Root functional traits in Mediterranean forests and shrublands

Roots have a fundamental role in plant function (uptake and storage of water and nutrients), as well as in ecosystem properties (primary productivity). Root activities are related with structural traits, such as diameter, density and specific area. However, there are few studies about the importance of functional root traits in Mediterranean environments.

A research team of the IRNAS, CSIC and the RESTECO project, in collaboration with the University of Córdoba, have explored the variation of root traits for 80 woody species (trees and shrubs) along a regional gradient in south Spain, covering from 200 up to 2000 mm of annual rainfall.

In general, strong relationships were found among the root traits. For example, those woody species with higher root specific area had thinner roots and lower tissue density. The main variation trend was interpreted as the “root economics spectrum”. However, the root diameter was not aligned along this main axis. We suggest to study other traits and to explore the existence of multidimensional root traits spectrum.

Soil water and nutrient availability was the main driver of variation among the root traits. Thus, plant communities growing in more productive environments were dominated by those species having root traits associated with rapid acquisition of resources. The foreseen reduction in water availability, caused by climate change, will limit species diversity and modify functioning of forest communities.

This study was published on line (October 23, 2017) in the journal Plant and Soil as part of a monographic issue on root traits.

de la Riva, E.G., Marañón, T., Pérez-Ramos, I.M., Navarro-Fernández, C.M., Olmo, M., Villar, R. (2017). Root traits across environmental gradients in Mediterranean woody communities: are they aligned along the root economics spectrum? Plant and Soil.