Headwaters drive streamflow and lowland tracer export in a large-scale humid tropical catchment

 

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Detalles Bibliográficos
Autores: Birkel, Christian, Correa, Alicia, Martinez Martinez, Marco, Granados-Bolaños, Sebastián, Venegas Cordero, Nelson, Gutiérrez-García, Kenneth, Blanco-Ramírez, Sara, Quesada-Mora, Rafael, Solano-Rivera, Vanessa, Mussio-Mora, Jasson, Chavarría-Palma, Andrés, Vargas-Arias, Katherine, Moore, Georgianne W., Durán-Quesada, Ana María, Vasquez Morera, Javier, Soulsby, Chris, Tetzlaff, Dorthe, Espinoza-Cisneros, Edgar, Sanchez-Murillo, Ricardo
Formato: artículo
Fecha de Publicación:2020
Descripción:Headwaters are generally assumed to contribute the majority of water to downstream users, but how much water, of what quality and where it is generated are rarely known in the humid tropics. Here, using monthly monitoring in the data scarce (2370 km2) San Carlos catchment in northeastern Costa Rica, we determined runoff-area relationships linked to geochemical and isotope tracers. We established 46 monitoring sites covering the full range of climatic, land use and geological gradients in the catchment. Regression and cluster analysis revealed unique spatial patterns and hydrologically functional landscape units. These units were used for seasonal and annual Bayesian tracer mixing models to assess spatial water source contributions to the outlet. Generally, the Bayesian mixing analysis showed that the chemical and isotopic imprint at the outlet is throughout the year dominated by the adjacent lowland catchments (68 %) with much less tracer influence from the headwaters. However, the headwater catchments contributed the bulk of water and tracers to the outlet during the dry season (>50 %) despite covering less than half of the total catchment area. Additionally, flow volumes seemed to be linearly scaled by area maintaining a link between the headwaters and the outlet particularly during high flows of the rainy season. Stable isotopes indicated mean recharge elevations above the mean catchment altitude, which further supports that headwaters were the primary source of downstream water. Our spatially detailed “snap-shot” sampling enabled a viable alternative source of large-scale hydrological process knowledge in the humid tropics with limited data availability.
País:Repositorio UNA
Institución:Universidad Nacional de Costa Rica
Repositorio:Repositorio UNA
Lenguaje:Inglés
OAI Identifier:oai:null:11056/21227
Acceso en línea:http://hdl.handle.net/11056/21227
Palabra clave:HEADWATER
HUMID TROPICS
TRACERS
STABLE ISOTOPES
BAYESIAN MIXING MODEL
COSTA RICA
ISOTOPOS
TRÓPICO HÚMEDO
CUENCAS HIDROGRÁFICAS