As an important strategic measure of "border protection", what is the significance of the settlement of land in border areas by dynasties?

First, it played a key role in ensuring that the central government established political order in the border areas.

After the reclamation and development of dynasties, many places in China's vast frontier ethnic areas have become fertile land and mature soil, and become bases to adapt to agricultural production. The promotion of agricultural economy to the frontier is undoubtedly conducive to solving the supply of soldiers and officials in the frontier, especially to maintaining the administrative jurisdiction of the central government in the frontier ethnic areas, and is of great significance to ensuring the stability of the frontier ethnic areas and the consolidation of border defense.

Second, with the development of reclamation, the social economy of the frontier has developed and the number of military reserve horses has been increasing, which has enabled the dynasties to improve their comprehensive defense capabilities and maintain their military presence in the frontier on the premise of solving the livelihood of frontier officers and soldiers, thus making the frontier a reliable strategic barrier for the Central Plains and playing a certain role in defending the frontier and resisting the nomadic people's southward migration. As Zhao Chongguo said, "Reclaiming land from the sea has both the benefits of death and the benefits of defense."

Third, the frontier reclamation work characterized by the combination of military and civilian, peacetime and wartime, and military and agricultural integration not only ensures the security of the frontier, but also mobilizes all the forces in the frontier to participate in the economic construction of the frontier, effectively developing the frontier, which is of great strategic significance for consolidating the frontier and maintaining the long-term stability of the frontier.