The DOI matches its Crossref record; 135 of the 135 references it cites were found in a registry or an index; 5 of the 74 sources its claims cite were checked for support.
Changes in soil organic carbon under biofuel crops
Open accessAbstract
Abstract One potentially significant impact of growing biofuel crops will be the sequestration or release of carbon (C) in soil. Soil organic carbon (SOC) represents an important C sink in the lifecycle C balances of biofuels and strongly influences soil quality. We assembled and analyzed published estimates of SOC change following conversion of natural or agricultural land to biofuel crops of corn with residue harvest, sugarcane, Miscanthus x giganteus , switchgrass, or restored prairie. We estimated SOC losses associated with land conversion and rates of change in SOC over time by regressing net change in SOC relative to a control against age since establishment year. Conversion of uncultivated land to biofuel agriculture resulted in significant SOC losses – an effect that was most pronounced when native land was converted to sugarcane agriculture. Corn residue harvest (at 25–100% removal) consistently resulted in SOC losses averaging 3–8 Mg ha −1 in the top 30 cm, whereas SOC accumulated under all four perennial grasses, with SOC accumulation rates averaging <1 Mg ha −1 yr −1 in the top 30 cm. More intensive harvests led to decreased C gains or increased C losses – an effect that was particularly clear for residue harvest in corn. Direct or indirect conversion of previously uncultivated land for biofuel agriculture will result in SOC losses that counteract the benefits of fossil fuel displacement. Additionally, SOC losses under corn residue harvest imply that its potential to offset C emissions may be overestimated, whereas SOC sequestration under perennial grasses represents an additional benefit that has rarely been accounted for in life cycle analyses of biofuels.
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TL;DR
This synthesis of published soil-carbon measurements finds that clearing uncultivated land for biofuel crops causes soil organic carbon (SOC) losses, corn residue harvest consistently depletes SOC, and perennial grasses tend to build SOC. The authors argue these SOC changes should be included in biofuel life-cycle assessments because they can offset or add to the benefits of displacing fossil fuels.
Key findings
- Across 46 studies and 164 site-treatment combinations, converting native land to biofuel agriculture produced significant SOC losses, with the largest effect when native ecosystems became sugarcane. Corn residue removal at 25–100% consistently lost SOC, averaging 3–8 Mg C ha⁻¹ in the top 30 cm, while all four perennial grass systems accumulated SOC at average rates below 1 Mg C ha⁻¹ yr⁻¹ in the top 30 cm.
- For corn, SOC loss increased with residue removal: about 0.2% per 1% increase in removal, or 0.06–0.09 Mg C ha⁻¹ per 1% increase. A 10-year projection gave roughly 3 Mg C ha⁻¹ lost per 30 cm at 25% removal and about 8 Mg C ha⁻¹ at 100% removal.
- Sugarcane conversion from native land showed an initial loss of about 22% or 20 Mg C ha⁻¹ to a median depth of 15 cm, with model projections up to about 50% near the surface or 34 Mg C ha⁻¹ in the top 30 cm; free-intercept accumulation was 0.29 Mg C ha⁻¹ yr⁻¹ and ANOVA-based accumulation was 0.51 Mg C ha⁻¹ yr⁻¹, with payback within a century but based on only five sites.
- Miscanthus conversion from grassland averaged an 11% or 5.8 Mg C ha⁻¹ loss that was not statistically significant, and free-intercept accumulation averaged 1.0 Mg C ha⁻¹ yr⁻¹ versus 0.14 Mg C ha⁻¹ yr⁻¹ from forced-intercept calculations. Switchgrass percentage SOC increased by 1.8% yr⁻¹ and area-based SOC by about 0.4 Mg C ha⁻¹ yr⁻¹ in ANOVA models or 0.68 Mg C ha⁻¹ yr⁻¹ in forced-intercept models; mixed native sites had intercepts about 68% or 16 Mg C ha⁻¹ above controls and increased by about 1% yr⁻¹ or 0.1 Mg C ha⁻¹ yr⁻¹.
Methods
- The authors searched ISI Web of Science in spring 2008 for studies of SOC change after crop establishment, requiring at least two known field ages including a control, total SOC measured after root removal by dry combustion or dichromate oxidation, and SOC reported by depth or area. They retained 46 studies with 164 site-treatment combinations.
- They estimated SOC accumulation rates and land-conversion effects per site using forced-intercept and free-intercept linear regressions, comparing free intercepts with controls via one-sided t-tests. They also combined sites in ANOVA models (type III SS) for percentage SOC change and net SOC change as functions of age, log depth, biomass removal, and clay, with reduced models for some crops; influential points were removed using Cook’s D.
- Bulk density was used to convert between concentration and area units, calculated with an Adams–Stewart adaptation when missing; clay content was estimated from texture descriptions when not reported.
Limitations
- Stated: the analysis assumes controls are at steady state, so results describe change relative to continued control land use rather than absolute baseline behavior. SOC is spatially variable and hard to match between treatments and controls, and bulk-density shifts can bias area-based SOC changes, likely underestimating both losses and gains; for sugarcane this may mean underestimating both conversion loss and later accumulation.
- Stated: the data come from studies with differing designs and substantial variation in sampling, prior land use, age, depth, management, soil type, and climate, so coefficients should be interpreted cautiously and direct numerical comparisons of accumulation rates among crops are inappropriate; side-by-side trials are needed. Some crops have limited data, such as Miscanthus, or poor representation of certain conditions, such as old corn residue sites and harvested mixed native systems.
- Evident from the text: several key estimates rely on very small samples, including five sites for sugarcane and Miscanthus free-intercept calculations and seven for mixed native free-intercept calculations; switchgrass land-conversion effects could not be reliably assessed because only three sites had multiple ages and none exceeded 3 years.
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Claims the paper makes
42 Own result · 23 No full text of the sources · 22 Own interpretation · 6 Not checked yet · 4 Sources not found · 4 Own method · 3 Supported so far · 2 No basis given · 1 Partly supported · 1 Not supported · accuracy not yet measured
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Cultivation of temperate-zone perennial grasses -Miscanthus, switchgrass, or native mixes -increased SOC by an average of $ 0.1-1 Mg ha À1 yr À1 in the top 30 cm (Figs 234; see also e.g., Potter et al., 1999;Ma et al., 2000;Kahle et al., 2001;Lemus & Lal, 2005;Liebig et al., 2008).”
