Scientists believe that Mashkan-shapir's collapse was caused in part by destruction of the fields by mineral salts. When mineral salts concentrate in the upper levels of the soil, it becomes poisonous for plants. In Mesopotamia, irrigation was essential for crop production.
Answer:
La Sumeria es una civilizacion que florecio alrededor de 4500-1900 aC
There is a lot of systems what r u asking about
