The relationship between diversity and productivity in plant communities: facts and artefacts

Numerous explanatory theories have been developed about patterns found in nature. One such pattern is the tendency of the relationship between plant species richness and above-ground biomass to be unimodal when exploring an environment gradient. Since it was first described by Al-Mufti et al. in 1977, the trend has been examined extensively by other researchers using more rigorous calculation tools. These include Rosenzweig and Abramsky (1993) who formulated nine hypotheses regarding the relationship of productivity. Oksanen (1996) developed a 10th hypothesis known as the non-interaction model.