Future Biomass Research Articles

Research on the development status of biomass energy serving the construction of ecological civilization: A case study in Henan province, China

The development and utilization of biomass energy based on the thermochemical conversion of crop biomass to produce hydrogen are of great significance for promoting China’s ecological civilization construction, energy revolution, and low-carbon economic development. Henan province is one of the largest agricultural and pasturage provinces in China. Based on the analysis of the status and trends of Henan’s biomass energy (BE) development, this paper summarizes the present status of the construction of ecological civilization (CEC) and the factors restricting its development. Challenges in developing biomass energy are analyzed systematically, and strategies and key technical directions for future biomass energy development are discussed. Finally, the paper presents countermeasures and suggestions for CEC based on the development of BE, which will vigorously promote the development and utilization of BE and the process of CEC. This research provides a reference for the further development of BE and CEC in the future.

Influence of seagrass meadows on nursery and fish provisioning ecosystem services delivered by Ria Formosa, a coastal lagoon in Portugal

This study is the first to evaluate the fish provisioning services of a whole transitional landscape (Ria Formosa lagoon, Portugal), in parallel with the enhancement of growth, survival and production of single cohorts of the most important commercial fish species by vegetated and unvegetated sub-tidal habitats. Based on monthly beach seine samples, total density and biomass of 96 species of fishes were 1.89 and 3.03 times greater in vegetated habitats than unvegetated habitats, respectively. Vegetated habitat enhanced survival in six of eight commercial species for which survival could be estimated in both habitats. The total production of all 12 commercially important species within vegetated habitat was approximately double that of unvegetated habitat, with production enhancement in 7 of 12 species ranging from 1.8 to 169-fold for the vegetated habitats. Within the lagoon, vegetated sub-tidal habitat covers an area 5-fold smaller than unvegetated habitat, yet it accounts for 27.1 % of fish production. Estimated total lifetime economic values of the single cohorts of the 12 commercial species were between 30 million and 59 million EUR. An exceptionally strong year class of the European seabass (Dicentrarchus labrax), a species with higher density and biomass in unvegetated habitat, accounts for the higher overall values per hectare for unvegetated habitat (Low natural mortality (M): EUR 32,844 ha−1; High M: EUR 16,751 ha−1) than for vegetated habitat (Low M: EUR 22,028 ha−1; High M: EUR 10,700 ha−1). These results highlight the enormous importance of temperate coastal lagoons as a nursery and source of recruits for coastal fisheries. Our evaluation of fish provisioning services based on data for individual cohorts of fish for a whole transitional landscape is a stronger and more valid approach for estimating future biomass and value than previous studies based on mean densities and biomasses of fish that did not distinguish between cohorts.

Semiempirical compensated optimal coherence amplitude method to invert forest height based on InSAR

Interferometric synthetic aperture radar (InSAR) is an important resource for rapidly obtaining forest height information. The coherence amplitude method relies solely on interferometric coherence amplitude information for forest height inversion; however, interferometric data are commonly affected by decorrelation factors including time, baseline, and noise decorrelation, as well as observation geometry errors, leading to errors in estimated forest height. Thus, in this paper, we propose a method to improve the accuracy of forest height estimation by correcting the decorrelation and vertical wave number using a priori forest height knowledge. UAVSAR-L cross-polarization channel HV data from the AfriSAR project are used as interferometric data to invert the forest height using the coherence amplitude method, and the relative height variable RH100 from land, vegetation, and ice sensor light detection and ranging (LiDAR) is used for validation. We optimize the coherence amplitude method by iteratively setting different steps for the nonvolume decorrelation (γd) and the correction parameter (τ) for the vertical wavenumber (kz). The optimal compensation parameter is identified when the root mean square error (RMSE) between the inversion height and LiDAR height is minimized, and the stability of the returned parameter is evaluated through an independent validation sample. Our results indicate that enhancing the coherence amplitude method using a semiempirical iterative approach can effectively improve inversion accuracy. In the validation results, all compensation schemes exhibit a significant improvement in the inversion results compared with those without parameter compensation. The R2 increases by 0.13 and the RMSE decreases by 9.88 m when compensating only γd, whereas the R2 value does not change when only compensating kz, but the RMSE decreases by 19.24 m. When compensating for both γd and kz, the R2 increases by 0.08, and the RMSE decreases by 19.73 m. This changing pattern is consistent with that recorded in the training sample, indicating that our proposed parameter compensation scheme for the coherence amplitude method is effective. With the widespread usage of satellite data, such as ALOS-2 and SAOCOM, as well as the future TanDEM-L and BIOMASS satellites and NISAR program, the combination of ICESat-2 and GEDI forest height data to compensate and optimize inversion results and model parameters is expected to greatly improve the efficiency of forest resource monitoring in the future.