§ Changes in soil organic carbon under biofuel crops > Discussion
What the sources say
- Not checked — no full text of the sourcecites Potter et al., 1999 source
- Not matchedcites Ma et al., 2000
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Supportedcites Liebig et al., 2008 source
The Results report that switchgrass cultivation increased soil organic carbon across sites at 0–30 cm, with an average accrual rate of 1.1 Mg C ha⁻¹ yr⁻¹—approximately the upper end of the citing sentence’s range. This source supports the switchgrass example; the sentence cites other works for the broader set of grasses. (LLM, conf=0.87)
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In the paper
“In the case of corn, we note that a switch from conventional tillage to no-till concurrent with initiation of residue harvest may offset the negative effects of residue harvest (Clapp et al., 2000;Adler et al., 2007).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Clapp et al., 2000 source
- Supportedcites Adler et al., 2007 source
The Greenhouse-gas sinks section (p. 12) says reduced tillage increases soil organic carbon and that no-till corn rotations had higher soil organic carbon than conventional-tillage rotations. The study removed 50% of corn stover (Crop and biofuel yield, p. 10), so its findings support the hedged suggestion that switching to no-till may offset effects of residue harvest. (LLM, conf=0.84)
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In the paper
“The land conversion loss was roughly 22% or 20 Mg C ha À1 (to a median depth of 15 cm) based on comparison of controls and intercepts (n 5 5, P 5 0.04), but these estimates varied widely depending on ages and depths measured.”
§ Changes in soil organic carbon under biofuel crops > Results
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- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Conversion of grassland to Miscanthus generally resulted in modest C losses followed by SOC accumulation.”
§ Changes in soil organic carbon under biofuel crops > Results
plaindirect- Asserted: passes — The authors put it forward as true.
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- Load-bearing: passes — The paper’s conclusions depend on it.
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- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the free-intercept model indicated that SOC began to rebuild following an initial loss (dSOC a /dt 5 0.29 Mg C ha À1 yr À1 , SE 5 0.31, n 5 5; Fig. 4a).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“Specifically, SOC loss increased by approximately 0.2% for every 1% increase in residue removal (Table B1), or by about 0.06-0.09Mg C ha À1 per 1% increase in residue removal (Table B2).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“Corn residue harvest (at 25-100% removal) consistently resulted in SOC losses averaging 3-8 Mg ha À1 in the top 30 cm, whereas SOC accumulated under all four perennial grasses, with SOC accumulation rates averaging o1 Mg ha À1 yr À1 in the top 30 cm.”
§ Changes in soil organic carbon under biofuel crops > Abstract
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In the paper
“Corn residue harvest (at 25-100% removal) consistently resulted in SOC losses averaging 3-8 Mg ha À1 in the top 30 cm, whereas SOC accumulated under all four perennial grasses, with SOC accumulation rates averaging o1 Mg ha À1 yr À1 in the top 30 cm.”
- Also stated in: § Discussion · boosted
“The harvest of corn residue -even as little as 25%consistently reduced SOC by 3-8 Mg ha À1 in the top 30 cm within the first few years (Figs 2a and 3), with losses increasing linearly with percent residue removal (see also Blanco-Canqui & Lal, 2007).”
§ Changes in soil organic carbon under biofuel crops > Abstract
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- Also stated in: § Discussion · boosted
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In the paper
“Conversion of uncultivated land to biofuel agriculture resulted in significant SOC losses -an effect that was most pronounced when native land was converted to sugarcane agriculture.”
§ Changes in soil organic carbon under biofuel crops > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This loss appears to be most rapid (up to 4.2 Mg C ha À1 yr À1 to 30 cm) immediately following the change in residue management, as indicated by the negative intercepts and nonsignificant effects of age for both SOC c (Fig. 2a, Table B1) and SOC a models (Fig. 3, Table B2)”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“More intensive harvests led to decreased C gains or increased C losses -an effect that was particularly clear for residue harvest in corn.”
§ Changes in soil organic carbon under biofuel crops > Abstract
boosteddirect- Asserted: passes — The authors put it forward as true.
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In the paper
“The rate of loss increased significantly with percentage residue removal in all models (P 0.02; Fig. 3; Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“Free-intercept calculations of SOC accumulation rate averaged 1.0 Mg ha À1 yr À1 (n 5 5) and were greater than both paired forced-intercept calculations (exact Wilcoxon's signed-rank test; SOC c : P 5 0.03, SOC a : P 5 0.30) and the average of all forced-intercept calculations (0.14 Æ 0.35 Mg C ha À1 yr À1 , n 5 8; Fig. 4b).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“In corn, change in management from grain harvest to grain and residue harvest (note that no land conversion occurs in this case) consistently resulted in a loss of SOC, with negative changes for all depth increments of all treatments.”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“We found 46 studies representing 164 site-treatment combinations that matched the criteria outlined above (Tables 1 and A1).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“In our statistical models, SOC increased with age by approximately 1% yr À1 or 0.1 Mg ha À1 yr À1 (P 0.04 for both SOC c and SOC a reduced models; Fig. 3; Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > Results
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A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Conversion of uncultivated land to biofuel agriculture resulted in significant SOC losses -an effect that was most pronounced when native land was converted to sugarcane agriculture.”
§ Changes in soil organic carbon under biofuel crops > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Retention of harvest residues on the fields increased the rate of SOC recovery (P 0.04 for SOC c and SOC a full models; Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“SOC tended to accumulate over time (Figs 234); percentage change in SOC c increased with age by 1.8% yr À1 (Fig. 2d; P 0.04 for reduced and full models; Table B1) and SOC a increased with age at a rate of $ 0.4 Mg ha À1 yr À1 according to the ANOVA models (Fig. 3; P40.3 for reduced and full models; Table B2), or 0.68 Mg ha À1 yr À1 according to the forced-intercept model (SE 5 0.30, n 5 87; Fig. 2”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“The tendency for there to be a land conversion loss followed by SOC accumulation was not statistically significant because of the effects of one site where SOC was lost following the establishment of Miscanthus (Kahle et al., 2001).”
