A Historical Perspective of the Brazilian Rhodolith Beds: Discovering a Hidden Ecosystem

This chapter discusses, from an historical perspective, the evolution of scientific knowledge since the description, by foreign naturalists, of the first types of rhodolith-forming species found in the Brazilian coast, in the late nineteenth century. During the second half of the twentieth century, geological and geophysical surveys demonstrated that calcareous algae beds along the Brazilian continental shelf possibly were the largest on the planet, which, consequently, attracted many commercial interests to the region. These commercial potential of rhodolith beds leveraged the first ecological studies on the Espirito Santo Continental Shelf, as a requirement for exploration activities. These studies revealed a remarkably diverse community, dominated by high brown algae biomass, attached to the relatively light rhodoliths, resulting in the constant displacement of the whole community, due to the wave action. A decrease of biomass was observed, probably related to the abrasion and burial during storms, resulting in a decrease from 2328 g.m−2 f.w. in December 1986 to 65 g.m−2 in May 1994. After the new millennium, new technical conditions allowed the increase of studies, but the knowledge is still incipient, with special concerns relying on their functional and economic roles. Besides, the population and managers, in great part, do not even know the existence of such an ecosystem, precluding support to conservation.