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Residents living adjacent to forests commonly gather non-timber forest products (NTFPs) for income, nourishment, ailment treatment, firewood, religious reasons, and artefacts. This study focused on the locals’ perception of NTFP value addition in forest-adjacent communities in Ghana. To determine which NTFPs are collected, we interviewed 732 residents about their perception of value addition to the NTFPs collected and if value addition has impacted the commercialisation and quality of the products obtained from the forest. We found that 97.5% of those surveyed frequently visited the forest to gather different NTFPs. For example, mushrooms, snails, honey and others were the most collected. Also, most interviewees do not process or add value to the NTFPs collected from the forest; thus, adding value to these NTFPs could increase incomes in the future. Future research should focus on educating locals about the value addition to NTFPs, and processes for increasing the price of NTFPs by adding value and commercialising these products. Proper commercialising of NTFPs will help improve the lives of the locals.

The pulp and paper industry produces a diverse range of side-streams from multi-stage processes, but these remain underutilized despite their high potential for use as biofuels. This study investigated acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum DSM 1731 from the side-streams of three different stages of the pulp and paper manufacturing process (PI, PII, and PIII). Biomass specimens with and without water washing were pretreated with 0.2% H2SO4 at 180 °C for 10 min, followed by enzymatic hydrolysis, to obtain fermentable sugars. The results showed that the produced ABE solvent concentrations were 12.8 g/L, 5.2 g/L, and 6.3 g/L from PI, PII, and PIII, respectively. The butanol yields of PI, PII, and PIII were 0.25, 0.18, and 0.19 g/g sugars, respectively. Among the tested side-streams, PI was shown to have potential as a feedstock for butanol production without prewashing prior to dilute acid pretreatment, enzymatic hydrolysis, and microbial fermentation.

Soil and water contaminations are caused by rare earth elements (REEs) due to mining and industrial activities, that threaten the ecosystem and human health. Therefore, phytoremediation methods need to be developed to overcome this problem. To date, little research has been conducted concerning the phytoremediation potential of Salix for REEs. In this study, two Salix species (Salix myrsinifolia and Salix schwerinii) and two Salix cultivars (Klara and Karin) were hydroponically exposed to different concentrations of six-REE for 4 weeks. The treatments were: T1 (Control: tap water), T2 (La: 50 mg/L) and T3 (La 11.50 + Y 11 + Nd 10.50 + Dy 10 + Ce 12 and Tb 11.50 in mg L

European Union bioeconomy policy emphasizes that the production of renewable transportation fuels should replace fossil fuels as much as possible. In particular, the utilization of waste or side-stream lignocellulosic materials for fuel production is highly recommended. Moreover, future crises forcing a reliance on locally available sources for fuels and energy may become increasingly common. Barley straw, a common agricultural residue in northern Europe, is a potential raw material for bioalcohol production via fermentation. In this study, the technoeconomic and environmental sustainability of bioethanol and biobutanol production from barley straw were evaluated. When compared with fossil gasoline production and use, the greenhouse gas emissions reduction 77.6% and 72.1% were achieved for ethanol and butanol production, respectively. Thus, the emission reduction of 65% for biofuels demanded by the European Union renewable energy directive was achieved in both biofuel production processes evaluated. However, our results indicated that ethanol production from barley straw, a well-known and mature technology, was an economically feasible process (NPV positive, IRR 20%) but that butanol production with Clostridium species through acetone-butanol-ethanol fermentation has still technoeconomic challenges to overcome (NPV negative, IRR below 10%). This was mainly due to the low yield and high recovery costs of butanol.

