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Mali is a Sahelian country with a large climatic contrast from North to South. The current climatic and production evolutionary study is focused on the six major agro-climatic cereal production zones ranging from Kayes (400 mm) to Sikasso (>1000 mm) of rainfalls. Climatic data are rainfall records, daily maximum and minimum temperatures from 60 years of the six major synoptic weather observation stations. Data were analyzed on comparing average decades of the two normal periods of 30 years (1951-1980) and (1981-2010). Annual agronomic production data for millet, sorghum, maize and rice are derived from Mali's agricultural statistics base from 1984 to 2013. Main climatic results analyses indicate that climate change resulted in a decrease of 100 mm isohyets between the 2 periods of 30 years. The structure of the rainy season was little changed between these two periods since the average start of the season was delayed by 6 days and the average end date of the season became earlier by 4 days. Maximum temperatures increased significantly from + 0.44°C to + 1.53°C and minimum temperatures significantly increased from + 1.05°C to + 1.93°C in varying way depending on the sites. Statistics of major agronomic food crop production in Mali from 1984 to 2013 indicate an average increase of 985 to 4492 thousand tones, or 22% increase per year. There is a positive upward in saw tooth trend in Malian production from 1984 to 2013. This positive trend is the result of a combination of agricultural extension, agronomic research application and the management of small farmer holder in the Sahel. This evolution needs better study for drawing necessary right conclusions.

Second generational biofuels offer the possibility of using biomass residues such as agricultural or industrial wastes for use in internal combustion engines. However, biochemical and thermochemical conversions to liquid or gaseous fuels require elaborate and expensive pre-treatment facilities. Decreasing the complexity, size and cost of these facilities can alleviate sourcing constraints, increasing implementation in a wide range of applications. Remaining in its original solid form, biomass powder is a simplified biofuel requiring only drying and milling which is technically and economically feasible at a wide range of scale. By exploiting its explosive character, we can operate a standard diesel engine directly on powder for energy generation. The demand for a low-tech biofuel along with advances in milling techniques motivates the idea of using biomass powder in an engine. In this paper we provide experimental proof by operating a diesel engine on fumigated Wheat Straw and Pine Bark dust each for 35 minutes. Emissions, operational performance and combustion data show that biomass powders from agricultural residues should be considered for use as an adaptable technology for existing engine installations. Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 618-621

AbstractRice is the most important food crop in the developing world. For rice production systems to address the challenges of increasing demand and climate change, potential and on‐farm yield increases must be increased. Breeding is one of the main strategies toward such aim. Here, we hypothesize that climatic and atmospheric changes for the upland rice growing period in central Brazil are likely to alter environment groupings and drought stress patterns by 2050, leading to changing breeding targets during the 21st century. As a result of changes in drought stress frequency and intensity, we found reductions in productivity in the range of 200–600 kg/ha (up to 20%) and reductions in yield stability throughout virtually the entire upland rice growing area (except for the southeast). In the face of these changes, our crop simulation analysis suggests that the current strategy of the breeding program, which aims at achieving wide adaptation, should be adjusted. Based on the results for current and future climates, a weighted selection strategy for the three environmental groups that characterize the region is suggested. For the highly favorable environment (HFE, 36%–41% growing area, depending on RCP), selection should be done under both stress‐free and terminal stress conditions; for the favorable environment (FE, 27%–40%), selection should aim at testing under reproductive and terminal stress, and for the least favorable environment (LFE, 23%–27%), selection should be conducted for response to reproductive stress only and for the joint occurrence of reproductive and terminal stress. Even though there are differences in timing, it is noteworthy that stress levels are similar across environments, with 40%–60% of crop water demand unsatisfied. Efficient crop improvement targeted toward adaptive traits for drought tolerance will enhance upland rice crop system resilience under climate change.

Dams can produce electricity and ensure water security, but at the same time they radically alter the hydrological regime of rivers with significant consequences for the economic and environmental welfare of the region in which they are located. Cost-benefit analysis (CBA) is currently the most frequently used framework for the economic evaluations of dams. Changes at different time scales influence the economic appraisal of dams. However, change and adaptation at both the operational and the structural level are often not included in the CBA evaluation. Not including change and adaptation limits the realistic estimation of cost and benefits, and the appreciation of resilient solutions that offer satisfactory responses for a large set of future scenarios. In this paper we consider the specific features of large dams in an African context, and identify methods for an economic evaluation that takes into account for change and adaptation at both the operational and the structural scales, as well as their interplay. These methods are then applied to the ex-ante evaluation of a system of existing dams on the Senegal River Valley. Results indicate the economic potential of the dams under changing conditions, for both adaptive and non-adaptive reservoir operation strategies.

