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Kathy G.

Natural and Cultural History of Piney Z/Lake Lafayette

Piney-Z is a part of many lakes in the Lake Lafayette chain and is in the process of restoration. It gets its name from pine trees found on an aerial map in the shape of a Z. It is located east of Tallahassee about a mile away from Apalachee Parkway, just down the road from Tom Brown Park. The land was purchased by Tallahassee in 1995 and includes the 193-acre Piney-Z Lake and also 407-acres of surrounding property. After the restoration of the lake, it will be knows as Piney-Z Fish Management Area, and the surrounding area will be open to the public for biking, picnicking, hiking and wildlife viewing. The city is also planning to build a bike/walking trail behind the back of Piney-Z that will join Piney-Z Lake Park and Tom Brown Park. This will provide the Piney-Z residents with convenient access to both parks. All residents will have lake access once the park opens. Piney-Z Lake belongs to the city of Tallahassee, and will be open to the public as a city park.

Piney Z is a big lake surrounded by trees. It has “fingers” that are used as a dock made out of land for the sport of fishing. It is made out of the material that they dredged out from the bottom of the lake to restore it. The picture below is the main physical features of the lake and the picture was taken during the process of the restoration, therefore you will notice that there are still things that need to be “mowed” out of the bottom of the lake.

The following picture is one of my group from Piney Z doing various experiments on a finger of Piney Z Lake.

As we know man has taken over the area of Piney Z, but we must realize that it was man that saved this lake from dying. If these people didn’t do all of this work then the lake wouldn’t have been there for everyone to enjoy. This does not mean that we should abuse it though, we should take care of this lake that our county saved from being gone.
Florida Karst Topography:

Tertiary Karst Topography

Example 1: Tertiary Karst Topography

Perched water system

Example 2: Perched water system

Marginal Region

Example 3: Marginal Region

Karst topography is defined as irregular topography, or the shape and physical features of a land, characterized by sink holes, streamless valleys, and streams that disappear underground. They are all developed by action of surface and underground water in soluble rock such as limestone. Florida is the best example for karst topography because of our abundant supply of limestone, which is a very soluble rock.

Eutrophication is the gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake like Piney Z. The productivity or fertility of such an ecosystem increases as the amount of organic material that can be broken down into nutrients increases; this material enters the ecosystem mainly through runoff that carries debris. Water blooms often develop on the surface, preventing the light penetration and oxygen absorption necessary for underwater life; this is a bad thing. Basically, eutrophication is when there are too many nutrients in the water. When human activities add nutrients to water, it is called cultural eutrophication, and theref-ore natural eutrophication is from the nature.

The Floridan aquifer is a large layer of porous rock hundreds of feet beneath most of Georgia's coastal plain and nearshore waters, as well as parts of Florida and South Carolina. An aquifer is not an underground cavern filled with sloshing water, but rather solid rock or sediment in which the spaces between grains of sand, silt or clay are completely filled with water. Groundwater is not stationary; it flows vertically and horizontally from areas of high potential energy to areas of low potential energy. Water enters the Floridan aquifer along the Fall Line and flows-over many years-down an energy gradient toward the coast. But it can also flow to or from other aquifers, and discharge or receive water from streams, lakes and wetlands. Most importantly, our actions can change the directions of these natural flows. And as groundwater flows into and out of other waterbodies, it carries with it dissolved minerals, nutrients or contaminants, sometimes having unanticipated or unintended consequences. Pumping huge amounts of water from the Floridan aquifer, for example, has begun to draw salt water from the ocean into the aquifer, which could render coastal Georgia's source of high quality drinking water useless.

Water Quality

The following are the water quality parameters that are important in Piney Z:

Change in temperature - For this test, water temperature is measured at the sampling site and a mile upstream from the site to determine the change in temperature. Most physical, biological and chemical processes in a river are directly affected by temperature. For example, temperature affects the amount of dissolved oxygen in water (cold water can hold more oxygen than warm water); The rate of photosynthesis by plants; The metabolic rate of aquatic animals; And the sensitivity of organisms to pollution, disease and parasites. Changes in water temperature may be the result of thermal pollution (adding warm water to a body of water), changes in the amount shade over the river, and soil erosion. Soil particles suspended in water absorb heat from sunlight. Temperature is important because cold water is better because it can hold more action, and temperature change will lead to explanations on why certain things may be happening.

