1. Department of Forest Ecology & Genetics, Forest Research Centre (ICIFOR-INIA, CSIC), Ctra. de la Coruña km 7.5 , Madrid, 28040 , Spain
2. Ecological and Forestry Applications Research Centre, CREAF , Campus de Bellaterra (UAB) 10 Edifici C, Cerdanyola del Vallès, 08193 , Spain