In this experiment, the independent variable was the location and type of the water sources and the amount of urbanization in the area. The water sources were both salt and fresh water, and were in both rural and urban areas. The first water source was
The dependent variable was the amount of plankton found in each sample. The plankton was counted and identified. Plankton are tiny organisms made up of plants and animals that cannot swim freely. The word plankton comes from the Greek word planktos which means wandering or drifting. Plankton is the most abundant source of life except for bacteria. They are at the bottom of the food chain and support many animals (Australian museum, 2002). Plankton is the base of the food chain and the food web. They support many fish in the ocean mostly during their larvae phases. Some fish continue to eat plankton all their life. Plankton are great indicators of environmental and aquatic health because of their short life and high sensitivity to environmental change (Chesapeake Bay Program, 2004).
Phytoplankton is the plant like plankton that float at or near the surface. They are single-celled and mostly round organisms. To get energy, the phytoplankton do photosynthesize (New Hampshire Public Television, 2008). The phytoplankton are the primary producers of food and oxygen in the ocean. The most common types of phytoplankton are diatoms, golden brown algae, green algae, blue green algae, dinoflagellates, microflagellates, and cryptomonades (Chesapeake Bay Program, 2004). Diatoms are long and thin plankton that link together in long chains, and they are single-celled algae. Dinoflagellates have two flagella and they come in all shapes and sizes. Some of the dinoflagellates have shells, but not all of them photosynthesize. A form of brown algae is phaeophyta and cyanobacteria. Some cyanobacteria use nitrogen for energy rather than photosynthesis (New Hampshire Public Television, 2008). Too much phytoplankton can affect water quality because they can reproduce fast under the right conditions. The rapidly reproduce when the water temperatures rise and there are excess amounts of nutrients (Chesapeake Bay Program, 2004).
Zooplankton are the animal like plankton that move with the ocean currents. Zooplankton vary in size from tiny microbes to jellyfish (New Hampshire Public Television, 2008). Some Zooplankton are single-celled and are primary and secondary consumers. They can also feed on bacteria and other plant material (Chesapeake Bay Program, 2004). Two types of phytoplankton are holoplankton (permanent plankton) and meroplankton (temporary plankton). If meroplankton survive they will become nekton or free-swimming organisms such as fish, crustaceans, and other small marine animals. The most common type of zooplankton are the copepods. They are called the insects of the sea because there are over 10,000 species, and they can be found in salt and freshwater. They are very small forms of crustaceans, and they can eat phytoplankton and other zooplankton. They are the largest source of protein in the ocean. Krill are the smallest animals in the ocean and they are the food for the largest animals in the ocean. There are over 82 species of krill, and they have bioluminescent organs so they can be found in the sunlit zone or twilight zone (New Hampshire Public Television, 2008). Zooplankton are also good indicators of environmental conditions because they are sensitive to the changes in water quality (Chesapeake Bay Program, 2004).
A plankton net was used to catch the plankton. The mesh on plankton nets are smaller than normal nets because the plankton are so small. Phytoplankton nets have 36/1000 mm mesh openings, and zooplankton have 1/3 to ½ mm mesh openings (Classroom Bats, 2004). Microplankton are mostly diatoms and dinoflagellates that range in size from 20-200 µm. Nanoplankton are mainly coccolithophorids and silicoflagellates that are about 2-20µm. Picoplankton are mostly cyanobacteria and are 0.2-2µm. most plankton are found in dilute concentrations so when catching the plankton it is helpful to have a large volume of water. The net will turn a golden brown when there is a good amount of plankton in it (Monterey Bay Aquarium Research Institute, 2001).
The water samples in this experiment were tested for multiple tests and compared for a water quality index. The water quality index calculator was used to determine the water quality of each water sample. The calculator asked for the measurements of each test for each water sample and it compared it to a scale from excellent to poor (Oram, 2007). A water quality index is the chemical, physical, and biological characteristics of water. The vulnerability of the water depends on the natural landscape features, climate and atmospheric contributions, and human activities. Microorganism, bacteria, and chemical pollutants can be found in the water and endanger the life of the aquatic and terrestrial animals. Sewage spills and pesticides can leak into the water along with runoff coming from the roads and parking lots. Farms can also pollute the water by adding more fertilizers, manure, nitrogen, and phosphorous to the water. Water quality has become a major problem in the world because of the rapid growth of the population and urbanization (Perlman, 2001). The majority of the
There were a total of six tests for water quality and the data obtained was put into the water quality calculator. This determined the water quality of the water. These tests must be done in order to determine the water quality. The first water quality test was the test for dissolved oxygen. The dissolved oxygen test measures the water’s ability to support animal and plant life. The second test was for turbidity to measure the water’s clarity, which allows the sunlight to reach the lower depths. The main sources of turbidity are erosion, living organisms, and human activities. The pH test was used to determine the pH of the water because if the pH is below 4 and above 9 then nothing can live in the water. The temperature test was done in two spots, and if the difference was greater than 2 degrees Celsius then there is thermal pollution. The nitrogen in the water is necessary for plant and animal life, and the water is tested to control the amount of eutrophication (Gada, 1997). Eutrophication is a process where the water sources receive excess nutrients that stimulate excessive growth. The excess plant growth is also called algal bloom, and this reduces the dissolved oxygen levels in the water. Once the levels of oxygen have lowered no life can be supported and everything dies (Cloern, 2001). Phosphates are nutrients required for growth so a phosphate test was done to see if there were enough nutrients available for growth to occur (Gada, 1997).
This project will be limited to the some lakes, rivers, and the Atlantic Ocean in