User:Paul JCW/sandbox

= Article Evaluation =

Evaluating Content
The content of this article is mainly about the explanation of biotic cycles (production and consumption) and abiotic cycles (sources and sinks) of hydrogen-containing compounds. Moreover, two extensive parts ('the relevance for the global climate' and 'implications for astrobiology') are introduced as well. From my perspective, I think the section on 'the relevance for the global climate' is too short and should be improved by adding more reactions and figures. Overall, I think everything in the article is relevant to the article topic and nothing distracted me. The information is not up-to-date and should be improved. The scientific information is presented clearly, accurately, and without jargon. The article does link to other Wikipedia articles for related topics, but I think it could be improved. For example, the link to the 'microbial metabolisms' should be added in this article.

Evaluating Tone
The tone of the article is neutral and unbiased. Each section is short and gives scientific explanations without any position. And no viewpoints appear to be overrepresented or underrepresented.

Evaluating Sources
In terms of the 17th reference (Hydrogen Metabolism and the Evolution of Biological Respiration), the website's certificate was expired. So this link may not work. To sum up, the sources strongly support the claims in the article, and each fact is referenced with an appropriate and reliable reference. Meanwhile, the references come from reliable and neutral journal papers.

Evaluating Content
The content of this article is excellent, which gives a detailed overview of the carbon cycle on the Earth. The article has an elaborate explanation of the main components of carbon cycles such as the atmosphere, terrestrial biosphere, ocean, and geosphere. Moreover, the article introduces other relevant topics about the carbon cycle, for example, the deep carbon cycle, human influence on the carbon cycle, and so on. The figure for the terrestrial carbon in the water cycle is really beautiful. Thus, the information is sufficient for this topic. Overall, everything in the article is relevant to the article topic and nothing distracted me. The information is up-to-date and couldn't find out that anything could be added or improved. The scientific information is presented clearly, accurately, and without jargon, and the article does link to other Wikipedia articles for related topics.

Evaluating Tone
The article has a neutral tone. And there is no claim that appears heavily biased toward a particular position. What's more, no viewpoints are overrepresented, or underrepresented.

Evaluating Sources
In the section on 'Terrestrial biosphere', I didn't see the source for the sentence 'In 2008, the global total of CO2 released by soil respiration was roughly 98 billion tonnes, about 3 times more carbon than humans are now putting into the atmosphere each year by burning fossil fuel (this does not represent a net transfer of carbon from soil to the atmosphere, as the respiration is largely offset by inputs to soil carbon)', which should be improved. Moreover, the links for the 17th reference (Many Planets, One Earth // Section 4: Carbon Cycling and Earth's Climate) show 'Page Not Found', which needs to be fixed. Generally, most facts are referenced with an appropriate and reliable reference. And the information comes from scientific journal papers or the NOAA and NASA websites, which are unbiased.

Evaluating Content
The content of this article discussed the common processes of the nitrogen cycle with detailed explanations such as nitrification, denitrification, ammonification, and so on. The other discussions relevant to the nitrogen cycle (i.e., human influences on the nitrogen cycle, consequence of human modification of the nitrogen cycle) are presented, which are interesting to the reader. From my perspective, I was confused about why the marine nitrogen cycle has to be discussed separately. It would be better if this could be explained. Overall, everything in the article is relevant to the article's topic. The information is up-to-date and I think it would be better to add some chemical reactions in the processes of the nitrogen cycle. The scientific information is presented clearly, accurately, and without jargon, and the article does link to other Wikipedia articles for related topics.

Evaluating Tone
The tone of the article is neutral and no claim is heavily biased toward a particular position. The article is scientific and objective, no viewpoints are overrepresented, or underrepresented.

Evaluating Sources
Mostly the data, statements, chemical reactions, and figures have annotated sources. But in the section on 'Human influences on the nitrogen cycle', I didn't see the source for the sentence 'The very high temperature of lightning naturally produces small amounts of NOx, NH3, and HNO3, but high-temperature combustion has contributed to a 6- or 7-fold increase in the flux of NOx to the atmosphere. Its production is a function of combustion temperature - the higher the temperature, the more NOx is produced', which should be improved. The links work well for each citation and the sources support the claims in the article. Generally, most facts are referenced with an appropriate and reliable reference. And the information comes from scientific journal papers or websites, which are unbiased.