Background. Sahara is one of the largest deserts in the world. The hard conditions especially high temperature and aridity lead to unique adaptation of organisms that could be a potential source of new metabolites. In this respect, two Saharan soils from El Oued Souf and Beni Abbes in Algeria were collected. The bacterial isolates were selected by screening the antibacterial, antifungal, and enzymatic activities. The whole genomes of the two native Saharan strains were sequenced to study the desert Streptomyces microbiology and ecology from genomic perspective. Results. The strains Babs14 (from Beni Abbes, Algeria) and Osf17 (from El Oued Souf, Algeria) were initially identified by 16S rRNA sequence as belonging to the Streptomyces genus. The whole genome sequencing of the two strains was performed by using Pacific Biosciences Sequel II technology (PacBio) and it showed that Babs14 and Osf17 have a linear chromosome of 8.00 Mb and 7.97 Mb, respectively. The number of identified proteins is 6910 in Babs14 and 6894 in Osf17. No plasmids were found in Babs14, whereas three plasmids were detected in Osf17 and no genome duplications were detected in the two strains. Although the strains have different phenotypes and are from different regions, they are slightly different from each other in protein sequence level but, differ more from their earlier published relatives. 29 biosynthetic gene clusters (BGCs) coding for secondary metabolites were predicted in each strain indicating antifungal, antibiotic, and other activities of Babs14 and Osf17. Moreover, many other BGCs were related to biosynthesis of factors needed in response to environmental stress in temperature, UV light and osmolarity. Conclusion. The genome sequencing of Saharan Streptomyces strains revealed factors that are related to their adaptation to an extreme environment and stress conditions. The genome information gives tools to study the ecological adaptation in desert environment and to explore the bioactive compounds of these microorganisms. The two whole genome sequences are among the first ones for the Streptomyces genus of Algerian Sahara. The present research was undertaken as a first step to explore more profoundly the desert microbiome.

This study assesses the wood waste generation, its management practices, and its effects on the forests in Ghana. The rate of logging in Ghana has increased and this can be attributed to the increase in the establishment of Sawmilling companies in the country. Increased in the installation of sawmilling companies has increased the sawn timber production. The use of outmoded milling machines has led to an increase in waste generation. An increase in production has led to an increase in the annual allowable cut in the country, which has overrun the limit of sustainable forestry. A qualitative research method was employed for the research work. A well-structured questionnaire was administered to the study to solicit the views of the wood industries about wood waste generation and its management practices. The study population comprised of 50 sawmilling companies. From the data collected, it was observed that most of the timber production companies do not know how to manage the waste generated and the waste is left un-utilized. In general 80% of the timber production companies responded that they have an idea of wood waste management but do not have the technical know-how to manage the waste. It was observed that 80% of the timber production companies do not manage the waste they generate during their operations. Wood shavings, sawdust, wood slabs, offcuts, branches, and others are left un-utilized. From the observations made in the visited sawmills, chunks of waste are generated on the site. The fact that the wood which is un-utilized (waste) and the wood, which is utilized as sold products, are equal in cost to the company which highlights the poor material and cost-efficiency. Wood industry materials and cost efficiency, together with waste management practices and their contribution to deforestation in the country, are discussed.

The dilute acid-catalyzed extraction of hemicellulosic monosaccharides from the short-rotation coppice Salix schwerinii E. Wolf was optimized to find a balance between the yields of fermentable monosaccharides and sugar degradation products for non-detoxified acetone-butanol-ethanol fermentation with Clostridium acetobutylicum. At the same time, the cellulosic and lignin fractions were kept as intact as possible for further refining. The highest xylose and glucose yields in the liquid prehydrolysate were 65% and 9.45% of their respective original content at a combined severity of 2.29. Increased concentrations of glucose and sugar degradation products in the liquid prehydrolysates were detected with an increasing pretreatment temperature and combined severity, while the acid-insoluble lignin remained stable. During the fermentation of the non-detoxified liquid prehydrolysate with grain starch as the supplement, 66% of the xylose was utilized, and the butanol and acetone-butanol-ethanol yields were 0.22 g/g and 0.35 g/g monosaccharides, respectively, in the fermentation medium. The results suggested that the hemicellulose in S. schwerinii can be separately extracted as a side stream and utilized for butanol fermentation with starch-based materials without a separate detoxification stage.

