25% tax every year on land in the country side if the owners don't farm the land themselves in South Korea. The land cannot be developed. The owners become desperate sell & the price plummets, because holding onto it is costly.
That's how the government confiscates land in modern times to take the country toward socialism.
Also, Chinese are buying the farmlands, then leave the country.
So they set up a system that forces farmland sales at dirt cheap prices to the state or to Chinese.