The environmental challenges raised by urban food supply requirements must be addressed and sustainable local food policies need to be designed. For these reasons, the major areas of improvement should be identified in terms of both consumption and production. This paper aims at implementing Life Cycle Assessment (LCA) to achieve a comprehensive diagnosis of the environmental impacts of food supply at a city level, and to provide adequate recommendations on how to perform data collection. Initially designed to quantify the environmental performance of a product or service, proposals have been made to adapt LCA to city and territory scales. However, applications are still scarce, as data collection can be very resource-intensive. Most existing studies apply a top-down approach that presents a number of limitations. For example, an overly aggregated representation of the studied sectors is proposed, while mainly greenhouse gas impacts are quantified without addressing a broad coverage of environmental issues. In this paper, a bottom-up approach is adopted, where the collected data concerns a comparison between two data sources involving individual food consumption (i.e. a national and a local survey). AGRIBALYSE 3.0 database is used for life cycle inventories of food products and different methods are employed to scale up the analysis to city level. Results indicate that the main impacts arise from animal product consumption and agricultural production stages, with certain variations according to the impact category and considered food product. A comparison between national and local data on food consumption confirms that average national data are sufficient for an initial diagnosis. One of the next challenges will be to improve the LCA databases. Although they now include several hundred foodstuffs, they do not distinguish between alternative practices (e.g., for agricultural or retailing step) and product sources.

CONTEXT: To design policies for sustainable irrigation planning, public decision-makers need knowledge about the potential environmental impacts of irrigated farming systems. In a previous paper, we proposed to couple Life Cycle Assessment (LCA) and Agrarian System Diagnosis (ASD) to build the Life Cycle Inventory (LCI) of a farming region in a context of data scarcity and farming system diversity. This method was applied to the semi-arid irrigated plain of Kairouan (Tunisia). OBJECTIVES: The aim of the present paper is to demonstrate how this new ASD-based LCA method is used to conduct the impact assessment of this farming region, under current conditions and for two prospective scenarios. METHODS: Two functional units (FU) were used: the area and the gross product generated. Life Cycle Impact Assessment (LCIA) was conducted based on a multilevel process, by converting LCI data collected for each cropping/ livestock system into LCIA outputs, which were then consolidated at the farming system (FS) and at the regional scales. Two model scenarios were built: the agrarian scenario (shift from family to corporate farming) and the hydrological scenario (water table drawdown). RESULTS: Environmental hotspots were identified at each scale: the most impactful FS was the « mixed family farming » (intermediate access to water), because of its large share of land territory (45%). In this FS, the most harmful cropping system was input-intensive olive groves intercropped with a melon-pepper/ cereal/ tomato rotation, in which most impacts (35%) were attributable to the input-intensive “melon” crop, and more particularly to " manufacture and transport of fertilizer", including farmyard manure. Globally, the most harmful processes were water depletion and fertilizer use (fertilizer manufacturing and transportation). This downscaling is very useful to inform public policies on the most harmful productions. The scenarios resulted in impact increases of 11%, 2%, 9% and 23%, 27% and 40%, in human, ecosystem and resource endpoints for the agrarian and hydrological scenarios respectively. SIGNIFICANCE: Our method has three main strengths: i) inter-farms synergies are accounted for in the LCIA, which is essential to promote circularity; ii) the origins of environmental hotspots can be investigated and later mitigated by future policies; iii) ASD helps to design scenarios by identifying current trends and thresholds (resources, pollution and workforce) that cannot be overcome on the territory. Lastly, to build policies for sustainable irrigated agriculture, we encourage the use of this method in participatory approaches.

