Global Change Biology Bioenergy最新文献

Short rotation coppice (SRC) willow is a second-generation lignocellulosic energy crop with a background of research and breeding programmes carried out globally for more than three decades. While commercial standards include planting in mixtures of 6–8 willow genotypes of genetic diversity, much research to date has focused on monoculture trials. Research has found significant differences in willow performance through different management methods, soil properties and environmental interactions (GxE), when applied locally. However, global analysis of these interactions remains a challenge. We present a global SRC willow dataset to facilitate researchers and growers with a resource not available to date to help in closing the gap between research and industry. Data has been collected through literature review and personal communications with key researchers on willow in the United Kingdom. Global annual average yield is 9 Mg Dry Matter (DM) ha⁻¹ year⁻¹ with 17 genotypes, including two types of mixtures, above the economic threshold of 10 Mg DM ha⁻¹ year⁻¹. Canada and the United States are the best and worst performers with 10.6 and 6.7 Mg DM hr⁻¹ year⁻¹, respectively. We expect this dataset to provide an efficient way of estimating yields at a smaller scale by multiple combinations of GxE interactions. Biomass production from 1-year-old stems in the first harvest cycle is significantly lower than for the second and third year of the first harvest cycle (ANOVA, p < 0.001). Harvest cycles of 2 and 3 years did show significant but small differences in final yield (t = 3.87, p < 0.001). A random forest statistical procedure was applied to test for the association of the predictor variables with biomass production. The model explained up to 63.65% of the variance observed in yield for all genotypes and sites, with genetic diversity among the most important variables.

Methanol, a sustainable and abundant one-carbon (C1) feedstock, has emerged as a promising raw material for green biomanufacturing, offering a pathway to carbon neutrality. Natural methylotrophic yeasts such as Pichia pastoris (syn. Komagataella phaffii) and Ogataea polymorpha are increasingly recognized as attractive hosts due to their high methanol utilization rates and established roles in industrial protein and chemical production. However, their large-scale application faces critical challenges, such as low methanol assimilation efficiency, carbon loss, and methanol toxicity. This review highlights recent progress in the engineering of natural methanol cell factories, with a focus on strategies to overcome these bottlenecks. Topics include engineering the methanol assimilation and dissimilation pathways, adaptive laboratory evolution, metabolic compartmentalization, and C1/Cn cosubstrate utilization. By addressing these challenges and exploring innovative approaches, natural methylotrophic yeasts can be further developed as efficient platforms for methanol-based biomanufacturing, thus accelerating progress toward sustainable and carbon-neutral industrial processes.

Many policies for reducing the emissions intensity of transportation fuels rely on the outputs of life-cycle assessment (LCA) models to incentivize the production of biofuels and other alternative fuels. This approach is essential to account for greenhouse gas emissions, sequestration, and avoidance throughout the supply chain and use of each fuel. Since the creation of the United States' Renewable Fuel Standard and California's Low Carbon Fuel Standard, there has been broader adoption of LCA-based regulations and incentives, accompanied by an evolution in modeling approaches. There is general agreement that regulatory impact assessment and policy design/implementation are distinct, where the latter benefits from transparent models that capture clear cause-and-effect relationships between measures taken to reduce emissions and a fuel's carbon intensity score. However, there is not yet convergence on a range of methodological choices that impact LCA outputs relevant for fuels and a host of other emerging applications, such as private carbon markets. Numerous recent studies have explored existing LCA methods and developed new approaches for applications where consensus has not yet been reached, such as soil organic carbon accounting, forest biomass carbon accounting, crediting of avoided emissions, and defining wastes. Simultaneously, new and revised LCA-based biofuel policies have leveraged these approaches, and in some cases, used fit-for-purpose solutions. This article reviews the state of policy-relevant biofuel LCA methods and tools, compares and contrasts established and emerging approaches within current policies at the state, federal, and international levels, and identifies key challenges that require further research and coordination to establish best practices. These issues have implications beyond biofuel policies, extending to power generation and carbon dioxide removal crediting.

