Using species distribution models with climate change scenarios to aid ecological restoration decisionmaking for southern California shrublands.
Abstract
Sourcing appropriate plant material for restoration within the heterogeneous landscape of southern California is a nuanced task further complicated by climate change. We generated species distribution models (SDMs) that may be useful tools for incorporating climate change scenarios into ecological restoration decisionmaking for southern California scrub and shrubland habitats. We modeled regional patterns of suitable habitat under baseline (1951-1980) and midcentury (2040-2069) climate conditions for 44 focal plant taxa under five future climate scenarios. Projected changes in habitat suitability varied across taxa and climate scenarios. Future climate scenarios with the most extreme directional changes in precipitation (increase or decrease) resulted in the greatest projected loss of suitable habitat for most taxa. The majority of plant taxa we modeled had a high degree of stable future habitat suitability, with 31 taxa projected to have ≥75 percent of baseline suitable habitat maintaining suitability midcentury under at least three future climate scenarios. Infraspecific differences in projected midcentury suitable habitat highlight the importance of considering varieties and subspecies when applying modeling results to conservation and natural resource management decisionmaking. While we did not explicitly model plant communities, multitaxon suitability overlays revealed patterns for alluvial scrub, coastal sage scrub, mixed chaparral-sage scrub, and low-elevation chaparral vegetation groups that were less readily apparent in individual taxon maps. We discuss caveats regarding SDMs and suggest that they could be used as part of an integrated toolset for successful application.