Phenotypic diversity and ecosystem functioning in changing environments: A theoretical framework

Abstract

Biodiversity plays a vital role for ecosystem functioning in a changing environment. Yet theoretical approaches that incorporate diversity into classical ecosystem theory do not provide a general dynamic theory based on mechanistic principles. In this paper, we suggest that approaches developed for quantitative genetics can be extended to ecosystem functioning by modeling the means and variances of phenotypes within a group of species. We present a framework that suggests that phenotypic variance within functional groups is linearly related to their ability to respond to environmental changes. As a result, the long-term productivity for a group of species with high phenotypic variance may be higher than for the best single species, even though high phenotypic variance decreases productivity in the short term, because suboptimal species are present. In addition, we find that in the case of accelerating environmental change, species succession in a changing environment may become discontinuous. Our work suggests that this phenomenon is related to diversity as well as to the environmental disturbance regime, both of which are affected by anthropogenic activities. By introducing new techniques for modeling the aggregate behavior of groups of species, the present approach may provide a new avenue for ecosystem analysis.

Secreted enzymatic activities of ectomycorrhizal fungi as a case study of functional diversity and functional redundancy

“…Response diversity has been defined in Ecology as the diversity of responses to environmental change among species contributing to the same ecosystem function (Elmqvist et al 2003). It has also been proposed that the diversity of response to disturbance is critical to ecosystem resilience (Chapin et al 1997;Norberg et al 2001). In this context, such ecological concepts can be applied to ECMf communities to explore The number of occurrences of each species in each of the ten clusters is reported.…”

Cross–scale ecological dynamics and microbial size spectra in marine ecosystems

“…We note that for prokaryotic microbes, in general, species distinctions are imprecise and, in any event, a species-based approach necessarily ignores intraspeci c variations (e.g. Norberg et al 2001). By contrast, a continuum approach that accounts for features within a functional group has been speculated to allow for better understanding of group behaviour (Fisher 1958;Levin 1999), and the same assumption has recently been used to derive equations that describe the aggregate properties of a group of species in changing environments (Norberg et al 2001).…”

Habitat Destruction, Environmental Catastrophes, and Metapopulation Extinction

“…This approach has been successfully used over the past decades to face many ecological problems, ranging from host-parasite dynamics (Anderson and May, 1978) to biodiversity and ecosystem functioning (Norberg et al, 2001). The idea, better detailed hereafter, is that of deriving from (1) the equations for the dynamics of the first few central moments of the distribution of the p i 's.…”