Production and use of fuel ethanol in Brazil - BAFF

Weed control methods have often been modified due to technological breakthroughs;
in Brazil, sugar-cane crops still use more herbicides than coffee or corn, but less
than citrus crops, and the same as soybean crops. There is a strong trend towards
an increase in areas with crude sugar-cane harvesting, where the straw remains
on the soil. It doesn’t seem possible to totally eliminate herbicides in these cases
for now, as previously expected, especially due to the rise of pests that used to be
unusual.
B3.4.
What is the relative use of fertilizers for sugar-cane
in Brazil and what is the environmental impact of it?
The use of fertilizers in Brazilian agriculture is, for the most part, relative low,
although it has increased over the past thirty years, significantly reducing the need
for new areas.
Of the major crops in Brazil (taking up areas larger than 1 million ha), sugar-cane crops
use less fertilizers than cotton, coffee and orange and an amount equivalent to that of
soybeans. The use of fertilizers is also low compared to that of sugar-cane crops in other
countries (~50 percent more fertilizers in Australia).
The most important factor for that is the recycling of nutrients through the application
of industrial waste (vinasse and filtercake), considering the limiting topography, soil and
environmental control conditions. Substantial increases are observed in the Potassium
content of the soils and in productivity as well. Recycling of nutrients is being optimized
and straw recycling will be very important in expanding areas.
A large number of studies related to leaching and the possibilities of underground
water contamination by vinasse recycling indicate that, for the most part, there are
no harmful impacts for applications of less than 300 m 3 /ha. The Technical Standard
P4.231 issued by CETESB – the environmental protection agency in the State of São
Paulo – under the authority of the State Secretary of the Environment regulates all
relevant aspects of these question.
B. Sugar-cane and ethanol production: environmental aspects
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