Hydrological changes in a plain basin in central Argentina following expansion of rainfed agriculture and climate change

GUERRA, JUAN CARLOS; NOSETTO, MARCELO DANIEL

ECOHYDROLOGY

JOHN WILEY & SONS INC

Lugar: New York; Año: 2024

1936-0584

The characterization of long-term streamflow in regions undergoing climatic change and agricultural expansion is relevant for achieving sustainable development goals and for assessing the vulnerability of water-dependent populations and agricultural activities. The objective of this work was to characterize the temporal patterns of water yield in the plain basin of the Carcarañá River (33,063 km2), located in central Argentina and to analyse its relationship with a fast expansion of rainfed cultivation and climate change. The streamflow data for the period 1980–2020 were analysed in conjunction with climatic data (rainfall, reference evapotranspiration), satellite data (NDVI) and cropping statistics (sown area of summer crops) data. The annual water yield averaged ~10% of the rainfall and showed a clear upward trend throughout the study period, both in absolute terms and relative to rainfall (i.e., runoff coefficient), which was not explained by rainfall or reference evapotranspiration temporal patterns. Conversely, we found that the trend in water yield was positively associated with the agricultural area (p