The Causes and Solution Methods of Isoyake (Rocky-Shore Denudation)

Abstract

Rapid disappearance of useful seaweeds and seagrasses in the coastal area of Japan is called isoyake, i. e., rocky-shore denudation. Feeding damage by plant eating fishes and sea urchins is considered to be the main cause of the isoyake. A recent increase in the feeding damage is closely related to sea water temperature rise due to global warming. As the seaweeds and seagrasses can absorb and fix great amount of CO₂ through photosynthesis, the so-called blue carbon is significantly decreased by the isoyake and, hence, the global warming is further accelerated. The current situation and some solution methods of the isoyake are briefly reviewed in this article.