Abstract
A simple coring device was designed for obtaining surface sediments and the overlying, near-sediment-surface water in lakes and shallow marine bays. It consists of a removable corer tube and valve attached to the inside wall of an Ekman grab by a clamp. The device has several advantages as follows: 1) core samples can be obtained with minimal disturbance to the sediment-water interface; 2) samples can be successfully collected even from sandy bottoms; 3) it can be easily operated even from a small boat.