§ Changes in soil organic carbon under biofuel crops > Results
What the sources say
- Not checked — no full text of the sourcecites Kahle et al., 2001 source
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In the paper
“Conversion of native ecosystems (forest or grassland) to sugarcane resulted in a large initial loss of SOC followed by recovery.”
§ Changes in soil organic carbon under biofuel crops > Results
plaindirect- Asserted: passes — The authors put it forward as true.
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- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Specifically, SOC loss increased by approximately 0.2% for every 1% increase in residue removal (Table B1), or by about 0.06-0.09Mg C ha À1 per 1% increase in residue removal (Table B2).”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“SOC tended to accumulate over time (Figs 234); percentage change in SOC c increased with age by 1.8% yr À1 (Fig. 2d; P 0.04 for reduced and full models; Table B1) and SOC a increased with age at a rate of $ 0.4 Mg ha À1 yr À1 according to the ANOVA models (Fig. 3; P40.3 for reduced and full models; Table B2), or 0.68 Mg ha À1 yr À1 according to the forced-intercept model (SE 5 0.30, n 5 87; Fig. 2”
§ Changes in soil organic carbon under biofuel crops > Results
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In the paper
“Corn residue harvest (at 25-100% removal) consistently resulted in SOC losses averaging 3-8 Mg ha À1 in the top 30 cm, whereas SOC accumulated under all four perennial grasses, with SOC accumulation rates averaging o1 Mg ha À1 yr À1 in the top 30 cm.”
§ Changes in soil organic carbon under biofuel crops > Abstract
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- Load-bearing: passes — The paper’s conclusions depend on it.
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In the paper
“Losses were proportionally greater at shallow depths (Fig. 2a), reinforcing the conclusion that the loss is caused more by reduced residue inputs than by reduced belowground C inputs.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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In the paper
“In the case of native grasslands, fields that were burned or grazed tended to have lower SOC than those that were not burned (Tables B1and B2); however, the effects of grazing on SOC are mixed (Holt, 1997;Frank et al., 1995;De Deyn et al., 2008;Ingram et al., 2008).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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In the paper
“In our analysis, clay content tended to reduce the net change in SOC, moderating both losses in corn and gains in perennial grasses (Tables B1-2).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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In the paper
“For switchgrass, harvested fields tended to accumulate SOC less rapidly than fields that have not been harvested, but this effect was partially offset by higher intercepts for harvested fields (Tables B1 and 2), which is more likely a statistical artifact than a biological reality.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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In the paper
“In the case of sugarcane, fields burned before harvest have lower SOC than unburned fields where the harvest residue is retained on the fields (Blair et al., 1998;Graham et al., 2002), and our models likewise revealed that retention of harvest residue resulted in faster SOC accumulation (Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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plaincorrelational- Asserted: passes — The authors put it forward as true.
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In the paper
“In the case of sugarcane, fields burned before harvest have lower SOC than unburned fields where the harvest residue is retained on the fields (Blair et al., 1998;Graham et al., 2002), and our models likewise revealed that retention of harvest residue resulted in faster SOC accumulation (Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
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In the paper
“The effect of biomass removal is particularly pronounced in the case of corn residue harvest; our results (Fig. 3, Tables B1 and B2) and previous research (Larson et al., 1972;Mann et al., 2002;Blanco-Canqui & Lal, 2007) demonstrate that SOC loss consistently increases with percentage residue harvest.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
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In the paper
“Residue removal (%) À0.226 (0.065) 1 783 783 12.1 0.001 À0.18 (0.03) 1 2233 2233 29.3 o0.0001”
§ Changes in soil organic carbon under biofuel crops > Additional information
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In the paper
“Removal of corn residue is detrimental with regard to SOC; our analysis indicates that SOC is lost under any level of residue removal (Fig. 3; Mann et al., 2002;Blanco-Canqui & Lal, 2007).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Clay (%) 0.33 (0.10) 1 683 683 10.5 0.002”
§ Changes in soil organic carbon under biofuel crops > Additional information
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Additionally, SOC losses under corn residue harvest imply that its potential to offset C emissions may be overestimated, whereas SOC sequestration under perennial grasses represents an additional benefit that has rarely been accounted for in life cycle analyses of biofuels.”
§ Changes in soil organic carbon under biofuel crops > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Additionally, SOC losses under corn residue harvest imply that its potential to offset C emissions may be overestimated, whereas SOC sequestration under perennial grasses represents an additional benefit that has rarely been accounted for in life cycle analyses of biofuels.”
§ Changes in soil organic carbon under biofuel crops > Abstract
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“These losses should be attributed more to the disturbance of native or restored ecosystems, which consistently reduces SOC (Davidson & Ackerman, 1993;Guo & Gifford, 2002;Murty et al., 2002;West et al., 2004;Zinn et al., 2005), than to the cultivation of any specific crop.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These changes can be explained in light of three principles that govern the C balance of biofuel crops, which we discuss in detail below: (1) conversion of uncultivated land to biofuel crops entails a soil C loss; (2) crops differ in their ability to sequester SOC, with perennial grasses outperforming corn; and (3) there appears to be a tradeoff between biomass harvest and SOC sequestration.”
§ Changes in soil organic carbon under biofuel crops > Discussion
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Conversely, SOC accumulates upon conversion of cultivated land to secondary forest, grassland, or pasture (Potter et al., 1999;Knops & Tilman, 2000;Guo & Gifford, 2002;West et al., 2004;Grandy & Robertson, 2007).”
§ Changes in soil organic carbon under biofuel crops > Introduction
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The land conversion loss appears to be repaid within a century (Figs 3 and 4a); however, this SOC payback time is difficult to quantify given the limited sample size (n 5 5).”
§ Changes in soil organic carbon under biofuel crops > Results
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Direct or indirect conversion of previously uncultivated land for biofuel agriculture will result in SOC losses that counteract the benefits of fossil fuel displacement.”
