SignificanceEcological research suggests that greater biodiversity could lead to greater economic value, even for private owners of "working" land. But the studies from which such a conclusion might be inferred do not account for all relevant information in a coherent economic framework. Our paper applies standard economic theory to rigorously account for costs, quality and risk. Results indicate that higher levels of biodiversity than typically observed on commercial grasslands would maximize landowner value in the experimental grassland we study. Greater private benefits from biodiversity could encourage private investment in biodiversity and reduce the cost of public conservation efforts.
AbstractThe biodiversity-ecosystem functioning (BEF) literature provides strong evidence of the biophysical basis for the potential profitability of greater diversity but does not address questions of optimal management. BEF studies typically focus on the ecosystem outputs produced by randomly-assembled communities that only differ in their biodiversity levels, measured by indices like species richness. Landholders, however, do not randomly select species to plant; they choose particular species that collectively maximize profits. As such, their interest is not in comparing the average performance of randomly-assembled communities at each level of biodiversity but rather comparing the best-performing communities at each diversity level. Assessing the best-performing mixture requires detailed accounting of species' identities and relative abundances. It also requires accounting for the financial cost of individual species' seeds, and the economic value of changes in the quality, quantity and variability of the species' collective output--something that existing multifunctionality indices fail to do. This study presents an assessment approach that integrates the relevant factors into a single, coherent framework. It uses ecological production functions to inform an economic model consistent with the utilitymaximizing decisions of a potentially risk-averse private landowner. We demonstrate the salience and applicability of the framework using data from an experimental grassland to estimate production relationships for hay and carbon storage. For that case, our results suggest that even a risk-neutral, profit-maximizing landowner would favor a highly diverse mix of species, with optimal species richness falling between the low levels currently found in commercial grasslands and the high levels found in natural grasslands.