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Earliest land plants created modern levels of atmospheric oxygen
Open accessAbstract
Significance: The rise of atmospheric oxygen over Earth’s history has received much recent interdisciplinary attention. However, the puzzle of when and how atmospheric oxygen reached modern levels remains unresolved. Many recent studies have argued for a major oxygenation event—of uncertain cause—in the Neoproterozoic Era >541 Ma, enabling the rise of animals. Previous modelling work has predicted a late Paleozoic oxygen rise (<380 Ma) due to the rise of forests. Here we show that neither scenario is correct. Instead, the earliest plants, which colonized the land from 470 Ma onward, first increased atmospheric oxygen to present levels by 400 Ma, and this instigated fire-mediated feedbacks that have stabilized high oxygen levels ever since, shaping subsequent evolution.
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TL;DR
The paper argues that the earliest land plants, colonizing from ∼470 Ma, drove a mid-Paleozoic oxygenation event by increasing organic carbon burial, raising atmospheric O₂ to present levels by 420–400 Ma. It uses a revised COPSE biogeochemical model plus a trait-based cryptogamic vegetation model and bryophyte C/P data to reproduce a sustained +2‰ δ¹³C shift and O₂ rise consistent with charcoal and redox proxies.
Key findings
- Earliest nonvascular plants colonized land from ∼470–445 Ma; the model reproduces a sustained +2‰ δ¹³C increase by ∼445 Ma and an O₂ rise to present levels by 420–400 Ma, consistent with fossil charcoal indicating O₂ >15–17% by 420–400 Ma and Mo isotope evidence for deep-ocean oxygenation at 435–392 Ma.
- A trait-based ecophysiological model predicts cryptogamic vegetation cover at 445 Ma (CO₂ = 8 PAL, O₂ = 0.6 PAL) could achieve global NPP = 18.7 GtC·y⁻¹, ∼30% of today; COPSE with stronger Late Ordovician colonization predicts 30–40% of today’s NPP.
- Bryophyte C/P literature ranges from 800 to 4,300 (mean ∼1,900); assuming C/P = 2,000 vs 1,000 increases modeled organic carbon burial by ∼50% vs ∼25%, δ¹³C by +1.1‰ vs +0.5‰, and O₂ by +0.27 vs +0.11 PAL.
- Reproducing the observed +2‰ δ¹³C shift requires selective P weathering: a 50% increase in P weathering with C/P = 1,000 gives burial ∼95%, δ¹³C +2.2‰, and O₂ +0.74 PAL (to 0.97 PAL at 417 Ma); a 25% increase with C/P = 2,000 gives burial ∼90%, δ¹³C +2.1‰, and O₂ +0.67 PAL; P weathering spikes with C/P = 2,000 peak at O₂ +0.72 PAL at 407 Ma.
Methods
- Revised COPSE biogeochemical model for coupled C, O, N, P, and S cycles and δ¹³C, with biological forcing factors: evolution/colonization (E), weathering enhancement (W), selective phosphorus weathering (F), and terrestrial C/P burial ratio (CP); sensitivity analyses varied geologic forcing and initial conditions.
- Trait-based spatial model of cryptogamic vegetation (bryophyte and lichen) driven by Late Ordovician (445 Ma) climate simulations at different atmospheric CO₂ and O₂; assumed CO₂ = 8 PAL, O₂ = 0.6 PAL, and no ice sheet mask to predict global NPP.
- Data compilation included the early charcoal record, molybdenum isotope record, carbonate δ¹³C spline fit, and bryophyte C/P ratios; experimental P weathering calculation used granite with the moss *Physcomitrella patens*.
Limitations
- Stated: direct evidence linking a phase of land colonization to enhanced weathering and a positive δ¹³C excursion is only established for the Silurian–Devonian boundary; alternative hypotheses for short-lived positive δ¹³C excursions should also be considered.
- Stated: the model does not capture the earlier Late Ordovician–Early Silurian δ³⁴S rise from ∼25 to ∼30‰; other processes not yet included warrant future consideration, such as the effect of increasing atmospheric mass on climate and effects on δ⁷Li and ⁸⁷Sr/⁸⁶Sr.
- Evident: P weathering amplification estimates are dominated by the unmeasured P content of biomass, though the factor must be >5.3; the hypothesis requires early plants to have been much more productive and globally extensive than previously assumed.
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Claims the paper makes
33 Not checked yet · 20 Own interpretation · 10 Own result · 7 No basis given · 2 Own method · 1 Supported so far
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In the paper
“The first appearance of fossil charcoal in the Late Silurian (11) and its ongoing occurrence through the Devonian (12) (Table S1), albeit rare and at low concentrations, indicates O2 > 15 -17% (vol) of the atmosphere (13) (or O2 > ∼ 0.7 PAL assuming a constant N2 reservoir) already by ∼ 420 -400 Ma.”
