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Tropical country economies are still based on agro-industries and wood industries. These industries generate a urge amount of waste which create damage to the environment when they are incinerated. In the same time conventional energies and technologies hardly cover their energy requirements. The rational use of these residues through biomass energy technology would be an appropriate solution. The scope of this work has consisted in the setting up of a simple decision making methodology adapted to tropical country economies. The economic framework of the Asean countries has been selected as case study. Figures show that agro- based industries offer a large potential of renewable energy sources. It has also enlighten that due to the economic growth of the region, the energy demand is skyrocketing with subsequent supply problems. Meanwhile, the different proven biomass energy technologies available are able to match with the energy requirement of the endusers and the technical constraints of the biofuel. Due to the number of technical options, decision makers are facing a choice problem. It consist in the selection of the best technology available between competing and alternative solutions. This choice constitute a real deadlock to biomass energy technology dissemination. Therefore, a decision making methodology tool adapted to tropical countries is proposed. Technical, micro-economic and also macro-economic criteria have been considered and a computer application developed. Seven technologies, for heat generation, power generation with or without cogeneration, using sugar cane residues, rice husk, wood wastes, palm oil residues in substitution to conventional technologies (coal, gas and petroleum products fired) are compared and ranked. Criteria considered are : cost/benefit ratio, environmental benefit vis a vis greenhouse gas emission impact (CO, C02, NOx, S02, COV and total C02 equivalent). Results have been validated through figures gathered from the demonstration projects supported by the European Union in Asean and will be discussed in the present paper. (Résumé d'auteur)

Smallholder natural rubber area covers 3 milions ha in Indonesia, among it 2 million ha are rubber agroforests (locally called "jungle rubber") in Sumatra and Kalimantan. These rubber agroforests are the most widespread complex agroforestry system in Indonesia combining production (however productivity is low) and environmental benefits, as well as a certain biodiversity conservation, due to agroforestry practices. Beside being the key to Indonesia's future competitive advantage in natural rubber production, a workable strategy to raise productivity of these rubber smallholders also could play an important role in both poverty alleviation and environment conservation. The "jungle rubber" system is a low-input agroforestry system in which rubber competes with the regrowth of the natural forest. The system is inexpensive and requires little labour to establish and maintain. From the viewpoint of environmental conservation, a rubber jungle with a planting scheme similar to a secondary forest has a positive value, because its habitat is good for environmental conservation. Its good hydro-orology characteristics will resist erosion and enrich plant biodiversity. It positively supports the "green movement", which has acquired a lot of interest from big industrial countries who are also the major consumers of natural rubber. The Rubber Association of Indonesia (GAPKINDO) in collaboration with the International Center of Research in Agroforestry (ICRAF), Southeast Asia Program and CIRAD-CP-TERA (France), have been conducting o -farm trials with participatory approach and economic analysis of improved smallholder agroforest system, funded by a grant from USAID, as well as socio economic surveys in order to identify pros and cons of RAS technology adoption (improved Rubber Agroforestry Systems) . The network has been developed in West Kalimantan (Sanggau and Sintang), Jambi (Muara Bungo) and West Sumatra (Pasaman). The objective is to manage the rubber jungles more intensively by planting high yielding clones which are suitable for the rubber jungle system with different degrees of intensification in inputs and labour. Hard-wood and fruit trees, pulp trees fro shading against Imperara, annual crops and various type of covercrops are combined with rubber trees, in different trials, to identify the best and more adoptable combinations as well as maintaining a certain level of biodiversity. Biodiversity is considered as an interesting by-product with no cost . The secondary forest regrowth in between rubber lines is even considered as a labour saving pratice and the best anti Imperata strategy. RAS systems aim also to rehabilitate Imperata grasslands. Rubber Agroforestry systems do have both economically and environmental sustainability. (Résumé d'auteur)

