Biodiversity and Ecosystem Functioning

Abstract

Species diversity is a major determinant of ecosystem productivity, stability, invasibility, and nutrient dynamics. Hundreds of studies spanning terrestrial, aquatic, and marine ecosystems show that high-diversity mixtures are approximately twice as productive as monocultures of the same species and that this difference increases through time. These impacts of higher diversity have multiple causes, including interspecific complementarity, greater use of limiting resources, decreased herbivory and disease, and nutrient-cycling feedbacks that increase nutrient stores and supply rates over the long term. These experimentally observed effects of diversity are consistent with predictions based on a variety of theories that share a common feature: All have trade-off-based mechanisms that allow long-term coexistence of many different competing species. Diversity loss has an effect as great as, or greater than, the effects of herbivory, fire, drought, nitrogen addition, elevated CO2, and other drivers of environmental change. The preservation, conservation, and restoration of biodiversity should be a high global priority.

Biodiversity explains maximum variation in productivity under experimental warming, nitrogen addition, and grazing in mountain grasslands

“…This was consistent with a review by Tilman et al. (2014), in which the diversity effect is as great as, or greater than, the effects of herbivory, nitrogen addition, and other drivers of environmental change. Although our experiment is limited in the short term by the drivers of environmental change, our results still supported a strong positive species richness–productivity relationship in natural ecosystems even after quantifying the effects of intraspecific trait variability and evolutionary history.…”

“…The relationship between plant biodiversity and ecosystem function has been a major research topic in ecology for several decades, and while there is general empirical support for a positive effect of biodiversity on function from manipulative experiments (Balvanera et al., 2006; Cardinale et al., 2006; Tilman, Isbell, & Cowles, 2014), there is a lack of clarity about how anthropogenic changes in plant biodiversity might affect biomass production in more natural systems (Zavaleta & Hulvey, 2007). Inconsistent biodiversity effects on productivity could result from how biodiversity is measured, the confounding effect of environmental heterogeneity, and the nature of the anthropogenic impacts.…”

Grassland biodiversity can pay

“…These values bracket all but the lowest of the four social cost estimates recommended for use in U.S. government regulatory analyses (35). Estimates of the coefficient of relative risk aversion in agriculture vary widely, and we explore the implications for optimal species composition of a correspondingly wide range of values, [0,2,4]. To put these parameter values in context, the certainty equivalent value of a gamble to win $100 or lose $50 with equal probability would be $25, $2.50, and $0.25, respectively, given the utility function identified above.…”

“…Increasingly, evidence points to the important causative role of species diversity in promoting ecosystem functioning and stability (1,2). Experimental evidence shows that, on average, as the level of diversity rises so too do measures of ecosystem functioning, such as primary production and carbon storage.…”

Low functional diversity promotes niche changes in natural island pollinator communities

“…Such effects have been reported for various taxonomic groups in the past decade (e.g. plants [4], insects [5], birds, and mammals [6]) and have become a central issue of basic and applied ecology [7][8][9]. Functional diversity loss in pollinators, which are crucial to maintaining wild plant diversity and crop production, has progressed rapidly across the globe [10,11].…”