The diffusion of agricultural groundwater extraction in São Paulo, Brazil

Agricultural production in Brazil has increasingly relied on groundwater extraction, raising concerns about the sustainability of underground reservoirs. This paper compares the diffusion of the two most common types of wells used to extract groundwater for agriculture in the state of São Paulo, Brazil: conventional (low depth) and tubular (high depth). We use longitudinal municipal-level information and spatial panel models to analyze the two main drivers of groundwater extractions: climate variability (aridity) and environmental conservation (conservation agriculture and native forest conservation). Our results highlight how increasing aridification in the dry season (winter) has reduced the diffusion of conventional wells and increased the diffusion of less sustainable tubular wells. We also highlight that soil conservation and native forest preservation practices reduce the need for deep underground water extraction.