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Cited by 942Soil Carbon and Nitrogen DynamicsAgricultural Science and FertilizationThermochemical Biomass Conversion Processes

Biochar and its importance on nutrient dynamics in soil and plant

Open access
Hossain, Md Zahangir, Bahar, Md Mezbaul, Sarkar, Binoy, Donne, Scott Wilfred, Ok, Young Sik, Palansooriya, Kumuduni Niroshika, Kirkham, Mary Beth, Chowdhury, Saikat +1 more·2020·Biochar
DOI 10.1007/s42773-020-00065-z
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TL;DR

This review synthesizes how biochar affects nutrient dynamics in soil and plants, acting as a nutrient source, nutrient sink, and soil conditioner. It reports that outcomes depend strongly on feedstock, pyrolysis temperature, application rate, and soil type, with generally positive but variable effects on nutrient retention, leaching, gaseous losses, and crop nutrient uptake.

Key findings

  • Biochar nutrient contents vary widely: N ranges from 0.24 to 6.8%, and P from 0.005 to 5.9%; manure- and biosolid-based biochars generally contain more N and P than wood- and straw-based biochars. N content decreases with increasing pyrolysis temperature, while P and K contents increase due to ash concentration effects.
  • Biochar can reduce nutrient losses: NO₃⁻ leaching was reduced by 26% (Fig. 7), and a meta-analysis cited in the review showed about a 54% reduction in N₂O emissions with biochar application. N₂O-N emission factor and yield-scaled N₂O emissions were reduced by 16–67% and 14–53%, respectively (Li et al. 2017a). However, biochar could temporarily increase NH₃ volatilization by 19%.
  • Biochar alters soil properties relevant to nutrients: biochar pH ranges from 6.52 to 12.64 and correlates positively with pyrolysis temperature. Rice husk biochar at 3, 6, and 12 t ha⁻¹ increased water-stable aggregates by 10, 18, and 23%, respectively, at 0–10 cm in the first year; maize straw biochar at 10–60 t ha⁻¹ increased soil porosity from 42.5% to 48–56%.
  • Nutrient uptake and use efficiency responses are mostly positive but inconsistent: biochar increased N uptake by 11% (Fig. 7); P uptake increased by 23–2096% in some studies; NUE and PUE increased by 90 and 191%, respectively, with biochar up to 20 t ha⁻¹. Negative or neutral effects on N, Ca, Mg, and micronutrient uptake are also reported.

Methods

  • Narrative review synthesizing published literature on biochar production and characteristics, effects on soil physical, chemical, and biological properties, biochar as a nutrient source, and impacts on nutrient reactions, leaching, gaseous emission, uptake, and nutrient use efficiency.
  • The paper organizes evidence in Tables 1–6 and conceptual figures, drawing on cited studies across feedstocks, pyrolysis temperatures, soils, and crops.
  • No new primary experiment or formal meta-analysis is described; the review does not state a systematic literature search or selection protocol.

Limitations

  • The paper states future research recommendations rather than a formal limitations section: long-term field studies are needed instead of pot or column studies; feedstock selection and application rate should be studied in relation to nutrient availability; methods to increase biochar N content should be considered; P availability across pyrolysis temperatures needs study; and biochar–microbe interactions affecting nutrient transformation require further work.
  • Evident from the text: as a narrative review, it does not describe systematic search or quantitative synthesis methods, and it repeatedly notes inconsistent effects of biochar on N availability, Ca, Mg, and micronutrient uptake depending on biochar type, rate, soil, and crop.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1007/s42773-020-00065-z

Cites

285 of 285 references verified0 citation errors · 0 not checkable

Statistics

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Claims the paper makes

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  • Premisecitation

    Biochar can influence nutrients in soil as a soil conditioner, altering soil properties that influence the reactions and cycling of nutrients in the soil.

    “(iii) as a soil conditioner, thereby altering soil properties that influence the reactions and cycling of nutrients in the soil (Lusiba et al. 2017).”
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    Biochar can influence nutrients in soil as a nutrient sink, impacting the mobility and bioavailability of nutrients.

    “(ii) as a nutrient sink, thereby impacting the mobility and bioavailability of nutrients (Gul and Whalen 2016);”
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    The phosphorus and potassium contents of biochar increase with increasing pyrolytic temperature due to an increase in ash content.

