Signs indicate life on earth is facing a new mass extinction

Carboniferous-Permian geological history is the most critical period

Carboniferous and Permian is the final two Paleozoic century, representatives from 354 million years ago to 252 million years ago the historical stage. Carboniferous-Permian the lithosphere, hydrosphere, atmosphere and biosphere evolution are in a very crucial stage of evolution. Geological history of north-south pole of the pan-continent during this period due to large-scale activities to form plate; Carboniferous-Permian also occurred early largest glacier; Carboniferous history of the Earth is also the largest-scale carbon burial period, the rest of the world at present a large number of coal mining resources in that period formed.

Carboniferous-Permian was a world full of vigor, biological species very busy, biodiversity than any time before, in a fairly long period of time to maintain stability and prosperity in the forests there were even two-meter-long wings of dragonflies. Marine life during this period is very busy. However, in the late Permian geological period, the largest of biological extinction events.

CAS Nanjing Institute of Geology and Paleontology researcher Shen Shuzhong in an interview with reporters, said that attending the "16th International Carboniferous-Permian geological conference," Chinese and foreign scientists, in the Carboniferous-Permian biological evolution and the environment with the theme around the Carboniferous-Permian JI biota and climate change, isotope geochemistry and geology biology, sedimentology and stratigraphy, high-resolution integrated biological stratigraphy, the end of the Permian mass extinction and environmental background, "gold nail" with the global comparison, the Earth time system of extensive discussions and exchange views.

In recent years, China end of the Permian mass extinction in the sea and continental strata record, as reflected in the model, the Carboniferous-Permian flora and ancient climate evolution of the Carboniferous-Permian the "gold nail" and high-resolution stratigraphic correlation, Quantitative paleontology and stratigraphy research by foreign experts to the concerns . By the late 0800-gan led by the International Working Group to establish a China Lopingian represented by international standards, the Upper Permian most two "golden nails" were nailed on Changxing Meishan in Zhejiang and Guangxi in Penglai profile guests around Meishan section Zhejiang end of the Permian mass extinction research has made the world attention achievements.

As the Carboniferous-Permian, and the importance of research achievements in recent years, the Nanjing Institute of Geology and Paleontology of the Late Paleozoic group formed by the State Natural Science Fund Committee, the outstanding innovation groups, groups several members of the international Carboniferous and Permian stratigraphy branch of the Election Committee members, international Carboniferous-Permian related research played a substantial role.

Super extinction

Extinction of biological taxa is unable to adapt to environmental changes and to survive, life is the history of endless natural events, competition among species, and natural selection led to the extinction of the conventional rate of extinction. But some large numbers of biological groups in a short time away, but the whole world, and lead to a sudden cluster of extinction, paleontologists have been called mass extinction. Since Precambrian biological outbreak since there were five major extinctions, which occurred in ancient at the turn of the Mesozoic, that is the end of the Permian mass extinction, the largest of biological development of the most profound impact.

CAS Nanjing Institute of Geology and Paleontology 0800-gan academicians wrote : "This is a super extinction, the diversity of marine life down to below one-tenth of the original ecosystem has been completely updated, as the Paleozoic and Mesozoic pillar, and all other extinctions are far from it and Great extinction, nor biological evolution process in such a major turning point. "

Long time, the mystery of the extinction of dinosaurs has been featured, in fact, since the late 18th century, scientists around the world have not only studied the extinction of dinosaurs true, the first study to or after the extinction of dinosaurs to extinction of other events. Although the extinction of dinosaurs to the theory of evolution had a tremendous impact, but compared to those living in the Carboniferous-Permian biological, the dinosaur extinction event is not the most "tragic".

"Geological period, the largest-scale extinction events occurred in the late Permian, the statistics show that on the Earth, and more than 90% of marine species and 75% of land species in all this period of extinction." Shen Shuzhong said.