Temperature impacts on fish physiology and resource abundance lead to faster growth but smaller fish sizes and yields under warming.

Resolving the combined effect of climate warming and exploitation in a food web context is key for predicting future biomass production, size-structure and potential yields of marine fishes. Previous studies based on mechanistic size-based food web models have found that bottom-up processes are important drivers of size-structure and fisheries yield in changing climates. However, we know less about the joint effects of 'bottom-up' and physiological effects of temperature; how do temperature effects propagate from individual-level physiology through food webs and alter the size-structure of exploited species in a community? Here, we assess how a species-resolved size-based food web is affected by warming through both these pathways and by exploitation. We parameterize a dynamic size spectrum food web model inspired by the offshore Baltic Sea food web, and investigate how individual growth rates, size-structure, and relative abundances of species and yields are affected by warming. The magnitude of warming is based on projections by the regional coupled model system RCA4-NEMO and the RCP 8.5 emission scenario, and we evaluate different scenarios of temperature dependence on fish physiology and resource productivity. When accounting for temperature-effects on physiology in addition to on basal productivity, projected size-at-age in 2050 increases on average for all fish species, mainly for young fish, compared to scenarios without warming. In contrast, size-at-age decreases when temperature affects resource dynamics only, and the decline is largest for young fish. Faster growth rates due to warming, however, do not always translate to larger yields, as lower resource carrying capacities with increasing temperature tend to result in decline in the abundance of larger fish and hence spawning stock biomass. These results suggest that to understand how global warming affects the size structure of fish communities, both direct metabolic effects and indirect effects of temperature via basal resources must be accounted for.

On the role of forests and the forest sector for climate change mitigation in Sweden

AbstractWe analyse the short‐ and long‐term consequences for atmospheric greenhouse gas (GHG) concentrations of forest management strategies and forest product uses in Sweden by comparing the modelled consequences of forest resource use vs. increased conservation at different levels of GHG savings from carbon sequestration and product substitution with bioenergy and other forest products. Increased forest set‐asides for conservation resulted in larger GHG reductions only in the short term and only when substitution effects were low. In all other cases, forest use was more beneficial. In all scenarios, annual carbon dioxide (CO2) sequestration rates declined in conservation forests as they mature, eventually approaching a steady state. Forest set‐asides are thus associated with increasing opportunity costs corresponding to foregone wood production and associated mitigation losses. Substitution and sequestration rates under all other forest management strategies rise, providing support for sustained harvest and cumulative mitigation gains. The impact of increased fertilization was everywhere beneficial to the climate and surpassed the mitigation potential of the other scenarios. Climate change can have large—positive or negative—influence on outcomes. Despite uncertainties, the results indicate potentially large benefits from forest use for wood production. These benefits, however, are not clearly linked with forestry in UNFCCC reporting, and the European Union's Land Use, Land‐Use Change and Forestry carbon accounting, framework may even prevent their full realization. These reporting and accounting frameworks may further have the consequence of encouraging land set‐asides and reduced forest use at the expense of future biomass production. Further, carbon leakage and resulting biodiversity impacts due to increased use of more GHG‐intensive products, including imported products associated with deforestation and land degradation, are inadequately assessed. Considerable opportunity to better mobilize the climate change mitigation potential of Swedish forests therefore remains.

