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
