Living in the canopy of the animal forest: Physical and biogeochemical aspects

Abstract

Long-lived hard and soft coral species that are able to develop dense patches with a complex, three-dimensional structure form an animal forest canopy, similar to trees in terrestrial systems. Aside from the shelter provided by this canopy to other organisms, the animal forest can significantly modify the local physical and biogeochemical environment. In the first part of this chapter, the modification of benthic boundary layer hydrodynamics in and above canopies is described, with a focus on the impacts of canopy density and flexibility. In the second part of this chapter, the structure of diffusive and advective mass transfer in canopies will be presented and discussed in relation to the biogeochemical transformations observed in animal forest canopies. Ongoing challenges in the conceptualization of physical and biogeochemical processes in animal forest canopies are also exposed. In the third part of this chapter, we review the factors that form the basis of a mechanistic explanation of the development of micro-niches, which explain the large diversity hosted in animal forest canopies.