Understanding abiotic and biotic drivers of plant establishment processes to anticipate future ecological resilience

Alexandra Urza

Publication Date:

Global climate change is expected to decrease the resilience of many ecosystems, reducing their ability to recover to prior states following disturbance. Direct effects may include increasingly unsuitable conditions for post-disturbance recruitment and survival, which will have significant effects on restoration success. These effects can be largely inferred based on differential species establishment across climatic gradients. However, primary effects of climate shifts will be not only on the underlying abiotic environment, but also on disturbance regimes, species invasions, and species interactions, including both competition and facilitation. Anticipating these impacts requires a mechanistic understanding of the processes underlying plant community dynamics. Here, we provide the conceptual basis for evaluating these effects. We provide a case study from semiarid woodlands of the western USA, where warmer temperatures coupled with annual grass invasions are increasing the frequency and extent of wildfires. Post-fire woodland recovery requires successful tree regeneration, but seedling establishment is largely limited to favorable under-shrub microsites that modify the harsh abiotic environment. Nurse shrub recovery is expected to be diminished by warming and annual grass invasions in some portions of the landscape, decreasing the availability of favorable microsites for tree regeneration, even where climatic conditions are generally suitable. A process-based understanding of how biotic interactions and multi-species responses to disturbance vary across the landscape can be used to assess ecological resilience and anticipate ecosystem responses to future environmental change to both prioritize restoration efforts and determine the most effective strategies.

Resource Type:
Audio/Video, Conference Presentation, SER2019

Pre-approved for CECs under SER's CERP program

Society for Ecological Restoration