What the sources say
- Not checked yetcites [11] source
- Supportedcites [12] source
The Prídolí–Emsian section says that charcoal occurrences around 420–400 Ma indicate oxygen above present atmospheric levels, exceeding the cited 15–17% threshold. It also reports modeled values of 23%, 25%, and 22% at 420, 410, and 400 Ma, respectively. The paper does not extend that high-oxygen inference to the entire Devonian. (LLM, conf=0.90)
- Not checked yetcites [13] Belcher CM, McElwain JC (2008) Limits for combustion in low O2 redefine paleoatmospheric predictions for the Mesozoic. Science 321(5893):1197 -1200. source
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In the paper
“Data from modern bryophytes suggests this plentiful early plant material had a much higher molar C:P ratio ( ∼ 2,000) than marine biomass ( ∼ 100)”
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In the paper
“The original baseline model (10) predicts early Paleozoic O2 ∼ 0.23 PAL at a reference time of 445 Ma, supported by an organic carbon burial flux of ∼ 4 × 10 12 mol · y -1 (about half the present-day value) with δ 13 C = 0.03 ‰ .”
What the sources say
- Not checked yetcites [10] source
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In the paper
“Combining these effects in a model of long-term biogeochemical cycling, we reproduce a sustained + 2 ‰ increase in the carbonate carbon isotope ( δ 13 C) record by ∼ 445 Ma”
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- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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
“and predict a corresponding rise in O2 to present levels by 420 -400 Ma, consistent with geochemical data.”
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- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
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
“We use a trait-based ecophysiological model to predict that cryptogamic vegetation cover could have achieved ∼ 30% of today ' s global terrestrial net primary productivity by ∼ 445 Ma.”
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In the paper
“At atmospheric CO2 = 8 PAL, consistent with Late Ordovician glaciations (20), predicted global NPP is ∼ 19 GtC · y -1 (GtC, billion metric tons of carbon) (Fig. 2), ∼ 30% of today.”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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In the paper
“Alternatively, a series of P weathering spikes designed to reproduce the observed sequence of positive δ 13 C excursions (Fig. 1), combined with C/P = 2,000, produces a series of spikes in organic carbon burial and a peak increase of O2 of 0.72 PAL at 407 Ma (Fig. 3, black).”
plaindirect- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
In the paper
“this gives a biotic P weathering amplification factor ∼ 24 (range 15 -43), whereas previously we suggested up to 60 (20).”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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In the paper
“However, the P weathering amplification factor has to be > 5.3 (the ratio of dissolved phosphate entering solution in microcosms with moss to those without)”
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In the paper
“The presence of these rock-weathering capabilities in two early diverging lineages (mosses and liverworts) suggests it is an ancestral trait.”
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In the paper
“Both studies thus indicate preferential weathering of P relative to Ca and Mg (and corresponding alkalinity).”
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“Experimental work (20) has shown that a modern nonvascular plant, the moss Physcomitrella patens , amplifies the weathering of Ca ions 1.4- to 3.6-fold and Mg ions 1.5- to 5.4-fold from silicate rocks (granite -andesite), and amplifies the weathering of phosphorus from granite ∼ 24-fold (range 15 -43; Materials and Methods ).”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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“The molybdenum isotope record (9) indicates a fundamental shift in the redox state of the deep ocean from widespread anoxia to widespread oxygenation sometime during 435 -392 Ma (between the Early Silurian and the Middle Devonian).”
What the sources say
- Not checked yetcites [9] source
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In the paper
“Taken together, these data suggest that assuming C/P = 1,000 for early plants is conservative.”
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In the paper
“such that a given weathering flux of phosphorus could support more organic carbon burial.”
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- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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In the paper
“Furthermore, recent experiments suggest that early plants selectively increased the flux of phosphorus (relative to alkalinity) weathered from rocks.”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
- Not checked yetcites [21] Quirk J, et al. (2015) Constraining the role of early land plants in Palaeozoic weathering and global cooling. Proc Biol Sci , 10.1098/rspb.2015.1115.
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In the paper
“We also note that extensive shallow water phosphate deposits in the Late Ordovician (35) indicate a marked increase in phosphorus input to the ocean (20).”
What the sources say
- Not checked yetcites [35] Pope MC, Steffen JB (2003) Widespread, prolonged late Middle to Late Ordovician upwelling in North America: A proxy record of glaciation? Geology 31(1):63 -66. source
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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In the paper
“Here we show that the earliest plants, which colonized the land surface from ∼ 470 Ma onward, were responsible for this mid-Paleozoic oxygenation event, through greatly increasing global organic carbon burial -the net long-term source of O2.”
boosteddirect- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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
“This oxygen rise represents a permanent shift in regulatory regime to one where fire-mediated negative feedbacks stabilize high O2 levels.”
