High-Resolution Field Measurements in Clam Pens

July, 2002 - The Marine Resources Research Institute in Charleston, South Carolina, is measuring the flows of water in clam pens, and in the aisles between the pens, using a SonTek/YSI field ADV.

The ADV is used to make high-frequency readings not only of horizontal current velocities, but also the degree of vertical mixing.

Measurements from the ADV were taken at up to 13 sampling heights above the bottom to characterize the benthic boundary layer conditions, and results indicate a relatively constant direction of vertical flow.

When results were compared with a control location (far away from the clam pens), it was discovered that the vertical velocity was reduced by half in the aisles between the pens, and by 90 percent within the pens themselves. This is a major consideration as the pens will significantly reduce the total food particle flux to the clams, and consequently, their growth.

• ADV Field