Qian Rujun wants to control water, and the biggest advantage of water control is that it can produce a large range of irrigable fertile land, and from the seedling to the mature stage, it can not be dried up and killed, which can reduce the harm of one death.

There are many hazards that will cause crop death, drought is one of them, quite serious, if you can ensure that the farmland has enough water, in fact, even if there are other disasters, you can avoid because there is enough water.

In fact, even if it is not farmland, there is a lot of food that can be eaten by various creatures in nature, and these creatures exist under the cycle of nature, and will not cause the death of certain organisms due to some mutated factors, causing imbalance.

Therefore, if you can manage the water well, not only can you let it flow out, relatively smoothly, but also when it flows out, you can take out the water and use it by the way, water is very important for the growth of crops, and even if you can leave all the water on land for use, for many people, this is a great success.

However, for marine resources, this may be a kind of harm, but in this era, the utilization of marine resources is still relatively small, even Jinmaicheng is not the most fully utilized, in most cases, it still has to be made into dried fish to be able to sell, but the biggest problem with dried fish is the taste of seafood, which will basically lose a lot.

Dried fish, not as delicious as fresh fish, unlike shiitake mushrooms, even if they become dried, they still have a special flavor, which many people like very much.

The whole Dahan River and Lake are very numerous, probably more than humans in the 21st century can imagine, because in this era, the rivers have not yet accelerated the speed of their entry into the sea through the massive drinking and rapid flow of human beings, and the rivers are now on land, and the speed of flowing to the ocean is six times slower than in the 21st century.

As a result, the water on land is now too abundant, and most of the land that has been silted up by water is not usable land for human beings, because they lack the proper tools to open up this water into a usable water, even if it is opened up into a pond, but the trade in this era cannot be sold for a long time, so after the fish pond is opened, the place where it can be sold is limited.

There is no preservation technology that can keep the fish longer, only to keep the fish alive after being caught, and then it can be sent to the original place.

In the Han Dynasty, there was not even such a thing as canned fish, but when Qian Rujun began to make canned fish, many people followed suit, and even some people not only made canned fish, but also made a lot of canned meat, which was sold all over the country.

Qian Rujun also developed stinky head rot at the same time when canned food came out, but in this era, the emergence of a lot of stinky tofu does not mean that it is a delicacy, because the stinky tofu that fails to make it is really stinky, and frying this kind of thing, for them, consumes too much oil, and animal oil is not suitable for frying.

However, the vegetable oil produced by Qian Rujun began to popularize a large number of good things, especially those related to people's livelihood, people will find ways to crack and try to produce, and Qian Rujun did not do much to conceal the birth of vegetable oil.

Qian Rujun always thinks that her things are delicious, because the space is essentially good, even if it is made into oil, it will sell better than other places, because the oil they make can't reach its taste, and other people have cheaper oil to use, which is a good thing for the whole Han, Qian Rujun is the representative of the good deeds of the good people who came to the Han.

Due to the influence of monsoon climate, the spatial and temporal distribution of precipitation is uneven.

This may be a simple sentence, but when placed in different terrains, it will produce different results.

And when the seasons change, and even when the land does not adapt to some sudden changes, there will be some more disasters, which are not usually happening, but will happen at some point.

Because of the vastness of the land, many rivers have been incorporated into another river before they have dried up, and this river, from a dry place, or a high place, to a place where it rains more and more, has caused more and more water to flow, and in the case of more and more water, it is more and more gentle.

As a result, the water of the most important rivers can suddenly increase in one place, causing a large flood of the entire basin.

If the river has the function of regulating flooding, for example, a lake.

However, next to the lake that regulates the flood function in this way, no one can enclose the lake to create fields, otherwise this regulating function will be lost.

Therefore, water control must also curb people's greed.

In the Han Dynasty, it was not too much of a problem, because there was too much land for people to cultivate, just explain the place, if the harm of farming was, after that, the power of the people prevented them from destroying these places.

But if the population increases, when the land becomes insufficient, the land will be selfishly exploited, but when the land is suffocated and developed, more land next to it will lose its usability or still be usable, but it must be honest and encounter the problem of flooding.

Therefore, after the flood control, if there is no administrative order to solve this problem, the effect of the water control will be very poor, and even a few years will consume your energy, and the results of the water control will be completely beaten back, and the person who fights back does not have a very sinister heart, he just wants a land that can be cultivated.

makes you both helpless and lamentable, making people want to scold him, but they can't scold him.

However, the rivers governed by the state money of the Han Dynasty could only be the seat of the central government, and he had no way to govern the seat of the central court, unless it was the Yangtze River and the Yellow River.

For the people of the Han Dynasty, floods were inevitable, and they had to turn to the gods for help, and if they were affected by disasters, people could only use the power of the group to find a way to help each other and get out of the flood.

Keep a life, and then continue to work hard to continue to live, if you can't live, you can only choose death, but most people are very resigned to life to find a way to produce, so that they can live, by the way to raise some people who need them to feed, the court is a parasite on people, but if there is no big problem in the court, they have no way to solve it with their own strength, so they admit that the court is necessary to exist.

Floods will not only cause a large number of casualties and property losses, but also cause a large number of disaster victims to become displaced people and homeless people to mobs if the disaster relief is not timely or appropriate, which will bring a lot of trouble to the Han court.

People's normal life will also bring huge losses, and even cause turmoil and affect social stability. Therefore, water control is of great significance.