New energy crops adapted to northern conditions of Europe can broaden the portfolio of agricultural based biofuel options in an area with currently few alternatives. This study evaluates two energy crops, giant knotweed (Fallopia sachalinensis var. ‘Igniscum’) and Virginia mallow (Sida hermaphrodita), as possible biomass feedstocks for biofuels in southern Finland. The collected data includes yield productivity, physical and chemical properties, and energy content. The dry matter yield of giant knotweed ranges from 5.41 odt·ha−1 to 27.67 odt·ha−1, whereas Virginia mallow ranges from 6.72 odt·ha−1 to 16.72 odt·ha−1. Pellets from both crops meet the requirements regarding standards. Giant knotweed presents a bulk density of 677.71 kg·m−3 and Virginia mallow 725.18 kg·m−3. The results of mechanical durability of giant knotweed do not exceed the minimum threshold of the standards, with 96.73 w-%, while Virginia mallow is 92.86 w-%. The analysis of the ash content results in 1.5% for giant knotweed and 2.19% for Virginia mallow. The quantities of chlorine (Cl) and sulphur (S) are below the recommended thresholds. Finally, the energy content with moisture content of 5 w-% of giant knotweed and Virginia mallow were 19.97 MJ·kg−1 and 19.68 MJ·kg−1, respectively. Both crops prove are valid alternatives in the climatic and soil conditions of Northern Europe.

This study assessed the energy and environmental impacts in terms of second-generation (2G) bioethanol production, renewable electricity generation and greenhouse gas (GHG) emissions reduction potential of surplus rice straw (SRS) in India. National rice production database, and standard procedures for life cycle assessment of rice straw to 2G bioethanol production using two different pretreatment technologies namely, dilute acid (DA) and steam explosion (SE) pretreatments were explored for the analysis. Two scenarios (benchmark and resource-efficient) were constructed to evaluate the availability of SRS and to determine the potential from 2020 to 21 to 2030–31. Under benchmark for the year 2030–31, the potential from SRS using DA and SE pretreatment methods for the production of 2G bioethanol and the surplus renewable electricity generation were estimated to be 10,547 and 11,165 million L; and 5295 and 6928 GWh, respectively, and the corresponding GHG emissions reduction potential were assessed to be 11,954 and 14,375 kt CO2eq., respectively while generated renewable electricity replaces crude oil-driven grid electricity, and 11,498 and 14,498 kt CO2eq., respectively while generated renewable electricity replaces coal-driven grid electricity. The study revealed that both the availability of SRS and the choice of pretreatment method play decisive roles in the determination of its potential.

Neutralization is essential to maintain the pH for enzymatic hydrolysis of cellulose followed by fermentation of biofuels. This study investigated the effect of salts formed during the neutralization on the enzymatic hydrolysis of cellulosic materials and acetone–butanol–ethanol (ABE) fermentation. The results showed that the formed Ca-citrate salt considerably decreased the glucose release by 26.9% and 26.1% from Avicel and sulfuric acid-pretreated hybrid Pennisetum, respectively, which was probably due to the unproductive adsorption of cellulases by Ca-citrate solids. On the other hand, the formed soluble Na and Ca salts severely inhibited ABE fermentation, thereby decreasing the ABE concentration from 12.8 g L−1 to 0–10.7 g L−1 in different degrees, but no or slight inhibition was observed when the Ca salts formed as precipitates. In particular, Ca-sulfate did not show apparent inhibition of both hydrolysis and fermentation. Therefore, the selection of suitable pretreatment and neutralizing reagents is an alternative way to avoid process inhibition in biofuel production from lignocellulosic materials.

In many Baltic regions, short-rotation willow (Salix spp.) is used as a vegetation filter for wastewater treatment and recycling of valuable nutrients to upsurge bioeconomy development. In this context, a four-year field trial (2016–2019) was carried out near a wastewater treatment plant in eastern Finland (Outokumpu) to investigate the effect of the processed wastewater (WW) on biomass production as well as the nutrients uptake capability (mainly N and P) by a willow variety (Salix schwerinii). Results indicated that WW irrigation expressively increased the willow diameter growth and biomass yield around 256% and 6510%, respectively, compared to the control treatment site (without WW). The willow was also able to accumulate approximately 41–60% of the N and 32–50% of the P in two years (2018–2019). Overall, willow showed a total 20% mortality rate under WW irrigation throughout the growing periods (2017–2019) as compared to control (39%). The results demonstrate that willow has the potential to control eutrophication (reducing nutrients load) from the wastewater with the best survival rate and can provide high biomass production for bioenergy generations in cold climatic conditions.

This paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination of the assessment measures. Geochemical and ecotoxicological classifications are presented that may prove useful for sediment evaluation. Among the geochemical indices, several individual pollution indices (CF, Igeo, EF, Pi (SPI), PTT), complex pollution indices (PLI, Cdeg, mCdeg, Pisum, PIAvg, PIaAvg, PIN, PIProd, PIapProd, PIvectorM, PINemerow, IntPI, MPI), and geochemical classifications are compared. The ecotoxicological assessment includes an overview of Sediment Quality Guidelines (SQG) and classifications introduced nationally (as LAWA or modified LAWA). The ecotoxicological indices presented in this review cover individual (ERi) and complex indices (CSI, SPI, RAC, PERI, MERMQ). Biomonitoring of contaminated sites based on plant bioindicators is extensively explored as an indirect method for evaluating pollution sites. The most commonly used indices in the reviewed papers were Igeo, EF, and CF. Many authors referred to ecotoxicological assessment via SQG. Moreover, PERI, which includes the toxic response index, was just as popular. The most recognised bioindicators include the Phragmites and Salix species. Phragmites can be considered for Fe, Cu, Cd, and Ni bioindication in sites, while Salix hybrid cultivars such as Klara may be considered for phytostabilisation and rhizofiltration due to higher Cu, Zn, and Ni accumulation in roots. Vetiveria zizanoides demonstrated resistance to As stress and feasibility for the remediation of As. Moreover, bioindicators offer a feasible tool for recovering valuable elements for the development of a circular economy (e.g., rare earth elements).

The sustainability of transportation biofuel production value chains is under discussion as a consequence of the implementation of the European Union Bioeconomy Strategy and renewable energy production. Greenhouse gas emissions from the biomass produced for biofuel, and the energy required during the production process are, in many cases, greater than the emission reductions from the biofuels that are produced and used to replace fossil fuels. In this study, the sustainability of bioethanol production from short rotation coppice Salix schwerinii was considered from cultivation and harvesting to biofuel production and distribution. The sustainability of the full value chain was evaluated according to the European Union Renewable Energy Directive and calculations of greenhouse gas emission savings (%) from biofuel production were compared to a reference fossil fuel (gasoline). For comparison, four bioethanol production scenarios were developed, and specific attention was focused on the utilization of waste-based organic fertilizers (for biomass production) and on carbon dioxide capture at the fermentation stage, and their effects on value chain greenhouse gas emissions. Based on our evaluation, Salix bioethanol production achieved 60% emission savings compared to the fossil reference (requirement for installations that will commence operations until end of December 2020). When waste based organic fertilizers were used in the Salix biomass production, 65% emission savings were achieved (requirement for the installations that will commence operations from 2021). Moreover, the value chain sustainability and greenhouse gas emissions balance were improved by the carbon dioxide captured during the bioethanol fermentation stage.

Salix schwerinii was tested in a pot experiment to assess plant growth performance i.e., relative height and dry biomass and the potential for heavy metal uptake in soils polluted with chromium, zinc, copper, nickel and total petroleum hydrocarbons. The soil used in the pot experiment was collected from a landfill area in Finland. Peat soil was added at different quantities to the polluted soil to stimulate plant growth. The plants were irrigated with tap water or processed water (municipal waste water) to further investigate the effects of nutrient loading on plant biomass growth. The soil was treated at two pH levels (4 and 6). The results showed that the addition of 40–70% peat soil at pH 6 to a polluted soil, and irrigation with processed water accelerated plant growth and phytoextraction efficiency. In the pot experiment, Salix grown in chromium, zinc, copper, nickel and total petroleum hydrocarbons -contaminated field soil for 141 days were unaffected by the contaminated soil and took up excess nutrients from the soil and water. Total mean chromium concentration in the plant organs ranged from 17.05 to 250.45 mg kg −1 , mean zinc concentration ranged from 142.32 to 1616.59 mg kg −1 , mean copper concentration ranged from 12.11 to 223.74 mg kg −1 and mean nickel concentration ranged from 10.11 to 75.90 mg kg −1 . Mean chromium concentration in the plant organs ranged from 46 to 94%, mean zinc concentration ranged from 44 to 76%, mean copper concentration ranged from 19 to 54% and mean nickel concentration ranged from 8 to 21% across all treatments. Under the different treatments, chromium was taken up by Salix in the largest quantities, followed by zinc, copper and nickel respectively. Salix also produced a moderate reduction in total petroleum total petroleum hydrocarbons in the polluted soil. The results from the pot experiment suggest that Salix schwerinii has the potential to accumulate significant amounts of chromium, zinc, copper and nickel. However, long term research is needed to verify the phytoextraction abilities of Salix observed in the pot experiment.

