Biochar最新文献

Living wall systems (LWSs) help to alleviate the climate and biodiversity harms associated with buildings and bring benefits to building occupants. Their performance can be variable and existing research points to the planting substrate as a key design factor. This study provides quantitative evidence on the physical, thermal and moisture performance of three planting substrates that vary according to the proportion of biochar added to green waste compost (GWC). Thermal conductivity (Wm^-1 K^-1), thermal resistivity (mK W^-1), volumetric moisture content (%) and mass (g) are measured for each fraction, replicated six times. Controlled drying procedures were employed, measuring these properties at a range of moisture levels. Data analysis finds that volumetric moisture content and biochar fraction have a statistically significant (p ≤ 0.05) effect on thermal conductivity. Added biochar is associated with non-linear reductions in thermal conductivity at low moisture levels. This suggests increasing the biochar fraction while reducing moisture in the substrate of a LWS will reduce its thermal conductivity, with a 100 mm planting substrate with 30% biochar and 30%vol moisture content providing 0.82 m² KW^-1 of thermal resistance, compared to 0.46 m² KW^-1 without added biochar. The methods build on previous work to assess the properties of different planting substrates for LWSs, providing a practical, lab-based assessment of biochar. The data produced are useful for researchers and professionals seeking to understand how biochar additions impact irrigation and thermal performance when specifying and designing LWSs and underline the potential value of biochar for improving the thermal performance of green infrastructure more widely.

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Sandy soils, with inherently low water retention and poor hydraulic properties, present significant challenges for sustainable agriculture, particularly in water-limited conditions. This study investigates the impact of biochar, sludge, and compost amendments on the soil hydraulic properties and water balance of a sandy soil. A 441-day lysimeter experiment evaluated six treatments: biochar (A), sludge (B), compost (C), biochar + sludge (D), biochar + compost (E), and biochar + sludge + compost (F). Results showed that combined treatments outperformed single amendments, with treatment F (biochar + sludge + compost) exhibiting the most pronounced improvements in soil water dynamics. This treatment reduced cumulative drainage by over 40% relative to individual amendments and exhibited higher average soil water content and more stable water storage across seasonal fluctuations. Biochar addition enhanced soil porosity and water-holding capacity, while compost and sludge improved retention through organic matter input and fine particle contributions. Treatments containing biochar reduced drainage and increased actual evaporation, indicating improved soil water retention and availability. Saturated hydraulic conductivity, field capacity, and plant available water were closely correlated with observed drainage behavior, confirming the functional relevance of these soil hydraulic indicators. Statistical analyses, including one-way ANOVA and Tukey's HSD, supported the significance of treatment differences in drainage and actual evaporation. Overall, the study demonstrates that integrating biochar, compost, and sludge can synergistically enhance water retention, reduce drainage, and stabilize soil water contents in sandy soils. These findings offer practical insights for improving water use efficiency and resilience in arid and semi-arid agroecosystems.

Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00509-4.

The agricultural sector urgently requires scalable solutions to reduce greenhouse gas (GHG) emissions from residue management. Biochar offers a promising carbon removal pathway, but its adoption is limited by technical, regulatory, and economic barriers. A key constraint is the lack of system designs that can accommodate multiple feedstocks while complying with land application regulations. This study designs and evaluates an integrated biochar production system that enables the separate processing of straw and manure through parallel pyrolysis lines, while optimising internal energy use. Environmental and economic assessments were conducted using a case study of the University of Leeds Research Farm, under a cradle-to-grave system boundary. The results show that the system can produce 300 t of biochar annually, sequester 350 t CO₂e, and reduce manure management emissions by 75%, with an additional 30 t CO₂e avoided through surplus heat utilisation. The carbon abatement cost is estimated at £226 per t CO₂e, primarily driven by capital (38%), operational (32%), and electricity (30%) costs. Sensitivity analysis highlights that straw availability, determined by both yield and crop rotation, is the primary factor influencing system performance. Among the mitigation strategies for addressing heat shortfalls, procuring external straw is identified as the most effective option. This study presents a novel and adaptable system framework for on-farm biochar deployment, addressing key barriers to implementation. The findings provide quantitative insights into the trade-offs between cost, carbon removal, and design decisions, and offer a foundation for scaling biochar use across the agricultural sector.

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Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00527-2.

