CONICET | Buscador de Institutos y Recursos Humanos

Considering uncertainties regarding climate variability, the objective of this study was to make a long-term (1901-2011) comparative assessment of the impact of both land-use decision (changes in the cultivated area) and technology adoption as adaptative mechanisms of the rural sector in the Argentine Chaco and the US Southern Plains. Different sources of data on climate (precipitation, minimum, medium and maximum temperature and evapotranspiration), land-use/land-cover change and technology adoption were used. Methods included: (i) Principal Components Analysis (PCA) was applied to identified the dominant components of data variance, (ii) the relationship between the residuals of precipitation and land-use change was assessed through a simple regression analysis and (iii) technology adoption was assessed through a proxy based on historical changes in the yield of maize (Zea mays L.). The results showed that farmers in both countries relied on two common adaptative strategies to face climate perturbations during the study period: (i) land-use change (a simple binary decision of planting or not planting in response to climate conditions) during a first stage, and (ii) the introduction of adaptative technologies to smooth the impact of climate during the second one. That substitution of adaptive strategies begun during the 1940 decade in the US Southern Plains, and around 30 years later in the Argentine Chaco. The adoption of technologies and agronomic practices explained the sensitivity decay of the cultivated area to the climatic variability during the second stage. The incorporation of improved hybrids with higher drought resistance plus the adoption of tilling practices like minimum tillage or no-till, the input of fertilizers, pesticides and irrigation water (the last one in US, only) became a successful strategy to spread the risk of climate perturbation.