Contributions to LCA methodology for agricultural systems : Site-dependency and soil degradation impact assessment /

Consultable des del TDXTítol obtingut de la portada digitalitzadaEl Análisis de Ciclo de Vida (ACV o LCA, en sus siglas inglesas) es un método para el análisis ambiental de sistemas industriales. Esta tesis estudia la aplicabilidad del ACV a sistemas agrícolas, y propone soluciones para algunas de las lagunas detectadas en el método. A partir de un estudio de la producción de manzanas en Nueva Zelanda, se analiza cuáles son los factores que determinan mayormente los resultados del ACV agrícola. Se ha demostrado que el tipo de tecnología agrícola (p. ej.: agricultura integrada o ecológica) decide algunos tipos de impacto ambiental (toxicidad humana, consumo de energía…), aunque no es suficiente para predecirlos. De hecho, los resultados de la tesis demuestran la especial relevancia de disponer de datos sobre las características del sitio en qué se desarrolla la producción, dada la especial relevancia que estas características desempeñan en la determinación de los impactos ambientales de la agricultura. En especial, las condiciones físicas del sitio de producción (tipo de suelo, clima) y la técnica del productor (es decir: cómo aplica el productor la tecnología, a través del grado de mecanización, cantidad de fitosanitarios y fertilizantes utilizada, sistema de irrigación…) son los elementos más importantes de estos factores locales. Así, el consumo de energía para las operaciones en el campo presenta variaciones de hasta un 50% en manzanales de un mismo tipo de tecnología (producción ecológica o integrada), debido a las distintas prácticas de los granjeros. En el caso de las condiciones físicas del sitio, las diferencias en el tipo de suelo producen variaciones de hasta un orden de magnitud en las emisiones de pesticidas al agua subterránea, para una misma cantidad y tipo de sustancia utilizada. Los impactos debidos a los pesticidas también están determinados en buena parte por las prácticas de cada granjero, puesto que la elección de las sustancias activas produce grandes variaciones en el efecto sobre la toxicidad de cada uno de los manzanales estudiados. Finalmente, la aplicación del ACV a la producción de manzanas en Nueva Zelanda ha permitido sugerir diversas opciones de mejora, y prever de un modo cuantitativo el efecto de estas mejoras en caso de que se apliquen. Por otra parte, la tesis propone un método para el análisis de los impactos sobre la calidad del suelo en ACV agrícola, utilizando la Materia Orgánica del Suelo (MOS) como indicador. El método sugiere el uso de modelos matemáticos para la predicción de los niveles de MOS afectados por el sistema agrícola, y se ilustra su aplicación por medio de un ejemplo. Este nuevo método de evaluación se evalúa como suficientemente representativo y aplicable para introducir los impactos sobre las funciones de sostén de la vida realizadas por el suelo en ACV, y es especialmente recomendable para incluir estos aspectos en ACV agrícola. En efecto, la aplicación de este método permitirá aumentar la relevancia y la credibilidad de las comparaciones entre sistemas agrícolas que tratan la calidad del suelo de modo distinto, como la agricultura ecológica y la convencional y / o integrada. Además, la aplicación del indicador MOS por medio del uso de modelos matemáticos permitirá aumentar la sensibilidad del cálculo de otras categorías de impacto, como el efecto invernadero (gracias al cálculo de la fijación / emisión de carbono por parte del suelo) y la eutrofización y la lluvia ácida (gracias a la modelización del ciclo del nitrógeno).Life Cycle Analysis (LCA) is a meted for the environmental assessment of industrial systems. This thesis studies the applicability of LCA to agricultural systems, and suggests solutions for some of the weaknesses detected in the method. Based on a study of apple production in New Zealand, the factors mainly determining the results of agricultural LCA are analysed. It has been shown that the type of agricultural technology (e.g.: organic or integrated fruit production) decides some types of environmental impact (human toxicity, energy consumption…), however it is not enough to predict them. Indeed, the results of the thesis show the high relevancy of the characteristics of the site of production on the results of the environmental analysis of agriculture, and therefore to importance of obtaining data on these characteristics for a credible study. Especially, the physical conditions of the site (soil type and weather), and producer's technique (i.e.: how the producer applies the technology type, through the degree of mechanisation, amount of fertilisers used, composition of pesticides, irrigation technique…) are the main elements of these site characteristics. For instance, energy consumption for field operations show differences of up to 50% between apple orchards of the same technology (organic or integrated), due to variations in farmer's practices. In the case of the physical site conditions, the differences in soil types generate variations of up to one order of magnitude in the emissions of pesticides to groundwater, for the same substance applied in the same amount. Impacts from pesticides are shaped by to farmer's practices as well, and the selection of different active ingredients produces great variations in the effect on human toxicity in the different apple orchards. Finally, the application of LCA to apple production in New Zealand has suggested several options for environmental improvement, and has allowed a quantified prediction of the environmental improvement derived from their application. Besides, the thesis suggests a new method for the analysis of impacts on soil quality in agricultural LCA, using Soil Organic Matter (SOM) as an indicator. The method suggests the use of existing mathematic models for the prediction of SOM level evolution as affected by agricultural practices, and its application is illustrated with an example. This new method is representative and applicable enough to include the life support functions of land in LCA, and is especially recommended for the inclusion of the impacts on soil quality in agricultural LCA. Indeed, the application of this method allows for more relevancy and credibility in comparative LCA of agricultural systems that treat soil quality in a different way, such as organic and Conventional / integrated agriculture. In addition, the application of the SOM indicator through the use of mathematic models increases the sensitivity of the calculation of other impact categories such as global warming (thanks to the prediction of carbon emissions / sequestration by soil) and eutrophication and acidification (thanks to the modelling of the nitrogen cycle)

