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Judged by their negative nutrient balances, low soil cover and low productivity, the predominant agro-pastoral farming systems in the Sudano-Sahelian zone of West Africa are highly unsustainable for crop production intensification. With kaolinite as the main clay type, the cation exchange capacity of the soils in this region, often less than 1 cmolc kg−1soil, depends heavily on the organic carbon (Corg) content. However, due to low carbon sequestration and to the microbe, termite and temperature-induced rapid turnover rates of organic material in the present land-use systems, Corg contents of the topsoil are very low, ranging between 1 and 8 g kg-1 in most soils. For sustainable food production, the availability of phosphorus (P) and nitrogen (N) has to be increased considerably in combination with an improvement in soil physical properties. Therefore, the adoption of innovative management options that help to stop or even reverse the decline in Corg typically observed after cultivating bush or rangeland is of utmost importance. To maintain food production for a rapidly growing population, targeted applications of mineral fertilisers and the effective recycling of organic amendments as crop residues and manure are essential. Any increase in soil cover has large effects in reducing topsoil erosion by wind and water and favours the accumulation of wind-blown dust high in bases which in turn improves P availability. In the future decision support systems, based on GIS, modelling and simulation should be used to combine (i) available fertiliser response data from on-station and on-farm research, (ii) results on soil productivity restoration with the application of mineral and organic amendments and (iii) our present understanding of the cause-effect relationships governing the prevailing soil degradation processes. This will help to predict the effectiveness of regionally differentiated soil fertility management approaches to maintain or even increase soil Corg levels.

Growing concerns over the use of limited fossil fuels and their negative impacts on the ecological niches have facilitated the exploration of alternative routes. The use of conventional plastic material also negatively impacts the environment. One such green alternative is polyhydroxyalkanoates, which are biodegradable, biocompatible, and environmentally friendly. Recently, researchers have focused on the utilization of waste gases particularly those belonging to C1 sources derived directly from industries and anthropogenic activities, such as carbon dioxide, methane, and methanol as the substrate for polyhydroxyalkanoates production. Consequently, several microorganisms have been exploited to utilize waste gases for their growth and biopolymer accumulation. Methylotrophs such as Methylobacterium organophilum produced highest amount of PHA up to 88% using CH4 as the sole carbon source and 52–56% with CH3OH. On the other hand Cupriavidus necator, produced 71–81% of PHA by utilizing CO and CO2 as a substrate. The present review shows the potential of waste gas valorization as a promising solution for the sustainable production of polyhydroxyalkanoates. Key bottlenecks towards the usage of gaseous substrates obstructing their realization on a large scale and the possible technological solutions were also highlighted. Several strategies for PHA production using C1 gases through fermentation and metabolic engineering approaches are discussed. Microbes such as autotrophs, acetogens, and methanotrophs can produce PHA from CO2, CO, and CH4. Therefore, this article presents a vision of C1 gas into bioplastics are prospective strategies with promising potential application, and aspects related to the sustainability of the system.

Nowadays, as environmental awareness is key issue among researchers, scientific community is looking for natural materials as they are biodegradable, low cost, eco-friendly and also safe for health. Researchers and academicians have found many natural fibers and studied their properties for their sustainable applications in various possible sectors, and studies are also going on. So, in that context several natural fiber like jute, sisal, banana, pineapple, flax, hemp, kenaf, bamboo, cornstalk waste, coir, etc. have been successfully utilized as a reinforcing material in polymer composites by replacing man made synthetic fiber. Apart from traditional natural fibers, scientific community is also looking for locally available natural fibers across the globe in different geographical locations for successful reinforcement in polymer matrix. This will not only decrease burden on traditional fibers and but also at the same time it would be helpful to enrich the rural economy. Natural fiber based composites can be used in different areas such as auto motive industry, construction industry, sports industry and food industry. This study is related with extraction, characterization, surface treatment thermal analysis and activation energy of different uncommon natural fibers available at different geographical locations worldwide. The purpose of this study is to provide a comprehensive knowledge on extraction techniques, treatment methodologies, and properties of these uncommon natural fibers so that these novel materials can be utilized efficiently as a reinforcing material in different polymer matrix. Discussions on traditional natural fibers like Bagasse, Wheat straw, Coir, Pineapple, Banana etc. have been compiled extensively in various review papers but compilation on these new uncommon natural fibers is rare. Thermal analysis along with activation energy evaluation is another aspect which has been given emphasis in discussion because this is also a very important examination to evaluate the thermal stability of these natural fibers.

The levels of production diseases (PD) and the cow replacement rate are high in dairy farming. They indicate excessive production demands on the cow and a poor state of animal welfare. This is the subject of increasing public debate. The purpose of this study was to assess the effect of production diseases on the economic sustainability of dairy farms. The contributions of individual culled cows to the farm’s economic performance were calculated, based on milk recording and accounting data from 32 farms in Germany. Cows were identified as ‘profit cows’ when they reached their individual ‘break-even point’. Data from milk recordings (yield and indicators for PD) were used to cluster farms by means of a principal component and a cluster analysis. The analysis revealed five clusters of farms. The average proportion of profit cows was 57.5%, 55.6%, 44.1%, 29.4% and 19.5%. Clusters characterized by a high proportion of cows with metabolic problems and high culling and mortality rates had lower proportions of profit cows, somewhat irrespective of the average milk-yield per cow. Changing the perception of PD from considering it as collateral damage to a threat to the farms’ economic viability might foster change processes to reduce production diseases.

