The Postfire Conifer Reforestation Planning Tool (PostCRPT) seeks to answer the questions of where conifers will regenerate on their own after wildfire and, conversely, where conifer reforestation efforts might be targeted. The app is designed to simplify the process of creating predictive maps of postfire conifer regeneration.
PostCRPT predicts the probability of post-fire conifer regeneration under varying postfire precipitation and seed production scenarios. The predictive model was fit using data from 1,234 plots, spanning 19 wildfires, each measured five years after wildfire. PostCRPT predicts the probability that regeneration will occur within 4.4-m radius (60 m2) plots across the burn footprint. Refer to Stewart et al. (2021) for details.
The app requires the user to input a zip file containing a fire perimeter and a raster of burn severity (RdNBR). The RAVG website has both RdNBR and fire perimeter data sets available for all fires with at least 1,000 acres of National Forest land from 2007 to the present. A sample dataset is also available in the about tab of the tool.
Confidence intervals for the PostCRPT statistical models are visualized using reliability diagrams (below). The reliability diagrams depict the performance of PostCRPT predictions when applied to new data, and were created using leave-one-fire-out cross-validation. Predictive performance is high in the all-Conifer and fir (Abies) models. The pine (Pinus) model has much room for improvement. See Stewart et al. (2021) for a full discussion.
Seeking to follow the principle of Ockham’s razor, PostCRPT uses just six input variables to predict the probability of regeneration. The variables are seed availability, burn severity, historical precipitation, postfire precipitation anomaly, slope, and aspect. Other candidate variables either did not improve out-of-sample model performance or resulted in response functions that appeared to be the result of overfitting.
PostCRPT is a user interface for models developed by:
PostCRPT batch processed outputs preview – April 2023. We’re working on updates to the underlying statistical models (including an expanded dataset) and batch processed PostCRPT predictions for CA and southern OR. This interface displays some early progress toward these objectives. The current coverage in this interface is CA-wide for all 2012-2021 fires. Unlike version 0.123, this version accounts for seed availability estimates from all conifer species mapped in CA and OR, not just the ones that are represented in the Stewart et al. (2021) dataset. To request access to preliminary versions of batch-proccessed predictions in raster format contact Joe Stewart.
PostCRPT version 0.123 – Released January, 2022. Allows users to incorporate the effects of multiple sequential fires. Uses the 2020 version of LEMMA GNN forest structure maps. Updates the Stewart et al (2021) regeneration model to use 2020 version of GNN structure maps. Adds useful warnings. Expands geographic coverage. Refines the spatial domain.
PostCRPT version 0.100 – Released January, 2021. This initial release of the app cannot account for multiple sequential burns occurring after 2012. It uses the original Stewart et al (2021) regeneration models and the 2012 version of GNN basal area maps. It was adapted for the web from poscrptR and incorporates only small modifications of the poscrptR code.