RESUMEN
This study compared the environmental burdens of two broiler chicken production systems in Brazil and two in France. One Brazilian system represents large-scale production in the Center-West region of the country; the other is a small-scale production in the South. One of the French systems represents an extensive broiler chicken production system, known as "Label Rouge"; the other is a standard system. Life-cycle impact assessments were performed using the CML-IA characterization method. The main functional unit adopted was 1 tonne of cooled and packaged chicken, ready for distribution. For the systems and impacts studied, production scale did not affect the environmental impact, but production intensity did. The extensive Label Rouge system had the largest impact among the impact categories studied. This resulted principally from the high feed-conversion ratio of this production system (3.1 kg of feed per kg of live weight) in conjunction with the fact that the feed-production stage contributed most to the overall impact. The contribution of deforestation to the crop-production stage was significant, particularly for climate change, equaling 19% of total emissions of CO2eq per tonne of cooled and packaged chicken, in the system of the Center-West of Brazil. The French systems were also affected, since they import crops from Brazil. The system of southern Brazil had less climate change impact because there is no longer deforestation in southern Brazil for crop production.
Asunto(s)
Ambiente , Productos Avícolas , Animales , Brasil , Pollos , FranciaRESUMEN
Soybean production and its supply chain are highly dependent on inputs such as land, fertilizer, fuel, machines, pesticides and electricity. The expansion of this crop in Brazil in recent decades has generated concerns about its environmental impacts. To assess these impacts, two representative chains supplying soybeans to Europe were identified: Center West (CW) and Southern (SO) Brazil. Each supply chain was analyzed using Life Cycle Assessment methodology. We considered different levels of use of chemical and organic fertilizers, pesticides and machinery, different distances for transportation of inputs and different yield levels. Because transportation contributed strongly to environmental impacts, a detailed study was performed to identify the routes used to transport soybeans to seaports. Additionally, we considered different levels of land occupation and land transformation to represent the impact of deforestation in the CW region. Environmental impacts were calculated for 1000 kg of soybean up to and including the delivery to Europe at the seaport in Rotterdam, at 13% humidity. Overall results showed that the impacts are greater for CW than for SO for all impact categories studied, including acidification (7.7 and 5.3 kg SO(2) eq., respectively), climate change (959 and 510 kg CO(2) eq.), cumulative energy demand (12,634 and 6,999 MJ) and terrestrial ecotoxicity (4.9 and 3.1 kg 1,4-DCB eq.), except eutrophication and land occupation. The same trend was observed for the crop-production stage. Efforts to reduce chemical fertilizers and diesel consumption can reduce CO(2) emissions. Although deforestation for crop production has decreased in recent years, the contribution of deforestation to climate change and cumulative energy demand remains significant. In the CW scenario deforestation contributed 29% to climate change and 20% to cumulative energy demand. Results also showed that although there are different transportation options in Brazil, the current predominance of road transport causes severe environmental impacts. In CW, road transport contributed 19% to climate change and 24% to cumulative energy demand, while in SO it contributed 12% and 15% to these impacts, respectively. Improvements in the logistics of transportation, giving priority to rail and river transports over road transport, can contribute significantly to reducing greenhouse gas emissions and decreasing energy use. Future studies involving Brazilian soybeans should take into account the region of origin as different levels of environmental impact are predicted.