The end of the Permian, corals, dragonflies calcareous sponges, brachiopods, trilobites, such as fixing the sea, feeding the passive category of extinction or have a large number of abatement, reef ecosystem collapse, burying carbon stop. The terrestrial species, the Carboniferous-Permian flora ferns mainly to the coastal swamp forest zone formation, but to the rapid demise of the late Permian, miniature plants to replace. Four-footed vertebrate animals in there Late Carboniferous, Permian quickly become the most representative of terrestrial animals, in the Late Permian who had up to 5 ~ 6 meters, like mammals reptiles -- beast Hole. But by the end of the Permian, 63% of the four-footed rapid extinction of the Branch.

Mystery extinction

Scientists from the current available information, the end of the Permian mass extinction in a very short period of time of rapid, then what is destroying the Permian prosperous populations?

The current mass extinction due to a combination of different explanations, no one recognized the unanimous view. A more generally accepted view that the late Permian and may frequent eruption of the volcano. Geological evidence shows that the late Permian mass volcanic eruptions, the Earth's surface at that time there were several volcanic eruptions, including Siberia and the south China region. Volcanic eruptions have large amounts of toxic gas, the release of large amounts of carbon dioxide, the greenhouse gas, a result of plant and animal extinction.

Research has also found that the mass extinction strata containing sulfur rich minerals, suggesting volcanic eruptions releasing large amounts of hydrogen sulfide gas, followed by acid rain, pollution of the ancient oceans, causing massive extinction of marine life. In addition, some people think the end of the Permian there was similar to the end of the Cretaceous celestial impact, the impact sites may be located in Western Australia, causing instantaneous death of a large number of biological, but such reasoning was lack of sufficient evidence.

Currently, scientists on this important historical events are the causes, mechanisms, and the environment at the time, the whole process of renewal time is not very clear, all these comments have been no sufficient evidence to prove that the end of the Permian mass extinction reason is a mystery. The well-known American scientist Douglas Irvine put the end of the Permian mass extinction described as "Oriental Express on the murder case," that there are many different factors working together caused the end of the Permian mass extinction events.

Mankind is witnessing a new mass extinction?

Studies have shown : mass extinction, without exception, by the Global Environment arising from the severe deterioration. In recent years, due to increased human activities on the ecological environment has continued to worsen, endangered and extinct species growing to the global biodiversity poses a serious consequences, as well as a threat to the survival of mankind itself. This has caused people to doubt the planet is facing a "sixth mass extinction events?"

The recently published in "Nature" magazine says the article, 50 years later, more than 100 million land-based biological disappear from the planet. The International Federation of natural resources to protect the "2004 Global Species investigation" revealed : a global Earth more than 15,000 species of endangered species, the rate of extinction than any time in the past. Scientists have discovered that human activities causing the extinction of species extinction than natural high-speed 1,000 times per hour, have a species to extinction.

According to a conservative estimate that the current annual extinction on Earth about 30,000 species, such prehistoric extinction rate than normal (annual extinction of about three species), nearly 10,000 times faster, far more than any large prehistoric extinctions. Five major extinction by prehistoric strength and size, there are scholars who believe the current biosphere has entered a "sixth extinction" period and that the only real modern human face mass extinction process. Biological and environmental development not only aroused extensive public concern, has become a hot research scientists.

Carboniferous to Permian from both biological evolution and climate conditions at that time and so on are all at a relatively stable stage, but a time of the late Permian, the environment has been deteriorating. Such sudden changes What is the mechanism? Now the scientific community is unclear. Some scientists have proposed that the Earth's ecological environment and the climate system, such as the rapid reduction of biodiversity, acid rain frequency, the overall deterioration of the environment, the greenhouse effect, etc., in the late Permian and environmental conditions comparable to a certain extent, it is necessary for us to attach great importance to mankind.

With the lives of the Earth, and biological environment has become a mutual restraint, mutual promotion of the Community. The Earth's environment to create a life, to promote the development of life-changing social environment. The geological period some major life changes directly with the major global changes linked, but significant period of global change biology and the environment appear most clearly period. All the signs indicate that the earth is facing today a new twist to the Earth, environmental degradation, biodiversity dramatic reduction is a serious threat to human survival and sustainable development of natural resources. The mass extinction of the study is to explore not only the extinction model, but more importantly out of our own care. Mankind is witnessing.