As a consequence of the megadrought in Central Chile, it is expected that most of the distribution of woody species will be narrowed in the northern limits because of restrictions imposed by soil matric potential on seed germination. In this study, we analyzed the effect of the soil matric potential on seed germination and initial recruitment of the sclerophyllous species Prosopis chilensis, Quillaja saponaria and Cryptocarya alba from contrasting geographic origins (i.e., seed sources). We evaluated the germination capacity (%) under different matric potentials (i.e., 0, −6, −33, −750 and −1250 kPa) for 100 days. Soil matric potential of −1250 kPa negatively affected the germination capacity of the three species. P. chilensis seeds stopped germinating under soil matric potential close to −1200 kPa, whereas in Q. saponaria and C. alba the complete inhibition of germination was under −1000 kPa. Seed sources also differed in their germination capacity by soil matric potential: northern seed sources of P. chilensis germinated with the lowest soil matric potential. There was no clear trend in Q. saponaria and C. alba, but in general, southern seed sources performed better than the northern ones. The results showed that Ѱ_m in the soil played an important role in the germinative capacity against different seed source origins, but not in soils with a north–south gradient.

Climate change is threatening the restoration efforts in Mediterranean ecosystems, and there is still little knowledge about the responses of some sclerophyllous species to plant management techniques. This study assessed the effects of the planting date, use of mulch, and controlling light levels on the early survival and growth of sclerophyllous species established in island plots. A factorial design was installed in the Metropolitan Region of central Chile, with a treatment combination that included three planting dates (January: midsummer, April: autumn, and June: winter), three light levels (full sun exposed (T0), shaded at 35% (T35), and shaded at 70% (T70)), and two mulch levels (no mulch versus mulch application). Additionally, we tested the species effects within the island plot. We measured survival, as well as plant diameter and height increments, 1 year after establishment. Each island plot contained three seedlings of Acacia caven Mol., two of Quillaja saponaria Mol., two of Maytenus boaria Mol., one of Schinus polygamus (Cav.) Cabrera, and one of Cryptocarya alba (Mol.) Losser. We found a significant main effect for all the factors assessed. Despite the high mortality in the trial, survival was increased around fourfold by planting in winter, using mulch, or using either of the shading levels. At the species level, average survival ranged from 7% for C. alba to 27% for S. polygamous. To increase plant survival in the restoration of this ecosystem, it is necessary to intensify the management techniques and the use of these types of eco-technologies; if not, the restoration may fail.

Quillaja saponaria is a sclerophyllus evergreen tree species distributed from 30° to 38° S in Central Chile. In this wide distribution it is expected that the species exhibits phenotypic plasticity in the morphology of leaves associated to climate variation; however, the information on this topic is still scarce. We studied leaf phenotypic variation and its relationship with temperature, precipitation, and aridity in 85 stands of Q. saponaria throughout the natural distribution of the species. The results show that the basal diameter of petiole, the number of secondary veins, and the basal diameter of the principal vein increased with precipitation and decreased with aridity, while the length, basal diameter and the relative length of the petiole decreased with temperature. This confirms that phenotypic variation for foliar characters in Q. saponaria is related to climatic variables indicating an adapting capability of the species to the wide range of environmental conditions in which grows.