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In the paper
“Some models predict pO2 ∼ 1 present atmospheric level (PAL) already in the Early Paleozoic (7, 8), but this is at odds with data for widespread ocean anoxia (6, 9).”
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In the paper
“However, increases in carbonate weathering (enhanced by plants) and oxidative weathering (due to the rise in O2) increase the overall phosphorus weathering flux, roughly doubling the O2 rise due to terrestrial production of high C/P material alone.”
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In the paper
“Such a permanent shift requires a unidirectional driver that kicked in during the mid-Paleozoic.”
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In the paper
“Consistent with a rise in oxygen, the carbon isotope record (17) (Fig. 1) indicates a fundamental shift in baseline from ≤ 0 ‰ before the Late Ordovician to ∼ 2 ‰ from ∼ 445 Ma onward.”
What the sources say
- Not checked yetcites [17] Saltzman MR, Thomas E (2012) Carbon isotope stratigraphy. The Geologic Time Scale , eds Gradstein FM, Schmitz JGOD, Ogg GM (Elsevier, Boston), pp 207 -232. source
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In the paper
“The effect on O2 is constrained because atmospheric CO2 and temperature are reduced (20) such that the silicate weathering flux (and associated phosphorus flux) continues to match the degassing flux of CO2 (Fig. S3).”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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In the paper
“Our model can only reproduce Paleozoic geochemical data if the rise of the earliest land plants caused a major oxygenation event of the Earth ' s atmosphere and oceans by ∼ 400 Ma.”
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In the paper
“We attribute this mid-Paleozoic oxygenation event to a persistent global increase in organic carbon burial supported by the high C/P ratio of early land plant material, augmented by a plant-driven increase in P weathering flux relative to the weathering flux of alkalinity.”
plaindirect- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: The C/P ratio of early land plants was similar to that of extant bryophytes.
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In the paper
“However, because the initial O2 is now higher, the final O2 is also higher in all cases, and even scenarios without selective weathering of phosphorus could explain the appearance of charcoal (O2 > ∼ 0.7 PAL).”
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In the paper
“However, to reproduce the observed δ 13 C + 2 ‰ shift requires the inclusion of some selective weathering of phosphorus by early plants.”
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In the paper
“which is already considerably greater than the amplification factors for Ca = 1.4 and Mg = 1.5 from granite, indicating selective weathering of P.”
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In the paper
“For the earliest land plants to be responsible for such a major mid-Paleozoic oxygenation event requires that they were much more productive and globally extensive than has been previously assumed (7, 10, 33).”
What the sources say
plainconditional- Asserted: passes — The authors put it forward as true.
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In the paper
“However, direct evidence linking a phase of land colonization to enhanced weathering and a positive δ 13 C excursion has only thus far been established for the Silurian -Devonian boundary excursion (36).”
What the sources say
- Not checked yetcites [36] Ma ł kowski K, Racki G (2009) A global biogeochemical perturbation across the Silurian -Devonian boundary: Ocean -continent -biosphere feedbacks. Palaeogeogr Palaeoclimatol Palaeoecol 276(1 -4):244 -254. source
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In the paper
“Clearly these estimates are dominated by the unmeasured P content of biomass.”
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- It may state two separate claims as one. 33
- Probably not a substantial claim. 14
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In the paper
“If instead we assume that buried early plant matter had C/P = 2,000, then given their productivity, even with no effect on weathering fluxes, this increases global organic carbon burial by ∼ 50%, δ 13 C by 1.1 ‰ , and atmospheric O2 by 0.27 PAL (Fig. 3, cyan).”
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- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
None of the sources cited for this claim have been checked yet.
In the paper
“In the original COPSE model (10), predicted NPP only reaches ∼ 5% of today ' s value in the Late Ordovician and Silurian, but when we assume a stronger Late Ordovician phase of land colonization by nonvascular plants (following ref. 20; SI Materials and Methods ), then COPSE predicts global NPP 30 -40% of today (Fig. 3 A ), consistent with the detailed spatial model.”
What the sources say
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In the paper
“If we include in COPSE an effect of early plants on silicate weathering following ref. 20, assuming C/P = 1,000, this increases organic carbon burial by ∼ 35%, δ 13 C by 0.7 ‰ , and O2 by 0.18 PAL (Fig. 3, magenta).”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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.
- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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
“In COPSE, this advent of early land plants alone, with no assumed effect on weathering fluxes, and assumed C/P = 1,000, increases total organic carbon burial by ∼ 25%, δ 13 C by 0.5 ‰ , and atmospheric O2 by 0.11 PAL (Fig. 3, blue).”
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- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
In the paper
“However, we estimate much higher global NPP (Fig. 2) and weathering potential (32).”
