Carbon and water footprints in Brazilian coffee plantations - the spatial and temporal distribution

The future of many coffee growing regions, such as Brazil, depends on strategies to allow the minimization of the negative impacts of climate change. Still the own contribution of coffee cultivation for global warming is largely unknown. Water and carbon footprints are concepts that indicate the potential negative impact of a specific product, underlining which part of the process is the major responsible for it. In this context, the objective of this study was to quantify and spatialize the water and carbon footprints from coffee crop in different regions of Brazil, and to find the proportional weight of coffee production in the total emission of CO2 and water consumption in the context of Brazilian agriculture. For this end, water and carbon footprints were estimated and spatialized for Brazilian regions along 10 productive seasons (from 2004/2005 to 2014/2015), based on data of plantation area (ha) and coffee production (tons of beans). It is concluded that the estimates of annual carbon and water footprints were 19.791 million t CO2-equivalent and 49,284 million m3 of water, with higher values from the Southeast region. This corresponded to a moderate (ca. 5%) value for the emissions of greenhouse gases, but a relevant water footprint in the context of Brazilian agricultureinfo:eu-repo/semantics/publishedVersio

Magnetism of atomically thin fcc Fe overlayers on an expanded fcc lattice: Cu84Al16(100)

We present experimental data on the magnetic properties of atomically thin fcc (γ-phase) Fe films (1-6 atomic layer nominal thickness) epitaxially grown on (Formula presented) obtained by linear magnetic dichroism in the angular distribution of Fe (Formula presented) core photoelectrons excited by linearly polarized synchrotron radiation. The sign and magnitude of the Fe (Formula presented) photoemission magnetic asymmetry indicates the onset of in-plane ferromagnetism at 2.5(2) monolayer (ML) thickness of γ-Fe. The Curie temperature is 288(2) K for 4 ML thickness. The magnetic splitting of the Fe (Formula presented) core hole sublevels is 1.10(2) eV, i.e., the same value as measured for a bcc-Fe(100) surface where large surface and near-surface enhanced moments contribute. These results characterize the epitaxial γ-Fe on (Formula presented) as a high-spin ferromagnet for thickness up to 4 ML, with an average magnetic moment per iron atom of 2.5(1)(Formula presented) A phase transition occurs between 4 and 5 ML thickness: the magnetic order of the pseudomorphic γ-Fe film decreases consistently with the breaking into two phases with the deeper layers in a low-spin and/or antiferromagnetic phase and surface restricted ferromagnetism, similar to the case of γ-Fe/Cu(100). © 1998 The American Physical Society