    “the P and K contents increase due to an increase in ash content (Christel et al. 2016;Tomczyk et al. 2020;Wang et al. 2013).”
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    The nitrogen content of biochar decreases with increasing pyrolytic temperature through gaseous emission.

    “While the N content decreases with increasing pyrolytic temperature through gaseous emission (Leng et al. 2020)”
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    Some nitrogen and sulfur in feedstock materials are lost through gaseous emission during pyrolysis.

    “While some nitrogen and sulfur in the feedstock materials are lost through gaseous emission during pyrolysis (Al-Wabel et al. 2013;Leng et al. 2020)”
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    Premisecitation

    As a nutrient sink, biochar can retain nutrients, thereby reducing their losses through leaching and gaseous emission.

    “As a nutrient sink, biochar can retain nutrients, thereby reducing their losses through leaching and gaseous emission.”
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    Premisecitation

    Biochar application reduces the loss of nitrogen, phosphorus, and potassium through leaching, and nitrogen through nitrous oxide emission.

    “Biochar application reduces the loss of N, P, and K through leaching, and N through nitrous oxide emission (Beusch et al. 2019;Yao et al. 2012;Yuan et al. 2016).”
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    Loss of nitrogen through ammonia emission depends mainly on the pH of the biochar; biochar with a slightly acidic or near-neutral pH reduces ammonia volatilization from soil.

    “However, the loss of N through ammonia emission depends mainly on the pH of the biochar; biochar with a slightly acidic or near-neutral pH reduce ammonia volatilization from soil (Mandal et al. 2019;Mandal et al. 2018).”
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    Biochar application influences various soil properties including pH, bulk density, cation exchange capacity, water retention, and biological activity.

    “Biochar application influences various soil properties including pH, bulk density, cation exchange capacity, water retention, and biological activity.”
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    Interpretationreasoning

    Upon application to soil, biochar improves soil fertility and crop productivity by increasing soil nutrient contents and the mobility of nutrients.

    “Upon application to the soil, biochar improves soil fertility and crop productivity by increasing the soil nutrient contents and the mobility of nutrients.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Application of rice husk biochar at 10 t ha-1 increased soil porosity by decreasing bulk density and increased available water in a sandy clay loam soil.

    “Moreover, the application of rice husk biochar (10 t ha -1 ) increased soil porosity by decreasing bulk density and increased available water in a sandy clay loam soil (Laghari et al. 2016).”
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    Premisecitation

    Based on ash composition and properties, biochar can be divided into three main groups.

    “Based on the ash composition and its properties, biochar can be divided into the following three main groups (Joseph and Taylor 2014).”
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    Premisecitation

    Maize straw biochar reduced soil bulk density and improved soil porosity in a semi-arid region.

    “Li et al. (2018) said that maize straw biochar reduced soil bulk density and improved soil porosity in a semi-arid region.”
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    Premisecitation

    Biochar can change soil microbial community composition and thus impacts nutrient cycling and uptake by plants.

    “Biochar can change the soil microbial community composition (Ducey et al. 2013), and thus it impacts nutrient cycling and uptake by plants (Lehmann et al. 2011).”
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    Biochar improves aeration and water retention.

    “improves aeration, and water retention (Kambo and Dutta 2015;Razzaghi et al. 2020)”
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    Premisecitation

    Biochar produced from biomass with minimum ash content (<3-5%) has large porosity, surface area, and holds more water than biochars in other groups.

    “Biochar produced from biomass with minimum ash content (<3-5%), such as wood, nut shells, bamboo, and some seeds (e.g., apricots).These hard biochars have large porosity, surface area (SA), and hold more water than biochars in other groups.”
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    Premisecitation

    Under high-temperature pyrolytic conditions (>550°C), biochar is characterised by a large surface area and high aromaticity.

    “For example, under high-temperature pyrolytic conditions (>550° C), biochar is characterised by having a large surface area and a high aromaticity (Ralebitso-Senior and Orr 2016).”
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    Biochar is generally produced from a range of biomasses at temperatures less than 900 °C and under oxygen-limited pyrolytic conditions.

