By the end of the Ming Dynasty, China's population had long exceeded 100 million, but it did not exceed 200 million, and according to various estimates in later generations, the Chinese population at the end of the Ming Dynasty was at most about 150 million. Pen, fun, pavilion www. biquge。 info

Although this figure is not small, it was definitely the first in the world in the 17th century, but compared with the total population of China in later generations, it is really a drop in the bucket.

In particular, the center of gravity of the Chinese population at the end of the Ming Dynasty had actually shifted to the south, and the two banks of the Yangtze River were the most densely populated places at that time, and as for Shaanxi, Shanxi, Hebei, Henan and other places, the population density was not the largest.

As for the towns under the jurisdiction of the nine sides, the population density is even smaller. The reason why these places were the first to appear and the most displaced people was because there were too many natural and man-made disasters in that era.

The first half of the seventeenth century is now recognized as the Xiaoice period in world history, and the annual frost and snowfall are about a month earlier than the previous time, not only the cold weather is early, but the winter temperature is also lower.

This is also the fundamental reason why Emperor Chongzhen later issued an order to let Xu Guangqi be in charge of Qintianjian and recompile the calendar with the help of Western missionaries such as Tang Ruowang.

This re-revised calendar is historically called the "Chongzhen Calendar", and the lunar calendar used by later generations is repeatedly revised on the basis of this Chongzhen calendar.

Once this long-term climate change occurs, the northern border, which is already cooler and less arid and rainy, will become even more unsuitable for traditional crop cultivation and human habitation. This is also the external objective reason why the Mongols continued to plunder in the south, while the Jurchens continued to invade the south.

This was not only the case in China at that time, but also in Europe in the first decades of the seventeenth century, because of climate changes, and was in a situation of chaos among other countries.

When Emperor Chongzhen ruled China, it was also the time when the German Thirty Years' War was at its peak.

Although the climate environment is getting worse, the Ming Dynasty is not without a chance to change, but the Chongzhen Emperor in history did not seize this opportunity.

For Zhu Daming, the solution to climate change is very simple, one is to immigrate, since the north can not afford more people, then emigrate, migrate to the south, migrate overseas, and open up a larger living space for Chinese people to live in, such as Dongfan Island, Qiongzhou Island, and the vast Southeast Asia.

At that time, Dongfan was the island of Taiwan in later generations, and Qiongzhou was naturally Hainan Island in later generations. In the first half of the seventeenth century, these places were more suitable for human habitation than northern Shaanxi, northern Shanxi, and northern Hebei.

The other is to change crops. Since wheat, rice, and millet are not enough to feed people in the increasingly cold, arid, and rainless north, other crops can be planted that can adapt to this climate.

There are such crops, that is, sweet potatoes, potatoes and corn that came from overseas and were already grown in the mountainous areas of Fujian and Guangdong at that time. As soon as he thought of this, Zhu Daming looked forward to Xu Guangqi's arrival even more.

The day after arriving in Tongzhou, Xu Guangqi temporarily left the rest of his entourage and set off with only two cronies and servants, riding the stagecoach provided by Luheyi, and speeding up the pace of entering Beijing to meet the emperor.

The servant carried the emperor's holy decree appointing him as the secretary of the Ministry of Rites, so the journey could be said to be unimpeded, and before the people arrived at the General Administration, Wang Chengen had already waited at the entrance of the General Administration Department with a group of people.

If it weren't for the fact that it was too late when the news came in from Luheyi last night, Wang Chengen would have arrived at Luheyi to greet him in person at this time.

The emperor's attention to Xu Guangqi, Wang Chengen knows best. Since the holy decree of the summons was issued, the emperor asked people whether they had arrived in three days or two, and as for how many times he asked, Wang Chengen couldn't remember it clearly.

A minister with personality, Wang Chengen has seen a lot, but like Xu Guangqi, who received the emperor's holy decree appointing him as the secretary of the Ministry of Rites, he is still so slow and not in a hurry to get on the road, and he is the only one. But looking at the emperor's meaning, there was no sign of anger at all.

