A very good video on Chinese economy

[Dungeness]

the reason i asked is because china is building more and more factory this means fertile land will be reduced.

There is red line (min. 1.8 billion mu-or 120 million hectare) designated by central government, which no one dare to across.

 

[Bussard Ramjet]

There is red line (min. 1.8 billion mu-or 120 million hectare) designated by central government, which no one dare to across.

Not only that, a lot of factories are also being replaced with newer ones, as China climbs up the value chain. I don't think any new land is needed at all, if the current one can be managed well.