About Rob Grafton Expertise I can offer help up to UK degree level and have access to the national oceanographic library in Southampton. My speciality areas are marine biology ecology and physiology although I have a good understanding of chemical oceanography and physical Oceanography.
Experience I studied and am continuing my studies of M MarBiol at the university of Southampton
Organizations University of Southampton (uk)
National Oceanography Centre Southampton (uk)
JMBUK member
Expert: Rob Grafton Date: 10/23/2007 Subject: Carbon Dioxide levels in water
Question Why is there less Carbon Dioxide available to plants for photosynthesis if they
are submerged in water for a majority of the time?
Answer I don't quite know what level you are aiming this at so i apologize if some bits seem undermining and others a bit OTT.
There is more Carbon Dioxide (CO2) in the air than there is in the water. The CO2 Present in water is dissolved either from the air (by action of diffusion gradients) or produced by organisms and processes in the water.
Plants use up CO2 when photosynthesising, the rate of diffusion (CO2 being dissolved from the air) is very slow and even when the rate and amount of respiration by other organisms, (don't forget microscopic organisms can have a large effect in big enough concentrations), photosynthesis uses up more CO2 than there is CO2 produced by other organisms (and the plant in the dark). Photosynthesis is chemically (and pratically) 6 times faster than respiration (6 times more CO2 is used up during photosynthesis than in the same time respiration produces CO2) so overall CO2 is removed from the water by plants.
