Research on biodiversity-ecosystem function relationships

Recent research and vision

Given the many ongoing threats to global biodiversity, it is worth considering whether, or to what extent, ecosystem functions depend on biodiversity per se. At the root of this question is whether declines in biodiversity will create negative feedbacks that accelerate ecosystem decay as global change progresses. Understanding such a process would enable us to better predict how communities and ecosystems will respond to global change. And from a practical standpoint, the relationship between biodiversity and ecosystem function could provide important motivation for biodiversity conservation… if biodiversity is indeed important for ecosystem function.

In my recent work, I examined this question in the context of bee diversity and plant pollination. I found that, due to diet complementarity among wild bee species, diverse plant communities do indeed depend on a diverse bees assemblage. Notably, even locally rare bees can be important pollinators for some plant species (Simpson et al 2022. This work was purely observational, however, and does not consider demographic consequences to plants of pollinator visitation rates or pollinator diversity.

In my future work, I would like to more explicitly consider the role of diversity in population or community response to disturbance. While the classic biodiversity-ecosystem function (BEF) approach is compelling for its simplicity, I think it relies too heavily on implicit assumptions. For example, what functions are we measuring and why are some functional outcomes preferred over others? I think the root of the BEF question is, as I stated at the top, about whether biodiversity loss will destabilize ecosystems, creating negative feedbacks that accelerate ecosystem decay. Ultimately, “does biodiversity support biodiversity?” It is about more than functional rates—it is about population and community resilience.

To advance the BEF field, I would like to address this root question more directly, perhaps in the context of food webs. For example, how do common functional rates (e.g. productivity or nutrient cycling rates) relate to food web structure? Are there feedbacks between food web structure (e.g. diversity, complementarity or modularity) and functional rates that affect foodweb resilience?