Biochar is widely recognised as a carbon dioxide removal (CDR) technology, but its stability depends on feedstock, pyrolysis conditions, and the soil environment. Current CDR schemes prioritise highly stable biochars to ensure long-term permanence, requiring high pyrolysis temperatures that reduce carbon yield and intensify competition for biomass. This perspective explores potential synergies between two distinct CDR approaches, biochar application and peatland rewetting, where rewetted peatlands could enhance biochar permanence by suppressing microbial decomposition, offering a means to improve both carbon retention and resource efficiency. Using decomposition rate modifiers from biogeochemical models, we estimate biochar stability in rewetted peat and assess its CDR efficiency relative to a counterfactual of high-stability biochar application to dry soils. This perspective suggests that rewetted peatlands significantly reduce biochar carbon losses, particularly for lower-stability biochars, making them more viable for long-term CDR. By allowing greater flexibility in biochar selection, this approach could improve the scalability of biochar deployment while alleviating biomass supply constraints. While challenges such as land-use transitions and methane emissions must be addressed, integrating biochar with peatland rewetting presents a high-impact strategy to optimise the efficiency of biomass-based CDR.

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Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00524-5.

Biochar has high potential for long-term atmospheric carbon storage in terrestrial environments, contributing to meeting the UK and global greenhouse gas emission reduction targets. This study investigates the greenhouse gas emissions and techno-economics associated with biochar produced from food waste anaerobic digestate using hydrothermal carbonisation followed by high-temperature post carbonisation. Owing to high moisture contents, digestates are challenging to valorise. However, these low-value feedstocks have steady availability with minimal competition for other applications. The study focuses on food waste digestate supply, biochar production, biochar agricultural field application, and transportation activities. Minimising digestate transport through co-locating biochar production facilities with anaerobic digestion displayed greenhouse gas mitigation costs of < £100 tCO₂eq^-1 (125 USD tCO₂eq^-1). The 88% stable carbon fraction of the biochar, which is resistant to degradation in soil, is primarily responsible for the effective removal of atmospheric greenhouse gases. This results in net emissions reductions of 1.15-1.20 tCO₂eq per tonne of biochar, predominantly due to the long-term storage of durable carbon (1.7 tCO₂eq per tonne of biochar). Using 50% of the UK's projected available food waste digestate by 2030 offers a sequester potential of 93 ktCO₂eq p.a., requiring 28 biochar facilities at 20 kt p.a. capacity. Sensitivity analysis emphasises the influence of the gate fee charged to process digestate, highlighting its importance for economic success of the biochar production. Further studies are needed to investigate the potential technology enhancements to reduce fossil-fuel use and provide greater certainty of the co-benefits of biochar application in agricultural soil.

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Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00456-0.

The draining and conversion of peatlands for agriculture has led to their degradation globally, diminishing their carbon (C) storage capacity and functioning. However, rewetting, alongside the addition of organic/inorganic amendments, has the potential to accelerate peat formation and C accrual. The aim of this experiment was therefore to examine the combined benefits of altering water table depth and adding organic (e.g., biochar, paper waste, biosolids, cereal straw; 20 t C ha^-1) and inorganic (e.g., FeSO₄; 0.5 t ha^-1) materials on net C storage and peatland functioning (i.e., microbial communities, greenhouse gas emissions and biogeochemical cycling). The experiment consisted of outdoor agricultural peat mesocosms monitored over 1 year. The relative effectiveness of the amendments in preserving peat-C (t C ha^-1) followed the series: Miscanthus biochar (18.9 t C ha^-1) > Miscanthus residues (17.3 t C ha^-1) > biosolids (17.2 t C ha^-1) > cereal straw (14.5 t C ha^-1) > paper waste (13.3 t C ha^-1) based on C additional rate (20 t C ha^-1). Overall, a high-water table combined with biochar and FeSO₄ addition was the most effective at suppressing enzyme activity (e.g., β-glucosidase, phenol oxidase, cellobiase), methanogen activity (e.g., Methanosarcina) and peat mineralization rate. We ascribe this in part to changes in the fungal and bacterial community structure (e.g., reductions in Actinobacteria by - 22% and Ascomycota by - 61%). FeSO₄ also increased the Fe-bound C content in the non-rewetted treatment, supporting the 'iron gate' mechanism for C preservation. The mechanisms behind our results appear to be both abiotic (affecting SOC solubility through changes in redox conditions and Fe-C interactions) and biotic (via shifts in microbial community and enzyme activities), creating conditions that enhance C preservation. These findings provide evidence for implementing biochar and FeSO₄ amendments alongside water table management as practical, scalable strategies for restoring C storage capacity in agricultural peatlands.

Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00501-y.

Biochar is a carbon-rich material produced through the pyrolysis of various feedstocks. It can be further modified to enhance its properties and is referred to as modified biochar (MB). The research interest in MB application in soil has been on the surge over the past decade. However, the potential benefits of MB are considerable, and its efficiency can be subject to various influencing factors. For instance, unknown physicochemical characteristics, outdated analytical techniques, and a limited understanding of soil factors that could impact its effectiveness after application. This paper reviewed the recent literature pertaining to MB and its evolved physicochemical characteristics to provide a comprehensive understanding beyond synthesis techniques. These include surface area, porosity, alkalinity, pH, elemental composition, and functional groups. Furthermore, it explored innovative analytical methods for characterizing these properties and evaluating their effectiveness in soil applications. In addition to exploring the potential benefits and limitations of utilizing MB as a soil amendment, this article delved into the soil factors that influence its efficacy, along with the latest research findings and advancements in MB technology. Overall, this study will facilitate the synthesis of current knowledge and the identification of gaps in our understanding of MB.

