Talk:Coal/Archive 3

Archive 1

Archive 2

Archive 3

History

This entire section starts off decent but then meanders off and ignores the entire rest of the world to focus on Britain, with one tiny mention of the EU late in the section. This section needs to be greatly expanded. Theroguex (talk) 06:16, 23 October 2020 (UTC)

sulfur dioxide is oxidized to gaseous H2SO2

The article says: sulfur dioxide is oxidized to gaseous H2SO2, but that seems not like oxidation, but more like reduction. Oxidation should give SO3. Gah4 (talk) 06:36, 16 November 2020 (UTC)

When this was added (several years ago now) it came with a source that actually says H2SO4, so presumably that was just a typo. Thanks for pointing it out. I've also tagged the global emission number as potentially needing an update. Mikenorton (talk) 11:12, 16 November 2020 (UTC)

Formation

https://www.pnas.org/content/113/9/2442 as well as other sources suggest that the theory about coal formation being caused by lack of lignin-metabolising organisms is false. The paragraph about this already feels out of place in the context of the segment and I feel it should be removed. 2001:8B0:A7F4:5A22:5CFA:16BF:D829:BB2E (talk) 16:17, 8 September 2020 (UTC)

It's mentioned often enough that I think it needs refuting, thanks for the paper, I have added the paper to the article. Hemiauchenia (talk) 23:05, 30 November 2020 (UTC)

How soundly has it been refuted? If it's solid, then it should be a separate paragraph later in the section. --Kent G. Budge (talk) 00:00, 1 December 2020 (UTC)

Meh, I decided to be WP:BOLD and just make the suggested change. I do think we need some sources showing this hypothesis continuing to be mooted, and it might be nice to have something really solid in the way of a review article that establishes a consensus that it has been refuted. The one article is pretty reliable but it's still just one article. I note that McGhee (2018) quotes Shaw (2014) regarding the evolution of insect consumers of wood, takes it as established that wood-rotting fungi were already around in the early Carboniferous, and doesn't mention lignin at all -- just wood generally. --Kent G. Budge (talk) 00:10, 1 December 2020 (UTC)

Lignin degradation

The article claims:

"The ability to produce lignin led to the evolution of the first trees. But bacteria and fungi did not immediately evolve the ability to decompose lignin, so the wood did not fully decay but became buried under sediment, eventually turning into coal. About 300 million years ago, mushrooms and other fungi developed this ability, ending the main coal-formation period of earth's history. However, a 2016 study largely refuted this idea, finding extensive evidence of lignin degradation during the Carboniferous, and that shifts in lignin abundance had no impact on coal formation. They suggested that climatic and tectonic factors were a more plausible explanation."

Actually, that is not true. The original article where the claim was made is the 2012 article by Floudas et al in Science, whic was cited 1402 times, and recent citations do not create an impression that the main idea was "largely refuted". The article by Nilsen that ostensibly refutes this idea was cited just 177 times, and there is no indication that Nielsen's is accepted by scientific community. To check that, I took the recent review where both Floudas and Nilsen articles were analyzed (https://doi.org/10.1016/j.copbio.2018.11.011), which was cited 77 times (and that is very good for a review article), and the review says:

"Based on comparative genomics and molecular clock analyses, the evolution of lignin-decomposition capacities of fungi is thought to have originated from the ancestor of Auriculariales and related fungi during late Carboniferous [approximately 295 million years ago (Mya)] [26,27�], when the reduction of coal deposition began, thereby supporting the above-mentioned lag hypothesis [27�]. However, it was recently proposed that the accumulation of coal was controlled by a combination of both climatic and tectonic factors, and the evolution of fungal lignin-degrading traits could have potentially occurred before the Carboniferous period [25]. To gain new insights into the evolutionary era of the lignin-degrading capacity of fungi, an ancestral enzyme resurrection approach has been conducted with peroxidase [28��,29]. In this approach, the ancestral sequence was reconstructed based on a phylogenetic analysis with a maximum likelihood for 113 peroxidase sequences [28��]. Lignin peroxidase and versatile peroxidase are phylogenetically distant, despite the fact that both enzymes share an exposed catalytic tryptophan, which is necessary for the electron transfer from non-phenolic lignin to an internal heme, thus enabling the oxidation of non-phenolic lignin [30–32]. Resurrected enzymes with catalytic tryptophan were able to oxidize veratryl alcohol, a non-phenolic lignin model substrate, and this type of enzymes were estimated to be appeared approximately 200 Mya [28��]. In contrast, more ancient peroxidases, including the peroxidase from common ancestor of the Polyporales do not have a catalytic tryptophan and lack catalytic activity towards nonphenolic lignin. However, they are able to oxidize Mn2+, a phenolic lignin model compound (2,6-dimethoxyphenol), and a low-redox potential dye (2,20-azinobis[3-ethylbenzothia-zoline-6-sulfonate]). Therefore, the emergence of peroxidases containing catalytic tryptophan is believed to be the evolutionary point at which fungi acquired the capacity to carry out non-phenolic lignin depolymerization."