Результаты гидроакустических исследований байкальского омуля (Coregonus migratorius) на рыбопромысловых акваториях озера Байкал с использованием отечественных информационных разработок

After many years of interruptions, sonar surveys of the main fishing areas of Lake Baikal were carried out: Selenginsky shallow water and Northern Baikal. When performing hydroacoustic research and data processing, a Simrad EY500 scientific echo sounder with a frequency of 70 kHz and with an ES 70-11 antenna (split beam), a domestic GIS "CartMaster" with a hydroacoustic database was used. In the area of the Selenginsky shallow water, accumulations of omul were recorded in the depth range from 70 to 300 meters. In the water area of 145,010 hectares, the number of omul was 11386970, and its biomass was 4108 tons. The maximum registrations of omul accumulations per unit of distance traveled on Northern Baikal were higher compared to the Selenga shallow water. The densest accumulations of omul were recorded in the depth range from 120 to 250 meters. In the water area of 14695 hectares, the number of omul was 6370,540, and its biomass was 992 tons.
 The results of hydroacoustic surveys turned out to be comparable with the results of biological studies and on the basis of which it can be assumed that the decline in abundance and biomass has stopped. There is an increase in spawning herds and the number of larvae, which means that we can expect an increase in the total biomass in the foreseeable future.

Modelling how bottom-up and top-down processes control the major functional groups of biota in a large temperate shallow lake

ABSTRACT Ecosystem models that measure the impact of quantitative interactions between trophic levels are widely used tools in ecosystem studies and fishery management. We constructed a mass-balance trophic model using an Ecopath with Ecosim (EwE) modelling suite for large shallow Lake Võrtsjärv, Estonia. The model was calibrated for 36 years (1983–2018) and included 23 functional groups. We examined trophic relationships, functional group interactions, energy fluxes, and keystone groups having a high impact on the ecosystem relative to their biomass. We tested 6 hypothetical scenarios based on future biomass changes for the major functional groups (phytoplankton, zooplankton, macrozoobenthos, piscivorous fish, and bream) for 20 years. The output of the predictive scenarios showed that the biomass changes of planktonic groups would affect the whole food web. Among consumers, macrozoobenthos was crucial for the food web balance because a reduction of their biomass would also reduce the biomass of the fish community. Changes in fish catches would cause minimal biomass difference in other groups. While increased fishing pressure on large piscivores would have a marked effect on the rest of the food web, the reduction of nonpiscivorous fish like bream would have little effect. The results suggested a positive relationship between the biomass of small phytoplankton and fish, alluding to the prevalence of bottom-up trophic processes. These outcomes could be helpful for assessing trophic dynamics in shallow lakes and important aspects for fisheries and ecosystem management.

Türkiye’de Pamuk Saplarının Biyogaz ve Sentez Gazı Potansiyelinin Değerlendirilmesi

Turkey, being one of the largest producers of world cotton production, utilizes biomass through direct incineration for electricity generation which accounts for 1.5% of the total electricity generation in Turkey. In this work, biogas potential of cotton stalks was assessed to present a foresight to the future biomass valorizations in the country. Cotton stalks harvested in six cities located in the Southeastern, Aegean and Çukurova regions of Turkey were evaluated and discussed with respect to their potential in electricity generation and the invoiced electricity consumption in 2019. These cities were found to yield 15.6 million tonnes of cotton stalks with an annual 3.1 billion m3 of methane and also, 12 TWh of electricity generation that could meet almost 32% of the electricity demand. For Southeastern region, region’s electricity consumption could be met by 99.5% with the anaerobic digestion of cotton stalks (9 million tonnes/yr). Methane potentials of cotton stalks were compared with the corresponding syngas yields and lower percentages were obtained for syngas. Anaerobic digestion and thermochemical conversion of agricultural residues, being proposed as energy strategies in this study, could help to accelerate the activities on bioenergy share in Turkey.