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Despite their high agricultural productivity, drained and cultivated peats are highly susceptible to degradation and significant sources of greenhouse gas (GHG) emissions. This study investigates the potential of water table manipulation and biochar application to mitigate GHG losses from agricultural peats. However, balancing the need for agricultural production with securing the ecosystem function of the peat under high water table (WT) conditions poses a significant challenge. Therefore, we grew lettuce in a controlled mesocosm experiment with either a high (HW) or low (LW) water table and monitored emissions of CO₂, CH₄ and N₂O over 4 months using a mesocosm method. Concurrent measurements of soil solution, plant measurements and microbial sequencing allowed identification of the key controls on GHG emissions. Raising the WT significantly reduced CO₂ emissions (18%), and N₂O emission (40%), but eventually increased CH₄ emission (2.5-fold) compared to the Control + LW. Biochar amendment with raised WT provided the strongest reduction in CO₂ equivalent GHG emission (4.64 t CO₂eq ha^-1 yr^-1), compared to Control + LW. We found that biochar amendment modified the microbial community composition and diversity (Shannon index 8.9-9.3), lowering the relative abundance of peat decomposers (such as Ascomycota). Moreover, biochar amendments produced 38-56% greater lettuce biomass compared to the unamended controls, irrespective of water table level, suggesting that biochar application could generate economic benefits in addition to reduced GHG emissions. Mechanisms responsible for these effects appeared to be both abiotic (e.g. via effects of the biochar physicochemical composition) and biotic via changing the soil microbiome. Overall, the combination of high-water table and biochar amendment enhanced total soil C, reduced peat decomposition, suppressed CH₄ and N₂O emissions, and enhanced crop yields.

Supplementary information: The online version contains supplementary material available at 10.1007/s42773-025-00487-7.

Peatlands are an important natural store of carbon (C). Drainage of lowland peatlands for agriculture and the subsequent loss of anaerobic conditions had turned these C stores into major emitters of greenhouse gases (GHGs). Practical management strategies are needed to reduce these emissions, and ideally to reverse them to achieve net GHG removal (GGR). Here we show that a combination of enhanced C input as recalcitrant organic matter, CH₄ suppression by addition of terminal electron acceptors, and suppression of decomposition by raising water levels has the potential to achieve GGR in agricultural peat. We measured GHG (CO₂, N₂O, and CH₄) fluxes for 1 year with intensive sampling (6 times within the first 56 days) followed by monthly sampling in outdoor mesocosms with high (0 cm) and low (- 40 cm) water table treatments and five contrasting organic amendments (Miscanthus-derived biochar, Miscanthus chip, paper waste, biosolids, and barley straw) were applied to high water table cores, with and without iron sulphate (FeSO₄). Biochar produced the strongest net soil C gain, suppressing both peat decomposition and CH₄ emissions. No other organic amendment generated similar GGR, due to higher decomposition and CH₄ production. FeSO₄ application further suppressed CO₂ and CH₄ release following biochar addition. While we did not account for life-cycle emissions of biochar production, or its longer-term stability, our results suggest that biochar addition to re-wetted peatlands could be an effective climate mitigation strategy.

Supplementary information: The online version contains supplementary material available at 10.1007/s42773-024-00422-2.

Biochar, produced from the thermochemical conversion of biomass waste, has various applications owing to its broad utility and advantageous properties. This study employs a scientometric approach to comprehensively assess the advancements in biochar application from 2022 to 2023. Utilizing 13,357 bibliographic records sourced from the Web of Science Core Collection with the search term “biochar”, the analysis focuses on authorship, national contributions, and keyword trends. Findings demonstrate a continual rise in annual publications since 2009, albeit with a moderated growth rate in 2023. China leads in publication outputs, followed by USA and India, with Hailong Wang emerging as a prominent figure in biochar research. Keyword co-occurrence analyses identify key research themes such as biochar’s role in climate change mitigation, easing salinity and drought stress, immobilizing toxic metals, degrading organic pollutants, serving as additives in anaerobic digestion, and functioning as electrodes in microbial fuel cells. Among these, biochar’s application for global climate change mitigation gains significant attention, while its utilization as electrodes in microbial fuel cells emerges as a promising research frontier, indicating the growing need for sustainable energy sources. The study also outlines critical research gaps and future priorities for enhancing biochar application. Overall, it highlights the diverse applicability of biochar and offers valuable insight into research progression and forthcoming directions in biochar studies.

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