1.5.1 Phytoplankton "See the Light"
Ask students what they remember about the oxygen cycle-most early elementary students are familiar with photosynthesis as the oxygen/carbon dioxide exchange between plants and animals. There are no trees in Antarctica. So, where's the oxygen coming from? Encourage speculation.
At the lowest end of the food web are phytoplankton, the "food" of tiny marine animals, particularly krill. Phytoplankton make their food through photosynthesis. Fueled by the energy of sunlight, they convert carbon dioxide and water into simple, sugary food. During photosynthesis, they release oxygen as a waste product. They also incorporate carbon dioxide.
Length of day and extent of sea-ice cover are both important environmental factors given the extreme seasonal cycles. Depending on the latitude, there may be enough light for the microscopic plants to grow in the winter; they only need about four hours of daylight. The amount of light that the plants receive depends on:
Create a phytoplankton culture in a hay infusion:
(NOTE: Sometimes the plants run out of nutrients in culture so students may have to add new hay to the infusion)
Go on-line to see Robin Ross' suggestions for how to add "grazers" to the environments, when North American spring permits. And also to find data to compare and contrast hours of daylight as winter becomes spring, and plot this with analogous records from Palmer Station.
Have students plot daylight hours on maps, comparing and contrasting results from various classes participating in LFA 2.
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