The Crucial Role of Bioenergy in a Climate‐Neutral Energy System in Germany

AbstractGreenhous gas mitigation requires urgent action, especially in transforming the energy system. Bioenergy is expected to counterbalance the variable power from wind and solar energy, but also for the de‐fossilization of the heat and transport sectors. This study assesses the wide range of options and evaluates the most cost‐efficient allocation of biomass for 95 % greenhouse gas emission reduction in the German energy system till 2050. The final state in 2050 shows bioenergy in different sectors, including pellet and woodchip boilers, bio‐based methane, different combined heat and power concepts, as well as liquid fuels, such as synthetic kerosene. Lignocellulosic biomass makes up the major proportion of future biomass options; however, appropriate strategies are needed to mobilize it.

A Review of the Sustainable Utilization of Rice Residues for Bioenergy Conversion Using Different Valorization Techniques, Their Challenges, and Techno-Economic Assessment

The impetus to predicting future biomass consumption focuses on sustainable energy, which concerns the non-renewable nature of fossil fuels and the environmental challenges associated with fossil fuel burning. However, the production of rice residue in the form of rice husk (RH) and rice straw (RS) has brought an array of benefits, including its utilization as biofuel to augment or replace fossil fuel. Rice residue characterization, valorization, and techno-economic analysis require a comprehensive review to maximize its inherent energy conversion potential. Therefore, the focus of this review is on the assessment of rice residue characterization, valorization approaches, pre-treatment limitations, and techno–economic analyses that yield a better biofuel to adapt to current and future energy demand. The pre-treatment methods are also discussed through torrefaction, briquetting, pelletization and hydrothermal carbonization. The review also covers the limitations of rice residue utilization, as well as the phase structure of thermochemical and biochemical processes. The paper concludes that rice residue is a preferable sustainable biomass option for both economic and environmental growth.

Polarimetric radar interferometry in the presence of differential Faraday rotation

Faraday rotation (FR) affects the low-frequency transionospheric radar by creating cross-talk between polarizations. The baseline part of FR can be compensated for by applying an appropriate linear transformation—rotation with a known FR angle. Yet the differential Faraday rotation (dFR), which is a frequency-dependent part of FR, persists and introduces distortions into the observations. We build a simplified model with two polarimetric scattering channels that allows us to evaluate the effect of dFR on the accuracy of PolInSAR reconstruction. We also assess the severity of distortions due to dFR for the future BIOMASS mission and several other spaceborne radar systems.

Allometric Equation for Aboveground Biomass Estimation of Mixed Mature Mangrove Forest

The disturbance of mangrove forests could affect climate regulation, hydrological cycles, biodiversity, and many other unique ecological functions and services. Proper biomass estimation and carbon storage potential are needed to improve forest reference on biomass accumulation. The establishment of a site-specific allometric equation is crucial to avert destructive sampling in future biomass estimation. This study aimed to develop a site-specific allometric equation for biomass estimation of a mix-mature mangrove forest at Sungai Pulai Forest Reserve, Johor. A stratified line transect was set up and a total of 1000 standing trees encompassing seven mangrove tree species were inventoried. Destructive sampling was conducted using the selective random sampling method on 15 standing trees. Five allometric equations were derived by using diameter at breast height (D), stem height (H), and wood density (ρ) which were then compared to the common equation. Simulations of each allometric equation regarding species were performed on 1000 standing trees. Results showed that the single variable (D) equation provided an accurate estimation, which was slightly improved when incorporated with the H variable. Both D and H variables, however, gave inconsistent results for large-scale data and imbalance of sampled species. Meanwhile, the best fit either for small-scale or large-scale data, as well as for imbalanced sample species was achieved following the inclusion of the ρ variable when developing the equation. Hence, excluding the H variable while including the ρ variable should be considered as an important determinant in mixed mangrove species and uneven-aged stand for aboveground biomass estimation. This valuation can both improve and influence decision-making in forest development and conservation.

Perceptions of long-term impact and change following a midwife-led biomass smoke education program for mothers in rural Uganda: a qualitative study.