Biogas, a renewable energy source produced from the anaerobic digestion of biomass and/or organic residues, contains a mixture of methane (CH₄) and carbon dioxide (CO₂). To be used as a fuel, biogas must be upgraded to increase its CH₄ content to over 90%. Traditional upgrading methods, such as amine scrubbing and membrane separation, are energy-intensive, costly, and environmentally burdensome. This study explores the potential of electrochemical technologies as sustainable alternatives for biogas upgrading from the aspects of energy, environment, economics, and engineering. Recent advances in promising electrochemical approaches including pretreatment, microbial conversion enhancement, CO₂ capture, CO₂ reduction reactions, and methanation are first reviewed. The performance of these approaches is then systematically compared based on operational characteristics and efficiency metrics. Our findings indicate that microbial and bioelectrochemical systems can achieve CH₄ purities over 92%. Also, electrochemical technologies offer > 99.9% hydrogen sulfide removal (desulfurization). State-of-the-art electrochemical CO₂ reduction technologies demonstrate Faradaic efficiencies generally 50%–80%, with the selectivity of CH₄ up to 99.7%. From the environmental aspect, integrating renewable electricity into microbial, electrochemical (or -based), and bioelectrochemical upgrading systems yields roughly 10%–74% life-cycle GHG reductions relative to conventional fossil-energy pathways, with certain renewable power-to-methane configurations achieving net-negative emissions. Lastly, this study identifies several priority research directions, such as (1) advanced catalyst and electrode development, (2) system integrations with air pollutant control facilities, (3) life-cycle environmental and techno-economic assessment, and (4) digestate valorization for multiple product ecosystems. Electrochemical approaches offer a promising path toward clean, efficient, and decentralized biogas utilization, contributing to global decarbonization and energy transition goals toward a circular bioeconomy.

Cardoon (Cynara cardunculus var. altilis) is a promising perennial energy crop for Mediterranean areas. Implementing temporary intercropping with selected species during the long establishment phase of the cardoon can enhance ecosystem services by promoting crop diversification, suppressing weeds, and increasing biomass production. A three-year field experiment conducted in Sardinia, Italy, compared three intercropping systems: (i) rocket (Eruca sativa), (ii) camelina (Camelina sativa), and (iii) hairy vetch (Vicia villosa) with a monocropped control. The study assessed the effects of temporary intercropping on weed suppression and cardoon development and production. The biomass production of the intercropped species was also measured. Temporary intercropping reduced weed biomass by 24.2% on average (compared to the control) without hindering cardoon establishment in the first year of cultivation. V. villosa and E. sativa were the most competitive against the main weeds. V. villosa had the highest yield. Temporary intercropping with V. villosa, in the following year after its establishment, increased cardoon production by an average of 55.1% compared to the other intercropped species.

Bioenergy and bioproduct markets are expanding to meet demand for climate-friendly goods and services. Perennial biomass crops are particularly well suited for this goal because of their high yields, low input requirements, and potential to increase soil carbon (C). However, it is unclear how much C is allocated into belowground pools by perennial bioenergy crops and whether the belowground benefits vary with nitrogen (N) fertilizer inputs. Using in situ ¹³C pulse-chase labeling, we tested whether the sterile perennial grass Miscanthus × giganteus (miscanthus) or annual maize transfers more photosynthetic C to belowground pools. The experiment took place at two sites in Central and Northwest (NW) Iowa with different management histories and two nitrogen (N) fertilizer rates (0 and 224 kg N ha⁻¹ year⁻¹) to determine if the fate of plant-derived soil C depends on soil fertility and crop type (perennial or annual). Maize allocated a greater percentage of total new ¹³C to roots than miscanthus, but miscanthus had greater new ¹³C in total and belowground plant biomass. We found strong interactions between site and most soil measurements—including new ¹³C in mineral and particulate soil organic matter (SOM) pools—which appears to be driven by differences in historical fertilizer management. The NW Iowa site, with a history of manure inputs, had greater plant-available nutrients (phosphorus, potassium, and ammonium) in soils, and resulted in less ¹³C from miscanthus in SOM pools compared to maize (approximately 64% less in POM and 70% less in MAOM). In more nutrient-limited soils (Central site), miscanthus transferred 4.5 times more ¹³C than maize to the more stable mineral-associated SOM pool. Our results suggest that past management, including historical manure inputs that affect a site's soil fertility, can influence the net C benefits of bioenergy crops.

The expansion of sugarcane onto land currently occupied by improved (IMP) and semi-native (SN) pastures will reshape the U.S. bioenergy landscape. We combined biometric, ground-based and eddy covariance methods to investigate the impact of sugarcane expansion across subtropical Florida on the carbon (C) budget over a 3-year rotation. With 2.3- and 5.1-fold increase in productivity over IMP and SN pastures, sugarcane displayed a C use efficiency (CUE; i.e., fraction of gross C uptake allocated to plant growth) of 0.59, well above that of pastures (0.31–0.23). Sugarcane also had greater C allocation to aboveground productivity and hence, harvestable biomass relative to IMP and SN. Cane heterotrophic respiration over the 3-year rotation (903 ± 335 gC m⁻² year⁻¹) was 1% and 14% higher than IMP and SN pastures, respectively. These soil C losses responded largely to disturbance over the first year after conversion (1510 ± 227 gC m⁻² year⁻¹) but declined in subsequent years to an average 599 ± 90 gC m⁻² year⁻¹—well below those of IMP (933 ± 140 gC m⁻² year⁻¹) and SN (759 ± 114 gC m⁻² year⁻¹) pastures—despite a significant 40%–61% increase in soil C inputs. Soil C inputs, however, shifted from root-dominated in pastures to litter-dominated in sugarcane, with only 5% C allocation to roots. Reduced decomposition rates in sugarcane were likely driven by changes in the recalcitrance and distribution rather than the size of the newly incorporated soil C pool. As a result, we observed a rapid shift in the net ecosystem C balance (NECB) of sugarcane from a large source immediately following conversion to approaching the net C losses of IMP pastures only 2 years after conversion. The environmental cost of converting pasture to sugarcane underscores the importance of implementing management practices to harness the soil C storage potential of sugarcane in advancing a sustainable bioeconomy in Southeastern United States.

