IMBIV   05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
capítulos de libros
Título:
Functional biodiversity at the crossroads between responses to the environment and ecosystem functioning
Autor/es:
DÍAZ, S; LAVOREL, S; CHAPIN, FS; TECCO, PA; GURVICH, DE; GRIGULIS, K
Libro:
Terrestrial Ecosystems in a Changing Environment
Editorial:
Springer-Verlag
Referencias:
Lugar: New York; Año: 2007; p. 81 - 91
Resumen:
Functional diversity (FD) comprises the kind, range, and relative abundance of functional traits present in a given community. Major global change drivers, including changes in climate, atmospheric composition, land-use/ disturbance regime, and biotic exchanges, affect and are affected by FD in a non-random, and often predictable way. There is overwhelming evidence that the kind of traits that are present in higher abundance are major drivers of shortterm ecosystem processes and their feedbacks onto global change drivers. Both the response of plant traits to environmental filters and their effects on biogeochemical and biophysical ecosystem processes (including simple, direct interactions with herbivores and decomposers) can be predicted with acceptable accuracy, although present theory cannot account for the mutually-neutralizing or synergistic effects of combinations of traits. The role of the range of traits in influencing ecosystem functioning by resource use complementarity and facilitation is less clear, and fewer empirical examples are available, although both theory and some experimental evidence suggest that the role of subordinate species is important in maintaining long-term stability. Finally, there are other biodiversity-related effects, which are the result of indirect interactions, and/or interactions involving keystone species and/or ecosystem engineers, that cannot be predicted on the basis of the kind, range or relative abundance of traits, and remain a major challenge for the FD approach. Non-linearities that are triggered by changes in climate, land-use regime and/or biotic interactions that involve altered FD, and in turn affect global change drivers and ecosystem services, represent a major threat to the integrity of the life-support systems. There is therefore an urgent need for more theoretical and empirical studies that would lead to better understanding and anticipating their consequences. The quantification of functional diversity is not free from difficulties, and it is certainly less straightforward than counting the number of species, at least in areas with welldescribed floras. However, it provides a much stronger insight into the links between community structure, ecosystem functioning, and global change drivers and ecosystem functioning than does the consideration of species richness alone. Major venues for future research in FD are (1) the identification of those functional traits or functional trait combinations that are more likely to trigger ecosystem and landscape-level non-linearities; (2) continued efforts to measure functional traits under a wide range of biomes and regions, following standardized lists and protocols (see Lavorel et al. 2007, Chap. 13 of this volume); (3) more empirical investigation on how important are the roles of resource use complementarity and facilitation in determining ecosystem functioning under different degrees of environmental filtering; (4) more empirical and theoretical work on how FD effects on ecosystem processes translate into changes in global change drivers and ecosystem services; and (5) the design of easily-workable FD indices that could be applied to a wide range of natural situations, and thus broaden the possibilities of empirically testing the functional role of biodiversity.