Changes in the Asian monsoon have affected emissions of methane from the Tibetan Plateau over the last 6,000 years, finds a new paper.
The concentration of methane in the atmosphere has more than doubled over the past century, though it is very short lived compared to carbon dioxide and hasn't been considered much of a factor in climate change. Factors in methane levels include leaks from gas wells, increased rice cultivation and ruminant animals in the dairy and meat industry. It could also be caused partly by climate change feedbacks on natural processes, but that remains the subject of intense investigation.
The results focus on a single wetland from the Tibetan Plateau that experienced strong climate variations over the past 6,000 years. They show that during relatively dry intervals, the biomass of methane-producing microorganisms decreased while methane-consuming microorganisms apparently became more efficient. The combined result would have been less methane emission to the atmosphere.
The Tibetan Plateau experienced strong climate variations over the past six thousand years. Credit: University of Bristol
According to project leader and Director of the University of Bristol Cabot Institute Professor Rich Pancost, "What we have done is connect the dots, providing strong evidence for previous researchers’ inferences. In modern settings, methane emissions from dryer settings are generally low. Consequently, previous researchers have speculated that as the Asian monsoon became weaker over the past six thousand years, methane emissions also decreased. Here, we show that this is exactly what happened to this peatland on the Tibetan Plateau."
The authors used a combination of chemical tools to reconstruct the past changes in microbial populations. First author Yanhong Zheng said, "All organisms have cell membranes but the molecules that comprise those membranes differ, especially for microorganisms; if these molecules are preserved in soils or sediments, they act as molecular fossils – or biomarkers – for those organisms in the past. We can then quantify them and that gives insight into ancient microbial communities."
The authors focused on archaeol, a compound that likely derives from methanogens (or methane-producing organisms) in these settings. During a dry interval from six to four thousand years ago, its concentration decreased by about 50 per cent, suggesting that the methane producing community became much smaller, probably because these organisms favor wet habitats.
Pancost added, "This is only a single site, but our study has wider implication for how these systems work. The dry interval we studied arose from large scale changes in atmospheric circulation patterns, and just as past changes impacted methane emissions, so will future climate change."
Citation: Yanhong Zheng, Joy S. Singarayer, Peng Cheng, Zhao Liu, Xuefeng Yu, Paul J. Valdes, Richard D. Pancost, 'Holocene variations in peatland methane cycling associated with the Asian summer monsoon system', Nature Communications
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Top Secret: On Confidentiality On Scientific Issues, Across The Ring And Across The Bedroom
- Would New Planet X Clear Its Orbit? - And Any Better Name Than "Planet Nine"?
- The Mystery Of The Red Sea
- The Greenhouse Effect Fallacy
- Stop Using BMI To Determine Health
- Why Diamonds Are More Of A Scientific Miracle Than You Think
- From Allergens To Anodes: Pollen Derived Battery Electrodes
- "So there is no why like Bob Fletcher or as some people say you can already see it on Russian news..."
- "Hi Joe, yes the thing is - all that is fine, it's logical from your point of view. And whatever..."
- " Like I asked David Brin: Who are the ones who are actually insane? Certainly it is NOT the skeptics..."
- "https://www.youtube.com/watch?v=nVyV4L072jY So then what is going on in this video? Also what is..."
- "Just curious, When was the last time you (the author) generated a mathematical model? On what?..."
- Florida Declares Zika Virus State of Emergency
- Indonesia’s Many Human Physical Deformities: A Closer Look
- Spinal ‘Column’: Love for Hunchback Dog, Breakthrough for 8-Yr-Old Girl
- BMI is Bologna
- Energy Drinks: The Dose Makes the Poison
- California’s Prop 65: Bad For Public Acceptance Of Science, About To Get Worse
- Cambridge researcher develops smartphone app to map Swiss-German dialects
- Studies link healthy workforces to positive stock market performance
- Pioneering discovery leads to potential preventive treatment for sudden cardiac death
- Online shopping might not be as green as we thought
- Gene family turns cancer cells into aggressive stem cells that keep growing