Xu Guangqi is not a rotten Confucian nerd, and he is also courteous when he meets the legendary emperor's henchmen, which makes Wang Chengen's impression of him even better.

Soon, Xu Guangqi arrived at Qianqingmen under the leadership of Wang Chengen, and then went in to report, and he came out to greet the new Ming Emperor who had not met.

In Xu Guangqi's eyes, the emperor was neither tall nor short, with a thin figure, a fair face, and he walked step by step, full of confidence.

was still more than a dozen steps away, and after confirming that it was the identity of the other party, he stood and waited for Xu Guangqi to quickly kneel on the ground and shout long live.

Zhu Daming hurriedly stepped forward, tightly hugged Xu Guangqi's arm, and said repeatedly, "Aiqing is exempt."

Zhu Daming respected Xu Guangqi from the bottom of his heart for a scientist who had studied both China and the West, and under the witness of many great eunuchs and Gong Wei Si personnel in the inner court, Zhu Daming held Xu Guangqi's hand tightly and entered the Qianqing Palace together.

Since then, the whole Jingshi has known that the new secretary of the Ministry of Rites, Xu Guangqi, has a status in the emperor's mind, which can be said to be better than Sun Chengzong.

The two sat down in the East Warm Pavilion of the Qianqing Palace, that is, the emperor's imperial study.

Zhu Daming looked at Xu Guangqi, who was sixty-four years old and his hair and beard were a little gray, and said, "Why did Xu Aiqing come late?" Is the Tianjin affair over? ”

When Xu Guangqi heard this, he said that the emperor seemed to be a little concerned about his tardiness, so he said: "Your Majesty treats his ministers very well, and there is no such thing as ancient times. The minister has been in Tianjin for many years, experimenting with several foreign farming, and recently he is making some gains, and the reason why he stayed in Tianjin for many days is actually to repay him when he meets His Majesty. ”

Zhu Daming was immediately happy when he heard this, he hadn't mentioned this matter yet, Xu Guangqi took the initiative to say, it seems that there is a way for high-yield crops suitable for reclamation, and he didn't hide his excitement at the moment, and hurriedly said: "Aiqing has been in Tianjin for many years, and he once said that the sweet potatoes mentioned by Shangshu have been successfully planted?" ”

Xu Guangqi saw that the emperor was excited, and he was very happy in his heart, and said: "Back to Your Majesty, not only sweet potatoes, but also the seeds that the minister tried to plant in Tianjin, there are also soil taro and stick grain. Although these crops originated from overseas, they are quite adaptable to the land of the Ming Dynasty, and compared with the old grains of China, the yield is larger, more drought-tolerant, more cold-tolerant, and can grow even in the saline-alkali land of Tianjin Binhai. In particular, the taro, creeping, the leaves are like beans, the rhizomes are round like chicken eggs, the inner white skin is yellow, boiled, can also be steamed, and the yield is particularly large......"

The more Zhu Daming listened, the happier he became, but he was worried that what Xu Guangqi said was not the potatoes and corn he was familiar with, so he said: "Aiqing can bring real things, and let me have a look." ”

Of course, Xu Guangqi brought the physical object, which was originally a gift to the emperor, but it was inconvenient to bring it into the Qianqing Palace, and it was left in the emperor's guards outside the Qianqing Gate.

Soon, Wang Chengen came in with a cloth bag and handed it to Xu Guangqi. Xu Guangqi opened the bag in front of the emperor, took out an object from it, and Wang Chengen handed it to the emperor.

Zhu Daming looked at this round little thing, and a stone fell to the ground in his heart. Sure enough, it's a potato!

The taro in the Ming records is a common potato in later generations, but it is a little smaller than that of later generations, and there is not much difference. This is a lifesaver! After Zhu Daming saw this, he felt much more at ease.