A northern ruler named Yang Jian unified China in 589, creating the dynasty. Sui Han Song Tang

crop rotation kepy different plants in the soil instead of once constintly. when switching out plants you have different nutrients being absorbed at different speeds and different roots growing differently therfore the spoil and water flow have to adapt and carry fresh nutrients to carry the constant changes that were going on in the soil.

your mom

now im just trying to get this to 20 characters hope it works hey it works hope it okay bye