The potential benefits of on-farm mitigation scenarios for reducing multiple pollutant loadings in prioritised agri-environment areas across England

The authors gratefully acknowledge the funding provided by the Department for Environment, Food and Rural Affairs (Defra) via project LM0304

Analysing the agricultural costs and non-market benefits of implementing the Water Framework Directive

Implementation of the Water Framework Directive (WFD) represents a fundamental change in the management of water in Europe with a requirement that member states ensure ‘good ecological status’ for all water bodies by 2015. Agriculture is expected to bear a major share of WFD implementation costs as it is compelled to reduce the emission of diffuse water pollutants. The research outlined here comprises interdisciplinary modelling of agricultural land use, hydrology and consequent water quality effects to consider both agricultural costs and the non-market recreational use (and potentially non-use) values that implementation of the Directive may generate. A theme throughout the research is the spatial distribution of the costs and benefits of WFD implementation, which is addressed through the use of GIS techniques in the modelling of agricultural land use, the integration of land use and hydrological models, and the estimation, aggregation and transfer of the economic value of the benefits

Chemical Heterogeneities on La[subscript 0.6]Sr[subscript 0.4]CoO[subscript 3−δ] Thin Films--Correlations to Cathode Surface Activity and Stability

La[subscript 0.6]Sr[subscript 0.4]CoO[subscript 3−δ](LSC) thin film cathodes synthesized by pulsed laser deposition at 450°C (LSC_450°C) and 650°C (LSC_650°C) exhibit different electrochemical performance. The origin of the differences in the oxygen reduction activity and stability of these cathodes is investigated on the basis of their surface chemistry and their surface atomic and electronic structures. Angle resolved X-ray photoelectron spectroscopy and nanoprobe Auger electron spectroscopy are used to identify the surface cation content, chemical bonding environment, and the spatial heterogeneities with nanoscale resolution. The higher electrochemical activity of LSC_450°C is attributed to the more stoichiometric cation content on the surface and the more uniform lateral and depth distribution of constituent cations. The poorly crystalline atomic structure of the LSC_450°C was found to prohibit the extensive segregation and phase separation on the surface because of the more favorable elastic and electrostatic interactions of Sr in the bulk. Upon annealing in air at 600 °C, the surface of the LSC_650°C undergoes a structural change from a Sr-rich LSC state to a SrO/Sr(OH)[subscript 2]-rich phase-separated state. The partial blockage of the surface with the heterogeneously distributed SrO/Sr(OH)[subscript 2]-rich phases, the decrease in oxygen vacancy content, and the deterioration of the electron transfer properties as evidenced from the Co oxidation state near the surface are found responsible for the severe electrochemical deactivation of the LSC_650°C. These results are important for advancing our ability to tailor the electrochemical performance of solid oxide fuel cell cathodes by understanding the relation of surface chemistry and structure to the oxygen reduction activity and stability, and the dependence of cation segregation on its driving forces including material microstructure.United States. Dept. of Energy. Office of Nuclear EnergyIdaho National Laborator