https://digitalcommons.calpoly.edu/nres_rpt/24
Date of Award
12-2021
Degree Name
MS in Environmental Sciences and Management
Department
Natural Resources Management
College
College of Agriculture, Food, and Environmental Sciences
Advisor
Deidre Sommerlad-Rodgers
Advisor Department
Natural Resources Management
Advisor College
College of Agriculture, Food, and Environmental Sciences
Abstract
Climate induced increases in fire frequency and severity along with years of fire suppression and drought are predicted for California. The recent CZU Lightning Complex, a high severity wildfire, burned in the Santa Cruz Mountains on California’s central coast and affected an assortment of vegetation, including the survival and recovery of the native Año Nuevo Monterey pine (Pinus radiata (D. Don)) stand. This stand is partially located in Cal Poly’s Swanton Pacific Ranch and has been monitored for over 20 years for the presence of pitch canker (Fusarium circinatum) fungal disease. This study characterized the survival and initial recovery of vegetation approximately nine months after the fire. To better understand the influence of the CZU Lightning Complex on the vegetation within the 14 measured plots, we used a photo log to collect the vegetation surface area, height, and volume. In this work, we examined the vegetation density and its relationship with burn severity and slope. The regeneration variables and vegetation were observed in maps in ArcGIS Pro. The relationship between burn severity and regeneration dynamics suggested a moderate but negative correlation (r = -0.68) where short-term regeneration was less dense when severity was higher with a significant relationship (p = 0.008). The results from burn severity suggested better correlation to vegetation than those implied from the correlation to slope (r = 0.26), suggesting no significant relationship between slope and vegetation (p = 0.37). Observed recovery of understory density was modest in some plots and robust in others but included the reemergence of Monterey pines seedlings. Further studies should focus on continuing to monitor the post-fire vegetation regeneration in the plots as a longitudinal study of the Monterey pines.