CONTEXT: To design policies for sustainable irrigation planning, public decision-makers need knowledge about the potential environmental impacts of irrigated farming systems. In a previous paper, we proposed to couple Life Cycle Assessment (LCA) and Agrarian System Diagnosis (ASD) to build the Life Cycle Inventory (LCI) of a farming region in a context of data scarcity and farming system diversity. This method was applied to the semi-arid irrigated plain of Kairouan (Tunisia).OBJECTIVES: The aim of the present paper is to demonstrate how this new ASD-based LCA method is used to conduct the impact assessment of this farming region, under current conditions and for two prospective scenarios.METHODS: Two functional units (FU) were used: the area and the gross product generated. Life Cycle Impact Assessment (LCIA) was conducted based on a multilevel process, by converting LCI data collected for each cropping/ livestock system into LCIA outputs, which were then consolidated at the farming system (FS) and at the regional scales. Two scenarios, based on observed trends, were assessed: the "agrarian" scenario (driven by a shift from family to corporate farming) and the "hydrological" scenario (driven by a water table drawdown).RESULTS: Environmental hotspots were identified at each scale: the most impactful FS was the "mixed family farming" (intermediate access to water), because of its large share of land at the regional scale (45%). In this FS, the most harmful cropping system was input-intensive olive groves intercropped with a melon-pepper/ cereal/ tomato rotation, in which most impacts (35%) were attributable to the input-intensive "melon" crop, and more particularly to "manufacture and transport of fertilizer", including farmyard manure. Globally, the most harmful processes were water and fertilizer use (fertilizer manufacturing and transportation). This downscaling is very useful to inform public policies on the most harmful productions. The impacts in human, ecosystem and resource endpoints increased by 11%, 2%, 9% and 23%, 27% and 40%, for the agrarian and hydrological scenarios respectively.SIGNIFICANCE: These results show that observed trends in farming practices evolution (more irrigation) should be stopped. Our method has three main strengths: i) inter-farms synergies are accounted for in the LCIA, which is essential to promote circularity; ii) thanks to the innovative and multilevel approach, the origins of environmental hotspots can be investigated and later mitigated by future policies; iii) ASD helps to design sustainable scenarios by identifying current trends and regional thresholds (resources, pollution and workforce) that cannot be overcome.

Viticulture needs to satisfy consumers' demands for environmentally sound grape and wine production while envisaging adaptation options to diminish the impacts of projected climate change on future productivity. However, the impact of climate change and the adoption of adaptation levers on the environmental impacts of future viticulture have not been assessed. This study evaluates the environmental performance of grape production in two French vineyards, one located in the Loire Valley and another in Languedoc-Roussillon, under two climate change scenarios. First, the effect of climate-induced yield change on the environmental impacts of future viticulture was assessed based on grape yield and climate data sets. Second, besides the climate-induced yield change, this study accounted for the impacts of extreme weather events on grape yield and the implementation of adaptation levers based on the future probability and potential yield loss due to extreme events. The life cycle assessment (LCA) results associated with climate-induced yield change led to opposite conclusions for the two vineyards of the case study. While the carbon footprint of the vineyard from Languedoc-Roussillon is projected to increase by 29 % by the end of the century under the high emissions scenario (SSP5-8.5), the corresponding footprint is projected to decrease in the vineyard from the Loire Valley by approximately 10 %. However, when including the effect of extreme events and adaptation options, the life cycle environmental impacts of grape production are projected to drastically increase for both vineyards. For instance, under the SSP5-8.5 scenario, the carbon footprint for the vineyard of Languedoc-Roussillon is projected to increase fourfold compared to the current footprint, while it will rise threefold for the vineyard from the Loire Valley. The obtained LCA results emphasized the need to account for the impact of both climate change and extreme events on grape production under future climate change scenarios.

Purpose Current field emission modelling and toxicity characterisation of pesticides suffer from several shortcomings like mismatches between LCI databases and LCIA methods, missing characterisation factors, missing environmental compartments, and environmental impact pathways. The OLCA-Pest project was implemented to address these aspects and to operationalise the assessment of pesticides in LCA. Based on this effort, we propose an approach to integrate pesticide emissions into LCI databases. Methods The PestLCI Consensus Model has been developed in order to estimate emission fractions to different environmental compartments. The initial distribution fractions should be linked to the compartments air, agricultural soil, natural soil, and freshwater. Emissions to off-field surfaces are hereby distributed between agricultural soil, natural soil, and freshwater by using surface cover data. Deposition on the crop surface should be recorded in an emission compartment crop with 13 sub-compartments for crop archetypes for both food and non-food uses. Default emission fractions are provided to calculate the emission fractions for different pesticide application scenarios. Results and discussion A sensitivity analysis shows the effects of the application technique, drift reduction, crop and development stage, field width, and buffer zone on the initial distribution fractions of field-applied pesticides. Recommendations are given for the implementation of a set of default initial distribution fractions into LCI databases, for the organisation of metadata, and for the modelling of pesticide residues in food along the supply chain (processing, storage). Priorities for further research are: improving the modelling of pesticide secondary emissions, further extending emission modeling (e.g. additional application techniques, including cover crops), considering metal-based pesticides in emission models, and systematically assessing human health impacts associated with pesticide residues in food crops. Conclusions The proposed approach allows to preserve the mass balance of the pesticide emitted after application, to make a consistent assessment of ecotoxicity and human toxicity, to define a clear and consistent interface between the LCI and LCIA phases, to estimate initial emission distribution fractions based on existing data, to document metadata transparently and efficiently within crop datasets, and to model the removal of pesticide residues in food during processing.