§ Changes in soil organic carbon under biofuel crops > Abstract
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“This result is to be expected based on the principle that SOC equilibrates at higher levels with higher organic matter inputs (Mann et al., 2002).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Mann et al., 2002 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“As roots and rhizomes are a primary source of C to the soil in biofuel crops (Garten & Wullschleger, 2000;Wilhelm et al., 2004;Lemus & Lal, 2005), belowground allocation of C stands to play a critical role in driving changes in SOC.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“As changes in SOC of controls would bias estimates of rate or land conversion effect, our findings are most properly interpreted as describing the change in SOC relative to what would occur if the land remained under the same land use as the control.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- The authors state this as an assumption: Controls are at steady-state with respect to SOC.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“As roots and rhizomes are a primary source of C to the soil in biofuel crops (Garten & Wullschleger, 2000;Wilhelm et al., 2004;Lemus & Lal, 2005), belowground allocation of C stands to play a critical role in driving changes in SOC.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Finally, data sets for some crops are limited in size (e.g., Miscanthus) or representation of certain variables (e.g., old fields with corn residue harvest, harvested mixed native systems; Table 1), which reduces the potential to detect changes and accurately estimate effects.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Conversely, reduced tillage results in soil C sequestration (e.g., West & Post, 2002;Bernacchi et al., 2005;Grandy & Robertson, 2007), and SOC accumulation under perennial grasses grown on former cropland may be partially attributable to the cessation of tillage.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“This suggests that SOC accumulation may tend to increase with precipitation (Paul et al., 2002).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Paul et al., 2002 source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“As corn productivity is within the range of the perennial grasses, differences in productivity cannot explain the SOC loss in corn in contrast to the gain by perennial grasses.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the observed contrast between SOC losses under corn with residue harvest and gains under perennial grasses cannot be explained as an effect of tillage, as 13 of the 15 corn treatments were under no-till practices (Table A1).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Additionally, changes in bulk density may bias calculations of change in SOC a by changing the total mass of soil within the depth increment.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Ellert et al., 2000
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We emphasize that failure to consider land conversion losses separately from crop-induced SOC changes can severely bias estimates of crop performance (e.g., Figs 1 and 4).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“However, the differential responses of productivity and decomposition to temperature (Allen et al., 2005) imply that the magnitude and direction of changes in SOC may vary along temperature gradients.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Allen et al., 2005 source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Conversely, reduced tillage results in soil C sequestration (e.g., West & Post, 2002;Bernacchi et al., 2005;Grandy & Robertson, 2007), and SOC accumulation under perennial grasses grown on former cropland may be partially attributable to the cessation of tillage.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Losses were proportionally greater at shallow depths (Fig. 2a), reinforcing the conclusion that the loss is caused more by reduced residue inputs than by reduced belowground C inputs.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
None of the sources cited for this claim have been checked yet.
In the paper
“Fertilization -which boosts productivity but decreases belowground C allocation (Ma et al., 2001;Bonifas et al., 2005) and may increase soil respiration (Bauhus & Khanna, 1994) -consistently increased SOC gains or decrease SOC losses in perennial grasses, although its effects often were not significant (Ma et al., 2000;Graham et al., 2002;Thomason et al., 2005;Lee et al., 2007).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We note thatdue to their recent inception -there is a lack of information about long-term soil C patterns under switchgrass and Miscanthus crops (Table 1) and that cultivation practices are actively being modified.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Whereas growing perennial grasses on C-depleted soil (e.g., agricultural land) provides an immediate SOC-sequestration benefit, replacing uncultivated land with biofuel crops -either directly or indirectly (Gurgel et al., 2007;Searchinger et al., 2008) -may not provide any SOC sequestration benefits for decades or even centuries.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
None of the sources cited for this claim have been checked yet.
In the paper
“SOC sequestration by the temperate perennial grasses (i.e., Miscanthus, switchgrass, and North American native mixtures), as observed here and else-where (e.g., Potter et al., 1999;Ma et al., 2000;Kahle et al., 2001;Lemus & Lal, 2005;Liebig et al., 2005Liebig et al., , 2008)), would augment the benefits of fossil fuel displacement.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Clearing and tillage of natural ecosystems or pastures for the purpose of biofuel cultivation incurs a SOC loss that will offset SOC sequestration by the crop until the new C accumulation reaches a level that restores the initial loss following crop planting (Fig. 1).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
In the paper
“Land conversion losses will play a major role in determining the C balance of biofuel crops (Fargione et al., 2008).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Fargione et al., 2008 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Whereas growing perennial grasses on C-depleted soil (e.g., agricultural land) provides an immediate SOC-sequestration benefit, replacing uncultivated land with biofuel crops -either directly or indirectly (Gurgel et al., 2007;Searchinger et al., 2008) -may not provide any SOC sequestration benefits for decades or even centuries.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- It may state two separate claims as one. 40
- Probably not a substantial claim. 9
At least one cited source doesn’t support this claim or points to a different paper, and none confirmed it — see the verdicts below.
In the paper
“SOC losses of the magnitude observed here have not been included in life cycle analyses of biofuel production from corn residue (Sheehan et al., 2003;Powers, 2005;Spatari et al., 2005;Adler et al., 2007), which implies that the sustainability and net benefits of biofuel production from residue have been overestimated.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Disputedcites Sheehan et al., 2003 sourceExperimental — accuracy not yet measured
Split into 2 atoms — 1 confirmed, 0 partially supported, 1 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.
Checked by a reasoning model — may be wrong.
- Not checked yetcites Powers, 2005 source
Checked before — its earlier verdict is held back until a new check runs.
- Not checked — no full text of the sourcecites Spatari et al., 2005 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Disputed
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“SOC sequestration is an important component in the life cycle of biofuel production (Ney & Schnoor, 2002;Adler et al., 2007) and may be key in determining the greenhouse gas (GHG) reduction potential of biofuels relative to fossil fuels.”