Women and children in Uganda and other low- and middle-income countries are exposed to disproportionately high levels of household air pollution from biomass smoke generated by smoke-producing cookstoves, especially in rural areas. This population is therefore particularly vulnerable to the negative health effects caused by household air pollution, including negative pregnancy outcomes and other health issues throughout life. The Midwife Project, a collaboration between research and health teams in the UK and Uganda, began in 2016 to implement an education program on lung health for mothers in Uganda, to reduce the health risks to women and children. Education materials were produced to guide midwives in the delivery of health messages across four rural health centres, and mixed-methods results of knowledge questionnaires and interviews demonstrated knowledge acquisition, acceptability and feasibility. This qualitative follow-up study aimed to improve understanding of the longer term impact of this education program from the perspective of midwives, village health team members and mothers, in consideration of rolling the program out more widely in rural Uganda. Purposive sampling was carried out to recruit consenting antenatal or postnatal women, midwives and village health team members who had been involved in an education session. Individual interviews were conducted with 12 mothers and four village health team members, and four focus groups were conducted with 10 midwives in total. Interviews and focus groups were conducted across all four health centres by two researchers and six translators as appropriate depending on language spoken (English or Lusoga). These were semi-structured and directed by topic guides. Reflective and observational notes were also made. A thematic analysis was carried out by two researchers, along with production of a narrative for each mother, to enrich understanding of each individual story. Midwives and village health teams had continued with the program well past the project end date and all mothers expressed making, or intending to make, changes, suggesting long-term feasibility and acceptability. Main themes generated were ability to change and changes made, ability to change dictated by money, importance of practical education, perceived health improvements, and passing on knowledge. Additional findings were that some education topics seemed to be overlooked, and there was a lack of clarity about the village health team role for the purposes of this program. Some mothers had been motivated to overcome financial barriers, for example by reconstructing cooking areas cheaply themselves. However, information given in the program about building advice and potential financial gains was inconsistent. Recommendations for future biomass smoke education should include explicit building advice, emphasis on financial gains, encouragement to share the knowledge acquired and clarification of the village health team role. These program changes will improve focus and relevancy, optimise impact and, with behaviour change and implementation strategy in mind, could be used for widespread rollout in rural Uganda. Future research should include quantitative data collection to objectively examine surprising perceived health benefits, including reduction in malaria and burns, and further qualitative work on why some education content appears neglected.

Bio‐derived sodium silicate for the manufacture of alkali‐activated binders: Use of bamboo leaf ash as silicate source

AbstractAlkali activated binders are a promising alternative to the use of Portland cement in the manufacture of concrete for curbing CO2 emissions. Novel sources of silicates have been investigated in recent years for reducing cost and environmental impacts associated with the use of chemical activators. This study describes the production of solid sodium silicate (SS) activating powder from bamboo leaf ash (BLA). Bamboo leaves were calcined at 550–800°C, mixed with NaOH pellets, and heated in an oven at 300°C. The obtained silicate powder was used for activating blended fly ash/slag samples. Mechanical and microstructural properties of BLA‐based samples were compared to those of samples made with commercially available chemicals. The strength of BLA‐activated mortars matched the commercially‐sourced activators, being 25–30 MPa at 7 days and exceeding 40 MPa at 28 days. The microstructural analysis suggested that BLA‐based SS showed a lesser degree of dissolution of precursors at 7 days, but the quality of the matrix was higher than that of NaOH‐activated samples. These results confirmed that the reactivity of BLA‐silicate powder was similar to that of commercial SS solutions, and show the potential valorization of future biomass renewable waste in the production of low carbon, alkali‐activated concretes.

Using Machine Learning to Identify the Potential Marginal Land Suitable for Giant Silvergrass (Miscanthus × giganteus)

