Cuban serpentine thicket shifts to less diverse and more flammable stage becuase of fires

Background/Question/Methods

Fires create habitats plenty of resources like space, light, and nutrients suitable for plant development. They contribute to the maintenance of species diversity and structure in most plant communities but sometimes fires may change the community pathway. In this work, the species diversity, structure and plant recruitment of burned and unburned serpentine tickets of the serpentine region of Santa Clara, Cuba are compared.

Results/Conclusions

Species richness is lower in burned thickets but the difference is only significantly for the shrub layer (U = 0,00; p < 0,001). It is also significantly lower the richness (U = 3,50; p < 0,001) and abundance (U = 4,00; p < 0,001) of endemic species but higher the both parameters for non-native species (U = 32,0; p < 0,001). The shrub layer density (U = 39,0; p < 0,001) and cover (Kolmogorov-Smirnov; p < 0,001) are significantly higher in unburned thickets than in the burned ones. Instead the herb layer density is more dense and extensive in burned thickets than in unburned sites. The richness and abundance of native young plants are higher in unburned tickets and both decrease with the increase of herb layer cover (r = -0,83; n = 16; p < 0,05). According to our data, fires are promoting the development of poorer thickets and changing the flammability of the serpentine vegetation of the Santa Clara serpentine region. Both the composition and the structure of the fire-promoted thickets inhibited the natural recovery of the typical vegetation by limiting native plant recruitment.