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Palm oil mill's co-products (empty fruit bunch – EFB and palm oil mill effluent – POME) management is a matter of concern in Indonesia. Co-composting is a promising waste management practice that would allow a reduction of environmental impact and a restitution of organic matter to the soil. This study is a part of a Life Cycle Assessment (LCA) project and aims to pinpoint the most environmentally impacting compartments of the palm oil production chain. It deals more specifically with the Life Cycle Inventory of data on the composting process based on site specific data. Data on the recycled biomass, energy demand and yielded compost properties were recorded in an industrial palm oil mill over one year. Due to the local conditions, high nutrient leaching from the compost were recorded and the compost remained very wet and hot (thermophilic phase). The composting process only led to 40% of methane avoidance compared to anaerobic digestion of POME, and the global nutrient recovery efficiency was below 50%. We identified the following critical parameters to increase environmental benefits from composting: i) the POME/FFB ratio from the mill ii) the roofing of the composting platform, iii) the POME/EFB ratio, iv) the turning frequency, v) the recycling of leachates and vi) the process duration and drying period. The nutrient recovery and the doses of compost applied in the field depend on all of those inter-connected parameters. The data presented will be used within LCA models to assess net environmental benefits from various POME and EFB co-composting systems.

Reforestation experiments and rehabilitation of riparian areas are key in retaining wildlife and improving local ecosystems in plantations-dominated landscapes [1; 2]. In parallel tree crop plantations are increasingly implementing agro-ecological approaches which rely on environmental services [3] thus asking fo planting designs to change and integrate forest species. In the Sabah state of Malaysia, several groups including members of the PONGO (Palm Oil NGOs) Alliance have restored and reforested riparian areas for more than 10 years using native forest species including pioneer ones that quickly grow a canopy and fruit trees that provide food to wildlife. In parallel, agricultural practices in plantations are changing as a response to growing social and environmental concerns. Plantation management increasingly relies on agro-environmental services, which means that basic agricultural functions such as soil preservation, pollination, or pest control can be performed by living organisms (plants, insects, microbes…) [3]. Changes in practices will have to involve new planting designs aimed at mixing selected forest species with plantation crops. A series of measurements will help in characterizing both the performance and the resilience of mixed agroforestry systems compared to traditional planting designs. Changes in wildlife diversity and abundance must be monitored together with the impact of agroforest designs on yields and resistance to both biotic and climatic stress.

The concept and methods to assess soil quality have been widely debated in the literature for the last twenty years. We developed a new framework to assess soil quality following an integrative approach based on the measurement of soil dynamic functions rather than stocks, namely Biofunctool®. Biofunctool® accounts for the interactions between soil physico-chemical properties and soil biological activity. It consists of twelve in-field, time- and cost- effective indicators to assess three main soil functions: carbon transformation, nutrient cycling and structure maintenance. Firstly, the capacity of Biofunctool® to assess the impact of land management on soil quality was validated through a reliability, redundancy and sensitivity analysis. The results over 250 sampling points in Thailand showed the relevance of each of the twelve indicators to assess soil functioning. Secondly, we applied Biofunctool® and aggregated the indicators in a Soil Quality Index that synthetize the impact of land management on soil quality. Biofunctool® was applied within various contexts (tree plantations, agroforestry, conservation agriculture etc.) and two cases study will be presented: i.) impacts of a disturbance gradient based on various land uses and rubber tree stands in Thailand ii.) impacts of conservation agriculture practices in Cambodia. The overall results proved that Biofunctool® index provides a synthetic soil functioning score that is sensitive to land management and is robust in various pedo-climatic contexts. Therefore, Biofunctool® is a reliable tool to assess the soil integrated functioning, i.e., soil quality, and could be included within larger environmental impact assessment frameworks.

The demand for LCA studies on agri-food value chains from South contexts is growing, but the application of LCA in these contexts is challenging. An initiative has been launched to formalize best practices based on the field experience from LCA experts for South contexts. Specificities of the application of LCA in these conditions relate to the diversity and complexity of production conditions and systems, the limited awareness and capacities in LCA as environmental assessment tool by stakeholders, the lack of specific background data, the scarcity and often low-quality of statistic data on studied systems, and the limits imposed to LCA commissioned from abroad. The guidelines in preparation will mainly focus on practical aspects of goal and scope definition, data collection and partnership, inventory and interpretation for key stakeholders.

