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The potential for sugarcane ethanol from Brazil to mitigate GHG emissions is undeniable, but the way that ethanol is produced during the agricultural and industrial phases will ultimately determine its benefits to society. In this paper, we evaluate the environmental impacts of sugarcane agriculture and ethanol production in Brazil as management practices continue to change and production expands to new frontiers. We focused our evaluation on the impacts on water, atmosphere, and soils, including how the application of organic and inorganic fertilizers and the accumulation of crop residue in the field affect emissions of greenhouse gases (GHG). We also addressed the impacts of land use changes on threatened biomes and discussed some of the present obstacles regarding conservation and restoration efforts. We concluded that, since a similar assessment was put forth in 2008, our knowledge about the environmental impacts of sugarcane ethanol in Brazil has advanced with regard to soil degradation, nitrogen dynamics, and soil carbon stocks. However, more information is still needed about the impacts of the increasing use of pesticides, herbicides, and fertilizers in sugarcane agriculture, especially on water resources. Furthermore, without a better understanding about how landscape fragmentation affects the biodiversity of terrestrial and aquatic tropical ecosystems and the services they provide, policies created to protect and restore them may be ineffective. On the other hand, the use of presently available scientific information to end unsustainable farming and the implementation of conservation strategies proposed by the Brazilian Forest Code could be a first step to guarantee that ethanol is produced more sustainably in Brazil.

The carbon stable isotope ratio (δ13C) has become an important tool to determine the composition and quality of various beverages, indicating the amount of C3- and C4-sources used in brewing. Accordingly, we assessed the isotopic composition of beers produced in Brazil and abroad, in order to quantify the use of C4-sources as adjuncts. We also related the presence of such adjuncts to beer price, and compared the current results to similar studies, in order to assess any differences regarding beer composition over time. The mean δ13C value for Brazilian beers was around −22.0‰, indicating a high addition of C4-adjuncts during the brewing process. A dichotomy of beer isotopic signatures was observed: beers from large breweries had higher δ13C values (around −20.0‰) than beer from artisanal breweries (−25.0‰). Beer price per L was directly related to δ13C values in Brazil and abroad. This significant relationship, in addition to the 13C-enrichment observed in this study, may reflect a change in the Brazilian beer market, in which a greater variety of beverages are produced and marketed following traditional recipes regarding their purity.

Brazil has emerged in this century as a powerhouse, developing a high productivity tropical agriculture, and today is one of the key players in the global food system. However, such increase of Brazilian agriculture was not without costs. One of the most important consequences was the loss of original vegetation and all the ecosystem services linked to this loss. Most of the Atlantic Forest was converted in urban or agricultural areas; approximately half of the Cerrado was also already converted, and more than 15 % of the Amazon forest was also lost. Coupled with loss of vegetation there is also environmental problems linked to agricultural practices such as: burning and heavy use of pesticides, and to a lesser extent of mineral fertilizers. However, the decoupling of agriculture production and deforestation observed in several regions of the country give us hope that in the future agriculture could advance without further vegetation loss. This mean that intensification will take place, and such has to be conducted under the umbrella of what is called “sustainable agriculture”, which in turn is a series of practices aimed to give to an agroecosystem more complexity in order to mimic natural ecosystems. Among these practices several of them have already been adopted in large scale in the country, especially no-till, crop rotation, and lately crop-livestock systems. If Brazil succeeds in overcoming this challenge, it will not only benefit itself, but also other tropical countries that are pursuing such sustainability and, ultimately the entire world, given Brazil's importance in the global food system.