Fig 1.
Distribution of studied species.
1a: Historical distribution (red stripes) of Gentianella praecox subsp. bohemica in central Europe. 1b: Historical distribution (red stripes) and locations where Gentianella obtusifolia subsp. sturmiana is currently occurring (black dots) in the Czech Republic. Reviews of herbarium specimens and historical records were used to define the historical distribution.
Table 1.
Results of forward selection in CCA.
Environmental variables as explanatory variables of species composition at the sites where Bohemian gentian occurs. Significant p-values are marked by *.
Fig 2.
Fluctuation in population sizes of Bohemian gentian over the period 1999–2019.
Different lines show different Bohemian gentian populations.
Table 2.
Effect of environmental variables and type of management on population size of the Bohemian gentian. Significant p-values are marked *.
Fig 3.
The proportion of sites that were managed with five different management types before and after implementation the Bohemian gentian rescue programme.
Fig 4.
Diagram of the results of the canonical correspondent analysis—Correlation between vegetation composition and type of management and average population size of Bohemian gentian populations.
Mng1, Mng2, Mng3, Mng4, Mng5 –types of management; LogAvgPopSize—Average of population size (x+1). Abbreviations of the species names are in Appendix 1.
Fig 5.
Changes in population slope recorded after the implementation of the BGR programme.
Percentage of incidences when the slope, i.e. trend in the size of the population, either increased (“UP”) or decreased (“DOWN”) at the sites with one of four types of management. Mng1, Mng2, Mng3, Mng4 –management Type 1, 2, 3, 4.
Fig 6.
Average population sizes of the Bohemian gentians, calculated as total number of all flowering plants divided by number of locations, where gentians were recorded in that year.
Table 3.
Results of forward selection in CCA.
Environmental variables as explanatory variables of species composition at the sites where the Bohemian gentian and Sturmian gentian occur. Significant p-values are marked by *.
Table 4.
The soil parameters recorded in soil samples collected from the sites where the Bohemian gentian and Sturmian gentian occur were compared. Significant p-values are marked by *.
Fig 7.
Numbers of plants of the Sturmian gentian (G. obtusifolia subsp. sturmiana), in year t relative to the incidence of gaps in year t − 2.
Different letters indicate statistically significant differences in the numbers of plants (Duncan test).