CONTEXT: Policymakers still lack methods to assess the environmental impacts of agriculture at regional scales. Life Cycle Assessment (LCA) is renowned in assessing the environmental footprint of economic activities; however, it has to be adapted to be of use for this purpose.OBJECTIVE: Our objective is to develop a methodology to carry out relevant LCA of agricultural productions at the regional scale, and to address, in particular, two major challenges which are sources of uncertainties in LCA, i.e., data scarcity and farming system diversity.METHODS: We introduce an innovative method for building Life Cycle Inventories (LCI) of agricultural regions, capable of capturing farming system diversity in the context of data scarcity. It combines LCA with Agrarian System Diagnosis (ASD), which has been adapted to meet the heavy data requirements of the LCI step. This method, which we named "ASD-based LCI", was applied to the semi-arid irrigated plain of Kairouan in Tunisia. After ASD is carried out, a typology of farming systems is built using different data sources: literature review and ASD-based data (e.g., historical and landscape analysis, interviews). This paves the way for a stratified sampling of farms, after which each selected farm is studied in-depth, through field visits and extensive interviews, to collect activity data, i.e., data related to energy and material input and output flows (e.g., manure, seeds, electricity) at the crop / livestock level. The data set quality is improved by filling remaining data gaps using various approaches, e.g., analogy, crop modelling, or expert knowledge. The effect of stratified sampling and data gap filling on uncertainty reduction is evaluated using the pedigree matrix approach and the "uncertainty factor" (UF) which determines the uncertainty interval around the mean of any LCI data. RESULTS AND CONCLUSIONS: Nine farming systems including three "corporate agriculture", five "family agriculture" and one "landless farmer" archetypes and seventy cropping and livestock systems were characterized. The pedigree matrix approach showed that with regards to statistics-based data-the uncertainty interval could be reduced twofold, and by a multiple of four with ASD-based LCI, without or with extrapolation, respectively.SIGNIFICANCE: Not only has the ASD-based LCI method proven powerful when building LCI in agriculture at the regional scale with reduced uncertainty, but it is also suited to the quantification of material flow exchanges within the farm and across farms, which is of valuable service when assessing agroecological productions, which promotes circularity.

Urban water systems (UWS) comprise both the existing freshwater ecosystems and the water infrastructure that humans have built to (i) collect, store, treat, and supply water for potable and non-potable uses; (ii) collect, transport, and treat the generated wastewater; and (iii) discharge treated or untreated water to freshwater ecosystems. Analysing UWS emissions, resources, and energy consumption in an integrated manner using life cycle assessment (LCA) is of paramount importance to make wise decisions at the urban scale reaching optimal design, construction, and operation. In this chapter we provide an overview of LCA studies applied to UWS and describe challenges in this field first as a state of the art and second through 3 case studies which balance construction and operation inventories and include different elements of the UWS. The evaluation of water management scenarios in cities becomes more realistic as more UWS elements are included; making conclusions about scenarios of one particular element without considering the entire UWS might lead to misleading conclusions as the elements impact each other in a cascading effect. LCA is well established for wastewater treatment and guidance is now available for practitioners. Similar guidance is needed for other UWS elements (drinking water production, wastewater reuse, etc.) and for their integration.

Initially designed to assess the environmental performance of a product or a service, the methodological framework of LCA has been adapted to be applied to territories. Territories cover a wide range of sub-national systems such as cities, metropolitan areas, agricultural areas, or regions. Territorial LCA approaches have two main goals: (i) providing an environmental diagnosis and (ii) comparing the performances of land planning scenarios. This chapter describes the main principles of territorial LCA approaches according to the four LCA phases, and by differentiating two approaches: (i) type A that focuses on a territorial anchored activity and (ii) type B that adopts a cross-sectoral approach. One of the main adaptations relies on the handling of multifunctionality and the computation of an eco-efficiency ratio. Then, an extensive overview of territorial LCA applications is provided. Finally, combinations with other tools such as metabolism studies, geographic information system (GIS), or economic modelling are discussed.

