The carbon isotopic composition of marine kerogen is thought to be primarily controlled by COz availability. And yet almost no experimental data exists on the effects of different COz levels on carbon isotopic fractionation. Funds are provided for a two years' study to examine the effects of increased pCOz levels on the Fractionation of carbon isotopes of phytoplankton during phytosynthesis using marine mesocosm system at URI Marine Ecosystem Research lab. Experiment will employ 4 mesocosm tanks for up to 16 months. Each tank will be held at differing but constant TCOz, pCOz, and pH levels. Weekly estimates of productivity will be made and temperature, salinity , nutrients, etx. will be monitored to learn about the phytoplanktonic response of carbon isotopic franctionation to increased pCOz level.
