China News Network, Nanjing, April 2 (Yang Yanci) The science fiction movie "Wandering Earth" shows the rapid aging and expansion of the sun in the future, and the world is full of frozen scenes. In the history of the earth, similar extreme climate events have occurred many times. How long does it take from extinction to restoration of normal forest vegetation, lakes and oceans? Researchers from China have come up with a new idea.
The Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences released a new research result on the 2nd: The research team of the Institute found that after the end of the Permian era ’s largest extinction, the lake and forest ecology It can take up to 10 million years for the system to recover significantly.
Field photo of Tongchuan area. Photo courtesy of Nanguo
It is understood that the end of the Permian biodiversity event caused a serious marine and terrestrial ecosystem crisis, and about 75% of terrestrial biological species disappeared.
How long does it take for terrestrial ecosystems to recover after the mass extinction? Recently, the latest research from the research team of the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences found that lakes and forest ecosystems may take up to 10 million years to recover significantly after the end of the Permian mass extinction.
Related results were recently published online in a well-known international journal "Geology".
Under the guidance of Researcher Wang Bo and Researcher Zhang Haichun, Dr. Zhao Xiangdong and Dr. Zheng Dayan of the "Research Team on the Origin and Early Evolution of Modern Terrestrial Ecosystems" cooperated with engineers from Changqing Oilfield Xie Guwei, etc. The lacustrine sedimentary stratum has been systematically studied, and it is proposed that the lake ecosystem showed obvious recovery in the middle of the Middle Triassic.
Wang Bo said that he had speculated early that "recovery" would take 15 million years. This study found that marine ecosystems and lake ecosystems are closely linked, and the recovery period begins almost simultaneously. Although the recovery of the two is very slow, it is "completed" about 5 million years earlier than previously expected.
At the same time, the study horizon is also an important oil-producing layer in Changqing Oilfield. The results of isotope chronology and stratigraphy also provide new dating and fossil evidence for fine-time stratigraphic comparison and oil and gas resource exploration.
Overall, the research results show that the recovery of complex lake ecosystems coincides with the end of the "missing period of coal seams", suggesting that lakes and forest ecosystems may be closely linked through biological, physical, and chemical interactions. In short, lakes and forest ecosystems may take up to 10 million years to recover significantly, much longer than the restoration of plant communities inferred from pollen data.
Wang Bo believes that the hot climate of the Early Triassic will limit the dissolved oxygen content in the lake, which will hinder the recovery of the ecosystem. However, the large increase in carbon burial in the Anny period ocean may lead to a decrease in atmospheric CO2 content and global cooling, thereby improving the ecological conditions of the lake.
In addition, volcanic ash brings rich nutrients to the lake, which may significantly increase the primary productivity of ancient lakes in the Ordos Basin. Therefore, global temperature reduction and volcanic ash nutrient input may jointly promote the prosperity of ancient lake ecosystems in the Ordos Basin.
Relevant research work was jointly funded by the Chinese Academy of Sciences and the National Natural Science Foundation of China. (Finish)