§ Changes in soil organic carbon under biofuel crops > Introduction
What the sources say
- Not matchedcites Ney & Schnoor, 2002
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Supportedcites Adler et al., 2007 source
The Greenhouse-gas sinks section (p. 6) identifies system carbon, including SOC, as the second-largest GHG sink. The Net greenhouse-gas flux section (p. 8) reports smaller GHG reductions when soil carbon sequestration is excluded from the long-term scenario, supporting its importance to the life-cycle comparison with fossil fuels. The paper also notes that displaced fossil fuel is the dominant factor and soil sequestration is a short-term contribution (Global-warming potential, pp. 14–15). (LLM, conf=0.91)
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Changes in SOC will significantly affect efforts to mitigate GHG emissions (Ney & Schnoor, 2002;Adler et al., 2007) and impact a host of other ecosystem services (Lal, 2004).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Ney & Schnoor, 2002
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Supportedcites Adler et al., 2007 source
Adler et al. support the GHG-mitigation clause: in “Greenhouse-gas sinks” (p. 6), changes in system carbon, including SOC, are the second-largest GHG sink assessed. The “Global-warming potential” section (p. 14) also distinguishes near-term results from a long-term scenario in which soil carbon no longer increases. The separate ecosystem-services clause is cited to Lal (2004), not Adler et al. (LLM, conf=0.91)
- Not checked — no full text of the sourcecites Lal, 2004 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The land conversion effect was positive (Figs 3 and 4d); intercepts were $ 68% or 16 Mg C ha À1 greater than the controls; and the ratios of the intercept to the control was significantly 41 (one-sample t-test; P 5 0.02).”
§ Changes in soil organic carbon under biofuel crops > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“More intensive harvests led to decreased C gains or increased C losses -an effect that was particularly clear for residue harvest in corn.”
§ Changes in soil organic carbon under biofuel crops > Abstract
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Switchgrass studied in the literature typically was planted on cropland, fallow land, or grassland (Table 1).”
§ Changes in soil organic carbon under biofuel crops > Results
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The average land conversion loss was approximately 11% or 5.8 Mg C ha À1 (n 5 5; Fig. 4b); however, the ratio of the intercept to the control was not significantly o1 (P 5 0.16), indicating that this loss was not significant.”
§ Changes in soil organic carbon under biofuel crops > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- The authors state this as an assumption: The free-intercept model's intercept difference from the control estimates the land conversion effect.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“As a result of this initial loss, the forced-intercept model gave negative rates of change in SOC a (À0.67 Mg C ha À1 yr À1 , SE 5 0.36, n 5 18; Fig. 4a), indicating a net loss of SOC for the majority of sites (median age 5 35; Table 1).”
§ Changes in soil organic carbon under biofuel crops > Results
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“When biomass was harvested, SOC accumulation tended to be less rapid (SOC c : P 5 0.05, SOC a : P 5 0.66; Tables B1 and B2), but this was partially offset by higher intercepts (SOC c : P 5 0.07; SOC a : P 5 0.72; Tables B1 and B2).”
§ Changes in soil organic carbon under biofuel crops > Results
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Overall, our statistical model (Table B2) predicted that 10 years of maize biomass removal resulted in losses of $ 3 Mg C ha À1 per 30 cm at 25% residue removal and $ 8 Mg C ha À1 per 30 cm at 100% residue removal (Fig. 3).”
§ Changes in soil organic carbon under biofuel crops > Results
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Likewise, the ANOVA models indicated SOC accumulation rates of about 0.33% yr À1 (SOC c reduced model: P 5 0.10; Fig. 2b) or 0.51 Mg C ha À1 yr À1 (SOC a reduced model: P 5 0.006; Fig. 3).”
§ Changes in soil organic carbon under biofuel crops > Results
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“SOC tended to accumulate over time (Figs 234); percentage change in SOC c increased with age by 1.8% yr À1 (Fig. 2d; P 0.04 for reduced and full models; Table B1) and SOC a increased with age at a rate of $ 0.4 Mg ha À1 yr À1 according to the ANOVA models (Fig. 3; P40.3 for reduced and full models; Table B2), or 0.68 Mg ha À1 yr À1 according to the forced-intercept model (SE 5 0.30, n 5 87; Fig. 2”
§ Changes in soil organic carbon under biofuel crops > Results
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Tillage releases SOC and was probably largely responsible for the observed land conversion losses (Fig. 4).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Harvesting biomass appears to reduce SOC or to slow its rate of accumulation.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Age  residue removal 0.006 (0.008) 1 39.1 39.1 0.6 0.44”
§ Changes in soil organic carbon under biofuel crops > Additional information
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Age (years) 0.36 (0.84) 1 11.9 11.9 0.2 0.67 0.35 (0.41) 1 54.0 54.0 0.7 0.40”
§ Changes in soil organic carbon under biofuel crops > Additional information
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Log(depth) (cm) 7.86 (3.24) 1 384 384 5.9 0.02 6.25 (1.48) 1 1367.21367.2 17.9 o0.0001”
§ Changes in soil organic carbon under biofuel crops > Additional information
plaincorrelational- Asserted: passes — The authors put it forward as true.
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- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Age  log(depth) À0.12 (0.39) 1 6.5 6.5 0.1 0.44”
§ Changes in soil organic carbon under biofuel crops > Additional information
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Whereas soil C is depleted under corn residue harvest, it accumulates under cultivation of perennial grasses.”
§ Changes in soil organic carbon under biofuel crops > Discussion
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“This forced-intercept model assumes a linear change in SOC through time, and therefore will underestimate rates of SOC change if there is a land conversion loss (Fig. 1).”
§ Changes in soil organic carbon under biofuel crops > Methods
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Conversion of native ecosystems to crops causes substantial losses of SOC (averaging about 30%), which is most rapid immediately following land conversion (Davidson & Ackerman, 1993;Guo & Gifford, 2002;Murty et al., 2002;West et al., 2004;Zinn et al., 2005;De Deyn et al., 2008;David et al., in press), probably stabilizing within the first several decades of cultivation (David et al., in press).”
§ Changes in soil organic carbon under biofuel crops > Introduction
What the sources say
hedgeddirect- Asserted: passes — The authors put it forward as true.
