What were the impacts of immigration of south america

A low birth rate can lead to a decline in the labor force, reduced demand in certain industries such as housing and reduced home prices due to weaker demand, and a slowing and less dynamic economy. Immigrants, however, can counteract these effects

Explanation:

the great wall of china worked as a defense for the feudal states of the zhou dynasty to the north. during the warring states period more walls were put up to defend the borders of the different kingdoms. it was semi successful because despite the wall, the mongols eventually conquered china also the great wall provided protection to the economic development and cultural progress, safeguarded the trading routes such as the silk road, and secured transmission of information and transportation. @jayxboof