    “Generally, biochar is produced from a range of biomasses (e.g., manure, wood, crop, and industrial residues) at temperatures less than 900 °C and under oxygen-limited pyrolytic conditions (Zhang et al. 2019e).”
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    At pyrolysis under low temperatures (200-400°C), biochar is characterised by more oxygen-containing functional groups, which stimulate nutrient exchange and improve soil fertility.

    “However, at pyrolysis under low temperatures (200-400°C), biochar is characterised by having more oxygen-containing functional groups, such as -COOH, -OH, C=O, phenolic -OH and -CHO groups, which stimulate nutrient exchange and, thus, improve soil fertility (Mandal et al. 2020;Ralebitso-Senior and Orr 2016).”
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    Biochar decreases nitrification in soil, resulting in reduced nitrate leaching.

    “Biochar decreases nitrification in soil resulting in reduced nitrate leaching (Igalavithana et al. 2016).”
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    Premisecitation

    Biochar can also be produced by other thermochemical processes, including hydrothermal carbonization, gasification, torrefaction, and microwave-assisted pyrolysis.

    “However, recent studies have shown that biochar can also be produced by other thermochemical processes, e.g., hydrothermal carbonization, gasification, torrefaction, and microwave-assisted pyrolysis (Kambo and Dutta 2015;Vithanage et al. 2017;Yuan et al. 2017).”
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    Biochar is known to increase the organic carbon content in soil and stimulate carbon sequestration by suppressing the long-term turnover of soil organic matter.

    “Moreover, biochar is known to increase the organic carbon content in soil (Table 2) and stimulate C sequestration by suppressing the long-term turnover of soil organic matter (Schofield et al. 2019).”
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    Premisereasoning

    Soil pH can be altered by incorporation of biochar into soil, thereby contributing to alterations in nutrient availability.

    “Soil pH can be altered by incorporation of biochar into soil, thereby contributing to alterations in nutrient availability.”
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    Premisenone given

    Biochars generally have a pH range of 6.52-12.64, and pH values positively correlate with pyrolytic temperature.

    “Biochars generally have a pH range of 6.52-12.64(Table 4), and the pH values positively correlate with the pyrolytic temperature (Fig. 4).”
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    Premisecitation

    Biochar improved soil water retention, reduced bulk density, and stabilized soil organic matter.

    “Nair et al. (2017) observed that biochar improved soil water retention, reduced bulk density, and stabilized soil organic matter.”
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    Premisecitation

    Peanut-shell biochar (1%) increased microbial populations, microbial biomass, and actinomycetes.

    “Du et al. (2018) found that peanut-shell biochar (1%) increased microbial populations, microbial biomass, and actinomycetes.”
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    Premisecitation

    Various types of biochars produced from various feedstocks change the cation exchange capacity of soils to a different extent, and cation exchange capacity affects nutrient availability and water retention of soil.

    “Therefore, various types of biochars produced from various feedstocks change the CEC of soils to a different extent (Table 2), and the CEC affects nutrient availability and water retention of soil (Yadav et al. 2018).”
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    Premisecitation

    Biochar suppressed soil shrinkage by increasing the ability of the soil to hold water, thus improving soil structure.

    “and suppressed soil shrinkage by increasing the ability of the soil to hold water; thus, soil structure was improved (Fu et al. 2019).”
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    Premisecitation

    Biochar application shifted the bacterial community towards low carbon turnover bacterial taxa, which stabilised soil aggregates.

    “Zheng et al. (2018) also found a shift of the bacterial community towards low C turnover bacterial taxa (e.g., Actinobacteria and Deltaproteobacteria), which stabilised soil aggregates.”
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    Premisecitation

    Most biochars contain high amounts of soluble salts, and hence the electrical conductivity of biochar is generally higher than most agricultural soils.

    “Most biochars contain high amounts of soluble salts, and, hence, the EC of biochar is generally higher than most agricultural soils (Igalavithana et al. 2018).”
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    Premisecitation

    Biochar showed a positive impact on surface area of soil, which varied with biochar types.

    “Biochar also showed a positive impact on surface area of soil (Anawar et al. 2015), which varied with biochar types (Tomczyk et al. 2020).”
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    Premisereasoning

    Soil chemical properties influence nutrient interactions in soil.

    “These soil chemical properties influence nutrient interactions in soil.”
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    Interpretationcitation

    Variation in biochar's effects on soil microbial communities was suggested to be due to the toxic effect (chemical stress) of biochar on soil microorganisms when applied at a high rate.

