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Deltas are among the most productive and diverse global ecosystems. However, these regions are highly vulnerable to natural disasters and climate change. Nature-based solutions (Nbs) have been increasingly adopted in many deltas to improve their resilience. Among decision support tools, assessment of ecosystem services (ES) through spatially explicit modelling plays an important role in advocating for Nbs. This study explores the use of the Land Utilisation and Capability Indicator (LUCI) model, a high-resolution model originally developed in temperate hill country regions, to map changes in multiple ecosystem services (ES), along with their synergies and trade-offs, between 2010 and 2018 in the Vietnamese Mekong Delta (VMD). In so doing, this study contributes to the current knowledge in at least two aspects: high-resolution ES modelling in the VMD, and the combination of ES biophysical and economic values within the VMD to support Nbs implementation. To date, this is the highest resolution (5 by 5 m) ES modelling study ever conducted in the VMD, with ~1500 million elements generated per ES. In the process of trialling implementations of LUCI within the VMD’s unique environmental conditions and data contexts, we identify and suggest potential model enhancements to make the LUCI model more applicable to the VMD as well as other tropical deltaic regions. LUCI generated informative results in much of the VMD for the selected ES (flood mitigation, agriculture/aquaculture productivity, and climate regulation), but challenges arose around its application to a new agro-hydrological regime. To address these challenges, parameterising LUCI and reconceptualising some of the model’s mechanisms to specifically account for the productivity and flood mitigation capability of water-tolerant crops as well as flooding processes of deltaic regions will improve future ES modelling in tropical deltaic areas. The ES maps showed the spatial heterogeneity of ES across the VMD. Next, to at least somewhat account for the economic drivers which need to be considered alongside biophysical valuations for practical implementations of ES maps for nature-based solutions (Nbs) in the upstream VMD, economic values were assigned to different parcels using a benefit transfer approach. The spatially explicit ES economic value maps can inform the design of financing incentives for Nbs. The results and related work can be used to support the establishment of Nbs that ultimately contribute to the security of local farmers’ livelihoods and the sustainability of the VMD.

Background On-going global climate change poses a serious threat for natural populations unless they are able to evolutionarily adapt to changing environmental conditions (e.g. increasing average temperatures, occurrence of extreme weather events). A prerequisite for evolutionary change is within-population heritable genetic variation in traits subject to selection. In relation to climate change, mainly phenological traits as well as heat and desiccation resistance have been examined for such variation. Therefore, it is important to investigate adaptive potential under climate change conditions across a broader range of traits. This is especially true for life-history traits and defences against natural enemies (e.g. parasites) since they influence organisms’ fitness both directly and through species interactions. We examined the adaptive potential of fitness-related traits and their responses to heat waves in a population of a freshwater snail, Lymnaea stagnalis. We estimated family-level variation and covariation in life history (size, reproduction) and constitutive immune defence traits [haemocyte concentration, phenoloxidase (PO)-like activity, antibacterial activity of haemolymph] in snails experimentally exposed to typical (15 °C) and heat wave (25 °C) temperatures. We also assessed variation in the reaction norms of these traits between the treatments. Results We found that at the heat wave temperature, snails were larger and reproduced more, while their immune defence was reduced. Snails showed high family-level variation in all examined traits within both temperature treatments. The only negative genetic correlation (between reproduction and antibacterial activity) appeared at the high temperature. However, we found no family-level variation in the responses of most examined traits to the experimental heat wave (i.e. largely parallel reaction norms between the treatments). Only the reduction of PO-like activity when exposed to the high temperature showed family-level variation, suggesting that the cost of heat waves may be lower for some families and could evolve under selection. Conclusion Our results suggest that there is genetic potential for adaptation within both thermal environments and that trait evolution may not be strongly affected by trade-offs between them. However, rare differences in thermal reaction norms across families indicate limited evolutionary potential in the responses of snails to changing temperatures during extreme weather events. BMC Evolutionary Biology, 17 ISSN:1471-2148

Abstract Xylose is a by-product of lignocellulosic biomass processing for production of second-generation biofuels and could be suitable for bioproduct manufacturing. This paper describes an innovative approach that enables the system to achieve high yielding for hydrogen production. The study compared 4 physicochemical pre-treatments performed in an anaerobic mixed culture (acidic, thermal, acidic-thermal and thermal acidic) to achieve an inoculum with a high-efficiency xylose to hydrogen conversion under mesophilic conditions (30 °C). The acidic pre-treatment was the most efficient to select microorganisms able to produce hydrogen and volatile acid from xylose. Kinetics has shown that acidic pre-treatment had a hydrogen/xylose molar yielding factor of 1.57 (molar base) and a hydrogen maximum production rate of 253 mL H2 h−1. Mass balance considered all possible metabolic pathways using xylose as a substrate. Anaerobic degradation of ethanol was the most active pathway for hydrogen production in all experiments, except for the control. Each pre-treatment performed for the original inoculum resulted in different microbiological profiles, but the genus Clostridium was the most abundant in all assays. Acidic pre-treatment stimulated the growth of organisms from the genera Peptostreptococcaceae, Truepera and Kurthia, which could be related to the better results in hydrogen production found in this condition.

