Didier Stilmant

Walloon Agricultural Research Centre CRA-W · Department Sustainability Systems and Prospectives

The increasing human population and demand for animal food products raise the issue of impacts of animal systems on food security caused by their use of human-edible feed and/or tillable land. The utility of replacing animal systems with potential food-crop systems needs to be assessed but is associated with many uncertainties. Some metrics analyse...

Increasing the level of feed autonomy is usually considered as a prerequisite for conversion of cattle farms to organic management. This study is aimed at generating references for organic dairy and beef production through a technical and economic assessment of feed autonomy in commercial farms. Data were collected in 2014 and 2015 on 11 farms loca...

List> • Crop diversification is a dynamic pathway towards sustainable agrifood systems. • Technological and institutional barriers restrict uptake of crop diversification. • More coordination and cooperation among agrifood system stakeholders is required. • The European Crop Diversification Cluster calls for multiactor networks. European cropp...

The general purpose of the primary and secondary data available in this article is to support an integrated assessment of scenarios of crop-livestock integration at the territorial level i.e. of exchanges between arable and livestock farms. The data is a result of a research collaboration between the scientist from INRAE, agricultural advisers from...

Crop diversification represents a key lever to support the development of sustainable agri-food systems. Knowledge on trade-offs and carry over effects from different crop diversification strategies is essential to inform agricultural stakeholders of potential costs and benefits. This knowledge is limited by existing data and performance measures p...

The temporal and spatial diversification of crops through rotation, multiple cropping and/or intercropping contribute to low-input agronomic practices and resource-efficient farming systems, and constitute a key pillar of the transition towards sustainable agri-food systems. Crop diversification can fulfil the need to simultaneously produce food, f...

Increasing the level of feed autonomy (self-sufficiency) is usually considered as a prerequisite for conversion of cattle farms to organic farming. Technically it requires adjusting fodder production and feed purchases in terms of quantity and quality to the requirements of the herd. A joint technical and economic assessment of feed autonomy in org...

The dairy sector is challenged to increase its eco-efficiency, which means, minimizing environmental impacts, while maintaining economic viability. To quantify eco-efficiency, multiple environmental and economic indicators are needed. Data envelopment analysis (DEA) has been used to evaluate the eco-efficiency of agricultural systems accounting for...

Purpose Life cycle assessment (LCA) is a useful tool for investigating the environmental performance of agricultural products. For many crop-based products, the agricultural production step shows substantial impacts in LCA results. Using the illustrative case of cereal production in Wallonia, Belgium, the study uses sensitivity analyses to explore...

We build an ABM for simulation of incentives for maize to produce bio-fuels in Luxembourg with an aim to conduct life cycle assessment of the additional maize and the consequent displacement of other crops in Luxembourg. This paper focuses on the discovery of market price for crops. On the supply side we have farmers who are willing to sell their p...

Agent-Based Models (ABMs) are becoming a widespread approach to model human-environment interactions. They belong to the class of individual-based modelling approaches, which allow a bottom-up representation of the system being modelled, eliciting its macro-level evolution while modelling the micro-level behavior of its individuals. This paper deal...

The emission of greenhouses gases (GHG) from ruminant production systems needs to be reduced. This can be achieved partly by better manure management, particularly for deep litter (DL) systems. Two contrasting removal frequency rates (1Â, every 63.5 AE 3.5 days; and 3Â, every 23.1 AE1.5 days) were compared in a DL system for Belgian blue double-mus...

Producing biogas via anaerobic digestion is a promising technology for meeting European and regional goals on energy production from renewable sources. It offers interesting opportunities for the agricultural sector, allowing waste and by-products to be converted into bioenergy and bio-based materials. A consequential life cycle assessment (cLCA) w...

Greenhouse gas emission intensity (GHGI; kilograms carbon dioxide equivalents/kilograms liveweight gain) have to be reduced so as to limit the impact of human activities on global warming while furnishing food to human. In this respect, performances of 654 Belgian Blue double-muscled bulls (BBdm) during their fattening phase were recorded. On this...

Within the framework of the Optenerges project, funded under the Interreg IV program, the greenhouse gas (GHG) emissions of 62 cattle farms representative of the main production systems in the Province of Luxembourg in Wallonia, Belgium were assessed. The main goal of this study was to give reference values for GHG emission intensity in meat produc...

The environmental impact of wheat production was assessed through Life Cycle Assessment (LCA). Local data were collected to characterize Walloon conventional and organic wheat production systems. Two functional units (FU) were investigated: 1kg of wheat grains at 15% humidity and 1ha used for wheat cropping. An uncertainty analysis assessed the sig...

The study examined the prediction error of near infrared reflectance spectroscopy of faeces (FNIRS) in estimations of in vivo organic matter digestibility (OMD) and dry and organic matter voluntary intake (DMVI and OMVI) of forages by ruminants in established calibration datasets from our laboratories. It also examined the repeatability of the FNIR...

