China is a traditional agricultural country. For agricultural production, the first step is to reclaim the land, leaving nothing else. As for irrigation, fertilization, and even replanting and planting cash crops,...... That's later.
The area of cultivated land in China in the Ming Dynasty - according to official statistics,-- has reached more than 700 million mu, and by the early years of the Republic of China, it reached 1.4 billion mu. Still according to the official statistical caliber, about 700 million mu was opened up for the Qing Dynasty, occupying half of it. In other words, the land reclamation in the three hundred years of the Qing Dynasty is roughly equivalent to the reclamation in the previous three thousand years, which is of course a considerable achievement.
From other historical sources, it can also be confirmed that "global reclamation" appeared in the Qing Dynasty, see Wang Yejian's research. Its waves and historically unexplored deep mountains and old forests, raw wasteland, of which the most famous new development areas are the southwest, central south and northeast and other places, compared with the Ming Dynasty's economic center of gravity on the southeast canal line, has formed a great contrast.
After the continuous reclamation of the "recovery period" in the early Qing Dynasty, by the Yongzheng period, the number of cultivated land in China reached 900 million mu. It is not possible to stop abruptly, but it has to roll forward, albeit at a much slower rate. Therefore, it is estimated that of the 1.4 billion mu of arable land in the early years of the Republic of China, perhaps 1.2 billion mu was reclaimed during the Qianlong period. However, the reclamation of the Qing Dynasty underwent major changes, and it did not blindly attach importance to reclamation as the previous dynasties did. On the one hand, land development supported a large part of the qing dynasty's economic development, see Perkins' study. Reclamation policies, on the other hand, have undergone a "timely" shift. It was completed in the early years of Qianlong.
At the beginning of the Qing Dynasty, the most reclamation was beneficial and con. Regardless of personal or other reasons, Emperor Shengzu did not want to "search" since the 1920s of the Kangxi Dynasty, and then put forward the idea that "there is no idle place in the interior" and "in addition, there is no land that should be reclaimed".
However, land reclamation is, after all, one of the most effective traditional methods, and has been tried and tested for the "restoration period" of the dynasties; in terms of administrative style, the Yongzheng Emperor changed "leniency" to "strict core", so he re-emphasized land reclamation, and the history said: "Yongzhengjian supervised the reclamation of the provinces, which was quite useful for strengthening the people." This has caused dissatisfaction among the government and the public.