Consequences of biodiversity loss for litter decomposition across biomes

• Published in: Nature (London) 2014-05, Vol.509 (7499), p.218-221
• Main Authors: Handa, I. Tanya, Aerts, Rien, Berendse, Frank, Berg, Matty P., Bruder, Andreas, Butenschoen, Olaf, Chauvet, Eric, Gessner, Mark O., Jabiol, Jérémy, Makkonen, Marika, McKie, Brendan G., Malmqvist, Björn, Peeters, Edwin T. H. M., Scheu, Stefan, Schmid, Bernhard, van Ruijven, Jasper, Vos, Veronique C. A., Hättenschwiler, Stephan
• Format: Article
• Language: English
• Subjects: 704/158/670; Aquatic ecosystems; Arctic Regions; Biodiversity; Biodiversity and Ecology; Biodiversity loss; Biological diversity; Biomass; Biosphere; Botanical research; Carbon; Carbon - metabolism; Carbon Cycle; climate; Decomposition; Ecology; Ecosystem; Ecosystems; Ekologi; Endangered & extinct species; Environmental aspects; Environmental Sciences; Experiments; Field tests; Humanities and Social Sciences; leaf-litter; letter; Litter; multidisciplinary; Nitrogen; Nitrogen - metabolism; Nitrogen Cycle; Nitrogen fixation; Nutrient cycles; Organic matter; patterns; Plant populations; Plants - metabolism; Science; services; species functional diversity; traits; Tropical Climate; Tropical environments
• ISSN: 0028-0836; 1476-4687; 1476-4687
• DOI: 10.1038/nature13247

Field experiments across aquatic and terrestrial ecosystems show that biodiversity positively affects carbon and nitrogen cycling in leaf litter decomposition, indicating that reduced decomposition caused by biodiversity loss would modify the global carbon cycle and limit the nitrogen supply to the organisms at the base of the food chain. Plant litter diversity in ecosystem function It is well established that biodiversity has a positive effect on ecosystem functions such as primary production, but its effects on the diversity of plant litter and of the organisms that break it down are less clear cut. Stephan Hättenschwiler and colleagues examined litter diversity in parallel manipulative experiments at five sites ranging from subarctic to tropical, and including both aquatic and terrestrial ecosystems. Across all of the studied ecosystems, they show that reducing the diversity of litter or of detritivores (the invertebrates and microorganisms that break litter down) slows litter carbon and nitrogen cycling and the rate of decomposition. A reduction in decomposition caused by biodiversity loss would, for example, limit the nitrogen supply to primary producers. Although positive overall, the effects were weaker than commonly reported for primary production, thus challenging current thinking on the generality of relationships between biodiversity and ecosystem processes that are based on assessments of plant productivity. The decomposition of dead organic matter is a major determinant of carbon and nutrient cycling in ecosystems, and of carbon fluxes between the biosphere and the atmosphere 1 , 2 , 3 . Decomposition is driven by a vast diversity of organisms that are structured in complex food webs 2 , 4 . Identifying the mechanisms underlying the effects of biodiversity on decomposition is critical 4 , 5 , 6 given the rapid loss of species worldwide and the effects of this loss on human well-being 7 , 8 , 9 . Yet despite comprehensive syntheses of studies on how biodiversity affects litter decomposition 4 , 5 , 6 , 10 , key questions remain, including when, where and how biodiversity has a role and whether general patterns and mechanisms occur across ecosystems and different functional types of organism 4 , 9 , 10 , 11 , 12 . Here, in field experiments across five terrestrial and aquatic locations, ranging from the subarctic to the tropics, we show that reducing the functional diversity of decomposer organisms and plant litter types slowed the cycling of li