What the sources say
- Not checked yetcites [32] Porada P, et al. (2016) High potential for weathering and climate effects of nonvascular vegetation in the Late Ordovician. Nat Commun , 10.1038/ncomms12113. source
hedged- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“Predicted NPP is sensitive to variations in CO2 and climate (Fig. S1), ice sheet cover (Fig. S2), and O 2 (Table S2), but is consistently higher than the 4.3 GtC · y -1 (7% of today) estimated elsewhere (33).”
What the sources say
- Not checked yetcites [33] Edwards D, Cherns L, Raven JA (2015) Could land-based early photosynthesizing ecosystems have bioengineered the planet in mid-Palaeozoic times? Palaeontology 58(5): 803 -837. source
plaincorrelational- Asserted: passes — The authors put it forward as true.
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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
“The mean moss biomass in the biotic microcosms was 14.390 mg”
plain- Asserted: passes — The authors put it forward as true.
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Probably not a substantial claim. The paper’s conclusions may not depend on it.
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
“Assuming that early plants caused a sustained 50% increase in phosphorus weathering relative to bulk rock dissolution, with C/P = 1,000, increases total organic carbon burial by ∼ 95%, δ 13 C by 2.2 ‰ , and O2 by 0.74 PAL (to 0.97 PAL at 417 Ma; Fig. 3, yellow).”
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.
Probably not a substantial claim. It may state two separate claims as one.
- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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
“Varying the uplift and degassing forcing of the model within plausible bounds only causes ± 0.08 PAL variation in O2 about the initial state (Fig. S4), although it does cause the effect of the same early plant forcing scenario to range over + 0.4 to 1.0 PAL O2 (Table S4).”
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“The relatively high global NPP results obtained are consistent with present-day cryptogamic covers providing ∼ 7% of global NPP, despite making up only 1% of terrestrial vegetation by mass (90) and being restricted to relatively resource-poor habitats, while also operating in an atmosphere with a low CO2/O2 ratio.”
What the sources say
- Not checked yetcites [90] Elbert W, et al. (2012) Contribution of cryptogamic covers to the global cycles of carbon and nitrogen. Nat Geosci 5(7):459 -462. source
plaincorrelational- Asserted: passes — The authors put it forward as true.
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Probably not a substantial claim. The paper’s conclusions may not depend on it. 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
“Our model makes additional predictions that can be tested against geochemical data -notably, it predicts a decline in pyrite sulfur burial and associated drop in δ 34 S and increases in seawater SO4 concentration and C/S burial ratio with the rise of the earliest plants (Fig. S5).”
plaindirect- Asserted: passes — The authors put it forward as true.
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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
“Assuming that buried early plant matter had a higher C/P = 2,000 causes larger increases in total organic carbon burial ∼ 60%, δ 13 C + 1.2 ‰ , and atmospheric O2 + 0.35 PAL (Fig. 3, green).”
plaindirect- Asserted: passes — The authors put it forward as true.
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- 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 state two separate claims as one.
- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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 amplification factors for Ca = 1.4 and Mg = 1.5 from granite”
plain- Asserted: passes — The authors put it forward as true.
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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
“Including an additional negative feedback on O2, from increased marine organic C/P burial ratios under anoxic waters (37), increases its initial early Paleozoic level to 0.54 PAL and reduces the effect of the same biological forcing scenarios on O2 by ∼ 10 -30%, giving a maximum increase of + 0.63 PAL (Table S5).”
What the sources say
- Not checked yetcites [37] Van Cappellen P, Ingall ED (1996) Redox stabilization of the atmosphere and oceans by phosphorus-limited marine productivity. Science 271:493 -496. source
plaindirect- 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.
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
“Assuming a sustained 25% increase in phosphorus weathering relative to bulk rock and C/P = 2,000 increases organic carbon burial by ∼ 90%, δ 13 C by 2.1 ‰ , and O2 by 0.67 PAL (Fig. 3, red).”
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.
Probably not a substantial claim. It may state two separate claims as one.
- Rests on an assumption: The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
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
“which assuming 0.43 gC/g biomass and C/P = 2,000 (Table S3) suggests 0.26 μ mol P in biomass, or for C/P = 1,000 -4,000, 0.13 -0.52 μ mol P in biomass”
hedgedSingle case- Asserted: passes — The authors put it forward as true.
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Probably not a substantial claim. It may state two separate claims as one.
In the paper
“Subsequent experiments (21) with the modern liverwort Marchantia paleacea found a 2.5- to 7-fold amplification of Ca weathering and a 9- to 13-fold amplification of P weathering from basalt.”
What the sources say
- Not checked yetcites [21] Quirk J, et al. (2015) Constraining the role of early land plants in Palaeozoic weathering and global cooling. Proc Biol Sci , 10.1098/rspb.2015.1115.
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
“Furthermore, Early Devonian coaly shales indicate extensive peatlands 410 -400 Ma and have C/N of 44 -119 (28), comparable to that in modern peatlands where N/P and C/P ratios tend to increase with depth to C/P > 3,000 (34).”
