In fact, Mo Qingyan also knew how important it was to have a greenhouse that could produce food in the post-apocalyptic environment, but her family's shelter was built when the house was built, and the greenhouse was not considered at that time, but the basement was designed as a bar.

This also led to the fact that Mo Qingyan's shelter was not self-sustaining in terms of food.

In the short term, of course, this is not a problem, whether it is exchanging supplies with others, or obtaining food in other ways, it can be sustained.

Even because the underground space is sufficient, Mo Qingyan has a lot of materials in reserve, enough for her, Mo Qingxin and Ding Ning to eat for two years.

If it's just a nuclear war or some other apocalyptic disaster, a year or two is enough time for them to wait for the post-disaster reconstruction or the rescue of the search and rescue team.

But now we need to face a hundred years of extreme cold nights, the surface of the earth will be a permafrost environment for a hundred years, not suitable for any crops at all, and almost 99% of human food production will be completely reimbursed.

In such a situation, all one can count on is a stockpile of pre-disaster supplies and a plantation greenhouse built in the shelter that is underground, less affected by temperatures.

Chen Xin's side may not know the situation because he is far away from the city, but Mo Qingyan knows some about the situation because of the city government shelter and shopping center shelter next to the city, and now the shelters in the city have begun to control the use of materials.

Although the main source of food is still the food stored before the disaster, it has begun to mix the food with mushrooms grown in greenhouses and rats.

In the Yan country, mushroom cultivation technology is quite mature, which is why the government chose to use mushrooms as the main food source for post-disaster shelters.

As the main source of food that can be obtained in the current environment, if the management is reasonable, in a suitable environment, the planting area of 100 square meters adopts three-dimensional cultivation of five layers, and the yield can reach 75,000 catties a year even if the most conservative one square meter produces 30 catties.

This is not a low yield, but if they want to ensure the food supply of a shelter, although it is difficult to build a greenhouse in a small shelter, it is not a big problem for them to ensure food supply without a large planting area.

It's like Chen Xin's refuge, a 100-square-meter planting greenhouse, if you plant all mushrooms, it is enough for Chen Xin to eat to death alone, and the excess yield can be used to make mushroom wine to drown himself.

But for large shelters, the problem is more serious, and the larger the shelter, the more serious the problem.

Because the more people there are, the more food they need, and the larger the greenhouse area they need.

After all, at first glance, it seems that 100 square meters can produce more than 70,000 catties of food a year, but the city has a resident population of 300,000, and thanks to the Yanguo government's policy of "not abandoning a person" before the disaster, at least more than ninety percent of the people were able to enter the shelter and survive.

Based on the calculation that one person consumes one ton of food a year, 270,000 people need at least 360,000 square meters of mushroom cultivation area to meet the consumption.

Since the surface is no longer able to grow any crops, all food sources are underground greenhouses, but there is obviously no such large place in the shelter to arrange the planting greenhouses.

The 360,000 square meters are 3,600 acres, 540 acres, and 36 hectares, which is equivalent to the area of half of the Forbidden City, 1.7 bird's nests, and 51.4 standard football fields.

Such a large area, if it was before the disaster, of course, it is not a big deal, not counting the area of rural cultivated land, just the labor reform farms near the city have 36,500 mu of cultivated land, and grain output is not a problem at all.

As for the need to repair a planting greenhouse or something, if you want to repair it on the surface before the disaster, such a large area of planting greenhouse is nothing more than a matter of money, and there will be no construction difficulties.

But in the last days when disaster has struck, because of the severe cold, it is no longer possible to build greenhouses on the surface, and if you want to ensure enough food production, you can only dig enough space underground.

And the time required to dig out such a large area of underground space is not short.

Even if the evacuation shelters had enough manpower and enough tools to dig up such a large space, it would be a very big project.

In other words, food shortages are a problem that shelters will inevitably face in the future, if nothing else.

Fortunately, the end of the world has just begun, and the major shelters have enough material reserves to support them for a long time.

This is a prime time for shelters, and it is up to them to dig up enough greenhouses to grow during this time if they can cope with the food crisis that will arise.

Therefore, it is foreseeable that food will become the most sought-after rigid need in the future, and being able to ensure that you have a stable supply of food that you can obtain has become the top priority if you want to survive in this last world.

Whether it is Chen Xin, Mo Qingyan, or the people in other shelters, if they want to survive in this apocalypse, they must first solve this problem.

Fortunately, for Chen Xin, with systematic help, food is no longer a problem for him.

"Okay, with Ah Lan's help, this time Long Niang's problem there can be regarded as solved." Chen Xin looked at Mo Qingyan and said to her with a smile in his tone: "Then you only need to vacate the wine cellar and transform it into a greenhouse." ”

"Hmph, I've vacated the cellar, and you can remember my collections, right? I tell you, if you want my wine, you can exchange it for good things! Mo Qingyan snorted at Chen Xin.

Looking at Mo Qingyan's appearance, Chen Xin suddenly laughed: "Don't worry, I won't let you down!" ”

Regarding the bickering conversation between Chen Xin and Mo Qingyan, Qin Lan just watched from the sidelines, and when the two finished speaking, she said: "If the two of you finish chatting, shouldn't you go and get the food that Ah Xin promised us to give the SWAT team?" ”

Although Chen Xin exchanged supplies with Uncle Ding in the name of Mo Qingyan, both Uncle Ding and Chen Xin understood that the two sides of the transaction were Chen Xin himself and the SWAT team.

After all, although Uncle Ding is the captain of the SWAT team, he can't take out so many supplies himself, and he can't bring so many vegetables to eat alone, so it is inevitable to collect materials in the name of the SWAT team and exchange the vegetables to improve the food for the SWAT team.

So Qin Lan didn't have a problem saying this at all.

Facing Qin Lan's urging, Chen Xin laughed and led them to his planting greenhouse: "Don't worry, the vegetables are all ripe, and I was harvesting before you came." ”