Aggregating sustainability indicators: beyond the weighted sum.

Sustainability analysts and environmental decision makers often overcome the difficulty of interpreting comprehensive environmental profiles by aggregating the results using multi-criteria decision analysis (MCDA) methods. However, the wide variety of methodological approaches to weighting and aggregation introduces subjectivity and often uncertainty. It is important to select an approach that is consistent with the decision maker's information needs, but scant practical guidance is available to environmental managers on how to do this. In this paper, we aim to clarify the theoretical implications of an analyst's choice of MCDA method. By systematically examining the methodological decisions that must be made by the analyst at each stage of the assessment process, we aim to improve analysts' understanding of the relationship between MCDA theory and practice, and enable them to apply methods that are consistent with a decision maker's needs in any given problem context.

Red meat production in australia: life cycle assessment and comparison with overseas studies.

Greenhouse gas emissions from beef production are a significant part of Australia's total contribution to climate change. For the first time an environmental life cycle assessment (LCA) hybridizing detailed on-site process modeling and input-output analysis is used to describe Australian red meat production. In this paper we report the carbon footprint and total energy consumption of three supply chains in three different regions in Australia over two years. The greenhouse gas (GHG) emissions and energy use data are compared to those from international studies on red meat production, and the Australian results are either average or below average. The increasing proportion of lot-fed beef in Australia is favorable, since this production system generates lower total GHG emissions than grass-fed production; the additional effort in producing and transporting feeds is effectively offset by the increased efficiency of meat production in feedlots. In addition to these two common LCA indicators, in this paper we also quantify solid waste generation and a soil erosion indicator on a common basis.

Environmental comparison of biosolids management systems using life cycle assessment.

To fill a gap in the information available to nonmetropolitan policy makers, eight scenarios combining processing technologies and end-uses for biosolids products associated with a 40,000 equivalent-person town were modeled using environmental life cycle assessment (LCA). An uncertainty analysis examined several key assumptions. The results showed that the reuse of biosolids products can be environmentally beneficial but transportation distances can change the preferences between technologies, and drying biosolids using petrochemical methane rather than biogas (produced endogenously in the wastewater facility) significantly worsens environmental performance. System scale can also invert option preferences. This work demonstrates an application of LCA to a strategic engineering question. We also examine the methodological feasibility of considering carbon sequestration and water offsets beyond those typical of previous studies. As the development of scientific data regarding the benefits of biosolids recycling develops,there may be potentialto reward agricultural businesses that choose to reduce their environmental burdens using biosolids. A life cycle management approach to this will be necessary.