Key Elements in a Framework for Land Use Impact Assessment Within LCA (11 pp)

Background, Aim and Scope: Land use by agriculture, forestry, mining, house-building or industry leads to substantial impacts, particularly on biodiversity and on soil quality as a supplier of life support functions. Unfortunately there is no widely accepted assessment method so far for land use impacts. This paper presents an attempt, within the UNEP-SETAC Life Cycle Initiative, to provide a framework for the Life Cycle Impact Assessment (LCIA) of land use. Materials and Methods: This framework builds from previous documents, particularly the SETAC book on LCIA (Lindeijer et al. 2002), developing essential issues such as the reference for occupation impacts; the impact pathways to be included in the analysis; the units of measure in the impact mechanism (land use interventions to impacts); the ways to deal with impacts in the future; and bio-geographical differentiation. Results: The paper describes the selected impact pathways, linking the land use elementary flows (occupation; transformation) and parameters (intensity) registered in the inventory (LCI) to the midpoint impact indicators and to the relevant damage categories (natural environment and natural resources). An impact occurs when the land properties are modified (transformation) and also when the current man-made properties are maintained (occupation). Discussion: The size of impact is the difference between the effect on land quality from the studied case of land use and a suitable reference land use on the same area (dynamic reference situation). The impact depends not only on the type of land use (including coverage and intensity) but is also heavily influenced by the bio-geographical conditions of the area. The time lag between the land use intervention and the impact may be large; thus land use impacts should be calculated over a reasonable time period after the actual land use finishes, at least until a new steady state in land quality is reached. Conclusions: Guidance is provided on the definition of the dynamic reference situation and on methods and time frame to assess the impacts occurring after the actual land use. Including the occupation impacts acknowledges that humans are not the sole users of land. Recommendations and Perspectives: The main damages affected by land use that should be considered by any method to assess land use impacts in LCIA are: biodiversity (existence value); biotic production potential (including soil fertility and use value of biodiversity); ecological soil quality (including life support functions of soil other than biotic production potential). Bio-geographical differentiation is required for land use impacts, because the same intervention may have different consequences depending on the sensitivity and inherent land quality of the environment where it occurs. For the moment, an indication of how such task could be done and likely bio-geographical parameters to be considered are suggested. The recommendation of indicators for the suggested impact categories is a matter of future researc

Pilot application of PalmGHG, the RSPO greenhouse gas calculator for oil palm products

International audienceThe Roundtable on Sustainable Palm Oil (RSPO) is a non-profit association promoting sustainable palm oil through a voluntary certification scheme. Two successive science-based working groups on greenhouse gas (GHG) were active in RSPO from 2009 to 2011, with the aim of identifying ways of achieving meaningful and verifiable reductions of GHG emissions. One of the outputs of the second group is PalmGHG, a GHG calculator using the life cycle assessment ap-proach to quantify major sources of emissions and sequestration for individual palm oil mills and their supply base. A pilot study was carried out in 2011 with nine RSPO member companies that gave an average of 1.67 t CO2e/t crude palm oil (CPO), with a range of -0.02 to +8.32t CO2e/t CPO. Previous land use and the area of peat soil used were the main causes of the variation. Further modifications to PalmGHG continue to be made in order to make the tool more flexible and comprehensive, to refine default values, and to render it more user-friendly

