First of all, potato cultivation has very strict soil requirements. Only soil with deep soil, loose structure, good drainage and aeration and rich in organic matter is the most suitable environment for potato growth.
And that's not all. The growth and development of potatoes requires more than ten kinds of nutrients, and the demand for fertilizers is quite large.
If potatoes are continuously planted in a piece of land, the soil fertility will be greatly reduced due to the absorption of soil fertility by potatoes. The yield of the plot under continuous cropping will be reduced in the second year, and the quality of tubers will also be reduced, especially diseases, insects, and weeds will occur. become more serious.
Even the protagonist of "The Martian" reused the vacuum-dried excrement saved by previous astronauts when planting potatoes on Mars, fermented it into manure, and then started planting potatoes.
More importantly, the stems and leaves of potato plants are poisonous, and even the potatoes themselves are poisonous.
Potatoes mainly contain solanine and chaetomycin. Generally, the toxins will decompose when heated to 170°C.
Although artificially cultivated potatoes are not highly toxic, if the amount of consumption exceeds 1.4 kilograms, the accumulation of toxicity in the body will still produce a toxic reaction.
As for the solanine produced after potatoes sprout, it is a toxin that can cause severe poisoning if ingested at 0.2%.
Especially for pregnant women, if they eat potatoes for a long time, the alkaloids contained in them may accumulate in the body and cause fetal malformations.
Before the disaster, of course, everyone could eat and plant potatoes at will. After all, potatoes are indeed abundant, and as long as you pay attention to planting rotation and fertilization when planting, you can avoid many problems that arise during planting.
But the toxins in potatoes are an unavoidable problem. After all, the end of the world is not like before the disaster. People can choose from a wide variety of foods and eat many different foods, and the abundant supply of materials allows people to always eat fresh food. potatoes, greatly reducing the risk of poisoning.
But in the end of the world, there are no such conditions. The underground land resources are limited, and there is basically only one kind of staple food to grow.
And this will cause people to eat potatoes for a long time.
In addition, it is definitely not possible to grow and eat the potatoes in the shelter. It is foreseeable that the harvested potatoes will become moldy and sprout during storage.
Before the disaster, this would have been thrown away, and no one would eat the sprouted potatoes.
But in the end of the world, these are all important food reserves. Rats, cockroaches, and earthworms are all used to eat them. How many spoiled potatoes? As long as it doesn't kill anyone, you can eat it cooked!
So at this time, toxins in potatoes are a problem that cannot be ignored.
From a national perspective, if you need to choose a doomsday staple food at this time, potatoes will obviously not be the best choice, especially when growing potatoes requires a lot of light.
It was because of these factors that Chen Xin chose upland rice as the main food source for his refuge.
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After sending Qin Lan and Ding Ning away, Chen Xin tidied up the place and sat in front of the workbench.
While taking out the pistol he had just exchanged from Qin Lan and placing it on the workbench to press bullets into the magazine, he was also thinking about making an oxygen concentrator for Mo Qingyan.
Although he chose a very simple and rough production method when getting an oxygen concentrator for himself, and later relied on system upgrades to obtain the oxygen concentrator, this approach was still too extensive.
Moreover, the overly simple oxygen concentrator he made before was really not worth mentioning in terms of efficiency, and the utilization efficiency of light energy was still very low.
However, after upgrading the system, even Chen Xin's simple and crude oxygen concentrator now looks decent.
Chen Xin chose the second option to upgrade. The original square plastic box was turned into a straight hollow tube. The fill light was directly installed in the hollow part of the tube and illuminated directly from the inside to achieve maximum efficiency. of light energy utilization.
The algae are raised directly in the circular tube for reproduction, and the oxygen produced is discharged from the top, while there are pores at the bottom to inject carbon dioxide.
The settled algae corpses will be filtered during the water circulation process to recover biomass, which is used to generate methane to supply fuel cells for power generation.
After the upgrade, the entire system has turned into a green cylinder with a height of two meters. The light is faintly shining from inside, and the entire cylinder is filled with algae.
The oxygen produced by such a device can sustain the survival needs of a normal person, and the electricity generated can sustain the energy consumption of the entire device except for the fill light, with a slight surplus.
After all, under normal circumstances, algae oxygen generation technology relies on sunlight to promote photosynthesis of algae. Now that there is no sunlight, this part of the energy consumption of the fill light must be supplemented by other energy sources.
Mo Qingyan's shelter has the city's power supply and water supply. Although the supply is limited, it is not a problem to maintain the operation of the equipment.
After pressing the bullets into both magazines, Chen Xin inserted one of the magazines back into the pistol.
After holding the gun and feeling it, he couldn't help but take out the pistol he made and put the two guns on the workbench for comparison.
Compared with the pistol Chen Xin made himself, the pistol Qin Lan gave him was obviously larger in caliber and lighter in weight. This was because Yan Guo used engineering plastics as the handle when manufacturing the QSZ92G semi-automatic pistol, which reduced the gained a lot of weight.
As for other performance differences, Chen Xin could not compare the quality of the two guns without actually taking them out and shooting dozens of rounds of bullets. That required extremely professional knowledge and experience in using firearms.
After some consideration, Chen Xin decided to use the pistol he obtained from Qin Lan as a weapon for daily self-defense, and the pistol he made himself was placed on the bedside table in the bedroom as a backup.
This is also a safety strategy. Having weapons and equipment ready near you is a good way to improve your ability to deal with danger.
Although in Chen Xin's opinion, as long as the door of his shelter is closed and there is no heavy firepower, it is difficult to cause him any security problems that require the use of guns.
But to be prepared, if you encounter any problems, it is still important to have a gun on hand.
After doing this, Chen Xin took out his bow from the weapon cabinet.
Archery was just a hobby cultivated by Mo Qingyan in the past and had no practical use.
In the doomsday, the role of bows and arrows has been greatly reduced with the advent of guns. In a sense, the existence of this bow has become useless.
What's more, as the outside temperature drops, the maintenance of the bow and arrow itself becomes a problem if it is taken out for use.
So Chen Xin plans to see if this bow can be used for other purposes after upgrading. If so, he plans to upgrade the bow into a crossbow and then install it at the upgraded gate to use it as a defensive facility.
Maybe you can't use the bed crossbow to backstab, but it doesn't say you can't use the bed crossbow as a trap. (End of chapter)