If Qian Rujun has been flying outside, and then drawing hydrological maps on the spot, for Qian Rujun, this time is too much time, so Qian Rujun often takes a look outside and enters the space to draw.

After drawing the image in your memory, you can continue to fly.

In fact, this kind of work is very boring and very mechanical.

But Qian Rujun felt that he was doing something meaningful, so although it was a mechanical thing, Qian Rujun was happy to do it.

It's just Qian Rujun, but let the ordinary people below see more figures flashing in the sky.

Qian Rujun was at work, but he forgot to change his appearance a lot.

The appearance of an unknown object in the sky was slowly reported to the center of the imperial court.

The people who belonged to the Central Tower District of Chang'an City and Jinmai City slowly got a feeling from this report that Qian Rujun seemed to be back and was doing something.

So they began to contact Qian Rujun, and Qian Rujun also told them exactly what she was doing.

Flying in the sky and observing hydrogeography, there is no way for them to replace Qian Rujun's work, but there are many things that Qian Rujun wants to investigate, and they can't do it in the sky.

Observation from the ground is also very important.

Qian Rujun knows the flow direction of hydrology, but they can feel the ups and downs of the terrain from the surface, Li Bing, who passed by, once did a water conservancy project such as Dujiangyan, so most people have a concept of water diversion and irrigation, even if they have not seen it, they have heard the story of Li Bing's water control.

So they know that what Qian Rujun wants to investigate is to make a water tank to irrigate the land, if Qian Rujun does a larger area of the water tank, the greater the cost, but the more fields will be obtained, but these things should be the affairs of the imperial court, after the imperial court obtains these lands, it will begin to distribute to the people.

For the common people, one of the reasons why they do not open up new ones is actually the problem of hydrology, and these places that have not been opened up into fields are flooded at any time in this era, not just the problems of wild beasts.

In order to allow water to flow to every place in a reasonable manner, and to stabilize the flow of water, it is necessary to allow the water to flow out of the water without allowing the higher water to flow into the water basin by the way.

For the water in this era, all the drainage principles are in accordance with the power of nature, and it is also the most time-saving and labor-saving, and does not need to consume man-made forces.

But if you want to do it without using human power, you have to have a lot of ingenuity and design, and each waterway may have a different water design.

Qian Rujun knew that if this matter only existed, it was estimated that there would be no way to complete it, but he had cultivated the students of Xuetang Island, each of whom had some concepts in this regard, and with their wisdom, if they wanted to study the most reasonable design of each river, they might be able to do it, but it would take a lot of time.

The appearance of the students on Xuetang Island was originally a selfish idea of Qian Rujun, who wanted to escape from the Han Dynasty to travel to various places, but he was afraid that he would not be able to cope with the pressure from the outside world, so he took a group of people to go with her.

In the end, in order to train the various abilities of the students on Xuetang Island, she opened up a lot of courses for the students of Xuetang Island to study, and Xuetang Island lived up to expectations, almost no matter what problems she had, the students of Xuetang Island were able to hand over perfect transcripts, because Qian Rujun never taught a person to do a thing, always called a group of people to do things together, and a group of people is the accumulation of wisdom for Xuetang Island students.

He knows that this kind of thing is to deal with floods, and he may not be too unfamiliar to the students of Xuetang Island, even if she has not mentioned the problem of water control before, most of the talented people will study it, and she believes that some of the students of Xuetang Island should focus on studying the problem of flooding, because they know that the princess is a person who is interested in all things in the big man, so they must produce talents in every major.

Qian Rujun has a memory of the 21st century, and probably knows where there are big rivers, and it is not the best to use river water to irrigate the main stream of these big rivers, but the tributaries of the rivers, and they can divert water from their tributaries.

In order to complete the task, Qian Rujun can not fly slowly, Qian Rujun's speed has accelerated, under her full efforts, she has analyzed most of the main rivers north of the Yangtze River, especially in later generations have been fully developed into farmland, the Han Dynasty should have river energy water can be diverted for irrigation.

Qian Rujun's words about controlling the water were distributed to the students on Xuetang Island along the way.

The students of Xuetang Island are gathering on Xuetang Island, and Qian Rujun's summoning began to go to their designated places, and they know that when they see the princess now, the chance to enter Xuetang Village is reduced.

Fortunately, they are used to such things, and they know that as long as they do things well, sooner or later, Qian Rujun will give the students of Xuetang Island a reward.

Qian Rujun knew that water control was a strange thing for the students of the academy, so Qian Rujun did not let the students of the academy island be separated, a group of students went to one place and another group of students, and Qian Rujun would go to see them when the time came.

This is their first time controlling the water, so the strength of the group is very important, the group is a unit of fifty people, and for the students of Xuetang Island, fifty people is enough for them to find someone who belongs to the water conservancy management class.

Even if they don't, it doesn't matter, because they will come up with a way to solve things, and all the knowledge is based on reality, but the methods of the rich allow people to take a few detours, but in terms of water conservancy management, they must understand the basic principles of water conservancy.

Each of them has a basic understanding of this aspect, and when they have a basic understanding, they will be able to see through all the truths more simply than some people who have no foundation at all.

Qian Rujun did not go to the designated place in advance, but left some information in that place for them to study, Qian Rujun still continued to investigate and study back and forth in this place, and drew various hydrological maps, because only she could do these tasks, and no one could replace her, so Qian Rujun did it very seriously.

When she felt that the students of the school island were almost assembled, she appeared in front of the students of the school and took them into the space.