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A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Because grasslands tend to have high SOC, conversion of native ecosystems to pasture generally does not release SOC, and sometimes results in modest SOC sequestration (Fisher et al., 1994;Guo & Gifford, 2002;Murty et al., 2002;Osher et al., 2003;Zinn et al., 2005).”
§ Changes in soil organic carbon under biofuel crops > Introduction
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Land conversion effect could not be reliably assessed, as only three sites had data for more than one age, and none of these exceeded 3 years in age (Table 1).”
§ Changes in soil organic carbon under biofuel crops > Results
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
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It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“This may be attributed to the effects of tillage, which stimulates a release of C from soil (e.g., Reicosky et al., 1997) or to a deficiency of organic inputs relative to decomposition early in crop establishment (Paul et al., 2002).”
§ Changes in soil organic carbon under biofuel crops > Discussion
What the sources say
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
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It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“The biofuel crops considered here match this pattern; observed root : shoot ratios are $0.3 for fertilized corn (Bonifas et al., 2005), $0.15 for sugarcane in nonfield conditions (Ebrahim et al., 1998;Smith et al., 2005), $1 for Miscanthus (Neukirchen et al., 1999), 1.8-6.1 for switchgrass (Ma et al., 2001), and 2-8 for North American prairies (Wilson, 1993;Ojima et al., 1994).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaincorrelational- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“For sugarcane, this would imply underestimates of both the land conversion loss and the rate of SOC a accumulation.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgeddirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“As the rate of soil organic matter mineralization generally responds positively to increased soil moisture but negatively to decreased temperature (Leiro ´s et al., 1999), it is not clear how differences in cover among crops affect SOC losses.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Leiro ´s et al., 1999
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
In the paper
“As a result, change in SOC a is artificially high (tending toward gains) in situations where bulk density has increased and artificially low (tending toward losses) in situations where it has decreased (Ellert et al., 2000).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Ellert et al., 2000
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaindirect- Asserted: passes — The authors put it forward as true.
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- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“As a result, estimated coefficients should be interpreted with caution; for example, direct numerical comparisons of SOC accumulation rates among crop types would be inappropriate; rather, side-by-side comparisons of perennial grasses will be necessary to rank their SOC accumulation rates.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: fails — It may be too vague to check against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. It may be too vague to check against evidence. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“It is also noteworthy that our data comes from multiple studies with differing research designs, such that there is substantial within-and between-crop variation in factors such as number of samples, previous land uses, ages and depths sampled, management practices, soil types, and climate (Tables 1, A1).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“Both production and decomposition increase with precipitation, but the relative advantage appears to switch from decomposition at low precipitation to production at high precipitation (Austin, 2002).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Austin, 2002 source
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“SOC is spatially variable, making it difficult to match treatments with controls (Ellert et al., 2000) and to detect change in SOC (Garten & Wullschleger, 1999) -a problem that increases the variability within our data set.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Ellert et al., 2000
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not checked — no full text of the sourcecites Garten & Wullschleger, 1999 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
In the paper
“For sugarcane fields converted from native forest in Hawaii, sites with rainfalls of 2500 mm yr À1 and 4000 mm yr À1 had lost similar amounts of forest C, but sites receiving more rainfall had accumulated cane-derived C at a higher rate (Osher et al., 2003).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Osher et al., 2003 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Harvesting may also affect the depth distribution of new C inputs; the proportionally greater C accumulation at shallow depths in prairie (Fig. 2e) -which contrasts with the depth-independence of percentage change in C concentration of Miscanthus and switchgrass (Fig. 2c and d)may be attributable to the fact that prairie sites were not harvested (Table 1).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Additionally, decomposition is influenced by litter quality; high lignin content of litter extends the residence time of C in the soil (McClaugherty et al., 1985).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites McClaugherty et al., 1985 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Thus, the temperate perennial grasses introduce far more C to the soil than corn, potentially explaining the difference between corn and these grasses.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Soil type affects both the input of C to the soil by affecting plant productivity (Epstein et al., 1997) and the decomposition of organic matter (Sorensen, 1981;Paul, 1984;Jobba ´gy & Jackson, 2000).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Development of corn to maximize energy allocation to grain may reduce the complexity of tissues that eventually become litter (Gifford et al., 1984), making its tissues readily degradable.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Gifford et al., 1984 source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Both productivity and decomposition increase with mean annual temperature such that SOC turnover should be fastest in warm climates (Schimel et al., 1994) and any proportional difference between the input of new organic material and decomposition of the old will tend to translate into faster rates of SOC loss or gain (Post & Kwon, 2000;Paul et al., 2002).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Schimel et al., 1994 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“Allocation of C to root biomass is dramatically lower in traditional annual crops than in temperate grasslands, with globally averaged root : shoot ratios of 0.1 and 3.7, respectively (Jackson et al., 1996).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Jackson et al., 1996 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In switchgrass crops planted across a temperature gradient in North America, SOC turnover rate, the proportion of switchgrassderived SOC, and net change in SOC all increased with temperature (Garten & Wullschleger, 2000).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Garten & Wullschleger, 2000 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“For switchgrass, harvested fields tended to accumulate SOC less rapidly than fields that have not been harvested, but this effect was partially offset by higher intercepts for harvested fields (Tables B1 and 2), which is more likely a statistical artifact than a biological reality.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“The protective cover of canopies or litter layers affects the microclimate, reducing evaporation rates and dampening temperature fluctuations (Wilhelm et al., 2004).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not matchedcites Wilhelm et al., 2004
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Changes in SOC are not typically included in sugarcane life cycle analyses (Mohee & Beeharry, 1999;Beeharry, 2001;Botha & von Blottnitz, 2006), but could have a substantial impact on their outcomes.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Advancements in harvest efficiency, reduced allocation to roots through genetic modifications or changes in cultivation practices (e.g., fertilization), or genetic modifications that yield more decomposable plants (Ragauskas et al., 2006) could reduce -or possibly even reverse -SOC sequestration.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
What the sources say
- Not checked — no full text of the sourcecites Ragauskas et al., 2006 source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In such cases, the soil C sequestration benefits would augment the GHG reduction associated with fossil fuel displacement.”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper may give no reason why it holds.
