Agricultural Drought Phenomenon in Latin America with Focus on Brazil - Monitoring and Predicting Agricultural Drought: A Global Study - page 166

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D rought Mitigation and Drought Research Needs
No large-scale measures have been adopted to mitigate droughts in Latin
America. The majority of the governmental agencies act on a post-facto
circumstances seeking to minimize the social effects of the drought phe-
nomenon. Nevertheless, the following measures are taken to mitigate
droughts.

C limatic Risk Zoning

The climatic risk zoning defines the best sowing period for each crop to
reduce the risk of drought. This approach is being developed for all of
Brazil and is coordinated by the agricultural ministry (Assad, 2001). Before
the implementation of this zoning, the agricultural losses due to droughts
were as high as 30%, but currently the loss is reduced to under 2% in
the areas where the approach was implemented. There is also a need to
develop better irrigation techniques to further improve water-use efficiency
and drought mitigation.

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Be tter Planting Techniques

The use of appropriate agronomic techniques, ranging from soil manage-
ment to crop selection, can help ensure survival of plant species leading to
reasonable production. In the state of S ao Paulo, direct planting of maize
and wheat is better than the conventional planting to withstand drought
conditions, because the direct planting allows for better establishment of
plants under the conditions of up to 45 days without rainfall (Cunha,
1999). It was also observed that the use of a drought-tolerant variety of
maize increased the yield and resistance to drought conditions. Further re-
search needs to be conducted to evaluate planting systems that allow the
root system of plants to grow deeper and exploit a larger soil volume to
mitigate impacts of droughts.

[166

C onclusions
There is a wide variation in climatic conditions in South American coun-
tries. ENSO activities cause droughts in some regions. There is a need to
strengthen relationship between ENSO activities and drought occurrence.
Better models need to be developed by combining ENSO data, drought in-
dices, and satellite data for monitoring and predicting agricultural droughts
more effectively across South America.

Re ferences
Alfonsi, R.R., H.S. Pinto, and H.V. Arruda. 1979. Freqüência de verânicos (dry
spell) em regi oes rizícolas do Estado de S ao Paulo. Proceedings Reuni ao de