Assessing potential impacts of sugarcane production on water resources: A case study in Brazil

Abstract

Sustainability has been considered essential for the future consumption of biofuels in large scale and, thus, assessing the impacts on water resources is one of the priorities. The aim of this study is to assess the potential impacts of sugarcane expansion both on the quality and on the quantity of water resources, but using a publicly available database and well‐established statistic procedures. The case studies were defined in São Paulo state, where the bulk of sugarcane production in Brazil is, and more specifically three regions where significant expansion recently occurred: Palmares Paulista, Pontal, and Ribeirão Preto. Time series of streamflows and precipitations (1974–2011) and water quality parameters (1989–2011) were evaluated using non‐parametric tests for detecting trends and abrupt changes. Quality parameters analyzed were concentrations of potassium, total phosphorus, nitrite, nitrate, ammoniacal nitrogen, total solids, dissolved oxygen, and biochemical oxygen demand. Sugarcane cropping data were correlated with streamflows and water quality parameters. Water quality parameters were analyzed vis‐à‐vis sugarcane production and population growth. Significant impacts due to sugarcane cropping were detected only in the case of the smallest basin. In the three studied regions a significant increasing trend of nitrogen and biochemical oxygen demand was observed, but these results can be explained either by sugarcane–ethanol production or by the discharge of sewage and industrial effluents without appropriate treatment. Based on data availability it was not possible to rigorously determine the contribution of large‐scale production of sugarcane cropping to both the quantity and the quality of water resources. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

Hydrological trade-offs due to different land covers and land uses in the Brazilian Cerrado

“…Changes in the LCLU, such as the potential conversion from wooded Cerrado to an agricultural LCLU (here we tested the pasture), may affect groundwater recharge, processes and availability. These effects tend to be non-linear and difficult to analyze as they result from complex interactions between LCLU and hydrological processes (Han et al, 2017). Thus, mathematical approaches (Archer and Fowler, 2018;Gómez et al, 2018) or natural tracers (Su et al, 2018) are useful tools for verifying the response time of the groundwater table to the water balance from different LCLU types.…”

The Sustainability of Sugarcane Ethanol in Brazil: Perspective and Challenges

“…Further, water withdrawal was significantly reduced by sugarcane mills, from 5.6 m 3 t −1 to 1.5 m 3 t −1 between 1990 and 2008. Thus, these elements has shown that sugarcane is an agricultural activity more efficient than others in terms of the use of water resources, with the main cropped land using, in general, rainfall as the water resource in the field [13,24,25].…”