Water Appropriation on the Agricultural Frontier in Western Bahia and Its Contribution to Streamflow Reduction: Revisiting the Debate in the Brazilian Cerrado

Autor: Ludivine Eloy, Yuri Botelho Salmona, Andrea Leme da Silva, Saulo Aires de Souza, Osmar Coelho Filho, Carlos José Sousa Passos
Přispěvatelé: University of Brasilia [Brazil] (UnB), Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Université de Perpignan Via Domitia (UPVD)-Université Paul-Valéry - Montpellier 3 (UPVM)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
lcsh:Hydraulic engineering
010504 meteorology & atmospheric sciences
water appropriation
Geography
Planning and Development

0207 environmental engineering
Drainage basin
02 engineering and technology
Aquatic Science
Structural basin
01 natural sciences
Biochemistry
Tropical savanna climate
lcsh:Water supply for domestic and industrial purposes
Brazilian Cerrado
lcsh:TC1-978
western Bahia
Streamflow
Precipitation
smallholder communities
Water cycle
[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology
020701 environmental engineering
0105 earth and related environmental sciences
Water Science and Technology
Hydrology
geography
lcsh:TD201-500
geography.geographical_feature_category
hydrology analysis
[SHS.GEO]Humanities and Social Sciences/Geography
15. Life on land
[SDE.ES]Environmental Sciences/Environmental and Society
6. Clean water
Water resources
13. Climate action
agribusiness
Corrente River basin
Surface runoff
Zdroj: Water
Volume 13
Issue 8
Water, MDPI, 2021, 13 (8), pp.1056. ⟨10.3390/w13081054⟩
Water, Vol 13, Iss 1054, p 1054 (2021)
ISSN: 2073-4441
DOI: 10.3390/w13081054
Popis: Over the last three decades, almost half of the Brazilian tropical savanna (Cerrado biome) has been converted into cropland and planted pastures. This study aims to understand the implications of the expansion of the agricultural frontier for water resources in western Bahia state. We use an interdisciplinary approach that combines quantitative and qualitative data (spatial and hydrological analysis, interviews) to tie together land use changes in the Corrente basin, the streamflow and precipitation time series in the Pratudão River sub-basin (part of the Corrente basin), and the perceptions of soybean farmers and smallholder communities about the transformations of the hydrological cycle over the last few years. We observed an almost 10-fold increase in agricultural surface area in the Corrente River basin over the last three decades (1986–2018), going on from 57,090 ha to 565,084 ha, while center-pivot irrigated areas increased from 240 ha to 43,631 ha. Over this period, the streamflow has reduced by 38% in the Pratudão River. Our hydrological analyses, based on the Mann-Kendall test, of seven fluviometric stations and 14 pluviometry stations showed a statistically significant streamflow trend in the Pratudão River sub-basin for both minimum and mean streamflow series (p ≤0.05). Surface runoff coefficient, which relates streamflow and precipitation annual data coefficient, decreased from around 0.4 in the late 1990s to less than 0.2 in 2015. In addition, most precipitation time series analysis (number of annual rainy days) showed no statistically significant trend (p >
0.05). Our results indicate that agricultural changes rather than climate change may be the main driver of downward streamflow trends in the Pratudão River sub-basin that is part of Corrente River basin.
Databáze: OpenAIRE