Conceptualizing ecosystem tipping points within a physiological framework.

摘要: Connecting the nonlinear and often counterintuitive physiological effects of multiple environmental drivers to emergent impacts on ecosystems is a fundamental challenge. Unfortunately, disconnect between way "stressors" (e.g., warming) considered in organismal (physiological) ecological (community) contexts continues hamper progress. Environmental typically elicit biphasic responses, where performance declines at levels above below some optimum. It also well understood that species exhibit highly variable response surfaces these changes so optimum level any driver can vary among interacting species. Thus, interactions are unlikely go unaltered under change. However, while nonlinear, species-specific relationships environment appear be general, rarely they incorporated into predictions tipping points. Instead, most ecosystem-level studies focus varying "stress" frequently assume deviation from "normal" conditions has similar effects, albeit with different magnitudes, all within community. We consider framework realigns positive negative climatic nonclimatic indirect responses. Using series simple models based direct responses temperature ocean pCO 2, we explore how variation environment-performance primary producers consumers translates community-level via trophic interactions. These show even absence mortality, mismatched resulting subtle physical lead substantial