<；P>；PROBLEM TO BE SOLVED: To selectively suppress adhesion/proliferation of sargasso and promote adhesion/proliferation of sea tangles on a block consisting of carbonated/solidified body for undersea installation. <；P>；SOLUTION: The block for undersea installation comprises a carbonated solidified product obtained by solidifying a fine-grained non-carbonated Ca containing material through a carbonation reaction, wherein the block has convexoconcave parts at least on the top, and the parts have cross-sectional shape having continuous peaks and valleys and the inclination angle of the peaks is at least 30 degree and the depth of the valleys is at least 5 mm. The adhesion/proliferation is selectively suppressed by colonization in a state in which eggs of sargasso can not adhere by using the convexoconcave parts. <；P>；COPYRIGHT: (C)2010,JPO&INPIT