This means later works confirm conclusions made by Floudas (ref 27) that a full scale lignin degradation capabilities were developed by fungi at ca 200 MYa, and do not confirm conclusions by Nilsen (ref 25). I am going to change the article accordingly.--Paul Siebert (talk) 05:02, 21 January 2022 (UTC)

References

Semi-protected edit request on 25 August 2022

Under the dehydration chemistry examples, this is listed 2 R–OH → R–O–R + H2O 66.113.3.30 (talk) 20:29, 25 August 2022 (UTC)

 Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Nythar^T.C 00:02, 26 August 2022 (UTC)

Semi-protected edit request on 27 October 2022

Correct the last line in the fifth paragraph in the “Formation” subsection in the “Geology” section to read “300 MYa” rather than the incorrect “200 MYa.” The source cited (#30) itself says “290 MYa.” 2600:1700:B750:7480:7961:4BCF:93B7:5E65 (talk) 05:24, 27 October 2022 (UTC)

Not done. The source has "The angiosperm appearance (140–250 Mya) (41) roughly corresponds with the age of the two most recent ancestors of major clades B and D of ligninolytic peroxidases in Polyporales (∼200 Mya) that subsequently incorporated the exposed catalytic tryptophan almost at the same time". --Mvqr (talk) 10:24, 27 October 2022 (UTC)

Science

Formation of coal 2405:204:312F:D7A8:0:0:2955:90A0 (talk) 05:01, 4 January 2023 (UTC)

Hylaversicolor (talk) 18:11, 3 February 2023 (UTC)my evaluation

Which article are you evaluating?

Talk:Coal

Why you have chosen this article to evaluate?

I have chosen this article to evaluate because it has been rated as C-Class by WikiProject Vital Articles. A major weakness of the article is related to lignin degradation, and there is a debate on the talk page about when fungi evolved the capability to decompose lignin. In the history section of the article, there appears to be a contradictory statement about when the Romans used coal and when coal became an important energy resource in Britain.

Evaluate the article

The articles content is relevant to the topic. The content is not up-to-date. There are newer publications that provide additional insight into lignin degradation than what the article currently cites. There is content missing and content that does not belong, for instance, the seeming contradiction in the articles history section. The article deals poorly with one of Wikipedia's Equity gaps. It does not address topics related to historically underrepresented populations. The article is neutral, but there may be claims that appear heavily biased toward a particular position. The sources are thorough, but the sources may not be current. The sources do not include historically marginalized people. There may be better source available, such as peer-reviewed articles in place of random websites. For instance:

1. "Dethroning King Coal – How a Once Dominant Fuel Source is Falling Rapidly from Favour". Resilience. 24 January 2020. Retrieved 8 February 2020.

The article is concise, well-written and easy to read and is well organized. The article does include images that enhance the understanding of the topic and they are well captioned and adhere to Wikipedia's copyright regulations. The images could be laid out in a more visual appealing manner. the talk discussion page has friendly conversations about trying to improve the article's content, with some debates and suggestions on things that need updating. The article has been rated as C-Class by WikiProject Vital Articles. The articles strengths are it is concise, well-written, has good flow, and contains content relevant to the topic. The article can be improved by adding more up-to-date information and more peer reviewed publications as sources. The article is well-developed and is only missing content related to its uses by historically marginalized people and the most current publications on the topic. suggestions for additional citations: https://www.iea.org/reports/coal-2019#executive-summary

  Yang, Ghatge, S., & Hur, H.-G. (2023). Improvement of thermoalkaliphilic laccase (CtLac) by a directed evolution and application to lignin degradation. Applied Microbiology and Biotechnology, 107(1), 273–286. https://doi.org/10.1007/s00253-022-12311-4

  Zhang, Yao, Y., Deng, J., Zhang, J.-L., Qiu, Y., Li, G., & Liu, J. (2022). Hydrogen production via anaerobic digestion of coal modified by white-rot fungi and its application benefits analysis. Renewable & Sustainable Energy Reviews, 157, 112091–. https://doi.org/10.1016/j.rser.2022.112091~~~~ Hylaversicolor (talk) 18:11, 3 February 2023 (UTC)

Thanks for that evaluation. I am not an expert but I thought from the talk page discussion that the lignin degradation thing had been sorted. If I misunderstood please let me know.

You raise an interesting point about the lack of info on marginalized people. Perhaps that info would be best put in the “Coal in country X” or “Coal mining in country X” articles. For example Coal mining in Pakistan just has one uncited sentence saying that (in Duki region) “More than 50% of the labor is from Afghanistan.” but nothing about the miners in Thar, which is where I understand they plan to built lots more coal power plants.

Feel free to edit any of the articles Chidgk1 (talk) 17:29, 26 February 2023 (UTC)