Developing biomass energy, seen as the most important renewable energy, is becoming a prospective solution in attempting to deal with the world’s sustainability-related challenges, such as climate change, energy crisis, and carbon emission reduction. As one of the most promising second-generation energy crops, giant silvergrass (Miscanthus × giganteus) is highly valued for its high potential for biomass production and low maintenance requirements. Mapping the potential global distribution of marginal land suitable for giant silvergrass is an essential prerequisite for the development of giant silvergrass-based biomass energy. In this study, a boosting regression tree was used to identify the marginal land resources for giant silvergrass cultivation using influencing factors, which include climate conditions, soil conditions, topography conditions, and land use. The results indicate that there are 3068.25 million hectares of land resources worldwide suitable for giant silvergrass cultivation, which are mainly located in Africa (902.05 million hectares), Asia (620.32 million hectares), South America (547.60 million hectares), and North America (529.26 million hectares). Among them, countries with the most land resources, Russia and Brazil, have the first- and second-highest amounts of suitable marginal land for giant silvergrass, with areas of 373.35 and 332.37 million hectares, respectively. Our results also rank the involved factors by their contribution. Climatic conditions have the greatest influence on the spatial distribution of giant silvergrass, with an average contribution of 74.38%, followed by land use, with a contribution of 17.38%. The contribution of the soil conditions is 7.26%. The results of this study provide instructive support for future biomass energy policy development.

Tropical Forest Vertical Structure Characterization: From GEDI to P-Band SAR Tomography

Estimating tropical forests vertical structure using remote sensing is a challenge. Active sensors such as low-frequency Synthetic Aperture Radar (SAR) operating at P-band, with a wavelength of ~ 69 cm wavelength, and Light Detection and Ranging (LiDAR) are able to penetrate thick vegetation layers. While NASA’s Global Ecosystem Dynamics Investigation (GEDI) is collecting spaceborne liDAR data, the ESA’s next Earth Explorer BIOMASS mission will acquire multiple acquisitions over the same areas to form three-dimensional images through SAR tomography (TomoSAR) technique. Our study shows the potential value of GEDI and TomoSAR acquisitions in producing accurate estimates of forests vertical structure. By analyzing airborne P-band TomoSAR, airborne LiDAR, and spaceborne GEDI LiDAR at a tropical forest site in Paracou, French Guiana, South America, we show that both GEDI and P-band TomoSAR can directly measure surface, vegetation heights, and vertical profiles with high resolution and precision. Airborne TomoSAR is of higher quality than GEDI due to better penetration properties and precision. However, the GEDI vegetation height root-mean-square error is less than 5 m, for an average forest height value around 30 m at the Paracou site, which is similar to the expected performance of the future spaceborne BIOMASS mission. These results suggest GEDI measurements, i.e. shots with sensitivity greater than 98%, will provide a good reference of forest structure to calibrate the BIOMASS mission algorithms.

Functionalization of 0-D and 2-D carbon nitride nanostructures on bio-derived carbon spheres for sustainable electrochemical supercapacitors

• Carbon spheres derived from the Orange Juice through Hydrothermal process. • Functionalization of Carbon spheres with Carbon Nitride structures by one-pot process. • Fabrication of Eco-Friendly Supercapacitor Devices for Sustainability. • ASCs boasts a 1800% increase in PD with a mere 50% decrease in ED. A new carbon nitride nanoparticles-carbon microsphere composite is developed through a green and facile one-step hydrothermal synthesis process with orange juice (Citrus Sinensis) as the carbon source. The orange juice acts simultaneously as a reducing agent for converting melamine into carbon nitride nanostructures to in-situ modify the carbon microsphere surfaces for carbon nitride/carbon sphere heterostructure. The composite material synthesized then is used as an electrochemical electrode in asymmetric supercapacitor devices for charge storage applications. The electrochemical properties of the composite exhibits superior specific capacitance of 350 Fg −1 at 0.5 Ag −1 current density with ∼ 80% capacitance retention at 5 Ag −1 over 2000 charge–discharge cycles. The asymmetric device boasts a 1800% increase in the power density with a mere 50% decrease in the energy density, indicating an exceptional energy-power performance. The superior electrochemical properties of the device are attributed to high active surface sites of the composite with excellent accessibility, conductivity, and chemical interface for favorable charge transport. This novel work should open up the development of green and low-cost charge storage devices from natural biomass for sustainable future.

