Submitted to: Grassland Science in Europe
Publication Type: Proceedings
Publication Acceptance Date: April 16, 2008
Publication Date: June 8, 2008
Citation: Sanderson, M.A. 2008. Are herbage yield and yield stability affected by plant species diversity in sown pasture mixtures? Grassland Science in Europe 11:512-514. Technical Abstract: A tenet of plant biodiversity theory in grasslands is that increased diversity contributes to the stability of ecosystems. In managed grasslands, such as pastures, greater stability of herbage production as a result of increased plant species diversity would be beneficial. In this study, I combined historical data from pasture mixture experiments conducted during the 1930s to 1960s in the USA along with more recent data from my laboratory to determine the relationships among herbage yield, stability of yield (measured as the relative standard deviation, RSD), and diversity indices (species richness, Shannon H, and evenness). In nearly all studies, mixtures yielded more herbage than monocultures and the RSD of yield across years was less for mixtures than monocultures. There was a wide variation in the derived relationships within mixtures, however, and in many instances there was no relationship between herbage yield or yield stability and the complexity of the mixture.