UNEP-SETAC guideline on global land use impact assessment on biodiversity and ecosystem services in LCA

Purpose As a consequence of the multi-functionality of land, the impact assessment of land use in Life Cycle Impact Assessment requires the modelling of several impact pathways covering biodiversity and ecosystem services. To provide consistency amongst these separate impact pathways, general principles for their modelling are provided in this paper. These are refinements to the principles that have already been proposed in publications by the UNEP-SETAC Life Cycle Initiative. In particular, this paper addresses the calculation of land use interventions and land use impacts, the issue of impact reversibility, the spatial and temporal distribution of such impacts and the assessment of absolute or relative ecosystem quality changes. Based on this, we propose a guideline to build methods for land use impact assessment in Life Cycle Assessment (LCA). Results Recommendations are given for the development of new characterization models and for which a series of key elements should explicitly be stated, such as the modelled land use impact pathways, the land use/cover typology covered, the level of biogeographical differentiation used for the characterization factors, the reference land use situation used and if relative or absolute quality changes are used to calculate land use impacts. Moreover, for an application of the characterisation factors (CFs) in an LCA study, data collection should be transparent with respect to the data input required from the land use inventory and the regeneration times. Indications on how generic CFs can be used for the background system as well as how spatial-based CFs can be calculated for the foreground system in a specific LCA study and how land use change is to be allocated should be detailed. Finally, it becomes necessary to justify the modelling period for which land use impacts of land transformation and occupation are calculated and how uncertainty is accounted for. Discussion The presented guideline is based on a number of assumptions: Discrete land use types are sufficient for an assessment of land use impacts; ecosystem quality remains constant over time of occupation; time and area of occupation are substitutable; transformation time is Negligible; regeneration is linear and independent from land use history and landscape configuration; biodiversity and multiple ecosystem services are independent; the ecological impact is linearly increasing with the intervention; and there is no interaction between land use and other drivers such as climate change. These assumptions might influence the results of land use Life Cycle Impact Assessment and need to be critically reflected. Conclusions and recommendations In this and the other papers of the special issue, we presented the principles and recommendations for the calculation of land use impacts on biodiversity and ecosystem services on a global scale. In the framework of LCA, they are mainly used for the Assessment of land use impacts in the background system. The main areas for further development are the link to regional ecological models running in the foreground system, relative weighting of the ecosystem services midpoints and indirect land use.Fil: Koellner, Thomas . University of Bayreuth. Faculty of Biology, Chemistry and Geosciences; AlemaniaFil: De Baan, Laura. Institute for Environmental Decisions. Natural and Social Science Interface; SuizaFil: Beck, Tabea. University of Stuttgar. Department Life Cycle Engineering; AlemaniaFil: Brandão, Miguel. Joint Research Centre. Institute for Environment and Sustainability, Sustainability. Assessment Unit, European Commission; ItaliaFil: Civit, Bárbara María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Ciencias Humanas, Sociales y Ambientales; Argentina. Universidad Tecnológica Nacional. Facultad Regional Mendoza; ArgentinaFil: Margni, Manuele . École Polytechnique de Montréal. Département de génie chimique; CanadáFil: Milà i Canals, Llorenç. Unilever R&D. Safety and Environmental Assurance Centre; Reino UnidoFil: Saad, Rosie. École Polytechnique de Montréal. Département de génie chimique; CanadáFil: De Souza, Danielle Maia. Joint Research Centre. Institute for Environment and Sustainability, Sustainability. Assessment Unit, European Commission; ItaliaFil: Müller Wenk, Ruedi . University of St. Gallen. Institute for Economy and the Environment; Alemani

Review of methods addressing freshwater use in life cycle inventory and impact assessment