The global demand for biomass-based products, including biofuels and biomaterials, is projected to rise significantly in the coming decades, driven by climate change mitigation and the pursuit of energy independence. Expanding biomass production systems, such as short-rotation plantations and energy grasses, offers a promising option to meet this demand. Although these systems deliver environmental benefits, such as carbon sequestration and water purification, their large-scale implementation may lead to landscape homogenization. Conversely, strategically deployed biomass systems can enhance local land use diversity, support biodiversity, and generate mixed income opportunities for farmers. In this study, we present a harmonized analysis of European biomass production systems using spatial data from over 426,783 fields and stands, covering 2,140,568 ha across 17 countries. By integrating empirical data with landscape metrics, we assess the spatial distribution, scale, and land use context of diverse biomass systems ranging from short-rotation plantations to energy grasses. Our results show that depending on their location, biomass production systems have the potential to enhance local land use diversity and support multifunctional landscapes that mitigate the risks associated with large-scale monocultures. Conversely, poorly integrated systems may lead to landscape homogenization and reduced ecological resilience. These findings provide a baseline for crop species selection and spatial planning, thereby informing land use policies that harmonize bioenergy production with environmental sustainability.

Moso bamboo (Phyllostachys edulis) forests play a significant role in carbon sequestration, but their sustainability is threatened by nutrient depletion and greenhouse gas (GHG) emissions. This study aims to evaluate fertilization strategies that optimize both economic returns and environmental protection in these forests. A 1-year field experiment (three treatments with four replicates) was conducted to examine the effects of biochar and chemical fertilizer application on soil carbon and nitrogen pools, microbial community composition, ecosystem carbon stock, and GHG fluxes in a subtropical Moso bamboo forest. Biochar-based compound fertilizer application increased soil organic carbon (SOC) by 12.6%, reduced microbial residual carbon (MRC) by 8.2%, and enhanced CH₄ absorption by 22.4%. In addition, it decreased N₂O emissions by 16.5%. In contrast, chemical fertilizer increased short-term biomass productivity (24.8%) but resulted in higher CO₂ and N₂O emissions. Neither treatment significantly affected microbial α-diversity, but both altered microbial community composition, particularly fungi, with biochar favoring beneficial fungal species. Biochar-based compound fertilizer is a promising strategy for enhancing carbon sequestration and mitigating GHG emissions in Moso bamboo forests. These findings highlight biochar's potential to improve soil health and contribute to more sustainable bamboo forest management, offering valuable insights for climate change mitigation strategies.

Manure and biochar (BC) based practices influence soil carbon (C) dynamics. However, manure does not enhance soil carbon (C) as quickly as BC does. Data on BC from different feedstocks and their co-application with manure in stabilizing labile manure C fractions in soil systems is still inadequate. We hypothesize that manure-BC co-application will increase soil total C by influencing the microbial community, likely to increase labile and recalcitrant C than manure alone. This study evaluated several stability parameters of manure (swine and dairy) under four rates of different BC (herbaceous corn stover, woody yellow pine, and willow) following 1 month of aging. These aged mixtures were applied to the soil and incubated for 203 days to fit a two-pool model, and the soil labile C residence time was determined. A significant (p < 0.05) positive correlation between ash-free volatile solids: fixed solids and molar H:C_org and O:C_org supports that BC addition generally stabilizes manure C by changing the mixture's physicochemical properties. Hot water extracted C of the fresh and aged mixtures revealed that high BC addition rates and BC produced from wood are significantly (p < 0.05) more efficient in decreasing the labile C pool than untreated manure, low BC application rates, and herbaceous BC. Soil incubation study revealed that BC rate significantly (p < 0.05) reduced ammonium-N availability, labile C release, and respirational C loss, but increased soil recalcitrant-C. This study reports that manure type and BC application rate significantly (p < 0.0001) influence microbial biomass C, and co-application was harmless to microbes, which in turn influences the residence time of labile C. This laboratory-based study suggests that manure-BC addition to soil builds soil total C more consistently than manure alone, supporting our initial hypothesis. However, a field-based study is warranted to evaluate manure's C and N stability and nutrient release performances under dynamic soil conditions.