Sao Paulo Agronomy Institute tests soils to plant soy, sunflowers, peanuts and other oil crops in rotation with sugarcane.
Credit: Nilson Konrad
Brazil in Search of Sustainable Ethanol
By Roberto Villar Belmonte
Limiting the areas where sugarcane can be planted, reducing cane field burn-offs, and promoting direct planting are some of the efforts to counter the environmental damages of Brazil's ethanol boom.
PORTO ALEGRE, Brazil, Jul 23 (Tierramérica).- To minimize international criticism of its cane alcohol industry, the Brazilian government announced that it will ban new sugarcane fields in the Amazon region and in the vast Pantanal wetland.
In addition, researchers and farmers are working to eliminate burning of fields and promote the collection of raw cane, direct planting and rotating sugarcane with food crops in response to the main fears awakened by the possibility of unregulated expansion of sugarcane production.
Following the release earlier this year of new scientific data about the grave effects of climate change -- caused in large part by emissions from burning fossil fuels -- ethanol or fuel alcohol has come to be seen as a viable alternative for reducing gasoline consumption, because its combustion produces less greenhouse-effect gases.
This more eco-friendly attribute of the fuel accelerated the boom in Brazil's alcohol industry, but gave footing to other environmental concerns, voiced emphatically by President Fidel Castro of Cuba and President Hugo Chávez of Venezuela.
The burning of cane fields to get rid of the leaves is common practice, and produces nearly 4,500 kilograms of carbon dioxide per hectare.
Another fear is that new cane fields would occupy areas otherwise destined for food crops, as has occurred in recent years in the Monte Azul area, in the north of Sao Paulo state, a long-time producer of oranges, where orchards are being replaced by sugarcane.
The possibility of the sugarcane industry increasing deforestation of the Amazon is also keeping environmentalists on their guard.
In part to head off those arguments, Brazil's Ministry of Agriculture announced on Jul. 17 that it will ban sugarcane encroachment in the Amazon and the Pantanal, a vast wetland in the west of the country that extends into Paraguay and Bolivia. The ban will take effect through a territorial registry of the areas in which new crops can be planted, and is to be ready within a year.
The purpose is to provide incentives for sugarcane expansion in agricultural areas already degraded by use as pastures. Another measure announced is the social and environmental certification of the entire sugar production chain, an effort involving experts from the Brazilian agricultural research agency, EMBRAPA, and soon to be put up for discussion with the sugar industry's leaders.
"The expansion of sugarcane in Sao Paulo is already occurring, especially in pasture areas... There is no reason to take over forests, because this country has plenty of degraded land available," Marcos Landell, director of the Sugarcane Agronomy Institute (IAC), told Tierramérica.
A study by IAC, associated with the government of Sao Paulo state, shows that in the last 30 years production levels jumped from 65 to 90 tons of sugarcane per hectare. The number of harvests grew from three to six per year, which increased the sector's environmental impacts.
Also on the rise is the mechanical collection of raw cane. In this way, the leaves are not burned off and instead fall to the ground to decompose as natural fertilizer. According to Landell, in some areas there are up to 20 tons of stubble per hectare per year, which represents a huge return of organic material for the tropical soils.
Sugarcane today covers seven million hectares in Brazil, four million in Sao Paulo state alone. With the production level of 30 years ago, twice the area would be needed to obtain the same amount of alcohol produced today, or about 7,000 liters per hectare. The experts hope to push it further, to 11,000 liters per hectare in the next few years by using genetic and industrial improvements.
In 15 years more, the increase in yields across the system should be 80 percent. "In this way, the planted area would not surpass 30 million hectares," says Landell.
Improvements over the past decade allowed cultivation of more than 80 types of sugarcane, "the crop with the greatest number of varieties on each farm. This diversity creates resistance and helps protect the plants from diseases," he explained.
As a result, less pesticide is used. The new varieties are resistant to many of the diseases that tend to affect cane fields.
According to the IAC, the advance of sugarcane could even promote production of food. Fifteen percent of the country's cane fields are available each year for rotation with crops to help renew the soils, which represents millions of hectares for growing soybeans, peanuts and other crops.
In the Sao Paulo region of Ribeirao Preto, direct planting -- without tilling or removing waste from previous crops -- is increasingly being used for renewing cane fields. Cane farmers cultivate and harvest fast-growing varieties of soybean and peanut in the stubble left from cane before beginning a new sugarcane cycle.
On some farms, the new cane is planted among the stubble of the harvested legumes. "This is an irreversible trend," says Landell.
Direct planting without burning off cane leaves is a practice that can be adopted in all sugarcane-growing regions across Brazil, according to the Sao Paulo Agribusiness Technology Agency (APTA).
An estimated one ton of carbon dioxide is captured per hectare of raw sugarcane harvested.
"When the collection of raw cane is collected -- whose biowaste increases the moisture and fertility of the soil -- is combined with direct planting, the environmental benefits are reinforced," APTA researcher Denizart Bolonhezi told Tierramérica.
In Ribeirao Preto, there are 40,000 hectares of peanut cultivated using direct planting and traditional techniques in sugarcane renewal areas. Two cooperatives, Coopercana, in Sertaozinho, and Coplana, in Guariba, collect and sell the peanuts.
"With current technology, we can reconcile production of food with production of sugarcane" for ethanol, says Bolonhezi.
Brazil's advances in this area means that the expansion of fuel alcohol can be sustainable, say its promoters.
It remains to be seen whether the government will be able to establish production standards that are environmentally friendly and, above all, if it will be able to monitor the new areas planted, which Brasilia is promoting in search of more ecological sources of energy than fossil fuels.
* Roberto Villar Belmonte is a Tierramérica contributor.