The paper relies on this without support.
Many studies have quantified changes in SOC under potential biofuel crops, but results are variable and have yet to be synthesized into a coherent picture.
“While many studies have quantified changes in SOC under potential biofuel crops, results are variable and have yet to be synthesized into a coherent picture.”
The authors state this as an assumption.
The free-intercept model's intercept difference from the control estimates the land conversion effect.
“This model uses a regression of net change in SOC relative to the control as a function of time to calculate a SOC accumulation rate and an intercept, which differs from the control when there is a land conversion effect.”
The authors state this as an assumption.
Controls are at steady-state with respect to SOC.
“First, our analysis assumes that controls are at steady-state with respect to SOC (Fig. 1), which may not be true of some controls (e.g., fallows, young grasslands).”
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?
The source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“According to studies conducted over the last 15 years, advanced lignocellulosic bioenergy crops like miscanthus have the potential to cut GHG emissions more effectively than corn (Anderson- Teixeira et al., 2009; Davis et al., 2012; Hudiburg etal.,2015; Von Hellfeld etal.,2022).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson- Teixeira et al., 2009
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“When grasslands are cleared and tilled for the purpose of cultivating miscanthus, it results in C losses until new C accumulation reaches a level that is sufficient to restore the initial loss that occurred during crop planting (Anderson- Teixeira etal.,2009; Jones etal.,2016).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson-Teixeira et al., 2009
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“Conversion from annual cropland to a perennial crop such as miscanthus is expected to increase C sequestration due to greater belowground allocation of C compared to annual crops (Anderson- Teixeira et al., 2009; Davis etal.,2010).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson-Teixeira et al., 2009
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“The net change of soil surface 30 cm soil organic carbon in 15 years is predicted to be 6.49 Mg ha−1, significantly higher than that of other crops.”
From Effects of Biofuel Crop Switchgrass (Panicum virgatum) Cultivation on Soil Carbon Sequestration and Greenhouse Gas Emissions: A Review (2022) · cites this paper as [19]
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“In general, annual cropland conversion to perennial crops results in increased SOC stocks but SOC decreased if perennial crops or grasslands are converted to annual crops (Anderson-Teixeira et al., 2009;Poeplau et al., 2011).”
From Land‐use change to bioenergy production in Europe: implications for the greenhouse gas balance and soil carbon (2012) · cites this paper as Anderson-Teixeira et al., 2009
Experimental — accuracy not yet measured
The cited source says what the claim attributes to it.
In the citing paper
“Well- managed cellulosic feedstocks, like miscanthus, can remove CO2 from the atmosphere which may then be stored in soils even after the plant biomass is harvested (Anderson et al., 2011; Anderson- Teixeira et al., 2009; Davis etal.,2009).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson-Teixeira et al., 2009
The cited source says what the claim attributes to it.
In the citing paper
“The sequestration rates obtained from this study corroborate the findings of prior studies (e.g., Anderson- Teixeira et al., 2009; Mishra et al., 2013).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson-Teixeira et al., 2009
The cited source says what the claim attributes to it.
In the citing paper
“The diverse site conditions, geographical locations, soil types, management strategies, and prior land use histories may provide an explanation for the range in C accumulation (Adjuik & Davis, 2022; Anderson- Teixeira et al., 2009; Davis etal.,2013; Zimmermann etal.,2013).”
From Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio (2024) · cites this paper as Anderson-Teixeira et al., 2009
In the citing paper
“Its impacts on carbon stocks (e.g., vegetation, soil) can be so large [75,76] that biofuels' GHG benefits are offset from a life-cycle perspective [9,70].”
From Biomass and biofuels in China: Toward bioenergy resource potentials and their impacts on the environment (2018) · cites this paper as [76]
In the citing paper
“There are very few data for Miscanthus [62, 65, 150], switchgrass [178, 179], willow [143, 180] or poplar [22] available.”
From Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out? (2015) · cites this paper as [178]
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.
Rated major: it would touch a result — a value a result rests on, reported and recomputed p-values on opposite sides of the significance level, two passages that conflict with no sign which is right, or a cited work retracted before this paper was published.
In the paper
§ Changes in soil organic carbon under biofuel crops > Results
“The effects of clay content were opposite in the SOC c (negative effect; P 5 0.008) and SOC a models (positive effect; P 5 0.0003).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
“Clay (%) À0.24 (0.07) 1 983.0 983.0 13.6 0.0003”
Rated major: it would touch a result — a value a result rests on, reported and recomputed p-values on opposite sides of the significance level, two passages that conflict with no sign which is right, or a cited work retracted before this paper was published.
In the paper
§ Changes in soil organic carbon under biofuel crops > Results
“These were not managed as biofuel crops; none of the fields were harvested and only 5% were fertilized (Table 1).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
“Annual harvest À14.0 (32.7)”
Rated major: it would touch a result — a value a result rests on, reported and recomputed p-values on opposite sides of the significance level, two passages that conflict with no sign which is right, or a cited work retracted before this paper was published.
In the paper
§ Changes in soil organic carbon under biofuel crops > Results
“Change in SOC a increased with sampling depth (reduced model; P 5 0.002).”
§ Changes in soil organic carbon under biofuel crops > 80 K . J . A N D E R S O N -T E I X E I R A e t a l.
“Log (depth) (cm) 2.91 (1.20) 1 425.8 425.8 5.9 0.02 0.92 (0.76) 1 119.0 1.5 0.23”
Citations
Cites
Soil Carbon Sequestration Impacts on Global Climate Change and Food Security
Lal, R. (2004) · Science · doi:10.1126/science.1097396 · Cited by 8,376
Temperature sensitivity of soil carbon decomposition and feedbacks to climate change
Davidson, E. A., & Janssens, I. A. (2006) · Nature · doi:10.1038/nature04514 · Cited by 6,919
Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change
Searchinger, T., Heimlich, R., Houghton, R. A., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D., & Yu, T.-H. (2008) · Science · doi:10.1126/science.1151861 · Cited by 4,888 · cited 2×
“…C-depleted soil (e.g., agricultural land) provides an immediate SOC-sequestration benefit, replacing uncultivated land with biofuel crops – either directly or indirectly (Gurgel et al., 2007; Searchinger et al., 2008) – may not provide any SOC sequestration benefits for decades or even centuries.”