What the sources say
- Not checked yetcites [28] Kennedy KL, et al. (2013) Lower Devonian coaly shales of northern New Brunswick, Canada: Plant accumulations in the early stages of Terrestrial colonization. J Sediment Res 83(12):1202 -1215. source
- Not checked yetcites [34] Wang M, Moore TR, Talbot J, Richard PJH (2014) The cascade of C:N:P stoichiometry in an ombrotrophic peatland: from plants to peat. Environ Res Lett 9(2):024003. source
hedgedcorrelational- 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
“The evolution of land plants is the obvious candidate”
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: fails — It may be too vague to check against evidence.
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Probably not a substantial claim. It may be too vague to check against evidence.
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
“Here we show that neither scenario is correct.”
boosted- 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
“However, plants and their associated mycorrhizal fungi can increase phosphorus weathering (20 -22), and this could be sustained on longer timescales if they preferentially weather phosphorus relative to alkalinity.”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
- Not checked yetcites [21] Quirk J, et al. (2015) Constraining the role of early land plants in Palaeozoic weathering and global cooling. Proc Biol Sci , 10.1098/rspb.2015.1115.
- Not checked yetcites [22] Lenton TM, Watson AJ (2000b) Redfield revisited: 2. What regulates the oxygen content of the atmosphere? Global Biogeochem Cycles 14(1):249 -268. source
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.
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It may state two separate claims as one.
In the paper
“The COPSE model we adapt here (10) predicts Early Paleozoic pO2 ∼ 0.2 -0.5 PAL consistent with redox proxy data but, like the other models (7, 8), it does not predict a rise in oxygen until the advent of forests starting ∼ 385 Ma, and continuing until ∼ 300 Ma, which is too late to explain marked changes in geochemical data that occur before ∼ 390 Ma (Fig. 1).”
What the sources say
- Not checked yetcites [10] source
plain- 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.
None of the sources cited for this claim have been checked yet.
In the paper
“Given that earlier plants developed peatlands (28), and had rock-weathering capabilities (20, 21), they could also have affected the global carbon cycle (18, 20).”
What the sources say
- Not checked yetcites [28] Kennedy KL, et al. (2013) Lower Devonian coaly shales of northern New Brunswick, Canada: Plant accumulations in the early stages of Terrestrial colonization. J Sediment Res 83(12):1202 -1215. source
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
- Not checked yetcites [21] Quirk J, et al. (2015) Constraining the role of early land plants in Palaeozoic weathering and global cooling. Proc Biol Sci , 10.1098/rspb.2015.1115.
hedgedconditional- Asserted: passes — The authors put it forward as true.
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- 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
“Though there are many subsequent δ 13 C fluctuations, including drops back to 0 ‰ , for example, at ∼ 400 Ma, the long-term mean δ 13 C remains ∼ 2 ‰ throughout the rest of the Paleozoic, the Mesozoic, and the Early Cenozoic (17), indicating a sustained increase in global organic carbon burial.”
What the sources say
- Not checked yetcites [17] Saltzman MR, Thomas E (2012) Carbon isotope stratigraphy. The Geologic Time Scale , eds Gradstein FM, Schmitz JGOD, Ogg GM (Elsevier, Boston), pp 207 -232. source
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.
- Rests on an assumption: Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
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 persistent oxygenation of the ocean and appearance of charcoal can be explained by a rise in atmospheric oxygen occurring by ∼ 400 Ma”
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.
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
“Land plants typically have a much higher molar C/P ratio ( ∼ 1,000) than marine organic matter ( ∼ 100) due to carbon-rich but phosphorus-poor structural compounds such as sporopollenin, lignin, and, in their fungal mycorrhizal symbionts, chitin; therefore, they can support an increased organic carbon burial flux for the same P weathering flux.”
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.
- Rests on an assumption: On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
None of the sources cited for this claim have been checked yet.
In the paper
“The P weathering flux is partly tied to bulk silicate weathering, for example, due to the dissolution of apatite inclusions in silicate rocks, and the silicate weathering flux of alkalinity is in turn set by negative feedback in the longterm carbon cycle, so is ultimately controlled by the degassing input of CO2 on timescales ≥ 1 My (7, 10).”
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.
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
“Instead, the earliest plants, which colonized the land from 470 Ma onward, first increased atmospheric oxygen to present levels by 400 Ma, and this instigated fire-mediated feedbacks that have stabilized high oxygen levels ever since, shaping subsequent evolution.”
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.
None of the sources cited for this claim have been checked yet.
In the paper
“This ocean oxygenation is also supported by a Silurian increase in the C/S ratio of shales (15), and a shift in iron speciation data sometime during 435 -387 Ma (6).”
What the sources say
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.
None of the sources cited for this claim have been checked yet.