The hypothesis made is that thermal resistance of sorghum and miscanthus stem pieces taken at well-defined positions of the stem is simply related to their biochemical composition. For miscanthus, two different genotypes and two internode levels were selected. For each region, the stem was divided into three radial layers. For sorghum, two different genotypes were selected and the stem was divided into the same three radial layers. The results show that the thermal analysis is only sensitive to very large variations of compositions. But aside of such large composition differences, it is impossible to correlate thermal effects to biochemical composition even on very small size, well-identified pieces of plant materials. The interplay between sugar-based components, lignin and minerals is totally blurring the thermal response. Extreme care must be exercised when willing to explain why a given plant material has a thermal behaviour different of another plant material.

Agroforestry systems (AFS) are complex to model mainly due to the high spatial variability induced by the shade trees. Recently, the microclimate and lighf heterogeneity issue in AFS has been addressed using the 30 ecophysiological process-based model MAESPA (Charbonnier et al., 2013; Vezy et al., 2018). MAESPA surpassed the classical sun/shade dichotomy in AFS (Charbonnier et al., 2014) and provided continuous maps of e.g. available light, light-use~ fficiency and canopy temperature within Coffea Agroforestry Systems (GAS). A step further was to design a crop model for Coffea grown under agroforestry that would benefit from this continuum to estimate ecosystem services on the long term and under climate change scenarios. We designed DynA_Cof, a new process-based growth and yield model to compute plot-scale net and gross primary productivity, carbon allocation, growth, yield, energy, and water balance of GAS according to shade tree species and management, while accounting for fine-scale spatial effects using MAESPA metamodels (Figure 1). DynA_Cof satisfactorily simulated the daily plot-scale gross primary productivity (RMSE= 1.69 gc m-2 d-1 on 1562 days) and the energy and water balances (RMSE: AET = 0.63 mm d-1 , H= 1.27 MJ m-2 d-1, Rn= 1.98 MJ m-2 d-1) compared to measurements from an eddy-flux tower in Aquiares (Costa Rica) and also the NPP for above and below-ground organs, coffee bean yield and shade tree wood production compared to a comprehensive database from this site.

The vulnerability of rural communities to climate variability and change in developing countries is widely recognized. However, the question of what factors drive their vulnerability remains subject to different interpretations. This study explored the perceptions of local key informants on the factors influencing the vulnerability of forest communities to droughts and excessive rains in five contrasting socio-ecological zones of the Congo Basin forest. Results from the local level were discussed by national stakeholders. The analysis showed that people agreed on the positive effect of most community assets (physical, natural, human, social and financial) on vulnerability reduction. Diverging views arose with regard to the effects of population density and institutions on vulnerability, as well as to whether the dependence of communities on forest products increased vulnerability. The perceptions of local respondents depended on local contexts and the roles of the respondents in communities. The divergent...

Tropical forests harbor the greatest terrestrial biodiversity and provide various ecosystem services. The increase of human activities on these forests, among which logging, makes the conservation of biodiversity and associated services strongly dependent on the sustainability of these activities. However the indicators commonly used to assess the impact of forest exploitation, namely species richness and biomass, provide a limited understanding of their sustainability. Here, we assessed the sustainability of common forest exploitation in the Guiana Shield studying the recovery of two ecosystem services i.e. carbon storage and wood stock, and an ecosystem function i.e. seed dispersal by animals. Specifically, we compared total and commercial biomass, as well as functional composition in seed size of animal-dispersed species in replicated forest plots before and 27 years after exploitation. Species richness is also studied to allow comparison. While species richness was not affected by forest exploitation, total and commercial biomass as well as seed size of animal-dispersed species decreased 27 years after exploitation, similarly to forests affected by hunting. These results show that ecosystem services and function likely did not recover even at the lowest intensity of forest exploitation studied, questioning the sustainability of the most common rotation-cycle duration applied in the tropics.