Biodiversity simultaneously enhances the production and stability of community biomass, but the effects are independent

Abstract

To predict the ecological consequences of biodiversity loss, researchers have spent much time and effort quantifying how biological variation affects the magnitude and stability of ecological processes that underlie the functioning of ecosystems. Here we add to this work by looking at how biodiversity jointly impacts two aspects of ecosystem functioning at once: (1) the production of biomass at any single point in time (biomass/area or biomass/ volume), and (2) the stability of biomass production through time (the CV of changes in total community biomass through time). While it is often assumed that biodiversity simultaneously enhances both of these aspects of ecosystem functioning, the joint distribution of data describing how species richness regulates productivity and stability has yet to be quantified. Furthermore, analyses have yet to examine how diversity effects on production covary with diversity effects on stability. To overcome these two gaps, we reanalyzed the data from 34 experiments that have manipulated the richness of terrestrial plants or aquatic algae and measured how this aspect of biodiversity affects community biomass at multiple time points. Our reanalysis confirms that biodiversity does indeed simultaneously enhance both the production and stability of biomass in experimental systems, and this is broadly true for terrestrial and aquatic primary producers. However, the strength of diversity effects on biomass production is independent of diversity effects on temporal stability. The independence of effect sizes leads to two important conclusions. First, while it may be generally true that biodiversity enhances both productivity and stability, it is also true that the highest levels of productivity in a diverse community are not associated with the highest levels of stability. Thus, on average, diversity does not maximize the various aspects of ecosystem functioning we might wish to achieve in conservation and management. Second, knowing how biodiversity affects productivity gives no information about how diversity affects stability (or vice versa). Therefore, to predict the ecological changes that occur in ecosystems after extinction, we will need to develop separate mechanistic models for each independent aspect of ecosystem functioning.

Species richness and biomass explain spatial turnover in ecosystem functioning across tropical and temperate ecosystems

“…In both the Indonesian and German study regions, increasing dissimilarity among communities also resulted in greater among-plot dissimilarity in total biomass. These results are confirmative of a multitude of previous studies showing that species richness drives patterns in productivity, especially for primary producer organisms [35,36]. Interestingly, we also found an effect of species composition on community biomass in the German litter communities, suggesting that the combined identities of particular species might be driving varying levels of biomass across these landscapes.…”

Arbuscular Mycorrhizal Fungi Enhance Plant Diversity, Density and Productivity of Spring Ephemeral Community in Desert Ecosystem

“…Numerous reports deal with ecological restoration through the establishment of planted vegetation and indicate that biodiversity restoration is an important condition for regional ecological health (Odum, 1989;Aronson et al, 2016). Biodiversity is not only closely related to biomass production (Tilman et al, 1996;Bullock et al, 2001;Cardinale et al, 2013), but is also related to ecosystem stability (Tilman, 1999;Eisenhauer et al, 2016). As expected, AMF can improve the plant density, species richness and diversity and plant productivity in desert herbland.…”

Biodiversity ecosystem functioning research in freshwater phytoplankton: A comprehensive review of trait-based studies

“…I first collected all previous reviews and meta-analyses on the topic of biodiversity and ecosystem functioning (BEF), irrespective of the organism included and checked for references on freshwater phytoplankton (Hooper et al, 2005;Srivastava and Vellend, 2005;Balvanera et al, 2006;Cardinale et al, 2009;Cardinale et al, 2011;Cardinale et al, 2013;Gross et al, 2014;Duffy et al, 2017). This was supplemented with a search of the ISI Web of Science database using the keyword sequence combining (freshwater OR lake OR pond OR reservoir) AND (phytoplankton* OR alga* OR diatom AND (community OR ecosystem) AND (function* OR product* OR biomass OR biovolume OR resource use).…”