Data analysis

Los resultados de esta tesis permiten afirmar que la restauración pasiva puede llegar a ser una poderosa he- rramienta de restauración ecológica de los márgenes de las carreteras siempre que se den las condiciones idó- neas tanto en el propio margen como en el entorno cer- cano. Por tanto, para potenciar la restauración pasiva de estos ecosistemas nóveles, los resultados de esta tesis plantean dos líneas de actuación. Por un lado, se puede actuar a nivel de los propios márgenes para que las se- millas y propágulos que lleguen encuentren micrositios favorables para su establecimiento. Esta línea es sobre la que tradicionalmente se ha hecho más hincapié, ac- tuando sobre los componentes geomorfológicos (por ejemplo, pendiente del talud), edáficos (por ejemplo, aportes de tierra vegetal) o biológicos (por ejemplo, plan- taciones e hidrosiembras) del sistema. Por otro lado, la actuación puede realizarse a nivel de los entornos más cercanos, conservando en ellos la vegetación natural y su capacidad de dispersión. En la construcción de una nueva infraestructura o en la gestión durante la fase de funcionamiento, parece más interesantes conservar re- manentes de vegetación natural cercanos a los márge- nes de la carretera, que gastar dinero en plantaciones.

La restauración pasiva realizada bajo estas premisas tiene capacidad de mejorar la conservación de la diver-

sidad biológica en ambientes agrícolas, ya que mantiene el pool regional de especies y permite que se establezcan flujos ecológicos entre los márgenes de las carreteras y sus entornos. Además, también ayuda a minimizar los costes de mantenimiento de las carreteras, reduciendo los pasivos ambientales para las empresas y gobiernos que mantienen las infraestructuras. Sin embargo, la restauración pasiva requiere tiempo y necesita conjugar los objetivos técnicos a corto plazo, principalmente dis- minuir la erosión para no comprometer la estabilidad de la vía, con los objetivos de restauración ecológica a medio y largo plazo, focalizados en obtener beneficios ambientales como la conservación de la biodiversidad o la mejora de algunos servicios ecosistémicos debilita- dos. Por tanto, los esfuerzos se deben orientar hacia el desarrollo de planes de restauración que combinen los objetivos planteados a diferentes escalas espaciales y temporales.

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Conclusiones