Post-Fire Vegetation Recovery
Rémi Bardou
Gretchen Keppel-Aleks
Paige Fischer
Stella Cousins
Heidi Huber-Stearns
The Forest Steward's Guild
Vegetation Recovery and Species Shifts in a Changing Climate:
Informing Replanting or Forest Planning/Reseeding Decision Making in New Mexico
Purpose
Fire-suppressed forests and ecologically managed forests respond to and recover from fire events in vastly different ways. Understanding the role of climate variations and human intervention in post-fire recovery informs our ability to evaluate the overall carbon balance of forests, which is important for understanding climate feedback from a natural sciences perspective. Moreover, climate feedbacks that influence the post-fire establishment window inform time-sensitive forest management decisions, such as reforestation plans. As climate change continues to affect seasonal weather patterns, the need for this type of information is growing in places in the west that have experienced wildfires and restoration challenges in determining when, where, what and how to replant.
Approach
Research Question
How do post fire conditions affect vegetation change, and what are the implications for:
1. vegetation recovery,
2. ecological community change, and
3. manager/practitioner decision making?
Objectives
Examine how forest health and species composition can be impacted as a result of changes in environmental conditions and forest management.
Investigate the importance of extreme events such as rainfall variability and heatwaves related to the early stages of forest recovery and replanting efforts.
Provide biophysical insights on fire damage and recovery, which could potentially be adapted to inform and impact forest management decisions.
Methodology
This project first used remote sensing and climate modeling to understand vegetation change of western forests due to environmental variability, climate change and human intervention. Second, the we applied this understanding to post fire management strategies and decision making such as planning and reseeding strategies.
Landsat near-infrared bands are a great tool for detecting vegetation change from space
NDVI: Normalized Difference Vegetation Index
Post-fire vegetation change in NDVI following the Black Fire on May 21, 2022
Analysis
Moisture delivered in first couple of years post-fire seems to be strongly correlated to recovery. This is particularly important for New Mexico where post-fire vegetation recovery is getting more challenging under a changing climate
Lag analysis showed that it is not the total moisture that matters most, but the seasonality of it. This has implications for informing post-fire forest management decision-making.
Key Findings and Recommendations for Practice
Prioritizing and paying close attention to the initial years following a fire
Informing practitioners and forest managers (replanting and/or recovery decisions)
Seasonal outlooks on likelihood of reforestation success
Spatial patterns of post-fire recovery within fire scars
Go beyond Landsat-based NDVI (Normalized Difference Vegetation Index)