Soil microorganisms have a crucial role in soil nutrient availability and plant growth. An IRNAS´ team, in collaboration with universities of Córdoba and Granada, have studied soil nutrients and microbial C, N and P pools in forests from three contrasted sites in South Spain: Sierra Nevada Park (Granada), Alcornocales Park (Cádiz) and Cardeña Park (Córdoba). The largest pool of microbial nutrients was measured in mixed forest (Q. suber – Q. canariensis) soil of Alcornocales Park (e. g., 378 mg kg-1 C) while the oak (Q. ilex) savannas in Cardeña and pine (P. sylvestris) forest in Sierra Nevada had lower values (circa 60 mg kg-1 C). Oak trees had a significant fertilizer effect on the microbial nutrient pools, compared to open sites: 120-170% higher for C, 130-230% for N and 180-220% for P. This study has been published in the number of July of the journal Plant and Soil.
Aponte et al. 2014. Plant and Soil 380: 57-72.