Changes in Climate and Crop Production During the 20th Century in Argentina

Abstract

This work was focused on the assessment of changes occurring in crop production and climate during the 20th century in Argentina. The study was carried out for nine sites located in the Pampas region that are representative of contrasting environments. We have considered the four main crops cultivated in this area (wheat, maize, sunflower and soybean). Historical climatic data and crop production related variables (yield, planted area, harvested area) were analyzed and, by means of crop simulation models, we quantified the impact of climate on crop yields. Changes occurring in climate during the three last decades of the 20th century were characterized by important increases in precipitation especially between October and March, decreases in maximum temperature and solar radiation in particular during spring and summer and increases in minimum temperature during almost all of the year. These changes contributed to increases in yields, especially in summer crops and in the semiarid zone, mostly due to increases in precipitation, although changes in temperature and radiation also affected crop yields but to a lesser extent. Comparing the period 1950Comparing the period -1970Comparing the period with 1971Comparing the period -1999 yields increases attributable to changes in climate were 38% in soybean, 18% in maize, 13% in wheat, and 12% in sunflower while mean observed yield increases were 110% for maize, 56% for wheat and 102% for sunflower.

Resistance and Resilience of A Stream Salamander To Supraseasonal Drought

“…For example, increased annual runoff may produce benefits for a variety of both instream and out-of-stream water users by increasing renewable water resources, but may simultaneously generate harm by increasing flood risk. In recent decades, a trend to wetter conditions in parts of southern South America has increased the area inundated by floods, but has also improved crop yields in the Pampas region of Argentina, and has provided new commercial fishing opportunities (Magrin et al, 2005 Increased precipitation intensity may result in periods of increased turbidity and nutrient and pathogen loadings to surface water sources. The water utility serving New York City has identified heavy precipitation events as one of its major climate-change-related concerns because such events can raise turbidity levels in some of the city's main reservoirs up to 100 times the legal limit for source quality at the utility's intake, requiring substantial additional treatment and monitoring costs (Miller and Yates, 2006).…”

Distribución y variabilidad de la precipitación en la Región Pampeana, Argentina

“…Su impacto se expresa en la variación del rendimiento entre períodos pasados y escenarios climáticos futuros (Magrin et al, 2005). El área de estudio se ve afectada por periódicas inundaciones que afectan a las áreas rurales (sembrados, hacienda y viviendas) y zonas urbanas.…”

“…El aumento de precipitaciones registrado en la Región Pampeana ocasionó notables incrementos en los rendimientos de los cultivos de secano (Magrin et al, 2005) y contribuyó de forma contundente a la expansión de las fronteras agrícolas y del área sembrada con cultivos anuales (Volante et al, 2015). Como evidencia de esto se observó un desplazamiento de la isohieta de 500 mm hacia el oeste durante la década de 1990, la cual constituye el límite occidental de la Región Pampeana, permitiendo la expansión de cultivos de grano (Sierra et al, 1994).…”

Trends of Soybean Yields under Climate Change Scenarios

“…In this region, the agricultural landscape has faced major changes during the last 30 years due to new technologies for crops, to a strong increase in cereal and oil crop world demands, and also to favorable climate conditions with increases of about 20%-30% in annual precipitation over large parts of the region [8].…”