    “The authors suggested that such variation of biochar's effects was due to the toxic effect (chemical stress) of biochar on soil microorganisms when applied at a high rate.”
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    Premisecitation

    In a coastal wetland soil, biochar application boosted the soil microbial biomass carbon and resulted in a low metabolic quotient.

    “For example, in a coastal wetland soil, biochar application boosted the soil microbial biomass C and resulted in a low metabolic quotient (Zheng et al. 2018).”
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    Premisecitation

    The effects of pyrolytic temperature on the sulfur content of biochars are inconsistent because high temperatures can either increase sulfur content by incorporation into complex structures or decrease sulfur content due to volatilization loss.

    “The effects of pyrolytic temperature on the S content of biochars are inconsistent (Table 4), because high temperatures can either increase S content by the incorporation of S into complex structures or decrease S content due to volatilization loss (Al-Wabel et al. 2013).”
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    Premisecitation

    Most biochars have low nitrogen content below 1.5%, but nitrogen content is high in a few biochars such as those derived from sewage sludge, poultry litter, grass waste, and microalgae.

    “Although, most biochars have low N content (below 1.5 %) (Table 4), the N content is high in a few biochars such as those derived from sewage sludge (6.8%), poultry litter (5.85%), grass waste (4.9%), and microalgae (14.12%) (Chang et al. 2015).”
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    Premisereasoning

    As in the case of phosphorus, potassium content of biochar increases with increasing pyrolytic temperature, which can be attributed to the concentration effect.

    “As in the case of P, K content of biochar also increases with increasing pyrolytic temperature (Fig. 5), which can be attributed to the 'concentration effect'.”
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    Premisecitation

    A continuous application of nitrogen in available forms is essential for many agricultural soils to maintain production in cropping seasons.

    “A continuous application of N in available forms is essential for many agricultural soils to maintain production in cropping seasons (Fageria and Baligar 2005).”
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    The effect of feedstock type and production temperature is not consistent for micronutrient contents of biochar products, which can be attributed mainly to the low micronutrient contents in feedstock materials.

    “However, the effect of these factors is not consistent for micronutrient contents of biochar products, which can be attributed mainly to the low micronutrient contents in feedstock materials.”
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    Premisecitation

    Poultry litter biochar had a negative short-term effect or no long-term effect on earthworm activity in soil, attributed to a rapid pH change or high ammonia concentration.

    “Similarly, Weyers and Spokas (2011) observed a negative effect (short-term) or no effect (long-term) of poultry litter biochar on earthworm activity in soil, which was attributed to a rapid pH change or high ammonia concentration in the soil due to the addition of the biochar (Liesch 2010).”
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    Premisereasoning

    While nitrogen content decreases with pyrolytic temperature, phosphorus content is positively correlated with pyrolytic temperature.

    “While the N content decreases with pyrolytic temperature, the P content is positively correlated with the pyrolytic temperature (Fig. 5).”
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    Premisecitation

    Biochar increased phosphorus-solubilizing bacterial populations, which contributed to improving phosphorus availability in a forest soil.

    “Biochar also increased P-solubilizing bacterial populations such as Burkholderia-Paraburkholderia, Planctomyces, Sphingomonas, and Singulisphaera, which contributed to improving P availability in a forest soil (mountain acidic red loam soil) (Zhou et al. 2020).”
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    Premisecitation

    The calcium contents of animal-manure biochar ranged from 0.40 to 6.15%, industrial and municipal waste-derived biochar from 0.37 to 6.57%, crop residue biochar from 0.20 to 1.57%, and woody biochar from 0.05 to 2.42%.

    “The Ca contents of animal-manure biochar ranged from 0.40 to 6.15% and that of industrial and municipal waste-derived biochar ranged from 0.37-6.57%(Table 4).Biochar derived from crop residues had concentrations of Ca ranging from 0.20-1.57%and that of woody biochar was in the range of 0.05-2.42%(Table 4).”
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    Interpretationreasoning

    Biochar can reduce ortho-P leaching from nutrient-rich soil and influences P availability.