This paper aims to assess the conditions under which hydraulic projects can be considered as an efficient option, from an environmental point of view, to secure water supply of agricultural areas using the Territorial Life Cycle Assessment (T-LCA) methodology. Firstly, the environmental performance of three theoretical agricultural landuse planning scenarios are defined: (1) a business-as-usual case without irrigation, (2) irrigation with an InterBasin Water Transfer (IBWT) and (3) with an Agricultural Reservoir (AR). These are all assessed by computing the territorial eco-efficiency (i.e. a ratio between the services provided by land planning scenarios and their related environmental impacts). Secondly, Territorial Life Cycle Assessment methodology was used to assess the water-energy-infrastructure nexus between the two hydraulic projects. Results indicate that the ecoefficiencies of the scenarios vary according to the service considered and to the type of land use. For land management or economic functions, the scenario without irrigation can perform better, while hydraulic projects are more eco-efficient for functions related to biomass production. The analysis of the water-energyinfrastructure nexus highlights the trade-offs between the two types of project. On one hand, IBWT allows for the use of a low-stress water resource and less energy, but may require high material consumption. On the other hand, AR uses less material while relying on a more scarce water resource. IBWT performs better than AR if the pipe length is less than 100 km, with a water allocation of 1% (proportion of the infrastructure allocated to the considered agriculture area). This study underlines the importance of considering the territorial context in the environmental assessment of land planning projects in order to support decision-making.

Aujourd’hui, il existe une norme internationale (ISO 14046) qui definit ce qu’est une empreinte eau mais qui reste encore tres difficile d'acces aux non-specialistes. La Chaire ELSA-PACT, associee aux partenaires du projet ANR MINIMEAU, a concu et realise un memento graphique, qui vise a rendre accessible cette norme de maniere pedagogique, operationnelle et synthetique. L'ouvrage illustre les notions theoriques principales, les outils de mise en œuvre operationnelle et donne des exemples

Global value chains and climate change have a significant impact on water resources and increasingly threaten freshwater ecosystems. Recent methodological proposals for life cycle impact assessment (LCIA), evaluate water use impacts on freshwater habitats based on river hydraulic parameters alterations. However, they are limited to French rivers due to lack of global data and models. On this basis, this article proposes an approach to compute regionalized characterization factors for modeling river habitat change potential (HCP) induced by water consumption, potentially applicable worldwide. A simplified model is developed for fish guilds and invertebrates. Based on French datasets, it establishes a relationship between HCP and river hydraulic parameters. A methodology to derive discharge and hydraulic geometry at the reach scale is proposed and applied to European and Middle Eastern rivers below 60°N latitude. Regionalized HCPs are calculated at the river reach scale and aggregated at watershed. Then, the impact of agricultural water use in contrasted European and Middle Eastern countries is evaluated comparing the outcomes from the HCP and the Available Water Remaining (AWARE) models at the national scale, considering water supply mix data. The same analysis is carried out on selected river basins. Finally, result consistency, uncertainty and global applicability of the overall approach are discussed. The study demonstrates the reproducibility of the impact model developed for French rivers on any hydrographic network where comparable ecological, hydrological and hydraulic conditions are met. Furthermore, it highlights the need to characterize impacts at a higher spatial resolution in areas where HCP is higher. Large scale quantification of HCP opens the way to the operationalization of mechanistic LCIA models in which the habitat preferences of freshwater species are taken into account to assess the impacts of water consumption on biodiversity.

