Composición botánica del matorral sarcocaule en Baja California Sur durante las estaciones húmeda y seca

The aim of the present study was to determine the floristic composition of the sarcocaule scrub of the Sonoran desert in an area of 800 ha within an ejidal property located in the limits of the city of La Paz, Southern Baja California. Sampling was carried out during the rainy season (September-November 2018) and at the end of the dry season (May-August 2019), using 20 quadrants of 5 m × 5 m. 29 species of 1 634 individuals were identified, between the two seasons and the variables of height and crown diameter of each specimen by species were considered, in order to determine abundance (Ar), dominance (Dr), frequency (Fr), importance value index (IVI) and the Shannon index for species diversity (H´) and the Margalef index for species richness (S´). During the rainy season, Jatropha cinerea is observed as the dominant species Dr = 7.15 % and with the highest IVI (10.7 %) and Turnera diffusa as the most abundant with Ar = 3.2. On the other hand, for the dry season, Prosopis articulata is the dominant species Dr = 9.29 and with the highest IVI (12.51 %) and Mammillaria armillata as the most abundant, with Ar = 4.56. The indices of H' and S' during the rainy season were 3.36 and 8.09, respectively, with a difference between them (p≤0.05) when compared with those of the dry season (2.88 and 4.88, respectively), due to the absence of species and decrease in the number of individuals, than in the wet season.