La primera biorrefinación con lignina del álamo nórdico para producir fibras de celulosa podría desplazar la producción de algodón en tierras agrícolas Al cruzar Populus trichocarpa 3 P. trichocarpa de una población distante, se obtuvieron álamos híbridos que pueden crecer rápidamente en tierras marginales en climas del norte. Estos híbridos pueden transformarse mediante fraccionamiento catalítico reductor para producir una fibra textil deslignificada que puede ser un sustituto del algodón, así como un biocombustible alimentado con lignina en el rango de gasolina-aviación-diesel. La sostenibilidad de esta cadena de valor fue evaluada por LCA y mostró beneficios sustanciales en términos de uso de agua en comparación con la producción de algodón. Le bioraffinage en lignine du peuplier nordique pour produire des fibres de cellulose pourrait déplacer la production de coton sur les terres agricoles En croisant Populus trichocarpa 3 P. trichocarpa d'une population éloignée, des peupliers hybrides ont été obtenus qui peuvent croître rapidement sur des terres marginales dans les climats nordiques. Ces hybrides peuvent être transformés par fractionnement catalytique réducteur pour donner une fibre textile délignifiée qui peut remplacer le coton ainsi qu'un biocarburant ligninérisé dans la gamme essence-aviation-diesel. La durabilité de cette chaîne de valeur a été évaluée par LCA et a montré des avantages substantiels en termes d'utilisation de l'eau par rapport à la production de coton. Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands By crossing Populus trichocarpa 3 P. trichocarpa from a distant population, hybrid poplar trees were obtained that can grow rapidly on marginal lands in northern climates.These hybrids can be transformed by reductive catalytic fractionation to yield a delignified textile fiber that can be a substitute for cotton as well as a ligninderived biofuel in the gasoline-aviation-diesel range.The sustainability of this value chain was evaluated by LCA and showed substantial benefits in terms of water use compared with cotton production. يمكن للتكرير الحيوي الأول لليجنين للحور الشمالي لإنتاج ألياف السليلوز أن يحل محل إنتاج القطن في الأراضي الزراعية من خلال عبور Populus trichocarpa 3 P. trichocarpa من مجموعة سكانية بعيدة، تم الحصول على أشجار الحور الهجينة التي يمكن أن تنمو بسرعة على الأراضي الهامشية في المناخات الشمالية. يمكن تحويل هذه الهجينة عن طريق التجزئة التحفيزية المختزلة لإنتاج ألياف نسيج منزوعة الكرامة يمكن أن تكون بديلاً عن القطن بالإضافة إلى وقود حيوي خفيف في نطاق البنزين والطيران والديزل. تم تقييم استدامة سلسلة القيمة هذه من قبل LCA وأظهرت فوائد كبيرة من حيث استخدام المياه مقارنة بإنتاج القطن.

Economic growth in developing countries accelerated waste generation, and Thailand also is experiencing issues related to increased waste generation and improper waste management. The country’s domestic waste utilization is only 20%–26%. Efficient waste management and increased quantity of waste utilization is possible only by overcoming problems and constraints in reverse logistics (RL) systems in Thailand. To address these issues and constraints, this study aims to focus the investigation on the current practices in the RL systems. The study was conducted in Bangkok and its vicinity. An integrated approach of qualitative and quantitative methods was employed to investigate the systems’ and stakeholders’ characteristics and to explore the factors influencing and constraining RL practices. Data were gathered through: (1) existing literature and in-depth interviews of key stakeholders involved in RL; and (2) a questionnaire survey of 98 managers of separation centers (SCs) probing their practices and studying the factors influencing those practices. The findings showed that RL systems can be separated into three levels, i.e., downstream, middle stream and upstream. SCs are key stakeholders in RL of waste management, and they collect waste from downstream, manage waste in a systematic way and send it upstream. The factors influencing and the barriers in the flow of recyclable waste are related to environmental, economic and social aspects. The analysis shows that waste managed by a cooperative-like franchise of SCs perceived that their practices were more efficient than those of a non-franchise practices. Additionally, these SCs have more bargaining power with waste buyers and sellers to set prices in the RL system. The constraints in RL practice are related to finance, market, labor, management/technology and legal issues.

Biofloc technology (BFT) is gaining traction as a strategic aquaculture tool for boosting feed conversions, biosecurity, and wastewater recycling. The significant aspect of BFT is aquaculture with highest stocking density and minimal water exchange. It not only improves the water quality of a system by removing inorganic nitrogen from wastewater but also serves as a suitable feed supplement and probiotic source for cultured species. This technology is commonly used for shrimp and tilapia culture and can be used for both semi-intensive and intensive culture systems. Biofloc, when combined with formulated diets, forms a balanced food chain that improves growth performance. Nutrients in this system are continuously recycled and reused and form an efficient alternative system in aquaculture. In addition to the reduction in water exchange, it is also considered as a bio-security measure, since it prevents entry of disease from outside sources. Aquamimicry is an innovative concept that simulates natural estuarine conditions by developing copepods that act as supplementary nutrition especially for shrimp culture. The review highlights the process, significance, and development of BFT, its microbial interactions, nutritional value, transition from biofloc to copefloc, and concept of aquamimicry to sustainably improve aquaculture production.