PROBLEM TO BE SOLVED: To provide a porous concrete body constituted so as to realize a structure suitable for growing algae at a low cost using a waste material such as slag or the like and capable of accelerating the adhesion growth of algae to restore a submarine forest. SOLUTION: Blast furnace slow cooling slag is used as coarse aggregate becoming the principal part of concrete or copper slag is used as regenerated aggregate and fine aggregate to form the porous concrete body in a porous state with a predetermined void ratio. Bamboo materials having through-holes formed by processing the nodal parts of a bamboo are arranged so as to be embedded in concrete in a piercing state to provide a large number of voids and through-holes in a state arranged in the sea. Cost reduction is realized using slag being a waste material as aggregate and metal components essential to organisms are dissolved in seawater to accelerate the addition and growth of algae on the surface of the porous concrete body. Further, the inhabitation of small fishes and shellfishes is assisted by the through-holes in the bamboo material, and algae and fishes and shellfishers living in an ecosystem in a mutually related state are fixed at the same time not only to establish a state nearer to nature but also to restore the submarine forest. COPYRIGHT: (C)2005,JPO&NCIPI