Cellulose Degrading Ability of Bacterial Strains Isolated from Gut of Termites in Vinhlong Province - Vietnam

Cellulose are the most abundant renewable biomass. The bioconversion of cellulose plays an important role for sustainable development and application in alcohol production, compost production and waste treatment. Termites were known as the most successful wood-degrading species on the earth, can degrade in large quantities of cellulosic biomass by activities of enzymes secreted by the termites and/or their gut. A total of 70 bacterial isolates were isolated from the gut of termites obtained from thirteen termite nests in TraOn district, VinhLong province, Mekong Delta, Vietnam. Of the 70 bacterial isolates, 60 (86%) are able to degrade CMC (Carboxyl Methyl Cellulose) after culturing in media containing CMC agar and halo formation after staining with Congo red. Among of them, 5 isolates having high CMC degradation efficiency are chosen to evaluate the potential ability to liberate glucose from cellulose of straw for 5, 10, 15 and 20 days respectively at room temperatures. The results showed that all of the 5 isolates have the cellulose degradation ability and produce the highest glucose contents after 15 days. Out of the 5 isolates, 2 produced glucose in large quantities are 2T1 isolate (0.73 g/L) and 5T6 isolate (0.79 g/L) in hydrolysis solutions. The 2T1, 5T6 strains were 98.99%, 99.01% of identity Paenibacillus humicus strain T20C, Psychrobacter faecalis strain AP3Ka respectively by 16S rRNA genes sequencing and could be potential sources of enzymes for cellulose hydrolysis from cellulosic biomass in future.

Predictive Monitoring of Shake Flask Cultures with Online Estimated Growth Models.

Simplicity renders shake flasks ideal for strain selection and substrate optimization in biotechnology. Uncertainty during initial experiments may, however, cause adverse growth conditions and mislead conclusions. Using growth models for online predictions of future biomass (BM) and the arrival of critical events like low dissolved oxygen (DO) levels or when to harvest is hence important to optimize protocols. Established knowledge that unfavorable metabolites of growing microorganisms interfere with the substrate suggests that growth dynamics and, as a consequence, the growth model parameters may vary in the course of an experiment. Predictive monitoring of shake flask cultures will therefore benefit from estimating growth model parameters in an online and adaptive manner. This paper evaluates a newly developed particle filter (PF) which is specifically tailored to the requirements of biotechnological shake flask experiments. By combining stationary accuracy with fast adaptation to change the proposed PF estimates time-varying growth model parameters from iteratively measured BM and DO sensor signals in an optimal manner. Such proposition of inferring time varying parameters of Gompertz and Logistic growth models is to our best knowledge novel and here for the first time assessed for predictive monitoring of Escherichia coli (E. coli) shake flask experiments. Assessments that mimic real-time predictions of BM and DO levels under previously untested growth conditions demonstrate the efficacy of the approach. After allowing for an initialization phase where the PF learns appropriate model parameters, we obtain accurate predictions of future BM and DO levels and important temporal characteristics like when to harvest. Statically parameterized growth models that represent the dynamics of a specific setting will in general provide poor characterizations of the dynamics when we change strain or substrate. The proposed approach is thus an important innovation for scientists working on strain characterization and substrate optimization as providing accurate forecasts will improve reproducibility and efficiency in early-stage bioprocess development.

Challenges and Perspective of Recent Biomass Pretreatment Solvents

The increased demands on renewable and sustainable products require enhancing the current conversion efficiency and expanding the utilization of biomass from a single component (i.e., cellulose) to entire biomass components in the biorefinery concept. Pretreatment solvent plays a critical role in various biorefinery processes. Recent pretreatment solvents such as organic co-solvents, acid hydrotropes, ionic liquids and deep eutectic solvents showed effective biomass fractionation as well as preservation of high-quality cellulose and lignin under mild conditions. Despite these significant enhancements in biomass pretreatment solvent, there are still many challenges, such as feedstock variety, valorization of non-cellulose components, and eco-friendliness of the applied catalyst and solvent. These technical, economic and environmental obstacles should be considered in future biomass pretreatment solvents. In particular, the development of feedstock-agnostic solvent with high fractionation performance for high quality and quantity of all three major components (i.e., cellulose, hemicellulose, and lignin) together would be an ideal direction.