User:Pengxiao Xu/sandbox

Fig. Main reservoirs and fluxes (in unit 10¹² mol/yr) of the modern global oxygen (O₂ specifically) cycle. Four main reservoirs, i.e., terrestiral biosphere, marine biosphere, lithosphere, and atmosphere are shown in the figure. Note that the brown bald mountain in the left side of this figure also represents a part of lithosphere. Main fluxes between these reservoirs are shown in colored arrows, where the green arrows are related to the terrestrial biosphere, blue arrows are related to the marine biosphere, black arrows are related to the lithosphere, purple arrow is related to the space (not a reservoir, but also contributes to the atmosphere oxygen level). The value of photosynthesis or net primary productivity (NPP) can be estimated through the variation in the abundance and isotopic composition of atmospheric oxygen The rate of organic carbon burial can be derived by estimating the flux of volcanic and hydrothermal carbon.

Oxygen Cycle Article Evaluation

Content

The content of this article is generally nice. Information are well presented, two figures are shown, different reservoirs and fluxes are listed, important reactions are provided, and no distraction exists. The article is well written in a concise way and is easy to understand.

But, there are still some shortcomings as far as I concerned.

1. The first figure is too brief, and no amount of flux is shown on it.
2. Some of its data is outdated, such as the reservoir capacities and residence time. The author cited Walker's book published in 1980 while there is a more recent review about global oxygen cycle written by Kasting and Canfield in 2012.

Tone

This article is written in a neutral tone and I observed no biased statement. All the statements are based on the data. Though the data itself might be inaccurate or outdated, there is no problem about the writing style.

Source

There are many problems with the source of this article.

1. Six different sources are listed in the Reference part, which is good but not enough in my opinion, especially only one of them is a published academic paper.
2. The First source is an article in Scientific American and has a link followed, but the link has already expired. I can't see the article by clicking the link provided.
3. Sources are a bit of outdated. Two Scientific American articles are published in 2003 and 1970 respectively and the academic paper is from a book published in 1980. More recent works is available, e.g. Kasting & Canfield, 2012.
4. The fourth source is actually notes taken in a class, which cannot be considered as very reliable.

Talk Page

The talk page of this article is quite good, some relative questions are discussed and mistakes are corrected.

References

[1] Petsch, Steven (2003). "The Global Oxygen Cycle". Treatise on Geochemistry. 8:515-555 https://doi.org/10.1016/B0-08-043751-6/08159-7

[2] Reinhard, Christopher T., Planavsky, Noah J., Olson, Stephanie L., Lyons, Timothy W., and Erwin, Douglas H. (2016). "Earth’s Oxygen Cycle and the Evolution of Animal Life." Proceedings of the National Academy of Sciences 113(32): 8933-38. https://dx.doi.org/10.1073/pnas.1521544113

[3] Keeling, Ralph F. (1995). "The Atmospheric Oxygen Cycle: The Oxygen Isotopes of Atmospheric Co 2 and 0 2 and the 0 2 /N 2 Ratio." 33:1253. https://dx.doi.org/10.1029/95rg00438

[4] Kasting, James F. and Canfield, Donald E (2012). "The Global Oxygen Cycle." Fundamentals of Geobiology." ch7:92-104. https://doi.org/10.1002/9781118280874.ch7

[5] Holland, Heinrich D (2002). "Volcanic gases, black smokers, and the Great Oxidation Event." Geochimica et Cosmochimica Acta 66(21): 3811-3826. https://doi.org/10.1016/S0016-7037(02)00950-X

[6] Lasaga, Antonio C., and Hiroshi Ohmoto (2002). "The oxygen geochemical cycle: dynamics and stability." Geochimica et Cosmochimica Acta 66(3): 361-38. https://doi.org/10.1016/S0016-7037(01)00685-8

[7] Najjar, Raymond G., and Ralph Keeling F. (2000). "Mean annual cycle of the air‐sea oxygen flux: A global view." Global biogeochemical cycles 14(2): 573-584. https://doi.org/10.1029/1999GB900086

[8] Walker, James CG (1986). "Global geochemical cycles of carbon, sulfur and oxygen." Marine Geology 70(1-2): 159-174.https://doi.org/10.1016/0025-3227(86)90093-9

[9] Sleep, Norman H (2005). "Dioxygen over geological time." Metal Ions in Biological Systems, Biogeochemical Cycles of Elements. CRC Press, 43: 92-116. https://www.taylorfrancis.com/books/9780824751999/chapters/10.1201%2F9780824751999-7

[10] Betts, J. N., and Holland, H. D. (1991). "The oxygen content of ocean bottom waters, the burial efficiency of organic carbon, and the regulation of atmospheric oxygen." Global and planetary change. 5(1-2): 5-18. https://doi.org/10.1016/0921-8181(91)90123-E