Fig 1.
Schematic workflow of the proposed framework for biogeographic regionalization and spatial analysis at the regional level.
Each panel shows the analysis carried out and the inputs used.
Fig 2.
Location of the Floristic Province of Balsas Depression in Mexico (dark grey area).
Distribution of seasonally dry tropical forest (yellow area) in this floristic province, divided in squares of 0.25° × 0.25° arc-min.
Fig 3.
Cluster analysis (β-Simpson dissimilarity coefficient) showing the floristic dissimilarity of the grid squares with the Asteraceae species from the seasonally dry tropical forest in the Balsas Depression, Mexico.
(a) Dendrogram showing floristic dissimilarity. (b) Balsas Depression where the colors correspond to the groups shown in the dendrogram.
Fig 4.
Phytogeographic subdivision of the seasonally dry tropical forest in the Balsas Depression, Mexico.
The purple biogeographic track links by means of a minimum spanning tree the collecting points of the species exclusive to the Lower Balsas and the blue line those of the Upper Balsas.
Fig 5.
Asteraceae species turnover measured with the non-metric multidimensional scaling method (NMDS) for (a) axis 1 (NMDS1) and (b) axis 2 (NMDS2). The colors mark the two turnover ordering classes.
Fig 6.
NMDS ordination and environmental predictors (vectors) as predictors of environmental turnover, calculated for 122 grid cells, distributed along the Balsas Depression, Mexico.
The vectors shown include only the variables with a significant effect (p <0.001) on the NMDS ranking. BIO_15: Precipitation Seasonality (coefficient of variation in %); BIO_17: Precipitation of the driest four-month period; MEXMG: Magnesium content; MEXCA: Calcium content. The circles correspond to the grid cells of the Upper Balsas and the triangles to the cells of the Lower Balsas.
Table 1.
Variables that constitute the most parsimonious model of redundancy analysis.