Purpose: In recent years, several methods have been developed which propose different freshwater use inventory schemes and impact assessment characterization models considering various cause-effect chain relationships. This work reviewed a multitude of methods and indicators for freshwater use potentially applicable in life cycle assessment (LCA). This review is used as a basis to identify the key elements to build a scientific consensus for operational characterization methods for LCA. Methods: This evaluation builds on the criteria and procedure developed within the International Reference Life Cycle Data System Handbook and has been adapted for the purpose of this project. It therefore includes (1) description of relevant cause-effect chains, (2) definition of criteria to evaluate the existing methods, (3) development of sub-criteria specific to freshwater use, and (4) description and review of existing methods addressing freshwater in LCA. Results and discussion: No single method is available which comprehensively describes all potential impacts derived from freshwater use. However, this review highlights several key findings to design a characterization method encompassing all the impact pathways of the assessment of freshwater use and consumption in life cycle assessment framework as the following: (1) in most of databases and methods, consistent freshwater balances are not reported either because output is not considered or because polluted freshwater is recalculated based on a critical dilution approach; (2) at the midpoint level, most methods are related to water scarcity index and correspond to the methodological choice of an indicator simplified in terms of the number of parameters (scarcity) and freshwater uses (freshwater consumption or freshwater withdrawal) considered. More comprehensive scarcity indices distinguish different freshwater types and functionalities. (3) At the endpoint level, several methods already exist which report results in units compatible with traditional human health and ecosystem quality damage and cover various cause-effect chains, e.g., the decrease of terrestrial biodiversity due to freshwater consumption. (4) Midpoint and endpoint indicators have various levels of spatial differentiation, i.e., generic factors with no differentiation at all, or country, watershed, and grid cell differentiation. Conclusions: Existing databases should be (1) completed with input and output freshwater flow differentiated according to water types based on its origin (surface water, groundwater, and precipitation water stored as soil moisture), (2) regionalized, and (3) if possible, characterized with a set of quality parameters. The assessment of impacts related to freshwater use is possible by assembling methods in a comprehensive methodology to characterize each use adequatel

Making sense of the minefield of footprint indicators

In recent years, footprint indicators have emerged as a popular mode of reporting environmental performance. The prospect is that these simplified metrics will guide investors, businesses, public sector policymakers and even consumers of everyday goods and services in making decisions which lead to better environmental outcomes. However, without a common “DNA”, the ever expanding lexicon of footprints lacks coherence and may even report contradictory results for the same subject matter.(1) The danger is that this will ultimately lead to policy confusion and general mistrust of all environmental disclosures. Footprints are especially interesting metrics because they seek to express the environmental performance of products and organizations from a life cycle perspective. The life cycle perspective is important to avoid misleading claims based only on a selected life cycle stage. For example, the water used to manufacture beverages may be important, but if a beverage includes sugar, irrigation water used to cultivate sugar cane could be a greater concern. The focus on environmental performance distinguishes footprints from technical efficiency measures, such as energy use efficiency or water use efficiency, which typically only make sense when applied to a single life cycle stage as they lack local environmental context. However, unlike technical efficiency, which can usually be accurately measured and verified, footprint indicators, with their wider view of environmental performance, are usually calculated using models which can differ in scope, complexity and model parameter settings. Despite the noble intention of using footprints to evaluate and report environmental performance, the potential inconsistency between different approaches acts as a deterrent to use in many public policymaking and business contexts and can lead to confusing and contradictory messages in the marketplace

The Challenges of Applying Planetary Boundaries as a Basis for Strategic Decision-Making in Companies with Global Supply Chains

Abstract: The Planetary Boundaries (PB) framework represents a significant advance in specifying the ecological constraints on human development. However, to enable decision-makers in business and public policy to respect these constraints in strategic planning, the PB framework needs to be developed to generate practical tools. With this objective in mind, we analyse the recent literature and highlight three major scientific and technical challenges in operationalizing the PB approach in decision-making: first, identification of thresholds or boundaries with associated metrics for different geographical scales; second, the need to frame approaches to allocate fair shares in the 'safe operating space' bounded by the PBs across the value chain and; third, the need for international bodies to co-ordinate the implementation of the measures needed to respect the Planetary Boundaries. For the first two of these challenges, we consider how they might be addressed for four PBs: climate change, freshwater use, biosphere integrity and chemical pollution and other novel entities. Four key opportunities are identified: (1) development of a common system of metrics that can be applied consistently at and across different scales; (2) setting 'distance from boundary' measures that can be applied at different scales; (3) development of global, preferably open-source, databases and models; and (4) advancing understanding of the interactions between the different PBs. Addressing the scientific and technical challenges in operationalizing the planetary boundaries needs be complemented with progress in addressing the equity and ethical issues in allocating the safe operating space between companies and sectors