HomeReportsSubglobal AssessmentsArgentina (Pampas)

Argentina

The provision of ecosystem services and human well-being in the Pampas of Argentina

Contact Information

  • Dr. Ernesto F. Viglizzo
    INTA Centro Regional La Pampa
    Av. Spinetto 785 (C.C. 302), 6300 Santa Rosa
    La Pampa, Argentina
    evigliz@cpenet.com.ar

Project Team and Institutions

  • Ernesto F. Viglizzo (INTA Argentina)
  • Emilio Satorre (Buenos Aires University)
  • Otto T. Solbrig (Harvard University, USA)
  • Filemón Torres (CEO Consultants)
  • Jorges Ingaramo (Cereals Board of Buenos Aires).

Timeframe

The assessment of condition and trends extends from 1880 to 2000, but detailed information is provided only for the period 1960–2000. Scenarios are projected to the year 2025.

Funding

This assessment was funded by the National Institute for Agricultural Technology (INTA) of Argentina.

Main Findings

The assessment looks at four increasing geographical scales (farm, major agroecosystems, the whole Pampas, and the Del Plata basin) and time periods (from one year to four decades). Some findings in relation to the supply of ecosystem services and their impact on human well-being in the Pampas are the following:

  • Food production: Since the beginning of colonization (1879), the Pampas of Argentina have shown their ecological potential for food production at a commercial scale. Crop and beef productivity have been growing steadily at increasing rates, and this has resulted in increased surpluses to fulfill domestic and export needs. Today, the dynamics of Argentina’s economy strongly depend on the Pampas’ provisioning and underlying ecosystem services. Current production is still far from the biophysical potential of ecosystems, and there is enough room to increase productivity through (1) the conversion of natural and cultivated grazing lands into croplands, and (2) increased use of external inputs. We expect that the profile of the Argentine Pampas as an international food supplier will be confirmed in coming decades and the Pampas will have an increasing economic impact at the regional, the national, and the Del Plata basin scales.
  • Soil erosion control and carbon sequestration capacity: Since the end of the nineteenth century, land use conversion for increasing food production has deteriorated the capacity of ecosystems to control soil erosion and sequester atmospheric carbon in soil and vegetation. Considering that these ecosystem services are coupled, they have been affected by similar changing factors. The persistent conversion of natural grasslands into cultivated lands, the extensive use of fire for managing rangelands and grasslands, the introduction of ruminant grazing cattle, and the spreading of non-conservative tillage operations for more than 80 years, have triggered frequent soil erosion episodes and transformed a carbon sequestering region into a carbon-emitting one. Soil erosion has a broader scale, off-site impact (water sedimentation) on the Del Plata basin mouth. Carbon emission from the Pampas has, on the other hand, impact on atmospheric warming at a global scale but which has not been fully assessed. In recent times, declines in both these services have stopped and even been slightly reversed due to the extensive application of no-tillage practices. These practices are driving both a re-accumulation of soil organic carbon and a drastic reduction in fossil fuel consumption.
  • Freshwater provision: In quantitative terms, freshwater provision is not a limiting factor for human well-being in the Pampas. However, the increasing utilization of chemical inputs (especially pesticides and fertilizers) due to the expansion of the cropping area is probably affecting water quality in various areas of the region. Our regional scale studies using models tend to demonstrate that the risk of water contamination is increasing in areas where continuous cropping predominates. These estimations are confirmed by non-point field measurements over recently converted lands. Because of multiple surface and groundwater connections, contamination at the farm scale spreads to broader scales.
  • Habitat provision: All over the region, the expansion of cultivation is causing rapid simplification of the rural landscape, especially in continuously cropped lands. Although the systematic assessment of biodiversity is still uncommon in the Pampas, the fragmentation of landscapes, the utilization of conventional tillage, and the application of pesticides have all been consistent causes of decline in habitat provisioning. Thus we can presume that wildlife biodiversity is persistently declining over the whole region, but particularly in the more intensively impacted ecosystems.
  • Nutrient cycling: The replacement of rangelands and cultivated grasslands by croplands is deeply modifying the nutrient cycling in ecosystems. Our studies have revealed an increasing weakness of organic compartments in nitrogen (N) and phosphorus (P) cycles. The retention of N and P in strong organic compartments has maintained a robust functioning of nutrient cycles when rangelands and legume-based cultivated grasslands have predominated over croplands. The expansion of croplands during the last 20 years has caused rapid depletion of the soil nutrient endowment and a growing use of inorganic fertilizers (especially N) to compensate for this. Increased leakage of nutrients and the risk of water contamination were unavoidable results. On-site actions affecting nutrient cycles have off-site effects at wider scales. Thus the disruption of nutrient cycles not only affects the on-site maintenance of soil fertility, but also puts at risk the off-site provisioning of good-quality fresh water.

References

  • Bernardos , J.N., E.F. Viglizzo, V. Jouvet, F.A. Lértora, A.J. Pordomingo, and F.D. Cid, 2001: The use of EPIC model to study the agroecological change during 93 years of farming transformation in the Argentine pampas. Agricultural Systems 69/3, 215–234.
  • Viglizzo , E.F., A.J. Pordomingo, M.G. Castro, and F.A. Lértora, 2003: Environmental assessment of agriculture at a regional scale in the Pampas of Argentina. Environmental Monitoring and Assessment 87, 169–195.
© 2005 Millennium Ecosystem Assessment