In the paper
“The early charcoal record (Table S1) was compiled from the literature (11, 12, 28, 44 -72) using existing compilations (12, 44 -47) and checking them where possible against the original sources.”
What the sources say
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.
None of the sources cited for this claim have been checked yet.
In the paper
“This finding is broadly consistent with the sulfur isotope ( δ 34 S) record (38 -40), which shows a marked decline through the Silurian -Early Devonian from ∼ 30 to ∼ 18 ‰ , although available data also suggest an earlier Late Ordovician -Early Silurian rise from ∼ 25 to ∼ 30 ‰ , which the present model does not capture.”
What the sources say
- Not checked yetcites [38] Prokoph A, Shields GA, Veizer J (2008) Compilation and time-series analysis of a marine carbonate δ 18O, δ 13C, 87Sr/86Sr and δ 34S database through Earth history. Earth Sci Rev 87(3 -4):113 -133. source
- Not checked yetcites [39] Gill BC, Lyons TW, Saltzman MR (2007) Parallel, high-resolution carbon and sulfur isotope records of the evolving Paleozoic marine sulfur reservoir. Palaeogeogr Palaeoclimatol Palaeoecol 256(3 -4):156 -173. source
- Not checked yetcites [40] Jones DS, Fike DA (2013) Dynamic sulfur and carbon cycling through the end-Ordovician extinction revealed by paired sulfate -pyrite δ 34S. Earth Planet Sci Lett 363: 144 -155. source
hedgedcorrelational- 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.
- Based: passes — The paper gives a reason why it holds.
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
“Sensitivity analyses ( SI Materials and Methods ) indicate that our results are robust.”
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.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
None of the sources cited for this claim have been checked yet.
In the paper
“Uncertainties shown in Fig. 1 represent 2 SD of the mean (analytical precision) plus the propagated uncertainty from matching in-house reference materials to the universal standard NIST SRM 3136 where seawater display δ 98/95 Mo = 2.3 ‰ (75, 76).”
What the sources say
- Not checked yetcites [75] Goldberg T, et al. (2013) Resolution of inter-laboratory discrepancies in Mo isotope data: An intercalibration. J Anal At Spectrom 28(5):724 -735. source
- Not checked yetcites [76] Nägler TF, et al. (2014) Proposal for an international molybdenum isotope measurement standard and data representation. Geostand Geoanal Res 38(2):149 -151. source
plain- Asserted: passes — The authors put it forward as true.
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- Load-bearing: fails — The paper’s conclusions may not depend on it.
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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
“The δ 13 C record suggests this increase in organic carbon burial was essentially permanent, producing a new dynamically stable state for atmospheric O2.”
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.
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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
“new fire-mediated negative feedbacks on O2 were instigated that have played a key role in stabilizing atmospheric O2 concentration up to the present day (22, 43).”
What the sources say
- Not checked yetcites [22] Lenton TM, Watson AJ (2000b) Redfield revisited: 2. What regulates the oxygen content of the atmosphere? Global Biogeochem Cycles 14(1):249 -268. source
- Not checked yetcites [43] Kump LR (1988) Terrestrial feedback in atmospheric oxygen regulation by fire and phosphorus. Nature 335:152 -154. source
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.
None of the sources cited for this claim have been checked yet.
In the paper
“The model is consistent with proxy reconstructions of seawater SO4 concentration, which suggest an Ordovician -Silurian rise from ∼ 6 to ∼ 10 mM (41), and with a Silurian increase in the molar C/S ratio of shales from ∼ 5 to ∼ 16 (15).”
What the sources say
- Not checked yetcites [41] Algeo TJ, Luo GM, Song HY, Lyons TW, Canfield DE (2015) Reconstruction of secular variation in seawater sulfate concentrations. Biogeosciences 12(7):2131 -2151. source
- Not checked yetcites [15] Berner RA, Raiswell R (1983) Burial of organic carbon and pyrite sulfur in sediments over phanerozoic time: A new theory. Geochim Cosmochim Acta 47(5):855 -862. source
hedgedcorrelational- 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
“We explored the sensitivity of predicted global NPP to variations in atmospheric CO2 and corresponding climate state (Fig. S1), to constraining vegetation cover with extensive Late Ordovician ice sheet cover (Fig. S2), and to varying O2 in combination with CO2 (Table S2).”
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. 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 this new steady state, oxidative weathering was increased (becoming less sensitive to variations in O2)”
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.
In the paper
“In our previously reported (20) weathering experiments with granite, the mean amounts of phosphate weathered into aqueous solution were as follows: control microcosms = 0.0137 μ mol P, biotic microcosms = 0.0726 μ mol P.”
What the sources say
- Not checked yetcites [20] Lenton TM, Crouch M, Johnson M, Pires N, Dolan L (2012) First plants cooled the Ordovician. Nat Geosci 5(2):86 -89. source
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.
Probably not a substantial claim.
