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Two studies conducted in Guadeloupe (West Indies) and Réunion (Indian Ocean) islands were designed to investigate the benefits of producing sugarcane as an energy crop and to assess the influence of agroclimatic factors on energy efficiency, respectively. In this context, it is essential to know the low heating value of the dry above-ground biomass (LHVd, MJ/kg) and its energy yield (EY, MJ/m2) in order to select the best varieties and set up a payment method for growers. Eighteen Poaceae (sugarcane and Erianthus) cultivars were compared under wet tropical environmental conditions in Guadeloupe. Three sugarcane cultivars were studied in four contrasting environments in Réunion. The partition sampling and biomass measurement procedures were identical at both locations. Low heating value (LHV) predictions were achieved using near-infrared reflectance spectroscopy (NIRS) after specific calibration (Guadeloupe), or arithmetically after lignocellulosic compound prediction (Réunion). In both studies, LHV variability was very low and slightly dependent on the site, cultivar and above-ground biomass components (millable stalks and tops, and green and dead leaves). Considering the overall dry above-ground biomass (DAB, kg/m2), the LHVd was calculated by averaging 159 samples (mean 16.65 MJ/kg) in Guadeloupe and 315 samples (mean 16.45 MJ/kg) for Réunion. An excellent linear relationship between the DAB and its EY, regardless of cultivar, age and environment, was found (n = 474 and R² = 0.99). Sugarcane energy content assessment could thus be simplified by measuring the DAB, while enabling development of a faster method of payment for growers based on the DAB measurement and the correlation between DAB and EY. Finally, the findings of this study should allow growers to rapidly determine the commercial value of their sugarcane crops, and also enable purchasers to assess the amount of recoverable energy. (Résumé d'auteur)

Abstract This article reviews the current status of research on urban green and blue infrastructure (GBI) in developing countries. We critically analyzed a total of 283 papers addressing urban GBI in selected developing countries in Africa, Asia, Latin America and the Caribbean (LAC), published between 2015 and 2019. The review aimed to a) analyze publication trends and typologies of urban GBI; b) identify innovative problem-solving measures using urban GBI, and c) understand priorities, differences and similarities in the deployment of urban GBI between the regions. The article identifies a growing interest in the urban GBI concept in the Global South, with a focus on local sustainable development. Urban GBI aims to address issues of urban greenery, land use policies, food security and poverty alleviation. There is a large variation in the number of articles across regions, with Asia, and particularly China, as the subject having a much larger number of publications when compared to LAC and Africa. We found that the focus of research topics varied between regions, reflecting regional development needs, so that urban agriculture research predominated in Africa, and green spaces and parks in Asia and LAC. GBI is still not implemented as a low-impact development or innovative strategy, except in China, where researchers have examined several cases of systemic GBI use for addressing urban issues. More recently, studies began exploring the linkages between nature and cities in light of global environmental issues such as biodiversity loss and climate change. We conclude with recommendations to further examine empirical evidence of urban GBI deployment and its outcomes in the Global South, that could contribute toward conceptualizing natural resource management in a multi-scalar, multi-dimensional, and multidisciplinary framework.

Agroforestry is considered a sustainable form of land management that optimizes the use of natural resources (nutrients, radiation, water). Agroforestry is defined as the deliberate integration of woody vegetation with agricultural activities in the lower story. It provides a higher biomass production per unit of land, while providing more ecosystem services than woody-less agricultural lands, such as the reduction of soil erosion and nitrogen leaching, and increase carbon sequestration and landscape biodiversity. The objective of this paper is to evaluate the past and current European Union Common Agricultural policies aiming at promoting the afforestation or reforestation of lands, as the introduction of trees can be seen as a first step to carry out agroforestry practices in former agricultural or forest lands. Agroforestry was a traditional land use system in Europe before modern times. However, before the sixties land intensification and consolidation destroyed millions of trees all over Europe. On the contrary, some good examples of agroforestry promotion are found in Eastern European countries in order to reduce the effect of extreme events such as winds, flooding at the beginning and mid of the last century. In Western European countries, the introduction of trees in the land has been promoted by agroforestry, afforestation and reforestation at the end of the last century. Afforestation of agricultural lands have been the most successful CAP measure (over 1 million hectares) while agroforestry measures were not extensively adopted which may be explained by the funds associated to afforestation measure which compensated the losses of income 15 or 20 years in afforested lands. Agroforestry was poorly adopted in the CAP 2007-2013, having a better success in the CAP 2014-2020 due to the recognition of woody vegetation and the compensation of 5 years given for maintenance once agroforestry is established. However, policy rules ensuring Pillar I payment when agroforestry measure is adopted such as a management plans ensuring that maximum tree density (100 trees per hectare) is not reached, should be pursued.

The experiment determined the technical and financial efficiency of five storage techniques, specifically designed for SRF poplar chips stored at the farm site in small (20 m3) piles. The treatments on test were: uncovered storage, storage under a temporary roof structure, cover under a semi-permeable fleece sheet, cover under two types of plastic sheet (i.e. white and black). Each treatment was replicated 3 times. Researchers monitored temperature and moisture content trends inside the piles, and determined dry matter losses at the end of the 170 days storage period. In general, piles under plastic cover presented opposite trends compared to all other piles. They acquired moisture rather than losing it, and showed gradual temperature trends instead of a typical peak-and-drop behaviour. Dry matter losses varied from 5.1% to 9.8%, and were highest for the uncovered treatment, and lowest for the plastic cover treatment. Under the conditions of north-western Italy, uncovered storage was a cost-effective option. Protecting the piles with some cover incurred more cost than it saved, resulting in a higher storage cost per unit energy. Although more expensive, sheltering the piles under a simple roof structure offered the benefit of a higher reduction of moisture content, which may turn the chips into a higher quality fuel. Of course, these results were closely related to the Southern European climate, and the specific year of the test. Occasional wetter years may overturn these results. © 2013 Elsevier Ltd. All rights reserved.

