Productivity is a poor predictor of plant species richness.
Adler PB., Seabloom EW., Borer ET., Hillebrand H., Hautier Y., Hector A., Harpole WS., O'Halloran LR., Grace JB., Anderson TM., Bakker JD., Biederman LA., Brown CS., Buckley YM., Calabrese LB., Chu CJ., Cleland EE., Collins SL., Cottingham KL., Crawley MJ., Damschen EI., Davies KF., DeCrappeo NM., Fay PA., Firn J., Frater P., Gasarch EI., Gruner DS., Hagenah N., Hille Ris Lambers J., Humphries H., Jin VL., Kay AD., Kirkman KP., Klein JA., Knops JM., La Pierre KJ., Lambrinos JG., Li W., MacDougall AS., McCulley RL., Melbourne BA., Mitchell CE., Moore JL., Morgan JW., Mortensen B., Orrock JL., Prober SM., Pyke DA., Risch AC., Schuetz M., Smith MD., Stevens CJ., Sullivan LL., Wang G., Wragg PD., Wright JP., Yang LH.
For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters(-2)) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity and richness.