In the paper
“Then, in a sensitivity analysis, we considered uncertainty in geologic forcing (91), and alternative initial conditions (altering the feedback structure of the model).”
What the sources say
- Not checked yetcites [91] Royer DL, Donnadieu Y, Park J, Kowalczyk J, Goddéris Y (2014) Error analysis of CO2 and O2 estimates from the long-term geochemical model GEOCARBSULF. Am J Sci 314(9):1259 -1283. source
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.
The paper relies on this without support.
The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks.
“The major long-term source of oxygen to the atmosphere is the burial of organic carbon in sedimentary rocks (which represents the net flux of photosynthesis minus various pathways of respiration and oxidation).”
The paper relies on this without support.
Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks (δ13C).
“Increases in global organic carbon burial are recorded as positive shifts in the isotopic composition of carbonate rocks ( δ 13 C).”
The paper relies on this without support.
On long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the molar ratio of carbon-to-phosphorus in material that is buried.
“In simple terms, on long timescales, the global organic carbon burial flux is determined by the supply flux of the ultimate limiting nutrient phosphorus from weathering and the (molar) ratio of carbon-to-phosphorus in material that is buried”
The paper relies on this without support.
The C/P ratio of early land plants was similar to that of extant bryophytes.
“supported by the high C/P ratio of early land plant material”
“The C/P ratio of extant bryophytes (Table S3) was compiled from data in the literature (34, 80 -88).”
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?
In the citing paper
“Sedimentary recycling of organic carbon during the Archaean and Proterozoic can thus help reconcile increases in oxygen, and presumed associated increases in biological productivity, with the lack of a secular trend in δ13Ccarb until the Phanerozoic17 (where there is a shift from 0 to 2‰ associated with the rise of land plants13).”
From Atmospheric oxygen regulation at low Proterozoic levels by incomplete oxidative weathering of sedimentary organic carbon (2017) · cites this paper as [13]
In the citing paper
“The rise of oxygen to present levels simply required an increase in organic carbon burial rate, which may have begun in the Neoproterozoic Era10, but in our model was not completed until the mid-Palaeozoic Era with the colonization of the land by plants and fungi, liberating nutrient phosphorus from rocks and producing high C/P material for burial1113.”
From Atmospheric oxygen regulation at low Proterozoic levels by incomplete oxidative weathering of sedimentary organic carbon (2017) · cites this paper as [13]
Citations
Cites
The rise of oxygen in Earth's early ocean and atmosphere
Lyons, T. W., Reinhard, C. T., & Planavsky, N. J. (2014) · Nature · doi:10.1038/nature13068 · Cited by 2,810 · cited 2×
“Proc Natl Acad Sci USA 111(2):734–739.”
BackgroundGEOCARBSULF: A combined model for Phanerozoic atmospheric O2 and CO2
Berner, R. A. (2006) · Geochimica et Cosmochimica Acta · doi:10.1016/j.gca.2005.11.032 · Cited by 1,120
Burial of organic carbon and pyrite sulfur in sediments over phanerozoic time: a new theory
Berner, R. A., & Raiswell, R. (1983) · Geochimica et Cosmochimica Acta · doi:10.1016/0016-7037(83)90151-5 · Cited by 1,044
Late-Neoproterozoic Deep-Ocean Oxygenation and the Rise of Animal Life
Canfield, D. E., Poulton, S. W., & Narbonne, G. M. (2007) · Science · doi:10.1126/science.1135013 · Cited by 1,000 · cited 2×
“Ferruginous shales (77) are defined by the Fe speciation proxy when FeHR/FeT > 0.”
BackgroundContribution of cryptogamic covers to the global cycles of carbon and nitrogen
Elbert, W., Weber, B., Burrows, S., Steinkamp, J., Büdel, B., Andreae, M. O., & Pöschl, U. (2012) · Nature Geoscience · doi:10.1038/ngeo1486 · Cited by 957
A New Model for Atmospheric Oxygen Over Phanerozoic Time
Berner, R. A., & Canfield, D. E. (1989) · American Journal of Science · doi:10.2475/ajs.289.4.333 · Cited by 756
Scott, C., & Lyons, T. W. (2012) · Chemical Geology · doi:10.1016/j.chemgeo.2012.05.012 · Cited by 745 · cited 1×
“Euxinic shales are defined (78, 79) by theMo enrichment proxy whenMo > 25 ppm (white circles in Fig.”
MethodThe Neoproterozoic oxygenation event: Environmental perturbations and biogeochemical cycling
Och, L. M., & Shields-Zhou, G. A. (2012) · Earth-Science Reviews · doi:10.1016/j.earscirev.2011.09.004 · Cited by 646
Statistical analysis of iron geochemical data suggests limited late Proterozoic oxygenation
Sperling, E. A., Wolock, C. J., Morgan, A. S., Gill, B. C., Kunzmann, M., Halverson, G. P., Macdonald, F. A., Knoll, A. H., & Johnston, D. T. (2015) · Nature · doi:10.1038/nature14589 · Cited by 637 · cited 3×
“This ocean oxygenation is also supported by a Silurian increase in the C/S ratio of shales (15), and a shift in iron speciation data sometime during 435–387 Ma (6).”
