High fire frequency in California chaparral reduces post-fire shrub regeneration and native plant diversity

Fire is crucial for maintaining species diversity and resilience in fire-adapted shrublands of the world’s Mediterranean climate zones (MCZs), which include the chaparral shrublands of the North American MCZ. Chaparral is adapted to high intensity burning, with long intervals between fires (30-100 years) typifying undegraded conditions. In much of the range of chaparral, modern fire frequencies are much higher, driven largely by high densities of human ignitions and coincidence between ignitions and severe weather conditions. This change in the fire regime has major implications for biodiversity, leading to exotic invasion, decreased ecosystem services, and potential type conversion of shrubland to grassland dominated by exotic species. We studied the impact of increased fire frequencies on the composition and abundance of herbaceous and woody species in the Interior Coast Range of northern California. Our study area is one of the most frequently burned areas in California, which afford..., , , # High fire frequency in California chaparral reduces post-fire shrub regeneration and native plant diversity

We surveyed fifty-four 250-m2 plots to assess changes in plant community composition and postfire regeneration of chaparral shrubs across a wide range of fire frequencies, including plots that have burned up to six times in the past 30 years

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1) 'LNU_plot_description.csv'

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Dataset of all potential covariates used in the models.

Fields are as follows:

* Site: Unique site name. *QuailRidge* for Quail Ridge UC Natural Reserve (38°30’ N, 122°08’ W), *ColdCanyon* for Cold Canyon UC Natural Reserve (38°30’ N, 122°06’ W), *Bobcat* for Bobcat Ranch Audubon Reserve (38°31’ N, 122°04’ W), and *CacheCreek* for Berryessa Snow Mountain National Monument (38°54’ N, 122°18’ W) and Valley Vista Regional Park (38°54’ N, 122°16’ W)
* PlotID: A unique plot ID for each distinct transect.
* num_burn: The number of prior fires, according to the California Fire Return Interval Departure...