Nurse Plants, soil modification and environmental filtering.

Background/Question/Methods

The pine forests on quartz sands in Pinar del Río, Cuba; represent extreme environments with a low load capacity for plant species, determined by the presence of almost pure quartz, very acid soils and poor in nutrients; In these sites, facilitation, with the nurse effect as its main exponent, has favored the conservation of its plant diversity. In the work, soil parameters of samples taken under the nurse plants canopy and in open spaces are compared and the relationship between soil enrichment, species recruitment and their occurrence category is analyzed. These samples were taken under 130 individuals of 13 species that were found assuming the role of nurses and 30 open spaces.

Results/Conclusions

As a result, it was obtained that under the nurse plants the soil conditions had significant differences with respect to the open spaces, in terms of organic matter content, cation exchange capacity and acidity levels, the last one resulting a key parameter in the creation of a filter. Inducing an exclusive advantage for the specialized plants of quartz sands, showing how the nurse effect has influenced the stability of the species composition of these fragile ecosystems and preserving a high endemism.