**5. Conclusions**

Soil bacterial communities have adapted to low rainfall at the Guánica Dry Forest; this could be a response to historical rainfall patterns encountered at the Guánica Dry Forest. The fact that 9 out of the 17 bacterial phyla identified were higher during the dry period supports this conclusion. For this forest, bacterial diversity did not change as a response to rainfall; however, equitability and richness changed demonstrating bacterial resilience. We are seeing how the same three bacterial phyla (*Proteobacteria*, *Actinobacteria*, and *Bacteroidetes*) are predominant during both dry and rainfall periods. Even though predominant bacterial phyla were the same during both periods under all tree species, differences were found at a finer scale. For instance, *Pisonia albida* had the soil with the most bacterial indicator species present. It is evident that this tree is shaping the soil microbiome in different ways. The general trend for predominant phyla found for Guánica is similar to the predominant phyla found in other terrestrial ecosystems even though the conditions of Guánica are unique. In the future, it would be nice to compare the sequences obtained in this study with other terrestrial environments but to the species level. This will help elucidate which are the species that could be playing important roles in ecosystem function and resilience.

### **Acknowledgements**

The project was funded by NSF Grant HRD-0734826 and is a contribution of the Centre of Applied Tropical Ecology and Conservation of the University of Puerto Rico. We appreciate the support of Mr. Larry Diaz, laboratory coordinator, and students from the Ecosystems Processes and Function laboratory of the University

*First Insights into the Resilience of the Soil Microbiome of a Tropical Dry Forest… DOI: http://dx.doi.org/10.5772/intechopen.90395*

of Puerto Rico, Río Piedras Campus, that participated in the field collection of soil samples. Special thanks to Dr. Verónica Acosta-Martínez for offering her comments and suggestions in the preparation of this manuscript.
