as there is no opening to the cave from the earth's surface.

The Floridan Aquifer

The Floridan aquifer system is very important to a large number of people, despite general lack of knowledge of or about it. The Floridan aquifer underlies all of Florida, South Georgia, and parts of both Alabama and South Carolina.' This particular aquifer system is one of the major sources of ground-water in the United States. For this reason and more, studies of its function have been done for years. Each and every day more than 3 billion gallons of water are issued up from the Floridan aquifer. These 3 billion gallons of water represents less than 30 percent of the actual flow through the Floridan. The aquifer consists of a large area of connected carbonate rocks that range in age from late Paleocene to Early Miocene. It covers a total area of about 100,000 square miles. The connective tissue of these very porous rocks is the water that is the Floridan aquifer's life force.

The rocks that make up the aquifer are also responsible for dividing it into an Upper and Lower aquifer. The two are separated by a section of low porosity, which causes the water to run much slower. The two sections of the aquifer are defined solely by the permeability and not a geographic boundary of any kind. The definition does not imply that there is a rock or time stratification that makes the two areas different.

The flow system of the aquifer has been interrupted by two different things: man's activities such as pumpage, impoundments, and dredging as well as deviation from normal amounts of rainfall. The disruption of the aquifer's flow could begin at almost any point on its path. The aquifer's water originates in the larger bodies of water of the Appalachian region; it flows downstream until it is forced underground. The aquifer flows from the higher altitudes of North Georgia and South Carolina to the flatter area which is Florida.

The aquifer is a source of more than just water for those who utilize it. The aquifer produces water that contains a large amount of minerals. The minerals that are supplied by the aquifer are calcium, magnesium, small amounts of iron, etc. While many people take in these vitamins and minerals as a part of their diets, it is also useful to know that the water that they drink is rich in the minerals that are required by the body.

Water Quality Tests

Dissolved Oxygen (DO) - Dissolved oxygen is a measure of the amount of oxygen freely available in water. It is commonly expressed as a concentration in terms of milligrams per liter (mg/L) or ppm, or as a percent saturation, which is temperature dependent. Percent saturation is the percent of the potential capacity of the water to hold oxygen that is present. DO levels below 1 ppm will not support fish; levels of 5 to 6 ppm are usually required for most fish. We tested the DO by using dissolved oxygen testing kits which incorporated adding chemicals to the sample that would indicate the amount of DO in the water sample.



DO testing using kits

pH- pH is a general measure of the acidity or alkalinity of a water sample. The symbol pH stands for potential for hydrogen. The pH of water, on a scale of 0 to 14, is a measure of the hydrogen ion concentration. Water is considered basic with a pH greater than 7 and water is considered acidic with a pH less than 7. The pH of a stream affects the organisms living there as you can see from the scale below. We tested the pH with ed technological instruments which could measure the pH of the water with a probe.



Turbidity- Turbidity is the measurement of lack of water clarity. Turbidity is the result of suspended solids in the water. Suspended solids are variable, ranging from clay, silt, and plankton, to industrial wastes and sewage. High turbidity water will appear to be murky or muddy. We observed the turbidity of the water everyday we ran tests, by recording whether the water was murky or relatively clear. High turbidity will reduce the amount of sunlight able to penetrate the surface of the water, and interfere with the natural role that is played by sunlight in the aquatic ecosystem.



An example of high turbidity

Nitrates- Nitrogen is a much more abundant element in nature than phosphorus. Nitrogen is known to be an important plant nutrient, thus it is used often as a fertilizer and is found in high concentrations in agricultural runoff. Nitrate concentrations result from improperly functioning septic systems. Too much nitrogen contributes to eutrophication of lakes and streams, reducing the ability of the water to support life.


Total Phosphorus
- Phosphorus is usually present in river water as phosphates, and is in very small amounts unless there has been human caused enrichment of the water. The natural scarcity of phosphorus can be explained by its attraction to organic matter in soil particles. Generally the lower the total phosphorus value in the water, the better. Phosphorus is considered to be a limiting factor in aquatic systems, meaning that it is not freely available for easy consumption by aquatic organisms. The amount of phosphates that water can hold without polluting it varies. In a river draining into a natural lake, the phosphate level should not exceed .05 mg/L. Natural lake level phosphates should not exceed .025 mg/L. Phosphorus is the major contributing factor in the process of euthrophication. Inputs of phosphorus come from erosion, fertilizers, detergents, and the draining of wetlands. A higher amount of phosphates means a less chance of survival for aquatic species.

Temperature- Measure of the average kinetic energy. The water temperature is very important. If the temperature is too low or too high it could kill the fish and lessen the chances of successful reproduction. We found the temperature by using a thermometer, and recording the observed degree (Celsius).

I got most of my information from these sites: http://www.lincoln.leon.k12.fl.us/media/menu/Piney_Z_Project.html http://www.epa.gov/maia/html/eutroph.html http://www.valdosta.edu/~tmanning/hon399/sandra.htm http://imc.lisd.k12.mi.us http://geography.about.com/library/weekly/aa060800a.html http://floridaconservation.org/fishing/news-rel/nrw-pine.html

Copyright © 2010 The Florida Geographic Alliance