Scaling environmental change through the community‐level: a trait‐based response‐and‐effect framework for plants

Abstract

Predicting ecosystem responses to global change is a major challenge in ecology. A critical step in that challenge is to understand how changing environmental conditions influence processes across levels of ecological organization. While direct scaling from individual to ecosystem dynamics can lead to robust and mechanistic predictions, new approaches are needed to appropriately translate questions through the community level. Species invasion, loss, and turnover all necessitate this scaling through community processes, but predicting how such changes may influence ecosystem function is notoriously difficult. We suggest that community-level dynamics can be incorporated into scaling predictions using a trait-based response-effect framework that differentiates the community response to environmental change (predicted by response traits) and the effect of that change on ecosystem processes (predicted by effect traits). We develop a response-and-effect functional framework, concentrating on how the relationships among species' response, effect, and abundance can lead to general predictions concerning the magnitude and direction of the influence of environmental change on function. We then detail several key research directions needed to better scale the effects of environmental change through the community level. These include (1) effect and response trait characterization, (2) linkages between response-and-effect traits, (3) the importance of species interactions on trait expression, and (4) incorporation of feedbacks across multiple temporal scales. Increasing rates of extinction and invasion that are modifying communities worldwide make such a research agenda imperative.

A safe operating space for humanity

“…Species loss therefore affects both the functioning of ecosystems and their potential to respond and adapt to changes in physical and biotic conditions (Elmqvist et al 2003, Suding et al 2008). …”

Biodiversity and Resilience of Ecosystem Functions

“…This ignores the need to ensure that essential ecosystem functions will be provided 53 under a range of environmental perturbations that could occur in the near future (i.e. the 54 provision of resilient ecosystem functions). The objective of this review is to identify the 55 range of mechanisms which underpin the provision of resilient ecosystem functions to 56 inform better environmental monitoring and management.…”

Integrating plant ecological responses to climate extremes from individual to ecosystem levels

“…For example, a trait that is highly responsive to drought stress, such as flowering in mesic grassland, may also have detectable feedback effects on ecosystem productivity due to the large investment of carbon in flowering stalks [22]. However, response and effect traits of plants may not necessarily be tightly coupled, and thus those traits responsible for driving plant community compositional change during or after an extreme may not translate to detectable impacts on ecosystem function, such as productivity [17,21]. For example, traits that are highly sensitive to stress, such as photosynthetic responses to drought, may buffer impacts to ecosystem productivity by increasing water-use efficiency of species in the community.…”

“…Suding et al [17] proposed that community dynamics often complicate scaling up from the individual level, and that plant community processes may be scaled to ecosystem productivity by relating species abundances with their functional traits. Only recently have ecologists begun to explicitly consider how responses to climate extremes at lower ecological levels, such as individual mortality, will scale to ecosystem-level processes, such as carbon and water cycling [18].…”