Can crabs be raised in the desert? Yes, they will soon be on your table! | Expo Daily

Can crabs be raised in the desert? Yes, they are coming to your table soon!

It’s autumn again, a time when crab lovers are delighted. They quickly place orders for several kilograms of large crabs, looking forward to tasting them when they get home after get off work. But did you know that these roe-rich, yellow and plump crabs may actually come from a place that seems to have nothing to do with crabs: the Taklimakan Desert?

Xinjiang is a province with a relatively high proportion of saline-alkali land in China, accounting for about 30% of the country's saline-alkali land area. According to relevant surveys, in the past 50 years, Xinjiang has reclaimed more than 50 million mu of saline-alkali land. The main components of Xinjiang's saline-alkali land are sodium chloride, sodium sulfate, sodium carbonate, calcium and magnesium.

The weak alkalinity of the soil makes it difficult for general crops and plants to survive, but it is a favorable condition for crab farming. The salt in the saline-alkali land can meet the mineral needs of crabs for growth, becoming a "unique nutrient" for crab growth. Large areas of saline-alkali land can also meet the density requirements for crab farming, and have good innate conditions.

What about the water? The Yulong Kashi River and other rivers flow through the Hotan area on the edge of the Taklimakan Desert. During the flood season, the water from these rivers can be introduced into the aquaculture ponds. With the help of rainwater collection systems, recycling and water-saving technologies, drip irrigation, sprinkler irrigation and other water-saving irrigation methods, the evaporation and waste of water can be reduced.

Aquaculture can improve the local ecological environment of the desert to a certain extent. Crabs eat benthic organisms and organic debris during their growth, which helps reduce pollutants and eutrophication in the water. At the same time, the crabs' ability to dig soil can also help improve soil structure, increase vegetation coverage, and reduce wind and sand erosion.

Image source: veer gallery

A lot of viruses are jumping on your toothbrush

Foreign researchers have discovered that there is a place with extremely high biodiversity hidden in everyone's home: toothbrushes and shower heads.

Microbiologists have discovered that shower heads and toothbrushes are filled with an incredibly rich variety of viruses, most of which are being discovered for the first time. The good news is that these viruses don't target humans, but rather bacteria.

These bacteria-attacking viruses are often called "bacteriophages." They penetrate into the bacteria to replicate and multiply, ultimately killing them.

Although researchers know very little about phages, their potential use in treating antibiotic-resistant bacterial infections has recently attracted much attention. After all, the enemy of my enemy is my friend. So these unknown viruses lurking in our bathrooms could be valuable materials for exploring these applications.

At the same time, researchers remind people not to worry about microbes in the bathroom, because microbes are everywhere, most of which will not make us sick, and the more you attack them with disinfectants, the more likely they are to become resistant or become more difficult to treat.

The phage sequences in the samples are very diverse

Image source: Stefanie Huttelmaier, Weitao Shuai, Jack T. Sumner, Erica M. Hartmann. Phage communities in household-related biofilms correlate with bacterial hosts. Frontiers in Microbiomes, 2024; 3 DOI: 10.3389/frmbi.2024.1396560

3D printing buildings may reduce 80% of labor

3D printing technology is not unfamiliar to everyone, and you should have heard about it more or less in recent years. But do you know about 3D printing buildings?

3D printing architecture integrates bricks, concrete, experienced workers, and tools into 3D printers. However, the steel cage or steel column will hinder the movement of the 3D printing head. There are currently three ways to solve this problem.

The first type is called the "zongzi skin" type. First, a "skin" is printed, and then the reinforcement is arranged in the traditional way, and then the concrete is poured in. It is nominally 3D printing, but it is actually traditional pouring, so it is just a "zongzi skin".

The second type is the "beggar's chicken" style. Just like we keep putting mud on chicken, we print on the ready-made steel bars and finally make a thin plate.

The third type is called the "roujiamo" type. First print a layer of concrete, then put a layer of steel bars on top, and then print another layer of concrete to cover the two layers.

In the entire cycle of 3D printing, it can reduce construction waste by 30%-60%, reduce labor by 50%-80%, and save 50%-70% of construction time. Therefore, 3D printing buildings have shown some great potential and advantages.

The content comes from the speech of Wang Zhendi, professor-level senior engineer of China Building Materials Academy, at the Gezhi Lundao.

Turning waste into treasure, does gutter oil have a second life?

When it comes to gutter oil, many people's first reaction is that it is harmful to health. However, if the gutter oil is used in the right place, it can also bring out its value. Let's take a look at its applications in my country's bio-aviation fuel technology?

The content is compiled from China Science Popularization Expo Weibo, Science Popularization China, CCTV News, Science Academy, and Gezhi Lundao Forum

This article was first published on China Science Expo (kepubolan). Please indicate the source of the public account for reprinting