Bioconstruction and biodiversity: their mutual influence

Abstract

SUMMARY: This paper describes the functional role of main benthic constructor organisms and reviews processes by which bioconstructions increase diversity and abundance of associated biota, and the reverse. Based on the literature, patterns of diversity of carbonate bryozoan bioconstructions, one of the most important groups performing important constructional roles, have been analysed. Diversity of bryozoan bioconstructors seems not to follow the latitudinal gradient, from tropics to increasing distance from tropics, recognised for coral bioconstructors. The only case of a "high diversity bryozoan reef" (Joulters Cays, Bahamas) represents a situation virtually unique in carbonate environments. Dimension and extension of bryozoan bioconstructions show their maximum in temperate environments, where seasonality or variability of environmental parameters could afford advantages for success to bryozoans. With only one exception (the bryozoan-serpulid build-ups from South Australia), diversity of biota associated with bryozoan bioconstructions is high, but comparison is not possible due to the fact that exhaustive faunal studies are rare, sometimes referring only to one taxon, and environments differing in depth range, salinity, hydrodynamics, trophic diversity, etc. are involved.Key words: biodiversity, biological habitat provision, bioconstructor, physical habitat structure, associated fauna, Bryozoa. RESUMEN: BIOCONSTRUCCIÓN Y BIODIVERSIDAD: SU INFLUENCIA MUTUA. -Se describe el papel funcional de los principales organismos bentónicos constructores y se revisan los procesos por los que las bioconstrucciones aumentan la diversidad y la abundancia de la biota asociada, y al revés. Sobre la base de la bibliografía, se han analizado los patrones de diversidad de las bioconstrucciones carbonatadas de los briozoos, uno de los grupos más importantes por su papel constructor. La diversidad de los briozoos en tanto que bioconstructores no parece seguir el gradiente latitudinal, desde los trópicos hasta distancias crecientes de éstos, que se ha reconocido para los bioconstructores que son los corales. El único caso de "arrecife de briozoos de gran diversidad" (los cayos Joulters, Bahamas), representan una situación prácticamente única en ambientes carbonatados. La dimensión y la extensión de las bioconstrucciones de briozoos presentan su máximo en ambientes templados, en los que la estacionalidad o la variabilidad de los parámetros ambientales pueden proporcionar ventajas para el éxito de los briozoos. Con una sola excepción (los edificios de briozoos y serpúlidos de Australia del Sur), la diversidad de la biota asociada con las bioconstrucciones de briozoos es elevada, pero no es posible la comparación debido al hecho de que los estudios faunísticos exhaustivos son raros, a veces se refieren únicamente a un táxon, y a que se trata de ambientes que difieren en rango batimétrico, salinidad, hidrodinamismo, diversidad trófica, etc.Palabras clave: biodiversidad, provisión de hábitat biológico, bioconstructores, estructura físic...

Extreme Phenotypic Plasticity in Metabolic Physiology of Antarctic Demosponges

“…Approximately 400 sponge species have been identified from the Southern Ocean (Janussen and Downey, 2014), where they can be dominant components of Antarctic shelf communities (Dayton et al, 1970(Dayton et al, , 1974Voss, 1988;Barthel, 1995). Their high biomass and morphological diversity are believed to be important in maintaining and structuring Antarctic benthic diversity (Gutt and Schickan, 1998;Cocito, 2004;McClintock et al, 2005). The efficient filter feeding of sponges makes them important components of the nutrient cycles of many marine ecosystems (Diaz and Ward, 1997;Diaz and Rutzler, 2001), as they perform an important role in benthopelagic coupling, transferring energy, and carbon from pelagic to benthic ecosystems (Gatti, 2002).…”

Coralligenous habitat: patterns of vertical distribution of macroalgal assemblages

“…Further studies considering different kinds of disturbance are necessary in order to test the model that environmental conditions can modify vertical patterns of distribution of coralligenous assemblages. Moreover, sessile animals, which in the present study were not considered, are determinant for the structure and functioning of these systems (Cocito et al, 2002;Cocito, 2004) and they may be an interesting topic for further research. …”

Spatial assessment of artisanal fisheries and their potential impact on the seabed: the Cap de Creus regional case study (northwestern Mediterranean Sea)

“…On the continental shelf and the canyon head, the emerging sessile organisms, such as cold-water corals, Pennatulacea, Ceriantharia, gorgonians, sponge gardens and calcareous algae are among the most sensitive species to fishing gear impacts since they all function as key benthic engineer organisms (Cocito 2004). Under this definition, large, erect well-skeletonised mound or branching organisms are considered to host abundant epifauna, providing a fundamental structural framework for the ecosystem (Kaiser et al 2002, Cocito 2004. To maintain the functional role of bioengineers, it is necessary to conserve dense assemblages (Thrush et al 1998, Kaiser et al 2002.…”