Abstract: Using planar optode technology, we prepared fluorescence sensing membrane of pH, dissolved oxygen (DO) and partial presure of CO₂ (p_CO2), constructed 3 kinds of membrane in the simulated water/sediment system, and studied the twodimensional distributions and coordinated variation of pH, DO and p_CO2 in the system of the disturbance of the tubificid. The results show that there are hardly any changes in the parameters of overlying water and sediment system without the presence of bioturbation. On the contrary, there is obvious and coordinated variation in various parameters of system
of the disturbance of the tubificid with time. The pH,DO and p_CO2 in the system tend to be uniform with the extension of the disturbance time. There exists a certain coordinated variation tendency and interactions among three environmental parameters in the system with the presence of bioturbation.

Key words: planar optode, tubificid, water/sediment, bioturbation, dissolved oxygen