The term biosphere is not unfamiliar to all the scientists here.

The Earth is a huge biosphere, from 10,000 meters above sea level to 11,000 meters deep in the ocean. The Earth's biosphere is mainly composed of three parts: living matter, biogenerated matter and biologically inert matter. Among them, living matter can be divided into three categories, namely producers, consumers and decomposers.

The producer, also known as the green plant, converts carbon dioxide into organic matter through photosynthesis and releases oxygen, and the producer and consumer breathe in oxygen and reconvert the organic matter into carbon dioxide, which is the carbon cycle.

The Earth's biosphere has a large volume, high biodiversity, complex trophic structure, and strong self-regulation ability, so the concentration of carbon dioxide and oxygen in the Earth's atmosphere has always maintained a balanced state.

It sounds simple, you just need to maintain a balance of carbon and oxygen. However, in the complex and huge system association, every breeze may be indispensable for life, and human beings have done many experiments on the artificial ecosystem, but without exception, all of them ended in failure!

In the 90s of the 20th century, the United States once built an artificial closed ecosystem, called "Biosphere 2", in which eight researchers conducted experiments for 21 months.

They conduct ecological and environmental research in a closed state, helping humans understand how the earth works, and studying the conditions under which the earth's ecological environment is simulated.

However, after 21 months, the experiment failed because the atmospheric composition of Biosphere 2's oxygen to carbon dioxide did not equilibrium on its own, and most plants and animals were unable to grow or reproduce normally, and the rate of extinction was even faster than expected. Cockroaches and ants are full of offspring, and to make matters worse, their oxygen levels have dropped from 21 percent to 14 percent, which could be life-threatening if humans lived in them.

Scientists thought they had found the cause of the failure, and then Biosphere 2 welcomed a second group of residents, but only half a month later, the experiment failed again because of the accumulation of laughing gas.

Since then, people have learned that the Earth is still the only home of mankind.

The existence of the lunar base depends on the continuous supply of the earth, and it cannot survive alone.

"Now, we have to build a real ecosystem!" Dr. Roman exclaimed, "Maybe it's simpler, just carbon neutral." ”

He frowned, with the technology that humans have, can they really build a completely balanced biosphere? Moreover, once this experiment is started, it must be successful, and if it fails, it is the extinction of the entire race.

"No, no, Roman, you're thinking too much, it's too complicated!" A female scientist stood up and said loudly, "We don't have that much time to think about that right now." ”

"As for the carbon dioxide you mentioned, we can make carbon dioxide from methane and carbonates on the moon. The priority is to solve this food crisis and nothing else! ”、

"Oxygen and water, don't think about it for now. We still have it in stock. ”

A group of scientists quarreled and began to calculate the feasibility of various options in order to arrive at the best possible result.

Yu Yifeng listened while sorting out the relevant ideas, and slowly, his heart began to heat up, hope, there is hope!

After all, there are 50,000 people carefully selected from the earth, among which there are the best scientists, the most skilled technicians, and the most experienced engineers...... The productivity of the lunar base is comparable to that of a small country.

The mineral resources here are also much more abundant than expected. The location of the lunar base was chosen here not only because there are alien spacecraft here, but more importantly, there are nearly 220 million tons of ice deep underground!

Do not think that there is no water on the moon, they are just hidden deep in the earth's crust in the form of ice. 220 million tons of ice is not much compared to the water resources on the earth, but it can already be regarded as a rich treasure.

Human survival is inseparable from water, but water cannot be compressed, and transportation is very troublesome. With such a large number of hundreds of millions of tons, it is almost impossible to transport it from the earth, you must know that the carrying capacity of the Victory is only 500 tons! Therefore, these ice mines become the best resource.

Due to the ice mines underground, there is no shortage of water resources for the time being, and although nearly half of the ice has been mined over the years, there are at least 100 million tons of reserves! Save a little, enough for human beings to use for decades. Even if it is used up, humans can still use the minerals and rocks under the ground to decompose crystal water, but it is a little more troublesome.

As for oxygen, some of it is transported from the earth, and some of it is obtained by photosynthesis of plants, but most of it is obtained by electrolyzing minerals. For example, the electrolysis of metal oxides, or the electrolysis of water, can obtain oxygen.

The amount of oxygen required by the entire base is about 15,000 tons a year, which is not high, and only 17,000 tons of water need to be electrolyzed. So the problem of oxygen is also solved.

As for carbon dioxide, it can be obtained by breaking down carbonates or by burning methane, which is abundant in solid methane at the polar regions of the moon, near the base. However, carbonate near the surface is very scarce, and can only be excavated deep underground, and the amount of work is large, and if you burn methane, some new problems arise, and the combustion of methane requires an oxidant, that is, oxygen!

However, it takes a lot of energy to produce oxygen, so it is necessary to increase the energy output...... Solar energy alone is not enough, the easiest way is to increase the development of uranium resources and build nuclear power plants!

In the end, the stall was getting bigger and bigger, and there were more and more aspects involved, and it felt that nothing was enough, and everything needed to be rebuilt, and Yu Yifeng was already a little confused.

He is not an orthodox scientist after all, he just writes down some numbers and considers whether it is feasible, and as for other details, it is up to these scientists to consider.

"You guys are overdrawing the future!" Roman roared as he put his hands behind his head and rubbed his hair deeply. Food production is now being the main concern, while the idea of building ecosystems has been put on hold for the time being.

"Our water resources are also limited......" He wanted to say something, but was pulled by a person, Yuriko, his adopted daughter.

Yuriko whispered, "Father, we always have to get over the difficulties in front of us before we can think further, don't we?" ”

"yes, alas...... You're right, a complete ecosystem can't be done overnight. Roman smiled bitterly.

At this time, Yu Yifeng suddenly had a flash of inspiration and thought of an idea of odd seconds. He jumped up from his position and said, "Everyone, everyone! Listen to me, why don't we move to an alien spaceship? ”

"Originally, there was no major development of the alien spacecraft because the government wanted to keep the spacecraft and the secret of Perfection. Now that the secret is known, why abandon it? ”

"Whether it's security or anything else, it's a very good choice!"

The crowd suddenly fell silent, talking to each other and whispering about the feasibility of the plan.

"I agree!" A male voice came from behind, it was Chief Physicist Felix, "If everyone moves into an alien spaceship, we can empty the surface and plant all the plants, which will save a lot of time!" ”