    “So, biochar can reduce ortho-P leaching from nutrient-rich soil and influences P availability (Gul and Whalen 2016;Hussain et al. 2017).”
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    Interpretationcitation

    Availability of micronutrients is influenced by application of biochar to soil, and feedstock and type of soil are important in determining micronutrient availability.

    “The availability of micronutrients is influenced by the application of biochar to soil (Table 5), and feedstock and type of soil are important in determining micronutrient availability.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Addition of biochar increased NO3--N and NH4+-N retention in soil by 33 and 53%, respectively.

    “For instance, Gao et al. (2016) reported that addition of biochar increased NO3 --N and NH4 + -N retention in soil by 33 and 53%, respectively.”
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    Interpretationreasoning

    Availability of most nutrients are positively correlated with pyrolytic temperature, except N and S, because of volatilization loss.

    “Availability of most nutrients are positively correlated with the pyrolytic temperature, except N and S, and that is because of volatilization loss.”
    Quote in the paperNot a substantial claim

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    Interpretationreasoning

    The impact of biochar on P uptake is mostly positive and few studies show a negative impact.

    “The impact of biochar on P uptake is mostly positive and few studies show a negative impact (Table 6).”
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    Interpretationreasoning

    Biochar can be an important source of plant nutrients and can supply macro-nutrients, secondary nutrients, and micronutrients to plants.

    “Biochar can be an important source of plant nutrients and can supply macro-nutrients, secondary nutrients, and micronutrients to plants.”
    Quote in the paperSubstantial claim

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    Interpretationcitation

    Effects of biochar application on N availability in soil are not consistent; N availability is governed by rate and type of biochar and soil type.

    “Therefore, the effects of biochar application on N availability in soil are not consistent as the N availability is governed by rate and type of biochar as well as the soil type (Table 5).”
    Quote in the paperSubstantial claim

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    Interpretationcitation

    Usually availability of K in soil is increased with addition of biochar irrespective of study, although some negative impacts have been reported.

    “Usually the availability of K in soil is increased with the addition of biochar irrespective of the study, although some negative impacts of biochar on the availability of K in soil have been reported (Table 5).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Animal manures and waste-derived biochars have higher N, P, and K contents than crop residues and woody biochars.

    “Animal manures and waste-derived biochars have higher N, P, and K contents than crop residues and woody biochars.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    Application of biochar enhances nutrient retention by increasing the soil pH and soil organic matter.

    “Application of biochar also enhances nutrient retention by increasing the soil pH and soil organic matter (Mendez et al. 2012).”
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    Premisecitation

    Anion exchange capacities of biochar and its ability to retain ions and molecules within the pores further contribute to biochar's enhanced nutrient retention capacity.

    “Sorrenti et al. (2016) and anion exchange capacities of biochar and its ability to retain ions and molecules within the pores further contribute to biochar's enhanced nutrient retention capacity.”
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    Interpretationcitation

    Biochar can contribute to nutrient use efficiency in plants, both directly through increased nutrient uptake and indirectly by decreasing loss of nutrients through leaching and gaseous emissions.

    “Biochar can contribute to nutrient use efficiency in plants, both directly through increased nutrient uptake and indirectly by decreasing the loss of nutrients through leaching and gaseous emissions.”
    Quote in the paperSubstantial claim
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  • The paper relies on this without support.

    There is no review concerning the ability of biochar to retain multiple nutrients in soil through reducing gaseous and leaching losses and thus enhance plant growth.

    “However, there is no review concerning the ability of biochar to retain multiple nutrients in soil through reducing gaseous and leaching losses and, thus, enhance plant growth.”
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Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • High ash and low temperature biochars are suitable for soil fertility improvement.

    “Therefore, high ash and low temperature biochars are suitable for soil fertility improvement due to nutrient delivery and high labile carbon content (Hossain et al. 2020).”

    From Role of biochar toward carbon neutrality (2023) · cites this paper as Hossain et al. 2020

    The section on biochar characteristics (page unavailable) says low-temperature biochars have functional groups that stimulate nutrient exchange and improve soil fertility. The Introduction and §4.1.2 link ash-rich biochar with nutrient content, particularly phosphorus. The paper does not establish that high-ash, low-temperature biochars are suitable specifically because of high labile carbon content. (LLM, conf=0.84)

    Experimental — accuracy not yet measured

  • Ash-rich and animal waste-derived biochars, such as manure biochar, may be the best candidate for inorganic nutrient delivery.

