title: Exponential decline of deep-sea ecosystem functioning linked to benthic biodiversity loss.
abstract: BACKGROUND
  Recent investigations suggest that biodiversity loss might impair the functioning and sustainability of ecosystems. Although deep-sea ecosystems are the most extensive on Earth, represent the largest reservoir of biomass, and host a large proportion of undiscovered biodiversity, the data needed to evaluate the consequences of biodiversity loss on the ocean floor are completely lacking.
  
  
  RESULTS
  Here, we present a global-scale study based on 116 deep-sea sites that relates benthic biodiversity to several independent indicators of ecosystem functioning and efficiency. We show that deep-sea ecosystem functioning is exponentially related to deep-sea biodiversity and that ecosystem efficiency is also exponentially linked to functional biodiversity. These results suggest that a higher biodiversity supports higher rates of ecosystem processes and an increased efficiency with which these processes are performed. The exponential relationships presented here, being consistent across a wide range of deep-sea ecosystems, suggest that mutually positive functional interactions (ecological facilitation) can be common in the largest biome of our biosphere.
  
  
  CONCLUSIONS
  Our results suggest that a biodiversity loss in deep-sea ecosystems might be associated with exponential reductions of their functions. Because the deep sea plays a key role in ecological and biogeochemical processes at a global scale, this study provides scientific evidence that the conservation of deep-sea biodiversity is a priority for a sustainable functioning of the worlds' oceans.
authors.affiliation: Department of Marine Science, Faculty of Science, Polytechnic University of Marche, Via Brecce Bianche, 60131 Ancona, Italy. r.danovaro@univpm.it
authors.forename: Roberto
authors.initials: R
authors.lastname: Danovaro
authors.forename: Cristina
authors.initials: C
authors.lastname: Gambi
authors.forename: Antonio
authors.initials: A
authors.lastname: Dell'Anno
authors.forename: Cinzia
authors.initials: C
authors.lastname: Corinaldesi
authors.forename: Simonetta
authors.initials: S
authors.lastname: Fraschetti
authors.forename: Ann
authors.initials: A
authors.lastname: Vanreusel
authors.forename: Magda
authors.initials: M
authors.lastname: Vincx
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Gooday
mesh_terms: D044822:Biodiversity; D018533:Biomass; D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D020387:Food Chain; D009792:Oceans and Seas; D010100:Oxygen / Q000032:analysis; D012623:Seawater / Q000737:chemistry
chemical_list: D002244:Carbon; D010100:Oxygen