Article

Bases ecológicas para la restauración de los espartales semiáridos degradados

Ecosistemas: Revista científica y técnica de ecología y medio ambiente, ISSN 1697-2473, Nº. 1, 2003 01/2003;
Source: OAI

ABSTRACT Los espartales de Stipa tenacissima constituyen una de las formaciones más características de las zonas semiáridas mediterráneas. Algunas especies leñosas características de la vegetación que se considera potencial en estas zonas han desaparecido o bien se han visto restringidas a manchas discontinuas. En este estudio se analiza la interacción entre S. tenacissima y distintas especies leñosas mediterráneas introducidas mediante plantación y siembra, con el fin de evaluar el potencial de la facilitación como herramienta para la restauración ecológica de los espartales. Esta interacción es la suma de efectos positivos (mejora en las condiciones microclimáticas y edáficas y captación de agua de escorrentía) y negativos (competencia subterránea por el agua), siendo la mejora del microclima en los alrededores de S. tenacissima el principal mecanismo responsable de la facilitación observada en las especies introducidas. Los efectos positivos aumentan conforme lo hacen las condiciones climáticas adversas en un gradiente espacio-temporal de estrés hídrico.Estos resultados indican que la facilitación puede contribuir a optimizar la restauración de los espartales degradados.

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