Soil is a rare natural resource and it is at the center of the main issues in agronomy, environment and land use planning. At global level, erosion is one of the major soil degradation processes and it is responsible for the decrease in agronomic potential of soils and in agricultural land surfaces. Water and soil conservation works (WSCW) are built to protect soil from erosion. The financial and environmental cost the WSCW construction is very high. However, the positive impacts of WSCW are not taken into account in Life Cycle Assessment (LCA). The objectives of this study is to intergrate the impact of WSCW on soil quality in LCA. There are different types of WSCW with different functions and they act differently on erosion process. In this study we focussed on contour ridges (CR) because they are associated to crop systems. CR are generally built in upland areas to reduce runoff and erosion, to increase on-site deposition of eroded particles and to increase local water infiltration. They modify water and soil flows at catchment scale, so it is necessary to use a model able to calculate the inventory flow at the catchment and not at the plot level. In this study we present a methodology to integrate the impact of CR on topsoil erosion at the catchment level and to compute characterization factors in presence of such WSCW. The proposed method was applied in a case study in semi-arid context in central Tunisia (Merguellil watershed) which presents the issues of over-exploitation of water resources, accelerated land degradation and a high expansion of conservation works. In order to investigate the impact of WSCW on topsoil erosion, diffrent catchment scenarios (with and without CR) and land use types were tested using soil redistribution model (LandSoil model). For life cycle impact assessment, we focussed on two midpoint impact categories of LANCA soil functions : erosion resistance and mechanical infiltration. The CFs were calculated using the two models : LANCA and LandSoil models. These CFs were then compared. The results showed how contour ridges can modify topsoil erosion process, the erosion impact depend on location of landuse and contour ridges increase mechanical infiltration of soil. However, these impacts were not considered in LANCA model. In conclusion, It is necessary to integrate the positive impacts of contour ridges in life cycle assessment. It will be also neccessary to integrate the impact of the other types of WSCW in topsoil erosion impact modelling.

Oil palm is largely criticised for its impact on the environment. According to Life Cycle Assessment studies, the agricultural stage proved to be a major contributor to most of the potential environmental impacts, notably global warming, eutrophication and acidification. Focusing on global warming impact, main contributors are land use change and peat cultivation, N-related GHG emissions from fertilisers and residues in the plantation and methane emissions from palm oil mill effluent (POME) treatment. Impact from POME can be drastically reduced if POME is used for composting or if the biogas from anaerobic treatment is captured with electricity recovery. However, the impact from the plantation establishment becomes overwhelming when forests or peatland areas are converted to palm plantations. Oil palm plantations have significantly driven deforestation in Indonesia, together with logging and mining. It remains the most important agricultural driver despite the governmental moratorium and the certification schemes in place since 2011 and 2007; respectively. In order to protect primary forests and peatlands, which is absolutely mandatory to avoid irreversible carbon and biodiversity losses, it is paramount to define a sustainable land planning at national and landscape levels, as well as to implement agroecological practices in the plantations in order to sustainably increase yields and limit further land clearing.

The assessment of soil quality is a scientific issue that has been widely debated in the literature for the last twenty years. We developed the Biofunctool® framework to assess soil quality based on an integrative approach that accounts for the link between the physico- chemical properties and the biological activity of soils. Biofunctool® consists of a set of twelve in-field, time- and cost- effective indicators to assess three main soil functions: carbon transformation, nutrient cycling and structure maintenance. Firstly, a reliability, redundancy and sensitivity analysis was performed to validate the capacity of the set of indicators to assess the impact of land management on soil quality. The results showed the relevance and consistence of each of the twelve indicators to assess the soil functioning. Secondly, we applied Biofunctool® to assess the impact of various land use contexts and agricultural practices on soil quality. In order to consolidate the information gathered by all the indicators, we aggregated it through a Soil Quality Index. The Biofunctool® index was applied in rubber tree plantations along three study sites in Thailand, as well as in forests and intensive cash crops to cover various land use changes and management practices in various pedo-climatic contexts. The results were analyzed site by site to investigate the impact of land use change, management practices and rubber stand ages on soil quality. The results proved that Biofunctool® index can provide an aggregated synthetic soil functioning score that is sensitive to land management and is robust in various pedo-climatic contexts. First, the index revealed the impact of the conversion from annual crop to rubber plantations and order rubber plantation regarding to a natural forest reference. Then, it showed the positive effect of legume cover-crop on the soil functioning. Finally, it highlighted a similar improvement of the soil quality with the age of rubber plantations in contrasted pedo-climatic contexts. Therefore, the Biofunctool® index is a reliable and relevant descriptor of the soil integrated functioning, i.e., soil quality, and could be included in more global approaches of environmental impact assessment.

