Functional Diversity: An Important Measure of Ecosystem Functioning

Abstract

Functional diversity is a component of biodiversity that generally covers the range of functional traits of microorganisms prevailing in an ecosystem. Functional diversity is of high ecological importance because it is capable of influencing several aspects of ecosystem functioning like ecosystem dynamics, stability, nutrient availability, etc. Functional diversity of a community can be measured by functional richness and evenness. Functional richness refers to the number of species inhabiting a particular niche and functional evenness reveals how evenly the species are being distributed. Increase or decrease in functional richness and evenness simultaneously increases and decreases the functional diversity respectively. Decrease in functional richness and evenness decreases the ecosystem productivity and stability which ultimately decreases functional diversity of the same ecosystem. The effects of functional diversity on the productivity of an ecosystem can be quantitatively explained by the sampling effect model and the niche differentiation model. There are other proposed mechanisms like Niche complementarity and species redundancy relating functional diversity with ecosystem functioning. Rivets and idiosyncratic models relate functional diversity and species richness with ecosystem functioning. By considering the above proposed models on ecosystem functioning, it can be considered that functional diversity is a principal component of ecosystem functioning. So it can be assumed that, knowledge about a particular ecosystem reveals its richness and evenness which enable an individual knowing about the diversity of functional traits prevailing in the ecosystem. Thus, it opens up a new way in understanding and carrying out ecology related studies more efficiently and precisely in ecosystem.