Results

Observations:
      1. The C4 plants show the expected increase in growth in the warm temperature.
      2. It must be noted that the sunflower that was selected for measurement did not grow very much, but another plant in the same pot grew well in the warm CO2 which makes the graph seem to indicate that C3 plants in general would not do well in warm CO2-enhanced environment.
Picture:
Corn in warm temperature on the left.
Corn in cold temperature on the right.

The increased CO2 is on the left side. 
Noticeable difference in size with the warm temperature plants
  • Observations:
    1. This graph shows results that were puzzling, as the "cool" side has the greatest amounts of Oxygen, meaning that the rate of photosynthesis was higher.
    2. In both  the warm and cool environments, the increased CO2 may have been responsible for the higher rate of photosynthesis.

     
    Observations:
    1. Higher pH indicates higher rates of photosynthesis
    2. Comparing just the two warm aquaria, the increased CO2appears to increase photosynthetic rate, but results are mixed in the cool aquaria.

     
    Observations: 
    1. The C4 plant seems to do better in the Warm, CO2-enhanced  environment.
    2. The Barley, which is most like the Corn in structure, but has C3 metabolism, shows little effect  from change of temperature or CO2.
    3. The C3  dicot outgrows the C4 monocot in the cooler temperature, as long as there is a high level of CO2 .
    4. At warm temperatures, the C4 plant has the advantage.

     

    Conclusion


    Our data indicates that C3 plants in general did  not do  as well in warm,  CO2 -enhanced environment as the C4 plants. The C3 plants did as expected, growing well in the cooler environment with CO2 enhancement.

    If these results were extrapolated to world-wide models, it would be predicted that rising CO2 levels would give a competitive advantage to C4 plants.  Further experiments with C3 and C4 plants growing in separate environments are needed to indicate what the influence of these plants are on the atmosphere.
     

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