    “In this case, ash-rich and animal waste-derived biochars, such as manure biochar may be the best candidate for inorganic nutrient delivery (Binh Thanh et al. 2022; Hossain et al. 2020; Subedi et al. 2016).”

    From Role of biochar toward carbon neutrality (2023) · cites this paper as Hossain et al. 2020

  • Biochar addition to agricultural soils has improved soil water availability, water holding capacity, nutrient availability, increased soil microbial biomass and activity, reduced risk of crust formation and soil erosion, enhanced antibacterial activity, and reduced mobility and toxicity of environmental pollutants.

    “Biochar addition to agricultural soils has improved soil water availability, water holding capacity, and nutrient availability,235, 236, 237 increased soil microbial biomass and activity,238 reduced risk of crust formation and soil erosion,239 enhanced antibacterial activity,240 and reduced mobility and toxicity of environmental pollutants in the soil.241,242”

    From Technologies and perspectives for achieving carbon neutrality (2021) · cites this paper as [236]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Figure 4 is cited for pH trends but captioned as nitrogen pathways

    Minor

    The text cites Figure 4 for the relationship between pH and pyrolytic temperature, but the Figure 4 caption identifies it as a diagram of nitrogen conversion pathways.

  • Stated biochar pH range excludes a tabulated value

    Minor

    The stated lower limit is 6.52, whereas Table 4 lists a chicken manure-Fe biochar with a pH of 5.72.

  • Stated biochar nitrogen range excludes a reported value

    Minor

    The stated nitrogen-content range ends at 6.8%, but the same paragraph reports 14.12% for microalgae-derived biochar.

  • Stated manure-biochar iron range excludes a tabulated value

    Minor

    The stated upper limit for iron in animal-manure biochar is 7,480 mg kg−1, but the table lists 74,800 mg kg−1 for swine-solids biochar.

  • Claim that biochar always reduces bulk density conflicts with Table 1

    Minor

    The text says biochar reduces bulk density regardless of conditions, but Table 1 gives identical control and amended bulk densities of 1.30 g cm−3 for the 3 t/ha green-cuttings treatment.

5 of 5

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. Lopez-Capel E et al (2016) Biochar properties, 1st edn. Tailor and Francis, Routledge
  2. Sohi S, Lopez-Capel E, Krull E, Bol R (2009) Biochar, climate change and soil: a review to guide future research vol 05. CSIRO

Cited by

Sorted by citations

Related

Authors
Hossain, M. Z., Bahar, M. M., Sarkar, B., Donne, S. W., Ok, Y. S., Palansooriya, K. N., Kirkham, M. B., Chowdhury, S., & Bolan, N.
Affiliations
  • Khulna University (BD)
  • University of Newcastle Australia (AU)
  • Lancaster University (GB)
  • Korea University (KR)
  • Kansas State University (US)
  • Sher-e-Bangla Agricultural University (BD)
Corresponding author
Bolan, Nanthi
ORCID
Venue
Biochar
Publisher
Springer Science and Business Media LLC
Published
2020-09-28
Volume
2
Issue
4
Pages
379-420
ISSN
  • 2524-7867 (ISSN-L)
  • 2524-7972
DOI
10.1007/s42773-020-00065-z
OpenAlex
W3091038929
Cited by
904
References
285
Citations by year
2026: 182 · 2025: 244 · 2024: 215 · 2023: 158 · 2022: 77 · 2021: 28
FWCI
43.49
Type
journal article
Language
en
Open access
Licence
Locations
  • Biochar (publishedVersion)
  • Lancaster EPrints (Lancaster University) (submittedVersion)
  • NOVA (University of Newcastle Australia) (submittedVersion)
Topics
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil Carbon and Nitrogen Dynamics
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Agricultural Science and Fertilization
  • Physical Sciences › Engineering › Biomedical Engineering › Thermochemical Biomass Conversion Processes
Keywords
nutrient dynamics, soil amendment, nutrient use efficiency, nitrogen retention, phosphorus availability, potassium, pyrolysis temperature, soil porosity, surface charge, soil pH, nutrient leaching, soil microbial activity, nutrient uptake, soil aggregate stability

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-10.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-10.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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