Liu Ponu said that he wanted to build the road, and the little mule's mind was also on building the road.

Wuwei, Zhangye, Jiuquan, Dunhuang, along the way, the task of the little mule was added, and people began to go to the field to investigate the conditions for road construction.

Of course, there is no need to investigate the Hexi Corridor along the way, and there should be no surprises if nothing else.

The climate here is pleasant, and the grass is everywhere, so you only need to leave a large enough open space to use it as a road, and there is no need to deliberately build it at all.

At most, if it has been pressed for a long time, the road will be lower than on both sides, and then you can just sprinkle a layer of soil on it to make it higher than the surrounding ground.

However, the good mood did not last long.

Liu Ponu's ultimate goal was to build a road from Chang'an to the Western Regions, so it was naturally impossible for this road to end at Yumen Pass in Dunhuang County.

And after the army left the Yumen Pass in the west, nature taught the little mule a good lesson.

When you enter Dunhuang, you can obviously feel that the green plants are reduced a lot compared with Jiuquan and other places, but when you leave Dunhuang, you find that there is a piece of loess around, and there are a lot of sand and gravel mixed in the loess.

Occasionally, when a gust of wind blows, the sky is covered with yellow dust, and people will be covered with dust when they stay outside to pee.

What's more, the little mule not only let people observe the terrain and geology on their way, but also constantly learn about the guide and then let the guide take him to some places for field trips.

After living for more than ten days in a hurry, the little mule came to Liu Ponu again in disgrace.

"Brother Nu, I think we really need to think about building roads......" The little mule was full of exhaustion, but still said strongly.

"There's nothing to think about, this road has to be repaired!" Liu Ponu shook his head after hearing this.

Of course he knew it was difficult, and he knew that the little mule had been running around to investigate the terrain and geology all these days, and now he said that he needed to think about it, not just because he thought the project was too difficult.

Of course, this road is difficult to repair, but no matter how difficult it is, can he have a Qinghai-Tibet road?

Although the current strength is different from that of later generations, Liu Ponu knows very well the importance of a road in his heart.

The Western Regions is not only a place to demonstrate the prestige of the Han Dynasty, but also a place for the Han to control more distant forces, and the Western Regions can also be a good way for the Han to block the threat from the Western forces.

While those threats are not threats now, they are already there, and it is only a matter of time before they are present.

Liu Ponu knew that the natives who were entrenched in Qinghai later went directly north to occupy the Hexi Corridor, directly cutting off the communication between the Central Plains and the Western Regions.

And now the communication between the Han Dynasty and the Western Regions is only one Hexi Corridor, although it is very stable, but this passage is too narrow, there is no strategic depth at all, as long as the enemy's strength is slightly stronger, and the Central Plains Dynasty is slightly weaker, the other party can almost penetrate it back and forth.

So after taking care of the Western Regions, Liu Ponu planned to set his sights on that part of Qinghai.

The terrain conditions in Tibet are too harsh, and it may not be so easy to recover it for a while, but at least Qinghai must be recovered as the strategic depth of the Hexi Corridor.

In this way, this path is even more important.

The Hexi Corridor will be a base camp for the Han to launch an attack on the Qinghai region, and although it will not be the only one, it will definitely not be the one that cannot be ignored.

"But the terrain here is too complicated, the geology along the way is different, if you forcibly build it, the cost of maintenance behind it is too great, the Gobi in front is better to say, it is nothing more than a little more to sift through, but some places can't find soil at all, even if we transport it from afar, it won't take long to sink, and then maintenance is only one aspect."

"In addition, through my observation and understanding, I found that there is often wind here, and there is often a sky full of yellow sand, if it is not cleaned up in time, it is likely that it will take less than a year to work, and the road we have built will be buried under the yellow sand."

"The only solution is to raise the roadbed, but in this kind of place, how difficult is it to raise the roadbed? Even if we can solve this problem, we can't solve the problem of yellow sand invasion, after the roadbed is raised, the wind and sand will be blocked after reaching here, and it will still be buried by the sand after a long time, and what's worse is that there is more of this roadbed, which may turn the originally normal place into a desert ......" said the little mule with a sad face.

Obviously, he is engaged in industrial construction and commercial operation, but now this trip to the Western Regions has made him a master of infrastructure construction and environmental protection.

From leaving Yumen Pass to passing through Bailongdui, this section of the place was also lived in a long, long time ago.

But as time passed, the area turned out to be no man's land.

The little mule did understand some of the situation, and it is said that it was because the environment was so harsh that the people who originally lived here chose to migrate.

Some of them migrated eastward and entered Dunhuang and other places, while the other part migrated to the west and north, and it is not known where they went.

The main reason for their migration is that the wind and sand are too big to graze, unable to farm, lack of water, if there is no water in a place, then you can find a way to overcome it, but if you can't even grow food, then there is no need to hold on, and you can only wait for death to stay here.

The main reason why the grain cannot be grown is because the wind and sand are too strong, and a wind and sand will flood the farmland, and the grazing will bury the grass because of the wind and sand, and the livestock cannot eat it.

Listening to the little mule's description, a familiar picture gradually appeared in Liu Ponu's mind.

An asphalt road with quicksand everywhere, and some of it is a large amount of sand that takes up half or all of the lane.

The places where quicksand appears are those that have been raised by the roadbed, and the wind blows the sand to create a unique landscape, and the sand occupies the lanes, which is the desert road.

The wind can't control it, but the sand can.

Could it be that you really want to start controlling the desert from now on?

Become the first environmental guru in human history?

The difficulty of controlling the desert is not high, and the cost is not high, the difficulty is perseverance, and the difficulty is to find the right method.

In later generations, there were only two methods, one was to cultivate a large area of green plants suitable for desert survival, and through these green plants, the desert soil quality was changed so that it could be restored to a normal environment.

The other method is windbreak and sand fixation, which is not difficult or too demanding, and the straw is woven into a curtain, and a pit is dug directly in the desert to unfold and bury it, revealing a head.

The curtains are closely connected together to form a grid of Tian characters, and the spacing is about one meter.

The effect of sand fixation is achieved through a large amount of straw, and this method is currently the most effective way to prevent the expansion of the desert, and it can also greatly reduce the probability of the sand being blown away by the wind.

At this time, Liu Ponu had to sigh at Taizu's shrewdness, and as a descendant, this cool ride was also very comfortable.

A construction corps can solve this problem, and it can also ensure long-term effective management, and what the imperial court needs to do is to provide food, drink, and shelter for their group of troops who must be separated from production, as well as some policy issues.

Are these hard?

It doesn't seem to be very difficult for Liu Ponu, there can be many kinds of policies of the imperial court, for example, you can build a free school here, for example, you can give them extra points, etc., with these two policies, there will be no fewer people who are willing to come here.

Thinking of this, Liu Ponu instantly strengthened his belief and said: "You just have to come up with a road repair plan, and you can also list the problems or something, as for solving these problems, I have my own way!" ”