The aqueous extraction of orange peel waste (OPW), the byproduct of the juice extraction process generated annually in massive amounts (21 Mton), yields a carbohydrate-rich liquid fraction, termed orange peel extract (OPE). Several studies highlight that the combination of glycerol, a biodiesel byproduct, with carbohydrate mixtures might boost microbial lipid production. This study performed first a shaken flask screening of 15 oleaginous yeast strains based on their growth and lipid-producing abilities on OPE- and glycerol-based media. This screening enabled the selection of R. toruloides NRRL 1091 for the assessment of the process transfer in a stirred tank reactor (STR). This assessment relied, in particular, on either single- and double-stage feeding fed-batch (SSF-FB and DSF-FB, respectively) processes where OPE served as the primary medium and nitrogen-containing glycerol-OPE mixtures as the feeding one. The continuous supply mode at low dilution rates (0.02 and 0.01 h-1 for SSF-FB and DSF-FB, respectively) starting from the end of the exponential growth of the initial batch phase enabled the temporal extension of biomass and lipid production. The SSF-FB and DSF-FB processes attained high biomass and lipid volumetric productions (LVP) and ensured significant lipid accumulation on a dry cell basis (YL/X). The SSF-FB process led to LVP of 20.6 g L-1 after 104 h with volumetric productivity (r L) of 0.20 g L-1 h-1 and YL/X of 0.80; the DSF-FB process yielded LVP, r L and YL/X values equal to 15.92 g L-1, 0.11 g L-1 h-1 and 0.65, respectively. The fatty acid profiles of lipids from both fed-batch processes were not significantly different and resembled that of Jatropha oil, a vastly used feedstock for biodiesel production. These results suggest that OPE constitutes an excellent basis for the fed-batch production of R. toruloides lipids, and this process might afford a further option in OPW-based biorefinery.