BackgroundCOPSE: A new model of biogeochemical cycling over Phanerozoic time
Bergman, N. M. (2004) · American Journal of Science · doi:10.2475/ajs.304.5.397 · Cited by 599
Research works printed but not linked: 4
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Cited by
Sorted by citations
The timescale of early land plant evolution
Morris, J. L., Puttick, M. N., Clark, J., Edwards, D., Kenrick, P., Pressel, S., Wellman, C. H., Yang, Z., Schneider, H., & Donoghue, P. C. J. (2018) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1719588115 · Cited by 926
“These dates are older than those used in the latest biogeochemical models (6, 8), and thus our results have implications for simulations of atmospheric chemistry and climate during the Paleozoic.”
Ancestral alliances: Plant mutualistic symbioses with fungi and bacteria
Martin, F. M., Uroz, S., & Barker, D. G. (2017) · Science · doi:10.1126/science.aad4501 · Cited by 591
“colonization event in the Middle to Upper Ordovician (~443 to 470 Ma) (16, 17).”
BackgroundExtending full-plate tectonic models into deep time: Linking the Neoproterozoic and the PhanerozoicPreprint
Merdith, A., Williams, S. E., Collins, A. S., Tetley, M. G., Mulder, J. A., Blades, M., Young, A., Armistead, S., Cannon, J., Zahirovic, S., et al. (2020) · Earth-Science Reviews · doi:10.1016/j.earscirev.2020.103477 · Cited by 544
COPSE reloaded: An improved model of biogeochemical cycling over Phanerozoic time
Lenton, T. M., Daines, S. J., & Mills, B. J. W. (2018) · Earth-Science Reviews · doi:10.1016/j.earscirev.2017.12.004 · Cited by 350
“This requires a substantial 1304 secular increase in organic carbon burial, which is here associated with the earliest, non-vascular 1305 land plants (Lenton et al., 2016) (unlike in the original COPSE model where it is associated with the 1306 later evolution of trees).”
BackgroundMethodResultInfluentialSelf-citationOxygenation history of the Neoproterozoic to early Phanerozoic and the rise of land plants
Wallace, M. W., Hood, A. V., Shuster, A., Greig, A., Planavsky, N. J., & Reed, C. P. (2017) · Earth and Planetary Science Letters · doi:10.1016/j.epsl.2017.02.046 · Cited by 299
Metadata
- Authors
- Lenton, T. M., Dahl, T. W., Daines, S. J., Mills, B. J. W., Ozaki, K., Saltzman, M. R., & Porada, P.
- Affiliations
- University of Exeter (GB)
- University of Copenhagen (DK)
- University of Leeds (GB)
- Georgia Institute of Technology (US)
- The Ohio State University (US)
- Stockholm University (SE)
- ORCID
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2016-08-15
- Volume
- 113
- Issue
- 35
- Pages
- 9704-9709
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC5024600
- OpenAlex
- W2508469640
- Cited by
- 343
- References
- 92
- Citations by year
- 2026: 25 · 2025: 33 · 2024: 45 · 2023: 48 · 2022: 47 · 2021: 34 · 2020: 21 · 2019: 32 · 2018: 31 · 2017: 23 · 2016: 4
- FWCI
- 24.94
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Research at the University of Copenhagen (University of Copenhagen) (publishedVersion)
- White Rose Research Online (University of Leeds, The University of Sheffield, University of York) (acceptedVersion)
- Open Research Exeter (University of Exeter) (acceptedVersion)
- Figshare (submittedVersion)
- Tokyo Tech Research Repository (Tokyo Institute of Technology) (submittedVersion)
- Funders
- Leverhulme Trust (RPG-2013-106)
- Natural Environment Research Council (NE/I005978/2)
- Royal Society (Wolfson Research Merit Award)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Environmental Science › Global and Planetary Change › Earth Systems and Cosmic Evolution
- Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geological and Geochemical Analysis
- Keywords
- atmospheric oxygenation, early land plants, organic carbon burial, bryophytes, terrestrial net primary productivity, C:P ratio, carbonate carbon isotopes, biogeochemical cycles, fire feedbacks, redox proxies
- MeSH terms
- Origin of Life, Atmosphere, Carbon Dioxide, Carbon Isotopes, Biological Evolution, Oceans and Seas, Oxidation-Reduction, Oxygen, Phosphorus, Photosynthesis, Soil, Models, Statistical, Biomass, Earth, Planet, Geologic Sediments, Embryophyta, History, Ancient
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 2026-10-08, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-08 (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.
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