Soil carbon stocks and land use change: a meta analysis
Guo, L. B., & Gifford, R. M. (2002) · Global Change Biology · doi:10.1046/j.1354-1013.2002.00486.x · Cited by 3,972
Land Clearing and the Biofuel Carbon Debt
Fargione, J., Hill, J., Tilman, D., Polasky, S., & Hawthorne, P. (2008) · Science · doi:10.1126/science.1152747 · Cited by 3,902
A global analysis of root distributions for terrestrial biomes
Jackson, R. B., Canadell, J., Ehleringer, J. R., Mooney, H. A., Sala, O. E., & Schulze, E. D. (1996) · Oecologia · doi:10.1007/bf00333714 · Cited by 3,071
Climate–Carbon Cycle Feedback Analysis: Results from the C4MIP Model Intercomparison
Friedlingstein, P., Cox, P., Betts, R., Bopp, L., von Bloh, W., Brovkin, V., Cadule, P., Doney, S., Eby, M., Fung, I., et al. (2006) · Journal of Climate · doi:10.1175/jcli3800.1 · Cited by 2,902
Cornwell, W. K., Cornelissen, J. H. C., Amatangelo, K., Dorrepaal, E., Eviner, V. T., Godoy, O., Hobbie, S. E., Hoorens, B., Kurokawa, H., Pérez‐Harguindeguy, N., et al. (2008) · Ecology Letters · doi:10.1111/j.1461-0248.2008.01219.x · Cited by 2,855
Soil carbon sequestration and land‐use change: processes and potential
Post, W. M., & Kwon, K. C. (2000) · Global Change Biology · doi:10.1046/j.1365-2486.2000.00308.x · Cited by 2,602
Soil Organic Carbon Sequestration Rates by Tillage and Crop Rotation: A Global Data Analysis
West, T. O., & Post, W. M. (2002) · Soil Science Society of America Journal · doi:10.2136/sssaj2002.1930 · Cited by 2,215 · cited 1×
“Conversely, reduced tillage results in soil C sequestration (e.g., West & Post, 2002; Bernacchi et al., 2005; Grandy & Robertson, 2007), and SOC accumulation under perennial grasses grown on former cropland may be partially attributable to the cessation of tillage.”
Background
Research works printed but not linked: 2
- Renewable Fuels Agency, 2008, The Gallagher Review of the Indirect Effects of Biofuels Production
- 10.1021/es048293 · DOI
Cited by
Sorted by citations
Beneficial biofuels—the food, energy, and environment trilemma
Tilman, D., Socolow, R., Foley, J. A., Hill, J., Larson, E., Lynd, L., Pacala, S., Reilly, J., Searchinger, T., Somerville, C., et al. (2009) · Science · doi:10.1126/science.1177970 · Cited by 1,596
Kell, D. B. (2011) · Annals of Botany · doi:10.1093/aob/mcr175 · Cited by 439
“…Dondini et al., 2009a, b; Hillier et al., 2009), Panicum virgatum (switchgrass) (Ma et al., 2000, 2001; Liebig et al., 2005; Al-Kaisi and Grote, 2007; Anderson-Teixeira et al., 2009; Collins et al., 2010) and vetiver (Chrysopogon zizanoides L.) (Grimshaw, 2008; Lavania and Lavania, 2009) grasses,…”
Don, A., Osborne, B., Hastings, A., Skiba, U., Carter, M. S., Drewer, J., Flessa, H., Freibauer, A., Hyvönen, N., Jones, M. B., et al. (2012) · GCB Bioenergy · doi:10.1111/j.1757-1707.2011.01116.x · Cited by 363
Khangura, R. K., Ferris, D., Wagg, C., & Bowyer, J. (2023) · Sustainability · doi:10.3390/su15032338 · Cited by 475
Wiesmeier, M., Spörlein, P., Geuß, U., Hangen, E., Haug, S., Reischl, A., Schilling, B., Lützow, M. V., & Kögel‐Knabner, I. (2012) · Global Change Biology · doi:10.1111/j.1365-2486.2012.02699.x · Cited by 346
Metadata
- Authors
- ANDERSON‐TEIXEIRA, K. J., DAVIS, S. C., MASTERS, M. D., & DELUCIA, E. H.
- Affiliations
- University of Illinois Urbana-Champaign (US)
- Venue
- GCB Bioenergy
- Publisher
- Wiley
- Published
- 2009-02
- Volume
- 1
- Issue
- 1
- Pages
- 75-96
- ISSN
- 1757-1693 (ISSN-L)
- 1757-1707
- OpenAlex
- W2000786281
- Semantic Scholar
- b7122b4a1607d7e200d13acb4c21f0e0b2d26e24
- Cited by
- 391
- References
- 131
- Citations by year
- 2026: 6 · 2025: 8 · 2024: 10 · 2023: 15 · 2022: 10 · 2021: 24 · 2020: 24 · 2019: 22 · 2018: 25 · 2017: 39 · 2016: 28 · 2015: 34 · 2014: 34 · 2013: 39 · 2012: 37
- FWCI
- 40.77
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- GCB Bioenergy (publishedVersion)
- Funders
- Energy Biosciences Institute
- University of Illinois at Urbana-Champaign
- Topics
- Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil Carbon and Nitrogen Dynamics
- Life Sciences › Agricultural and Biological Sciences › Agronomy and Crop Science › Bioenergy crop production and management
- Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil erosion and sediment transport
- Keywords
- soil organic carbon, energy crops, land conversion, carbon sequestration, sugarcane, Miscanthus × giganteus, switchgrass, restored prairie, perennial grasses, carbon cycle, life cycle assessment
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.
A language model drew the claims from the paper on 2026-10-11, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-11 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Cited sources are checked with a language model’s help (gpt-6-sol).
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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