Résumé - La demande commerciale croissante en éthanol a tiré parti des études sur la production d'éthanol de deuxième génération, comme moyen de réduire la dépendance au pétrole et d'élargir la matrice énergétique brésilienne. Dans ce contexte, le présent travail est inséré, qui étudie la production d'éthanol par des fermentations alcooliques de Saccharomyces cerevisiae et Pichia stipitis avec de la bagasse de canne à sucre traitée. La production d'éthanol a été réalisée par un procédé de saccharification et de fermentation simultanée dans un réacteur discontinu avec les complexes enzymatiques bruts et 25% de bagasse de canne à sucre traitée par explosion de vapeur, en utilisant les levures P. stipitis et S. cerevisiae sous forme conjointe et séquentielle, à différents pH, 6,5, 5,5 et 4,5 et temps de fermentation alcoolique. Les meilleurs résultats ont été obtenus avec l'utilisation séquentielle de S. cerevisiae et P. stipitis : productivité de 0,30 g/L.h pour 48 fermentations et concentration en éthanol de 14,7 g/L avec un rendement de 0,294 g d'éthanol/g de cellulose pour 72 h de fermentation. Resumen - La creciente demanda comercial de etanol ha aprovechado los estudios sobre la producción de etanol de segunda generación, como una forma de reducir la dependencia del petróleo y expandir la matriz energética brasileña. En este contexto, se inserta el presente trabajo, que estudia la producción de etanol por fermentaciones alcohólicas de Saccharomyces cerevisiae y Pichia stipitis con bagazo de caña de azúcar tratado. La producción de etanol se realizó por proceso de sacarificación y fermentación simultánea en un reactor por lotes con los complejos enzimáticos crudos y el 25% de bagazo de caña de azúcar tratado por explosión de vapor, utilizando las levaduras P. stipitis y S. cerevisiae en la forma conjunta y secuencial, a diferentes pH, 6.5, 5.5 y 4.5 y tiempos de fermentación alcohólica. Los mejores resultados se obtuvieron con el uso secuencial de S. cerevisiae y P. stipitis: productividad de 0.30 g/L.h para 48 fermentación y concentración de etanol de 14.7 g/L con un rendimiento de 0.294 g etanol/g celulosa para 72 h de fermentación. RESUMO-A crescente demanda comercial de etanol alavancou estudos sobre produção de etanol de segunda geração, como forma de reduzir a dependência do petróleo e ampliar a matriz energética brasileira.Neste contexto, se insere o presente trabalho, que estuda a produção de etanol por fermentações alcoólicas de Saccharomyces cerevisiae e Pichia stipitis com de bagaço de cana tratado.A produção de etanol foi realizada por processo de sacarificação e fermentação simultânea em reator batelada com os complexos enzimáticos brutos e 25 % de bagaço de cana-de-açúcar tratado por explosão a vapor, utilizando as leveduras P. stipitis e S. cerevisiae na forma conjuntas e seqüencial, em diferentes pH, 6,5, 5,5 e 4,5 e tempos de fermentação alcoólica.Os melhores resultados foram obtidos com o uso sequencial de S. cerevisiae e P. stipitis: produtividade de 0,30 g/L.h para 48 de fermentação e concentração de etanol de 14,7 g/L com rendimento de 0,294 g etanol/g celulose para 72 h de fermentação. Summary - The growing commercial demand for ethanol has leveraged studies on the production of second-generation ethanol, as a way to reduce dependence on oil and expand the Brazilian energy matrix. In this context, the present work is inserted, which studies the production of ethanol by alcoholic fermentations of Saccharomyces cerevisiae and Pichia stipitis with treated sugarcane bagasse. Ethanol production was carried out by saccharification process and simultaneous fermentation in a batch reactor with the crude enzyme complexes and 25% of sugarcane bagasse treated by steam explosion, using the yeasts P. stipitis and S. cerevisiae in the joint and sequential form, at different pH, 6.5, 5.5 and 4.5 and alcoholic fermentation times. The best results were obtained with the sequential use of S. cerevisiae and P. stipitis: productivity of 0.30 g/L.h for 48 fermentation and ethanol concentration of 14.7 g/L with a yield of 0.294 g ethanol/g cellulose for 72 h of fermentation. ملخص - استفاد الطلب التجاري المتزايد على الإيثانول من الدراسات المتعلقة بإنتاج الجيل الثاني من الإيثانول، كوسيلة للحد من الاعتماد على النفط وتوسيع مصفوفة الطاقة البرازيلية. في هذا السياق، يتم إدراج العمل الحالي، الذي يدرس إنتاج الإيثانول عن طريق التخمر الكحولي لـ Saccharomyces cerevisiae و Pichia stipitis مع قصب السكر المعالج. تم إنتاج الإيثانول عن طريق عملية التسكير والتخمير المتزامن في مفاعل دفعي مع مركبات الإنزيم الخام و 25 ٪ من قصب السكر المعالج بالانفجار البخاري، باستخدام الخمائر P. stipitis و S. cerevisiae في الشكل المفصلي والمتسلسل، عند درجة الحموضة المختلفة، 6.5، 5.5 و 4.5 وأوقات التخمير الكحولي. تم الحصول على أفضل النتائج مع الاستخدام المتسلسل لـ S. cerevisia و P. stipitis: إنتاجية 0.30/L. 48 لتركيز الإيثانول في 14.7/L مع غلة من الإيثانول/0.294 مع الغلوز.

Abstract In order to effectively improve the economic benefits of large-scale fracturing of the single well in tight reservoirs, avoid investment risks and raise development effects, research on the forecast means of large-scale multi-branch fracturing capacity is carried out. Large-scale fracturing has high costs and high investment risks, it is necessary to conduct relatively accurate forecast for the capacity after fracturing to reduce investment risks. On the basis of the single-well capacity data of 78 large-scale fracturing wells that have been put into production in the Hailar Basin, the geological, development and engineering factors affecting capacity were deeply analyzed and summarized. According to different applicable conditions, the theoretical derivation and polynomial linear regression methods are used; two different capacity forecast models of tight reservoir are given. These two forecast models are used, the error of capacity forecast results after fracturing is less than 15%, and the accuracy can meet the actual application requirements of the mine, therefore, this forecast method provides a powerful technical support for the promotion of large-scale fracturing technology and reducing economic risks.

Addressing the environmental risks related to contamination of groundwater with the phenolics, benzene, toluene, ethyl benzene, xylene (BTEX) and polycyclic aromatic hydrocarbons (PAHs), which might be potentially released from the underground coal gasification (UCG) under adverse hydrogeological and/or operational conditions, is crucial in terms of wider implementation of the process. The aim of this study was to determine the main organic pollutants present in the process condensate generated during the UCG trial performed on hard coal seam in the Experimental Mine ‘Barbara’, Poland; 8,933 L of condensate was produced in 813 h of experiment duration (including 456 h of the post-process stage) with average phenolics, BTEX and PAH concentrations of 576,000, 42.3 and 1,400.5 μg/L, respectively. The Hierarchical Clustering Analysis was used to explore the differences and similarities between the samples. The sample collected during the first 48 h of the process duration was characterized by the lowest phenanthrene, anthracene, fluoranthene and pyrene contents, high xylene content and the highest concentrations of phenolics, benzene, toluene and ethyl benzene. The samples collected during the stable operation of the UCG process were characterized by higher concentrations of naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, while in the samples acquired in the post-process stage the lowest concentrations of benzene, toluene, naphthalene, acenaphthene and fluorene were observed.