According to the magazine "Nature", the human impact on the environment will lead the planet to the point of change. Last time it was 12 000 years ago. About it says Laure Nuala "Libеration" (France).

Usually in Hollywood the end of the world is in the form of a giant meteorite, disaster or nuclear war. The form that is presented in a study published in the scientific journal Nature (1), have resembled a human hand. Not to the one that presses the red button, but one that is comprehensive way all the people that are putting pressure on ecosystems.

The article, written in June multidisciplinary international team consisting of two dozen scientists, says plainly: we leap closer to the inevitable and irreversible collapse of the ecosystems on which they depend for human civilization. If they are destroyed, our future will be extremely vague. Some of the researchers admit that their "terrifying" own conclusions.

The unknown. The biosphere on the threshold of a state change, a kind of caving into the unknown. Several phenomena are superimposed on each other: the accelerated loss of biodiversity, increased cases of climate disasters, rapid change of production flows and expenditure of energy... "When changing the mode of functioning of the ecosystem, you may receive what is called the status explains Bruno David (Bruno David) from the laboratory of biogenous CNRS (national center for scientific research) in Dijon. Now we are on the verge of one of these dramatic changes".

In past crises radical changes were called biogeochemistry of the Earth, volcanic eruptions or giant meteorites. This time the researchers called the reason of man. In the opinion of the group of paleoecology Tony Barnosky (Tony Barnosky), who coordinated the work of researchers, we "influential enough to change the conditions of life on Earth, radically changing ecosystems and the local climate. "Simply put, the state change is accelerated by human behavior and its needs," said Steve carpenter (Steve Carpenter) from the University of Wisconsin.

These state changes can be small and local, limited to the borders of the lake, pond... "we understand Them quite well. But the biggest point of change has not been determined yet," explains Martin Schaeffer (Marten Scheffer), a pioneer of research in this area. Importantly, Schaeffer not sure what to expect just one point of change. "In the past, there have been enormous point change, and they have now. The difference is that today we see them coming..."

A state change causes two things: the effect of the threshold or mass effect. First, it is difficult to predict, as the critical threshold is reached gradually, and we never know in advance how damaging it is. But mass effect is never unexpected, for example, in the case of destruction of the forest by a bulldozer. But people change the composition of local species and ecosystem functions, causing changes on a small scale, which in combination with each other, forming a chain of events leading to more global change.

Ricochet. In the opinion of the team Barnoski, the cause of this problem is first of all a change of type of land use, and only then - climate change. During its history, humanity has changed 43% of the land, destroying forest to develop in their place of intensive agriculture, eliminating the capacity of the environment to build on them in the city. "This rebound has affected almost all of the remaining terrestrial surface: a third of drinking water is diverted for human use, and 20% of what makes the earth, goes to one of our needs," explains Barnoski.

On the planet this is not the first time. Changes occurred on coral reefs and in the Sahara desert, which was a fertile area with lush vegetation another 5 500 years ago. But what says the team from Berkeley, will change very sharp: the worst changes can occur in this century, perhaps up to 2050. "The evidence is quite clear. We cannot ignore some of the biological realities", - insists Barnoski. Usually state changes are developing for thousands, even millions of years. For 500 million years, the Earth has experienced five major crises that led to five mass extinctions on earth. The last time was 65 million years ago and caused the death of the dinosaurs. Another example: 12 000 years ago, the transition from the ice age to interglacial lasted a thousand years. Since then, the climate in a global sense of stable, which allowed the person to develop to such an extent that he was able to go to the moon.

What happens next? Perhaps we will see a mass movement of species on an uninhabited part of the Earth, an enormous loss of biodiversity, the emergence of new biotopes and - why not - tropical forests in Antarctica. "The last time this happened 12,000 years ago: disappeared half mammals weighing more than 50 kg," says Barnoski. "State changes are fraught with a lot of surprises, but we know about them enough to understand that the world will be very different from what it was in the last 11,000 years, he warns. - And we are on Earth 7 billion, will probably feel it myself".

(1) "Approaching a state-shift in Earth's biosphere"