Introduction. Consumers are attaching increasing importance to the sustainability of the products they purchase. The agribusiness sector is well aware of this trend and is making efforts to guarantee product sustainability. Literature. Social Life Cycle Assessment (S-LCA) is a widely used methodology (like others in this field, such as ISO 26000 an...

Increasing input self-sufficiency is often viewed as a target to improve sustainability of dairy farms. However, few studies have specifically analysed input self-sufficiency, by including several technical inputs and without only focussing on animal feeding, in order to explore its impact on farm sustainability. To address this gap, our work has t...

Cattle milk production is strongly criticized for its impacts on the environment. For the first time an LCA approach was used to estimate them in southern Belgium. Based on a 9-farms survey, mean (SD) environmental impacts of 1 kg of fat-and-protein-corrected milk were estimated as 8.4 (4.5) g PO4eq, 15.5 (2.8) g SO2eq, 1.4 (0.2) kg CO2eq, 3.0 (2.9...

The biomethane yield of various energy crops, selected among potential alternatives to maize in the Greater Region, was assessed. The biomass yield, the volatile solids (VS) content and the biochemical methane potential (BMP) were measured to calculate the biomethane yield per hectare of all plant species. For all species, the dry matter biomass yi...

Farmers’ practices are characterized not only by complexity at the farm scale, but also by diversity at the regional scale. In order to assess this diversity, a systemic approach is needed for comparing and classifying systems of practice. We developed a cognitive mapping approach (CMASOP) for comparing and clustering these systems within the socia...

Based on the current uses of cereals grown in Wallonia (Belgium), various scenarios defining possible futures for the Walloon cereal sector have been created. Purpose. These scenarios lay the basis for research aiming at assessing the sustainability of food and non-food uses of cereals. Method. Based on contrasted hypotheses, four scenarios for the...

More than 60% of the arable cropped area in Wallonia is dedicated to cereals. Cereal chains were initially aimed at ensuring food security but are now progressively oriented towards new non-food uses. Walloon cereal chains are now having to face up to new global challenges: to ensure the competitiveness and sustainability of vegetal and animal chai...

Background: An optimal valorization of plant biomasses to produce biofuels requires a good knowledge of the available contents and molecular composition of the main chemical components, which changes with the harvesting date. Therefore, we assessed the influence of harvesting date on the chemical characteristics of various energy crops in the cont...

Social--Ecological Systems (SES) are complex due to uncertainty related to their nature and their functions. In these systems, decision-making processes and practices of managers are often value-laden and subjective, dominated by their world-views and their own knowledge. People's knowledge are central in building their adaptive capacity but are se...

The chemical composition of 1052 samples covering 49 plant species is summarized in this paper. The analyzed biomasses offer a wide range of chemical compositions, monosaccharidic compositions of hemicelluloses, enzymatically digestible organic matter, and bioethanol potential. Nevertheless, their thermal energy value remains in a narrow range on a...

This paper presents a new cognitive mapping approach for analysing systems of practices in social–ecological systems. These systems are mapped from people's views collected during open-ended interviews. Cognitive maps are made up of diverse variables (e.g., operations, drivers, constraints) linked to each other by a range of relationships: cause–ef...

Evaluation of the third Action Programme. Recommendations for regulatory and scientific research. In accordance with the Nitrates Directive, the third "Durable Nitrogen Management Plan" (PGDA) will be soon reviewed in Wallonia (Belgium). The second "Nitrate – Water" workshop took place between 28th May and 1st June 2012. The workshop was attended b...

In accordance with the Nitrates Directive, the third "Durable Nitrogen Management Plan" (PGDA) will be soon reviewed in Wallonia (Belgium). The second "Nitrate - Water" workshop took place between 28th May and 1st June 2012. The workshop was attended by both Belgian scientists (Université catholique de Louvain - UCL, Walloon Agricultural Research C...

Grassland, which accounts for half of the agricultural area in Wallonia, forms the basis of many ecosystemic services: cultural, grass production, regulatory services, etc. Nevertheless, the poor ability of cattle to fix ingested nitrogen leads to significant N rejection during grazing. N is excreted in concentrated form via urine, and thus becomes...

The effects of first calving (FC) in Holstein heifers on their first lactation, second lactation and lifetime milk production were examined from an initial database of 459 743 animals that first calved between 1 January 1990 and 31 July 2010 in Wallonia, Belgium. The FC age class (18 to 22, 22 to 26, 26 to 30, 30 to 34, 34 to 38 and 38 to 42 months...

Intensive livestock farming has raised issues about environmental impacts and food security during the past 20 years. As a consequence, there is a strong social demand for sustainable livestock systems. Sustainable livestock systems should indeed be environmentally friendly, economically viable for farmers, and socially acceptable, notably for anim...

