Li Ke's words left all the ministers speechless, but after a moment of silence, Fang Xuanling spoke: "Your Highness, there is nothing wrong with what you said, but it doesn't matter how the powerful family in the world chooses us. I know very well, so I can only say that I should try my best to guide them. This family has several different ideas, not to mention there are so many wealthy families in the world."
Fang Xuanling's words are undoubtedly a step down for everyone.
Li Ke naturally didn't mind either. If Lao Li hadn't asked him to talk, Li Ke wouldn't have bothered to say this.
"Well, there is nothing wrong with what Duke Wei Guo said, but everyone needs to pay more attention to this aspect. In addition, since dad and everyone are here, I have something to tell you." Li Ke said.
"Say it." Li Shimin said calmly.
"I want to restrict the cultivated land and relocate the people in the main loess areas of Guannai Road and Hedong Road." Li Ke said, "Go, Huo Gang brings a map."
"Yes." Huo Gang, who was far away, turned around and looked for a map in the cargo being loaded and unloaded nearby.
Everyone has no idea about the Loess Area or the Loess Plateau, but everyone must know the two roads Li Ke mentioned. "Why?" Li Shimin asked strangely.
"Soil erosion." Li Ke said.
"Soil erosion?" Everyone was a little confused.
"Most of you have read history books. You have read the Four Books and Five Classics, Spring and Autumn Period, etc. Do you have any impression of when the Yellow River was called the Yellow River? And why is it called the Yellow River?" Li Ke looked at it. asked everyone.
Everyone was stunned for a moment, and after a pause of dozens of seconds, Li Chunfeng in the crowd said: "Returning to Your Highness, if I remember correctly, around the end of the Sui Dynasty, some literati based their views on the middle and lower reaches of the Yellow River. Some people began to call the Yellow River the name of the river."
"That's right." Li Ke nodded simply, "Why is it the late Sui Dynasty and not the earlier dynasties? That's because the water in the Yellow River has begun to become turbid."
"The water quality in the middle and lower reaches of the Yellow River began to turn hazy, and the originally clear ocean near the mouth of the Bohai Sea also turned into a hazy color. I asked the people whose ancestors lived near the mouth of the Yellow River near the Bohai Sea, and they said Ancestors ago, when the Yellow River entered the Bohai Sea, the water flow was still clear, but it still carries a lot of sediment."
"And these sediments come from the loess area in the middle and upper reaches of the Yellow River, which is what I call Hedong Road and Guannai Road."
Everyone is a little confused. To be honest, they understand, but they don't understand the key point.
Huo Gang had already brought the map, and Li Ke called two little eunuchs to hold it up, and then drew a rough outline of the Loess Plateau area on the map for everyone.
"Everyone, this is the area where the Loess Plateau is located, and it is also the main farming area where our Chinese civilization has developed to this day."
"There is a saying in "Zhuangzi": When the rivers are exhausted, the valleys are empty, and when the hills are flat, the deeps are real. This means soil erosion, because the number of people in these places is increasing year by year, and when the people cannot survive, they will open up more areas. Grain is grown in wasteland, but one consequence of opening up wasteland to grow food is the reduction of trees and forests, which in turn reduces the tree root systems that stabilize the earth. When water flows through, it will carry away a large amount of sediment."
"Some officials from the Ministry of Industry who often manage river banks and flood disasters should know that if a river flows through a flat plain, there will be dirt on both sides. There will often be some dirt entering the river water on the banks of the river, and the river banks will also change year after year. , but if both sides of a river are full of trees, then the banks of the river may not change much for decades or even centuries."
"That's what tree roots do to stabilize riverbanks."
"The principle is actually the same as when we build a house, we mix wheat and rice straw into the yellow mud and then put it on the wall. It is the same as when I use cement to make ferroconcrete and add iron bars to the cement to increase the strength. The root system of the big trees in the earth plays this role." Li Ke said.
When Li Ke said this, some ministers who were not good at architecture understood instantly. Most of them looked at Li Ke in surprise. His Highness did not expect to be able to connect the principles of these completely different activities.
"These places on Guannai Road and Hedong Road are large loess areas. In the past dynasties, this area was also an area where the population was relatively concentrated. Therefore, a large number of people cut down trees and reclaimed wasteland for cultivated land. There are fewer and fewer trees in these places, and water and soil erosion are also increasing. It’s getting more and more serious, like on some mountain slopes, if they were originally covered by forests and vegetation, even heavy rain would be nothing.”
"But without trees and a lot of vegetation coverage, once it rains heavily, the rainwater will quickly gather to form some small streams carrying soil down the hillside. Many loess mountains in the Loess Plateau have formed thousands of ravines. This is Favorable evidence of soil erosion.”
"Then these streams will gradually converge into rivers. These rivers are all tributaries of the Yellow River. Finally, the tributaries carry sediment and merge into the Yellow River. The water of the Yellow River begins to become turbid. In the long run, I am afraid that at most one or two hundred years, the lower reaches of the Yellow River will As the sediment accumulates and the river channels accumulate, the lower reaches of the Yellow River will inevitably change its course! By then, I am afraid it will be flooded and starve to death all over the land."
Li Ke's words are not without purpose. The diversion of the Yellow River is very terrible. It is not just a few simple lines of writing in history.
Anyone who has experienced the 98-year flood disaster in later generations will know how terrible it was. You must know that it was just a flood disaster, but what about the river's change of course? ! In ancient times, there was no strength to seal the breach.
"What His Highness said is absolutely true. I am from the Wang family in Taiyuan. On the mountain near my home, there is a hill that originally had many trees. I used to go hiking there when I was a child. There are no ravines on the mountain as Your Highness said. But then people reclaimed wasteland and the trees on the mountain were cut down, and now the hill has been washed away by rain to form several deep ravines."
"Now that I think about it, where did the soil in that ravine go? I'm afraid it all flowed into the Yellow River." Among the ministers, a middle-aged man in his forties said.
"Does His Highness mean that we should start planting trees in this loess area?" Duan Lun asked with a grimace. Needless to say, this was a matter for his Ministry of Industry.
"Yes, planting trees is one thing. Let the people plant trees and take care of the food in all the areas that have not been opened up during the slack period!" Li Ke said simply. In this era, as long as the food is taken care of, the people can take care of it during the slack period. The whole family is willing to come out to help, and children are free.
"In addition to wasteland, in the remaining farmland of the common people, according to some local weather and climate, see if there are any fruit trees that match the local characteristics. These fruit trees can also fix the water and soil, and secondly, they can also increase some income for the people. ."
"Also, doctors from the Ministry of Industry and the Imperial Medical Office can investigate how many medicinal materials grow in the local mountains, and the conditions for the growth of these medicinal materials. For example, some medicinal materials like to grow under trees. The herbs can be combined with the common people to plant trees and then plant them. Hasn’t the Imperial Medical Office always had some herbal cultivation techniques in the rows between saplings? They have all been promoted.”