In this study, the utilization of silicalite–1 membrane pervaporation for butanol recovery from an acetone-butanol-ethanol (ABE) fermentation broth solution was investigated. In particular, the negative effect of butyric acid on the pervaporation performance was tested. The presence of butyric acid was observed to decrease both the butanol flux and selectivity of the membrane. Clear relation between the severity of the decreased performance and the amount of butyric acid was observed. Increasing the pH of the feed solution was observed to improve butanol pervaporation in the presence of butyric acid. In pervaporation of ethanol, butanol and butyric acid, there are significant interactions in adsorption and diffusion between the components. The presence of butanol restricts the permeation of ethanol while the butanol permeation is restricted by the presence of butyric acid. The effects likely arise from adsorptive competition and are further amplified due to the rates of diffusion. In addition, butyric acid exposure may change the membrane properties over time, although they may be restored by heating. The results suggest that the selective recovery of butanol with a silicalite–1 membrane is not feasible if the concentration of butyric acid is significant and the pH value in the solution is low.

Rhizophora spp. are grown for wood charcoal production in many tropical estuaries and coastal areas. However, a lack of species-level information stands in the way of promoting this resource for sustainable practices. The present study investigated management practices and aboveground biomass (AGB) production patterns of Rhizophora apiculata plantations in the Yeesarn area of Samut Songkhram Province, Central Thailand. Interviews of farmers and a field survey were main instruments for collecting and analyzing of the data. It was found that farmers collect mature propagules locally and use traditional knowledge for maintenance of the plantation including site preparation and planting. Beating-up and weeding are the main operations applied in establishing a plantation; otherwise, little effort is directed towards post-planting maintenance. The plantation was reforested in a harvesting rotation of 8 to 15 years. Observed stand growth in terms of annual turnover rate (ATR) of height and diameter was highest in a 12-year old plantation; 0.82 m/year and 0.46 cm/year, respectively. Highest AGB production, stem wood volume (SWV), and commercial wood volume (CWV) were observed in a 14-year old plantation; 201.95 tonnes/ha, 181.49 m3/ha, and 178.98 m3/ha, respectively. Growth and productivity patterns indicate that the plantation has a high yield potential in terms of wood biomass production.

This study aims to improve acetone-butanol-ethanol production from the hydrolysates of lignocellulosic material by supplementing starchy slurry as nutrients. In the fermentations of glucose, xylose and the hydrolysates of Salix schwerinii, the normal supplements such as buffer, minerals, and vitamins solutions were replaced with the barley starchy slurry. The ABE production was increased from 0.86 to 14.7 g/L by supplementation of starchy slurry in the fermentation of xylose and the utilization of xylose increased from 29% to 81%. In the fermentations of hemicellulosic and enzymatic hydrolysates from S. schwerinii, the ABE yields were increased from 0 and 0.26 to 0.35 and 0.33 g/g sugars, respectively. The results suggested that the starchy slurry supplied the essential nutrients for ABE fermentation. The starchy slurry as supplement could improve the ABE production from both hemicellulosic and cellulosic hydrolysate of lignocelluloses, and it is particularly helpful for enhancing the utilization of xylose from hemicelluloses., final draft, peerReviewed