デジタルフォースゲージを用いた新潟県沿岸域における海底泥の硬度測定結果について

抄録

In this study, I discuss a method to measure the bottom material hardness using a digital force gauge. I conducted the field observations of the bottom material hardness along the Niigata coast. Values of the penetration resistance of the force gauge per 5cm depth into the bottom material ranged 0.81-5.72 N. The penetration resistance was higher than l.4 N in sandy mud bottoms. Muddy bottoms were classified into soft (< 1.4 N) and hard (1.4 -3.0 N) categories. The density of the benthic fauna in muddy bottoms was lower for hard categories than for soft ones. These results suggest that the hardness of the bottom material is one of the important factors of the bottom environment which affect the benthic fauna.