Wastewater reuse (WW-reuse) is an alternative water resource that may answer present and future water-scarcity issues, supplying diverse categories of water users: agricultural, industrial or even domestic. A literature review of 30 LCAs of WW-reuse case studies highlights that the majority are located in arid or semi-arid climates, with a third in coastal areas, thus illustrating the historical development of WW-reuse. However, the conclusions for these very site-specific cases (local conditions) cannot be extrapolated to all other situations where WW-reuse issues arise (continental location, temperate climate, etc.). The review also reveals that the assumptions and calculation approaches used in these case studies were not homogeneous. The aim of this study is therefore to propose a homogeneous conceptual framework for the evaluation of the environmental efficiency of WW-reuse, based on an adapted system boundary, a transparent and solid water balance as well as a comparison with a standardized reference system for water supply, applicable to all local situations. Through the application of this framework to urban WW-reuse for agricultural irrigation, various parameters are analysed to identify parameters that drive the WW-reuse eco-efficiency relative to archetypes of water supply mix (WSmix). Two wastewater regeneration treatment alternatives with contrasting energy demands are assessed in order to evaluate the range of reclaimed water quality that might be requested by local water policies. Four main parameters are adjusted to compare the scenarios across a panel of contrasting situations: the geographical situation (coastal or continental), the level of water scarcity, the origin of the local water resource and the composition of the electricity mix. Overall results highlight situations where reclaimed water is clearly recommended from an environmental point of view (as for coastal water-scarce situations or when compared to desalinated water) and others where it is less eco-efficient than the local WSmix (energy-intensive regeneration treatment in a continental area for instance). The nutrient content of treated urban wastewater, following denitrification during wastewater treatments, is not sufficient to provide significant environmental benefits (avoided fertilizer production) to the WW-reuse scenarios. A paradigm shift in the design of wastewater treatment plants could be a source of eco-efficiency for WW reuse, allowing for optimal recovery of the nutritional content from the wastewater.

Life Cycle Inventory (LCI) data are the backbone of Life Cycle Analysis (LCA).They reflect modelling choices made by the LCA practitioner that can strongly influence the results of environmental impact calculations.The high sensitivity of these data are the reason why they must be accurately documented and tend to the highest possible quality.High quality, well documented LCI data can also be shared between LCA practitioners, allowing productivity gains and better research reproducibility, in particular between practitioners who do not work on the same life cycle inventory database.Unfortunately, SimaPro (PRé Sustainability B.V., 2020), one of the most used LCA software solutions, has only limited features to document, review and exchange LCI data.ELDAM has been developed to fill this gap.

Decentralised wastewater management (DWM) systems are deployed in areas where the topography does not allow for gravity flow to a centralised system, or requires a complex and expensive pumping station network. Also, DWM systems are often the only option in rural areas where there are no sewage transport networks. This paper aims at addressing the question of the degree to which DWM systems can be considered as viable alternatives from an environmental point of view using the Life Cycle Assessment (LCA) methodology. First, the environmental sustainability is investigated to identify environmental hotspots in two (nature-based and engineered) onsite DWM systems. Second, DWM scenarios are compared against centralised wastewater management (CWM) scenarios using a whole-systems approach. Finally the boundary conditions under which a given DWM scenario performs better than a CWM scenario are discussed. Results show CWM scenarios were less sustainable than DWM scenarios on the resources endpoint due to their sewer infrastructures, however CWM scenarios performed better than DWM scenarios on the ecosystems quality endpoint due to their well-managed air emissions and discharges. While on human health no clear conclusion could be drawn. Finally, for relatively few households (subject of the study in rural areas) CWM scenarios did not score superior performances compared to DWM scenarios on all three endpoint indicators. Yet for a greater number of households it was impossible to decide in favour of decentralisation because of a lack of favourable consensus on all three endpoint indicators.

This study shows how a research collective modified the mixed crop-livestock system used by INRAE's experimental farm in Saint Laurent de la Free (between 2009 and 2017) and thus increased feed self-sufficiency for the farm's livestock herd. Notably, links between crop and livestock production were strengthened. We used data on the farm's structure and function to illustrate a potential pathway to feed self-sufficiency. We examined the changes made to the production system and explored the reasons behind the choices made. Key indicators show that feed self-sufficiency was attained after six years. Using a system for scoring coupling strength, we found that the degree of coupling between crop and livestock production went from intermediate (2009-2012) to high (2013-2017). We identified the key challenges associated with transitioning to feed self-sufficiency and explored how the farm's new circumstances translated into technical and economic performance. Finally, the farm recently converted to organic production, opening the door to new possibilities for maintaining or even improving feed self-sufficiency, as well as other forms of self-sufficiency (e.g., straw, nitrogen, energy).