Social relevance of glaciers water supply in the Central Andes (~33ºS)

Abstract ID: 3.11591 | Not reviewed | Requested as: Talk | TBA | TBA

Sebastián Andrés Crespo (1)
Justinne, Rybertt Goldammer (3); Tomás, Palmisano (4); Celine, Lavergne (5, 6); Andrés, Lo Vecchio (2, 7); Luis, Muñoz Gaete (3); Francisco, Fernandoy (3); Yuliya, Vystavna (8)

(1) conicet, Adrian Ruiz Leal s/n, 5500 Mendoza, AR
(2) Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales, CCT-Mendoza CONICET, Universidad Nacional de Cuyo (UNCuyo), Gobierno de Mendoza, Ruiz Leal s/n, 5500, Mendoza, Argentina
(3) Laboratorio de Análisis Isotópico (LAI), Facultad de Ingeniería, Universidad Andrés Bello, Quillota 980, 2531015, Viña del Mar, Chile
(4) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) / Instituto de Investigaciones Gino Germani, Universidad de Buenos Aires, Pres. José Evaristo Uriburu 950, C1114 AAD, Cdad. Autónoma de Buenos Aires, Argentina
(5) Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar (ICM), Consejo Superior de Investigaciones Científicas (CSIC), Consejo Superior de Investigaciones Científicas (CSIC), 08003 Barcelona, Spain
(6) HUB Ambiental UPLA and Departamento Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Playa Ancha 850, 2340000, Valparaíso, Chile
(7) Laboratorio de Geografía Física y Geotecnologías, Universidad Nacional de Cuyo, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina
(8) International Atomic Energy Agency, Isotope Hydrology Section, Vienna International Centre, Wagramer Str. 5, 1220, Wien, Austria

Categories: Cryo- & Hydrosphere, Hazards, Low-to-no-snow, Sustainable Development, Water Resources
Keywords: rock glaciers, social perception, sustainable water governance, water scarcity, stable isotopes

Categories: Cryo- & Hydrosphere, Hazards, Low-to-no-snow, Sustainable Development, Water Resources
Keywords: rock glaciers, social perception, sustainable water governance, water scarcity, stable isotopes

Abstract

The Putaendo watershed (Central Andes, Chile) was home of pre-colonial inhabitants and the first Chilean town to achieve independence from the Spanish Empire in 1817. Besides its deep socio-historical heritage, this valley has special hydrologic features. It is one of the few examples in the Andes Cordillera where the inhabitants almost entirely rely on the water supply from the periglacial environment in a place with simple winter precipitation regime. This climatic feature, crucial for the discrimination of meltwater inputs when using natural water tracers, allowed us to clearly characterize and quantify the water inputs separately from precipitation using physicochemical analysis. This valley has severely suffered the effects of the mega-drought since 2010, which drastically altered the water supply and strained the livelihoods of pastoralists and peasants to the limit. However, despite the deep decrease in precipitation recorded during the megadrought, the water continued flowing from the headwaters to the Putaendo River. To understand the origin of water, we quantified the contribution of different water sources (snow, rock glaciers and groundwater) in the basin by applying stable water isotopes and major ions. Additionally, a social perception study was carried out to comprehensively understand the popular knowledge regarding the water origin, the impact of the megadrought, climate change and potential mega-mining projects, as the last basin without this activity in the Chilean Central Andes. For an arid water cycle, the river, upstream the Chacrillas dam, results showed a marked predominance of water contributions from rock glaciers at their origin (56%), followed by groundwater (32.8%) and snow (11.2%). The inhabitants of the territory displayed a remarkable awareness and prior knowledge that was manifested when 45.5% of the respondents referred to rock glaciers as the main contributor of water during dry years. There was also a clear negative public opinion regarding the developing of mega-mining projects in the valley (84.1%). The perceptions describe a complex process of social problematization around water scarcity that together with the advanced knowledge on the contribution of the different water sources supply provide key information for regional water security management.