Lalang (Imperata cylindrica) is known to be the most noxious weed in the tropics and a major constraint for food and tree crop development. Estates developed technologies to suppress Imperata using chemical herbicides and promoting the establishment of legume cover crops (LCC). These technologies have been also used in assisted smallholder schemes but such methods are too costly to be widely adopted by farmers in self-help development. In SRAP (Smallholder Rubber Agroforestry Project) a different approach for the suppression of Imperata was tested. The association of various cover crops, shrubs and fast growing trees (FGT) with rubber is used to control Imperata by shading. The system was called "Rubber Agroforestry System-type 3" (RAS 3). All experiments were conducted in smallholders' fields with participatory approach. The association of different species with rubber aims to assess the ability of various plants to control Imperata and to evaluate the impact of the association on rubber growth. Legume shrubs like Flemingia congesta were found effective to control Imperata as the rubber growth in RAS type-3 was found similar to growth with conventional technologies using Pueraria phaseoloides after 3 years of experiment. Fast Growing Trees (FGT) like Acacia mangium, Acacia Crassicarpa, Paraserianthes falcalaria, Gmelina arborea did not affect rubber growth after a period of 42 months. Before experiment establishment, all the plots were infested by Imperata but during trial implementation, flora composition changed and some plots were invaded by Chromolaena odorata and Melastoma affine reducing Imperata extend. Acacia mangium was founded as the most effective tree to suppress Imperata by shading. As Acacia trees become competitive to rubber at the age of 42 months, they must be pruned or felled to prevent a depressive effect on rubber growth due to competition for light. Fast Growing Trees (FGT) associated with rubber can help Imperata control reducing maintenance cost in rubber farms however, the planting pattern of associated trees with rubber must be adapted using wider inter-row if an income from pulpwood sales is expected. (Résumé d'auteur)

Original data for the study: Lí, et al. Subarctic winter-warming promotes soil microbial resilience to freeze-thaw cycles and enhances the microbial carbon-use efficiency. This dataset mainly contains the data showing the legacy effect of field winter warming on the dynamic response of soil microbial growth, respiration, and C-use efficiency during an imposed freezing-thawing perturbation. Six sheets are included in an Excel file named "Open data for WinterWarmingFTW.xlsx" as follows: Figure1. Field temp & moist Table1. Soil variables & PLFAs Figure2. PCA of PLFAs Figure3. Bac & Fung grwoth Figure4. Resp Figure5. FB & CUE

Le BIO-UCF (Bio-Ultracarbofluide) est un produit ternaire composé de charbon végétal, d'eau et de fuel ou gazole. Cette étude présente la production de ce produit, comme carburant liquide de substitution des fuels et du gazole dans les brûleurs et les moteurs diesel. Les tests sont orientés vers la recherche des éléments suivants : production et broyage du charbon, procédé de formulation du mélange, atomisation, caractéristiques d'inflammation et de combustion du BIO-UCF

Cette communication présente un résumé des objectifs du projet RAS (Systèmes Agroforestiers à base d'Hévéa), ainsi que les protocoles des différents types d'essais mis en place dans les 4 systèmes agroforestiers identifiés par le projet

Since in the first and decisive stages of their development, bio-energy potentials are highly dependent on favourable public intervention and its ability to overcome the lock-in effects that maintain the hegemony of conventional fossil energies, bio-energy potentials should not only be quiered in terms of costs and available volumes. Public support for a given bio-energy is all the more legitimate when its future potential can be proved high. For that matter, prospective studies, which include both the techno-economic aspects of a given bio-energy and the economic conditions of its emergence and development, are required. The engineers' and the economists' point of view regarding technical change, must be combined into some hybrid bottom-up top-down models, allowing for the consistency of technological choices at the micro-level with some macro-economic aggregates, namely activity indicators. Central points to be considered are the possible feedback impacts of technlological choices on the macro-economy via changes in the technical coefficient. The role of prices needs special attention in this matter. The hybrid model presented here has been used for a prospective study on bio-energies in Brazil and another on biofuels in France. It essentially consists of the iteratively linked projections of both the input-output table and the energy balance of the economy. We shall describe the modelling methodology, the main hypotheses and "experts sayings" the model relies on, and finally illustrate with some results on biofuels in Brazil (résumé d'auteur)

The kinetics for the main reactions involved in the gasification of biomass are experimentally studied. The reactions concerned are: - devolatilisation (or pyrolysis) of the raw biomass; - oxidation of the raw biomass; - charcoal oxidation (attack by O2); - charcoal gasification (attack by CO2). Three commonly produced forms of biomass, i.e. rice husk, wheat straw and pine bark have been characterised. A bituminous coal has also been studied for reference to more classical fuels. Two reactors have been used. Dynamic Thermo-Gravimetry reproduces the low heating rates present in reactors such as fixed beds or rotary kilns. An entrained flow reactor was used to simulate the high heating rates encountered in fluidised beds, entrained beds and flash processes. Care was taken to remain in conditions where no heat transfer or mass transfer limitation is effective, so that intrinsic kinetic parameters could be determined. Quantitative values for the reaction rates in temperature domains relevant to industrial applications are derived. (Résumé d'auteur)