The diversity of beef cattle production systems in terms of diet, manure management and building design results in variation in greenhouse gas (GHG) emissions and the opportunities to reduce them. Within this context, we studied the effect of the varying proportions of concentrate (37–85% of DM) in the diet of Belgian Blue heifers on CH4 and N2O em...

Decruyenaere V, Clément C, Agneessens R, Losseau C & Stilmant D (2011) Development of near‐infrared spectroscopy calibrations to quantify starch and soluble sugar content in the roots of Rumex obtusifolius. Weed Research 52, 1–5. SummaryThe long‐term objective of non‐chemical measures applied to control a perennial weed is to limit its vigour and r...

The control of Rumex obtusifolius L. (broad-leafed dock) is very important in organic farming systems. Indeed, concerns about managing this weed without the use of herbicides is one of the major factors limiting the uptake of these systems by conventional farmers. Against this background, we analyzed the impact of two management practices on the de...

The control of Rumex obtusifolius, even with the use of herbicides, is difficult in permanent grasslands where R. obtusifolius reduces both productivity and nutritive value of herbage. It is important to find alternative approaches to managing R. obtusifolius. Two greenhouse experiments were conducted to compare the impact of different cutting freq...

In view of the development of renewable energies, certain forage crops may be contemplated as sources of them. Such an option is under the influence of several factors, related or not to agriculture, which are of interest to analyse at the outset. The three main ways of producing energy from the bio-mass (combustion, bio-methanization and through s...

In a grassland farming system, a very marked water shortage in summer may affect considerably the production of the pastures, as happens in several Belgian regions. How then can mown and grazed permanent pastures be improved and renovated ? The direct seeding of associations containing Lucerne shows interesting prospects. In trials situated in Fame...

In extensive forage-producing regions, especially those in which a remarkable bio-diversity has been recognized by the Natura 2000 network, it is possible to find a convergence of environmental objectives with agricultural interests and with the development of the land. This however requires a patient endeavour of collaboration among the various ag...

In grazed grasslands, the heterogeneity of urine patches distribution needs adapted sampling scheme in order to evaluate N-NO 3- leaching risks. In such context, the aim of this paper is to define the accuracy that could be expected from the sampling scheme applied in this agro-ecosystem (one average sample including 30 core samples taken in the 0-...

At present, the dairy cow's standard of nitrogen production in Walloon region is 90 kg per year. This standard is used to calculate the "soil link rate" of farms, a balance between the organic nitrogen to be spread on land and the quantity legally authorized considering grassland and arable land area. This standard is appreciably lower than that fi...

Sampling scheme to quantify nitrogen leaching risk in grazed grassland: which scheme for which accuracy? In grazed grasslands, the heterogeneity of urine patches distribution needs adapted sampling scheme in order to evaluate N-NO3 - leaching risks. In such context, the aim of this paper is to define the accuracy that could be expected from the sam...

Towards a revison of the dairy cow’s standard for nitrogen production: justification and what are consequences for soil link rate of dairy farms. At present, the dairy cow’s standard of nitrogen production in Walloon region is 90 kg per year. This standard is used to calculate the “soil link rate” of farms, a balance between the organic nitrogen to...

Cellulose, hemicelluloses, lignin, and ash contents in various lignocellulosic crops for second generation bioethanol production. Various green energy crops are available for the production of renewable energy vectors such as second generation bioethanol. The efficiency of the energy recovery potential of these lignocellulosic crops depends on the...

Defining alternatives for non-renewable energy sources constitutes a priority to the development of our societies. One of these alternatives is biofuels production starting from energy crops, agricultural wastes, forest products or wastes. In this context, a "second generation" biofuels production, aiming at utilizing the whole plant, including lig...

The efficiency of the energy recovery potential of lignocellulosic crops as solid biofuel depends on various characteristics. One of the main characteristics in this field is the higher heating value. It is defined as the amount of heat emitted by the combustion of a fuel, including the heat coming from the condensation of the water vapor. Its valu...

Fonio millet (Digitaria exilis), a small-grained cereal, plays an important role in food security in West Africa. As part of efforts to increase its productivity, we studied the effects of moderate levels of nitrogen (0, 15.0 and 30.0 kg N ha(-1)), phosphorus (0, 6.6 and 13.2 kg P ha(-1)) and potash (0, 12.5 and 25.0 kg K ha(-1)) fertilizers under...

Biofuels can offer an alternative to fossil fuels in the context of climate change and fossil reserves depletion. Plant biomass consists mainly of structural (cell wall) polysaccharides, but contains also reserve polysaccharides (starch and polyfructans) and soluble sugars, that can be converted by micro-organisms. We examined the feasibility of a...