If you examine pond water without culturing it, you'll probably find the protozoa are somewhat difficult to find because they are not present at high density. To increase the protozoa density, make a hay infusion by putting the water in an open jar and adding cut dried grass or hay. The grass or hay should be green when it was cut and dried, and be free of herbicides and pesticides. You may also wish to add a few grains of yeast and a few drops of skim milk. The sugars in the dried grass or hay and the nutrition provided by the yeast and milk provide food for the bacteria in the water. If the jar is kept at room temperature for a few days the bacteria proliferate (and make quite a smell!). The bacteria are food for the protozoa, so the bacteria population boom will create a corresponding protozoan population boom.
Be careful to not add too much hay, grass, yeast, or milk. This will overfeed the bacteria and they'll poison the water with their waste products before the protozoan population gets a chance to catch up.
Protozoa are oxygen breathers. Give them oxygen by using a pipette to bubbling air into the water at least once a day.
Taking samples with a pipette near the surface of the water, near floating debris, and near the bottom of the jar will often give you different types of microzoa to examine. The hay infusion population will peak about a week after making it. If you want to keep it going, get more fresh water from the original source, add hay, etc., and inoculate the new culture with several pipettes filled from the old culture.
Remember that the hay infusion has a very high bacteria count. While the vast majority of bacteria are not harmful to humans, there may be bacteria in the culture that could cause infection on contact. Be sure to wash with soap and water if the culture gets on your skin. Rinse out your eye with lots of clean water if any of the culture liquid contacts it. If you get any of the water in a cut be sure to wash it out and sterilize it with hydrogen peroxide or iodine.
I. Introduction
A pond is characterized as being a small body of water that is shallow enough for sunlight to reach the bottom, permitting the growth of rooted plants at its deepest point. Seldom do ponds reach more that 3.6-4.5 meters (12 to 15 feet) in depth.
An undisturbed pond will age. Even though at first a pond will appear to be lifeless, a new pond will acquire both plants and animals by the different forms of inflowing water. Large deposits of rootless stoneworts and hornworts become established; microscopic plankton form drifting masses; water boatmen and winged whirligig beetles alight on the surface to swim. Plants colonize all of the zones and provide food and shelter to a wide variety of animals. Frogs begin to visit and lay eggs.
Ponds are considered to be part of the freshwater habitat-which are divided into flowing water and standing water. The flowing water habitat is divided into rapid and slow streams. The standing water habitat are divided into lakes, ponds, and swamps. Ponds can be even further divided into those with bare bottoms and those whose bottom contain vegetation.
Ponds are noted for their abundant and rich varieties of plant and animal life, which all are maintained in a delicate ecological balance. Life forms range from microscopic bacteria to insects, fish, small animals, and birds. As ponds age, the number of species living in it steadily increases until, finally, the growth of larger plants, algae, and the accumulation of wastes convert it into a marsh or cause it to dry up. This process is known as ecological succession.
The study of the relationships between living things and their environment is known as ecology. However, the curriculum, The Ecological Relationships That Exist Within A Pond Community actually covers a smaller division of ecology called limnology-the science that deals with the interrelationships of plant and animals in aquatic environments. Since the pond represents a stable environment where living things interact, and materials are used over and over again, it is considered an ecosystem.
Limnologists have identified five different types of ponds as follows:
(1) Cypress Ponds which are commonly found in the central or lower Mississippi Basin and along the coastal plain of the Southeastern United States. Their waters are described as being brownish in color, and many dry out during parts of the year. Willows, bay trees mixed with cypress trees, grows along the shore and are often found out in the waters.
(2) Bog Ponds are often found in the moist temperature regions of North America. The water is highly acidic and often muddy. Alders grow profusely on the shore and cedar trees dominate the high ground. Thick beds of sphagnum extend outward from the shore and floating-leaf plants usually cover the surface.
(3) Meadow-Stream Ponds form where streams widen and the speeds of its currents slow down tremendously. The shallow part of the pond usually has an abundance of pondweeds, cattails, stoneworts and other plants with emergent leaves. They also have plants with floating leaves on the surface of the water, such as lilies and water shields.
(4) Mountain Ponds, which are often formed by glaciers, are another type of pond. The bottoms of these ponds range from being rocky, graveled or muddy. Most of the time Mountain Ponds have ice in them and they usually dry up at some point during the summer. Sedges grow along its margins. In spite of the ponds short summer season, a variety of animals and plants live in these icy waters.
(5) Farm Ponds are man-made ponds built to help keep the farmlands fertile. Farm ponds are at least three feet deep at the shoreline in order to prevent plant growth that would lead to the early succession of the pond. It should also have a spillway to control the water level. Farm ponds usually become abundant in fish, and are usually good waters for swimming and boating. They should also fill from seepage, not from another stream which would fill the basin of the pond with silt and eventually kill the pond.