The proposed 4 per mille initiative aims at assessing soil organic carbon dynamics affected by land management in various and numerous ecosystems. However, assessments based on soil organic carbon dynamics face methodological and experimental shortages. First, SOC assessments may not be sensitive enough to rapid land management changes, due to the long term turnover of SOC (Dignac et al., 2017). Indicators based on soil fractions seems more adapted but this method is strenuous and time consuming and not well adapted for land managers. A new framework was proposed by Hurisso et al., (2016) to assess soil carbon dynamics, linking two indicators of soil carbon fractions (POXC and Basal Soil Respiration). This framework proved to be sensitive to land managements, and may be applied with cost- time-effective indicators in the field. Strictly following this framework, this study presents a first in situ application of the POxC and SituResp® indicators along a perturbation gradient based on rubber tree cultivation in Thailand. The indicators were applied in five study sites to follow a pedo-climatic gradient and finally resulted in 210 sampling points. A predictive model was then developed to avoid the site-specific calibration step and the model was validated among the literature data. The aggregation of the results at the site-scale proved to provide generalizable conclusions on the soil carbon dynamics, from the conversation of an intensive cash cropping system to various rubber tree stand ages, bounded by natural forest reference. Then, the model, integrating soil properties variables, proved to be robust under the pedo-climatic conditions treated, and validated against literature data. This first in situ study and the model developed are promising for the further application of the two indicators in more contrasted contexts. The methods may easily be implemented as a preliminary assessment tool in order to conceptualize new management practices that sustain soil carbon stabilization.

Life Cycle Initiative (LCI) was jointly established by SETAC and UN Environment in 2002. This initiative is a multi-stakeholder partnership enabling the global use of credible life cycle knowledge by private and public decision makers. The overarching goal of the initiative is to provide science-based life cycle knowledge, advices and capacity building in order to enlighten public and business decisions to help to reach the sustainable development goals (SDGs). This initiative has been playing a key role in providing recommendations on life cycle impact characterisation by organising scientific workshops, where scientists and other stakeholders come together to review best available methods and agree on operational recommendations, and by publishing global guidance documents. In June 2018, the second Pellston Workshop® took place in Valencia bringing 43 people together for one week to work and decide on recommendation updates. This present paper recalls the consensus building process and provides key insights on the outputs from this second international workshop.

Palm oil mill's co-products (empty fruit bunch – EFB and palm oil mill effluent – POME) management is a matter of concern in Indonesia. Co-composting would allow dealing with them along with a restitution of organic matter to the soil. This project is a part of a Life Cycle Assessment (LCA) study and aims to pinpoint the most environmentally impacting compartments of the palm oil production chain. This study deals more specifically with the Life Cycle Inventory of data on the composting process based on experimental data. Data on the recycled biomass, energy demand and yielded compost properties were recorded over one year. Due to the experimental conditions, excessive nutrient leaching from the compost were recorded and the compost remained very wet and hot (thermophilic phase) at the end of the first trial due to the spraying of compost with raw and hot POME. We identified the following critical parameters to be accounted for to improve the composting process: i) the roofing of the composting platform, ii) the POME/EFB ratio, iii) the turning frequency, and iv) the process duration to reach given final moisture. The nutrient content and the applied doses of the final compost depend on all these connected parameters. The produced data will be used to develop LCA models for CPO production in order to assess the potential net environmental benefits from POME composting.

Integrating a soil quality indicator within the Life Cycle Assessment (LCA) is necessary to assess the impact of land use on ecosystem services and related area of protections. Despite recent developments in the area, it remains difficult to find a consensus to integrate such an indicator due to the complex definition and assessment of soil quality. We propose a new way to integrate soil quality within LCA based on an integrative conception of soil quality that aims to assess directly the results of soil functions. First, we adapted a land management factor from the IPCC factors to quantitatively define the impact of various management practices on soil quality. Second, using this factor we calibrated a predictive model based on in-field soil quality integrative assessment from the Biofunctool® index. Over five experimental sites in a regional context of South East Asia, we proved that it is possible to predict the impact of land management on soil functional quality, with a restricted set of input parameters. Further studies on larger data set, in other contexts, may strengthen the approach and will make it possible to apply the model at a global scale to meet the LCA application requirements.

Chapitre 12; Explorer les dynamiques territoriales par la modélisation: le cas du palmier à huile en Indonésie

Effets environnementaux des changements d'affectation des sols liés à des réorientations agricoles, forestières, ou d'échelle territoriales : une revue critique de la littérature scientifiques. Synthèse du rapport d'étude