4 pages, 2 tables, This work also acknowledges to ANID/FONDAP No. 1511009; to the Severo Ochoa Centre of Excellence accreditation (CEX2024-001494-S), funded by AEI 10.13039/501100011033, and to the project Highlands.3 from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 872328, Projects: UCV2095, Centro de Acción Climática-PUCV, DI emergent 039.340/2021 PUCV and IAEA project CRPF33031. Celine L. was funded by the projects ANID InES I + D 2021 grant number INID210013 and Marie Curie Postdoctoral Fellowship HORIZON-MSCA-2022-PF-01 project grant number 101106387, Table S1. WS: water source; SPA: sample point altitude in m. asl; MCA: mean catchment altitude in m. asl; CA: catchment area in Km2; EC: electrical conductivity in µs cm−1; Ca: calcium; Mg: magnesium; Na: sodium; K: potassium; HCO3: bicarbonates; Cl: chlorides; SO4: sulphates. All the ions are expressed in meq L-1.-- Table S2. Social perception survey answers. A: perception of the major origin of water during drought years; B: perception of the major origin of water during normal to rainy/snowy years; C: whether they were affected by the megadrought; D: perceptions of the causes of water, Peer reviewed

Table S1. Two-way ANOVA results for physiological analysis of Lessonia spicata during an experiment with control temperatures (15°C) and a treatment (+3°C) for 14 days p<0.05**
Table S2. Two-way ANOVA results for biochemical analysis of Lessonia spicata during an experiment with control temperatures (15°C) and a treatment (+3°C) for 14 days p<0.05**
Table S3. Pearson correlation results for physiological analysis of Lessonia spicata during an experiment with control temperatures (15°C) and a treatment (+3°C) for 14 days p<0.05**
OBJ2, The financial and logistical support were support by the project FONDECYT 11180197, ANID, Chile. The authors acknowledges to supported by the ANID InES GÉNERO [INGE 220004] – ANID and the “Programa de Apoyo para el pago de Procesamiento de Artículos InES Género 2025, Dirección General de Investigación, Universidad de Playa Ancha, Chile”. CNA acknowledges to national doctoral scholarship 21231539 by ANID, Chile. Also, C.L. was supported by the ANID InES I + D 2021 [INID210013], Marie Curie Postdoctoral Fellowship HORIZON-MSCA-2022-PF-01 project [101106387] and the Severo Ochoa Centre of Excellence accreditation [CEX2019-000928-S] funded by AEI 10.13039/501100011033, Peer reviewed

This work was supported by the ANID FONDECYT 1240365 project granted to C.A.S. Also, by the Regional Government of Valparaíso through the FIC (BIP 40046077) and the Chilean National Agency for Research and Development (ANID) InES I+D (INID210013) allocated to C.A.S. V.M. was funded by the ANID COPAS Coastal project (FB210021) and ANID FONDECYT 1211977. C.L. was funded by the Marie Skłodowska-Curie Postdoctoral Fellowship (101106387) and the EU-ANID ECOS-Sud project (ECOS210007). M.G.L. was supported by ANID FONDECYT (1220962). M.J.D. was funded by ANID FONDECYT (3240391). I.S. was funded by ANID FONDECYT 3240401. S.C.L. was funded by the ANID National Doctoral Scholarship Program (No. 21220676/2022) and the ANID COPAS Coastal project (FB210021). B.P. was funded by the ANID National Doctoral Scholarship Program (No. 21262398/2026). B.P. and D.G. were also sponsored by the University of Playa Ancha’s UPLA 24991 Strengthening Project. We finally acknowledge partial contribution of the program for support of article processing charges by project InES Género 2026, Dirección General de Investigación, University of Playa Ancha, This work contributes to the Institut de Ciències del Mar "Severo Ochoa Centre of Excellence" accreditation CEX2024-001494-S funded by AEI 10.13039/501100011033 of the Spanish Ministry of Science and Innovation, Peer reviewed