Abstract In the past 10 years, 90% of cassava starch factories in Thailand have switched from fuel oil to renewable biogas, to cover part of their energy needs. The environmental benefits of switching to biogas have not been assessed quantitatively. To alleviate this, this study assessed 100-year greenhouse gas (GHG) emissions, or carbon footprint (CF), of cassava starch production for four factories in Thailand. Key results demonstrate that biogas reduces the carbon footprint of the Thai cassava starch industry as a whole by 0.9–1.0 million tons CO2eq/year, and highlight methodological precautions to collect LCI data and allocate GHG emissions between co-products with high moisture contents. The system boundaries included farm stage (production of cassava roots), transportation to factory and processing into native starch. The functional unit (FU) was one ton of native cassava starch at 13% water content. Biogas produced from the factory wastewater (95–200 m3/FU) was the main source of thermal energy for starch drying, and for on-site electricity production when excess biogas was available. The total CF of cassava starch was in the range 609–966 kg CO2eq/FU. Agricultural production contributed 60% of the carbon footprint, mainly from the use of nitrogen fertilizers. GHG emissions of root production varied widely due to (1) the diversity of farming practices even within a small radius (50 km), and (2) different agricultural yields in different regions. The contribution of the factory stage to the carbon footprint depended on the use of electricity, biogas and other fuels, ranging from 217 to 342 kg CO2eq/FU. Allocation rules such as wet weight or dry weight basis allocations affected the results markedly.

Vineyards cover about eight millions of hectares worldwide and their annual pruning generates a large amount of ligno-cellulosic biomass, potentially available for industrial and energy use. Commercial pruning residue harvesters are now available, which may allow cost-effective recovery. The study aimed at determining the quantity and the quality of pruning residues potentially derived from vineyard management. Data were obtained from 17 fields in Northern and Central Italy. Fields were harvested with seven different machines. The experimental design adapted to the necessities of field trials, but was adequate for testing the main sources of variability. Net residue yield varies around 1 oven dry tonne per hectare, with minor differences between grape varietals and harvesting technologies. Losses are still high, and are generally related to ineffective management techniques. Moisture content at harvest varies between 40% and 45%, whereas the higher heating value is slightly lower than that of forest fuels. Comminuted vineyard residues are unsuitable for firing residential boilers, due to the frequent presence of oversize and/or undersize particles. The application of pesticides does not result in any significant contamination with noxious chemicals, because these products are almost completely weathered before residues are recovered. In wine-producing regions, the recovery of vineyard pruning residue may represent a substantial source of industrial bio-fuel. © 2011 Elsevier Ltd.

Abstract In many African countries, the upswing in oil prices is one factor that favours the adoption and implementation of a national biofuel policy. This trend has a major impact on state budgets and domestic trade balances, while also limiting the access of rural inhabitants to modern energy services. Contribution of biofuels in stabilizing the energy sector, influences ongoing negotiations on the global dynamics of climate change, the reduction in greenhouse gas (GHG) emissions and sustainable development. The question of biofuels as an alternative energy thus depends on international, national and local considerations. Biofuels represent opportunities, e.g., energy independence and security, new national income and employment sources, as well as potential food security problems. African policy makers therefore need to make the right choices to guide the development of biofuel production and use. This article aims to support the development of a biofuel policy by reviewing the latest technical, economic, environmental and social knowledge so as to be able to evaluate the potential and limits of biofuels in Burkina Faso.

AbstractEstimates on impacts of biofuel production often use models with limited ability to incorporate changes in land use, notably cropping intensity. This review studies biofuel expansion between 2000 and 2010 in Brazil, the USA, Indonesia, Malaysia, China, Mozambique, South Africa plus 27 EU member states. In 2010, these countries produced 86 billion litres of ethanol and 15 billion litres of biodiesel. Land use increased by 25 Mha, of which 11 Mha is associated with co‐products, i.e. by‐products of biofuel production processes used as animal feed. In the decade up to 2010, agricultural land decreased by 9 Mha overall. It expanded by 22 Mha in Brazil, Indonesia, Malaysia, and Mozambique, some 31 Mha was lost in the USA, the EU, and South Africa due to urbanization, expansion of infrastructure, conversion into nature, and land abandonment. Increases in cropping intensity accounted for 42 Mha of additional harvested area. Together with increased co‐product availability for animal feed, this was sufficient to increase the net harvested area (NHA, crop area harvested for food, feed, and fiber markets) in the study countries by 19 Mha. Thus, despite substantial expansion of biofuel production, more land has become available for non‐fuel applications. Biofuel crop areas and NHA increased in most countries including the USA and Brazil. It is concluded that biofuel expansion in 2000–2010 is not associated with a decline in the NHA available for food crop production. The increases in multiple cropping have often been overlooked and should be considered more fully in calculations of (indirect) land‐use change (iLUC). © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd