A gran muralla verde

http://www.greatgreenwall.org/great-green-wall/#great-green-wall-internal

http://elpais.com/elpais/2016/05/05/planeta_futuro/1462456389_062506.html?rel=mas

http://bosquessostenibles.com/blog2/?p=872

http://elpais.com/elpais/2014/08/08/planeta_futuro/1407493132_336973.html

https://www.youtube.com/watch?v=pc3BTMVPIwc

https://www.youtube.com/watch?v=FhmK0vnZPSU