Dissolved oxygen (DO) - Oxygen from the atmosphere is mixed in water by waves and tumbling water. Algae and rooted aquatic plants also put oxygen into water through photosynthesis. Most aquatic plants and animals must have some amount of oxygen to survive. This is important because only waters with consistently high levels of dissolved oxygen are considered to be stable ecosystems and able to support diverse populations of organisms. If the levels aren't high enough then the ecosystem won't survive.

pH - Water (H2O) is composed of OH- (hydroxyl) ions and H+ (hydrogen) ions. The pH test measures the concentration of H+ ions, and pH values range from 0-14. A pH value of 7 is considered neutral, less than 7 is acidic, and more than 7 is basic. Acidic water has more H+ ions than OH- ions, neutral water has equal numbers of H+ and –OH ions, and basic water has fewer H+ ions than –OH ions. The pH of natural water in the U.S. is usually between 6.5 and 8.5. Most organisms cannot live in water that has extremely high or low pH values (more than 9.6 or less than 4.5), therefore it is important to have the proper pH level. Things like acid rain, which is caused by nitrogen oxides and sulfur dioxides (primarily from automobile and coal-fired power plant emissions) that are converted to nitric acid and sulfuric acid in the atmosphere, are factors that will change the pH levels. These acids from the rain combine with water vapor in the atmosphere and return to land as acid rain or acid snow. This deposition may increase the acidity of a body of water, especially in freshwater systems that do not have a limestone buffer. Limestone neutralizes the effects of acid rain deposition.

Turbidity - Turbidity is a measure of water clarity. Murky water has a high turbidity, while clear water has a low turbidity. Suspended solids—such as soil particles, sewage, plankton and industrial wastes—in water increase turbidity and decrease the transmission of light. An increase in turbidity decreases biodiversity because more turbid waters are warmer and allow less sunlight through for photosynthsesis. Also, suspended solids harm aquatic organisms by clogging gills, increasing susceptibility to disease, slowing growth rates, and preventing the development of larvae and eggs. These factors will lead to a failure in the ecosystem and therefore has to be monitored for maintaining Piney Z.

Total phosphates - Phosphorus is a nutrient that plants need to grow. In most waters, phosphorus is present in very low concentrations, which limits plant growth. However, humans add phosphorus to water through human and industrial wastes, fertilizers, and disturbances to land and vegetation. When human activities add nutrients to water, it is called cultural eutrophication. Excess phosphorus stimulates plant growth and can cause algal blooms. When this vegetation decomposes, dissolved oxygen levels can drop dramatically, especially near the bottom of the body of water. If there are too many phosphates, as explained, then it can lead to many problems.

Nitrates - All plants and animals require nitrogen to build protein. It is much more abundant than phosphorus and is most commonly found as atmospheric nitrogen (N2). This form can't be used by most aquatic plants, however, and must be converted to ammonia (NH3) and nitrates (NO-3). In these forms, nitrogen acts as a plant nutrient and can cause eutrophication. Plants are less sensitive to changes in ammonia and nitrate levels than they are to phosphorus, however, because nitrogen rarely limits plant growth. Sources of nitrates added to rivers by humans include sewage, fertilizers, and runoff from dairies and barnyards. Once again, too many nitrates are bad for places like Piney Z.

We did measured the water quality parameters in many ways:

For the temperature, we had a graphing calculator hooked to a thermometer. We got the measurements of the temperature on the calculator and then recorded in into our book.

Dissolved oxygen, pH, turbidity, phosphates, and nitrates were measured through a special kit. We used all types of chemicals to get our results. First we would take water from the Piney Z Lake and then put it in a large beaker. We then got our water from here and put it through a multitude of testing. Through the use of the kits, with the little jars, we were able to find all the measurements possible to conduct our experiments.

Works Cited