Food and floods. Shallow groundwater and agricultural land management in the Pampas

This fact sheet examines the relationship between land use, shallow groundwater levels, and flooding in the Argentinean Pampas. It highlights how the shift from perennial alfalfa pastures to annual grain rotations has increased flooding frequency and suggests that planting water-logging tolerant cover crops can mitigate these risks.

• The transition from perennial alfalfa pastures to annual wheat-soybean-maize rotations has led to higher groundwater levels and a significant increase in flooding events. Pastures maintain average groundwater tables at -4.4 meters and result in 2 flooding events over a 100-year simulation, whereas annual crops maintain tables at -2 meters and result in 47 flooding events.
• Cyclic flooding in the Pampas affects 16 million hectares of land. A specific flood event between 1997 and 2003 covered 27% of the western Pampas, driven by average groundwater levels rising 2.3 meters, which caused significant economic losses.
• Land use is a critical driver of flooding because different plants have different water use rates. Annual crop production leaves fields bare for part of the year, allowing surplus water to accumulate, while deep-rooted, year-round alfalfa keeps soils drier.
• Planting cover crops or pastures that are tolerant to water-logging, such as ryegrass or alfalfa, during high-risk periods can increase the number of years suitable for farming by 40% and reduce the frequency of waterlogging.

APA

Inter-American Institute for Global Change Research (2024). Food and floods. Shallow groundwater and agricultural land management in the Pampas. https://iai.int/en/alimentos-e-inundaciones/

Chicago

Inter-American Institute for Global Change Research. Food and floods. Shallow groundwater and agricultural land management in the Pampas. 2024. https://iai.int/en/alimentos-e-inundaciones/.

Wikipedia

{{cite report |author=Inter-American Institute for Global Change Research |title=Food and floods. Shallow groundwater and agricultural land management in the Pampas |date=8 October 2024 |url=https://iai.int/en/alimentos-e-inundaciones/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{interamericaninstituteforglobalchangeresearch2024food, author = {{Inter-American Institute for Global Change Research}}, title = {{Food and floods. Shallow groundwater and agricultural land management in the Pampas}}, institution = {Inter-American Institute for Global Change Research}, year = {2024}, month = oct, url = {https://iai.int/en/alimentos-e-inundaciones/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }